VOLUME II

=Ink, Lithograph′ic.= _Prep._ 1. Mastic (in tears), 8 oz.; shell-lac, 12 oz.; Venice turpentine, 1 oz.; melt together, add, of wax, 1 lb.; tallow, 6 oz.; when dissolved, further add of hard tallow soap (in shavings), 6 oz.; and when the whole is perfectly combined add of lampblack, 4 oz.; lastly, mix well, cool a little, and then pour it into moulds, or upon a slab, and when cold cut it into square pieces.

2. (Lasteyrie.) Dry tallow soap, mastic (in tears), and common soda (in fine powder), of each 30 parts; shell-lac, 150 parts; lampblack, 12 parts; mix as last. Both the above are used for writing on lithographic stones.

3. (AUTOGRAPHIC.)——_a._ Take of white wax, 8 oz., and white soap, 2 to 3 oz.; melt, and when well combined, add of lampblack, 1 oz.; mix well, heat it strongly, and then add of shell-lac, 2 oz.; again heat it strongly, stir well together, cool a little, and pour it out as before. With this ink lines may be drawn of the finest to the fullest class, without danger of its spreading, and the copy may be kept for years before being transferred.

_b._ From white soap and white wax, of each 10 oz.; mutton suet, 3 oz.; shell-lac and mastic, of each 5 oz.; lampblack, 3-1/2 oz.; mix as above. Both the above are used for writing on lithographic paper. When the last is employed, the transfer must be made within a week.

_Obs._ The above inks are rubbed down with a little water in a small cup or saucer for use, in the same way as common water-colour cakes or Indian ink. In winter the operation should be performed near the fire, or the saucer should be placed over a basin containing a little tepid water. Either a steel pen or a camel-hair pencil may be employed with the ink. See LITHOGRAPHY.

=Ink, Mark′ing.= _Syn._ INDELIBLE INK, PERMANENT I. Of this there are several varieties, of which the following are the most valuable and commonly used:——

1. Nitrate of silver, 1/4 oz.; hot distilled water, 7 fl. dr.; dissolve, add of mucilage, 1/4 oz.; previously rubbed with sap green or syrup of buckthorn, q. s. to colour. The linen must be first moistened with ‘liquid pounce,’ or ‘the preparation,’ as it is commonly called, and when it has again become dry, written on with a clean quill pen. The ink will bear dilution if the writing is not required very black.

The POUNCE or PREPARATION. A solution of carbonate of soda, 1-1/2 oz.; in water, 1 pint, slightly coloured with a little sap green or syrup of buckthorn, to enable the spots wetted with it to be afterwards known.

2. (WITHOUT PREPARATION.) Take of nitrate of silver, 1/4 oz.; water, 3/4 oz.; dissolve, add as much of the strongest liquor of ammonia as will dissolve the precipitate formed on its first addition, then further add of mucilage, 1-1/2 dr., and a little sap green, syrup of buckthorn, or finely powdered indigo, to colour. Writing executed with this ink turns black on being passed over a hot Italian iron, or held near the fire.

3. Terchloride of gold, 1-1/2 dr.; water, 7 fl. dr.; mucilage, 2 dr.; sap green, q. s. to colour. To be written with on a ground prepared with a weak solution of protochloride of tin, and dried. Dark purple.

4. (Rev. J. B. Reade.) Nitrate of silver, 1 oz., tartaric acid (pure), 3 dr., are triturated together in a mortar in the dry state; a little water is then added, by which crystals of tartrate of silver are formed, and the nitric acid set free; the latter is then saturated with liquor of ammonia, sufficient being added to dissolve all the newly-formed tartrate of silver, avoiding unnecessary excess; lastly, a little gum and colouring matter is added.

5. (Rev. J. B. Reade.) To the last is added an ammoniacal solution of a salt of gold. Mr Reade has used for this purpose the ‘purple of Cassius,’ the hyposulphate, the ammonio-iodide, the ammonio-periodide of gold, but any other compound of gold which is soluble in ammonia will do as well. This ink is unacted on by nearly all those reagents which remove writing executed with solutions of the salts of silver alone, as cyanide of potassium, the chlorides of lime and soda, &c.

6. (Redwood.) Nitrate of silver and pure bitartrate of potassa, of each 1 oz. (or 4 parts), are rubbed together in a glass or Wedgwood-ware mortar, and after a short time liquor of ammonia, 4 oz. (16 parts, or q. s.), is added; when the solution is complete, archil, 4 dr. (or 2 parts); white sugar, 6 dr. (or 3 parts); and powdered gum, 10 dr. (or 5 parts), are dissolved in the liquor, after which sufficient water is added to make the whole measure exactly 6 fl. oz., when it is ready to be bottled for use. The last three are used in the same manner as No. 2.

7. (Dr Smellie.) From sulphate of iron, 1 dr.; vermilion, 4 dr.; boiled linseed oil, 1 oz.; triturated together until perfectly smooth. Used with type.

8. (Soubeiran.) Nitrate of copper, 3 parts; carbonate of soda, 4 parts; nitrate of silver, 8 parts; mix, and dissolve in liquor of ammonia, 100 parts. Used like No. 2.

9. (Ure.) A strong solution of chloride of platinum, with a little potassa, and sugar and gum, to thicken.

10. The fluid contained between the kernel and shell of the cashew nut. On linen and cotton it turns gradually black, and is very durable. This has been called ANACARDIUM or CASHEW-NUT INK.

11. Sulphate of manganese, 2 parts; lampblack, 1 part; sugar, 4 parts; all in fine powder, and triturated to a paste with a little water. Used with types or stencil-plates; the part, when dry, being well rinsed in water. Brown.

12. Black oxide of manganese and hydrate of potassa are mixed, heated to redness in a crucible, and then triturated with an equal weight of pure white clay, and water, q. s. to give it due consistence. Used like the last. (Brown.)

13. (Aniline Black Marking Ink.) This ink is prepared by means of two solutions, one of copper, the other of aniline, prepared as follows:——

(1.) COPPER SOLUTION. 8·52 grams of crystallised chloride of copper, 10·65 grams of chlorate of soda, and 5·35 grams of chloride of ammonium are dissolved in 60 grams of water.

(2.) ANILINE SOLUTION. 20 grams of hydrochlorate of aniline are dissolved in 30 grams of distilled water, and to this are added 20 grams of solution of gum Arabic (1 part of gum to 2 of water) and 10 grams of glycerin.

By mixing in the cold 4 parts of the aniline solution, with 1 part of the copper solution, a greenish liquid is obtained which can be employed directly for the marking; but as this liquid can only be preserved for a few days without decomposition, it is advisable to keep the solution separately, until the ink is required for use.

The ink may be used either with a pen, or a stencil plate and brush; if it do not flow freely from the pen it may be diluted with a little water without fear of weakening the intensity of the colour. At first the writing appears of a pale green colour, but after exposure to the air it becomes black, or it may be changed to a black colour immediately, by passing a hot iron over the back of the fabric, or heating it over the flame of a spirit lamp. As, however, a dry heat is apt to make the fibre saturated with the ink, brittle, it is preferable to hold the marked fabric over a vessel, containing water in full ebullition; the heat of the vapour is sufficient to determine almost immediately, the reaction by which aniline black is formed. After the steaming, the writing should be washed in hot soapsuds, which gives the ink a fine blue shade. The ink is not acted upon by acids or alkalies, and if care be taken that the fibres are well saturated with it, there is no danger of its being removed by washing. (‘Dingler’s Journal.’)

14. In addition to the above formulæ, the following of M. Henry may be worthy of attention in large establishments where economy is an object:——Take 1 oz. of iron filings and 3 oz. of vinegar, or diluted acetic acid. Mix the filings with half the vinegar, and agitate them continually till the mixture becomes thick, then add the rest of the vinegar and 1 oz. of water. Apply heat to assist the action, and when the iron is dissolved, add 3 oz. of sulphate of iron, and 1 oz. of gum previously dissolved in 4 oz. of water; and mix the whole with a gentle heat. To be used with brush and stencil plates.

15. (Crimson Marking Ink.) Dissolve 1 oz. of nitrate of silver, and 1-1/2 oz. of carbonate of soda in crystals, separately in distilled water, mix the solutions, collect and wash the precipitate on a filter, introduce the washed precipitate still moist into a Wedgwood mortar, and add to it tartaric acid 2 dr. and 40 gr., rubbing together till effervescence has ceased; dissolve carmine 6 grains, in liquor ammoniæ (·882) 6 oz., and add to it the tartrate of silver, then mix in white sugar, 6 dr., and powdered gum Arabic, 10 dr., and add as much distilled water as will make 6 oz. (‘Pharm. Journal.’)

_Obs._ The products of the first two of the above formulæ constitute the marking ink of the shops. They have, however, no claim to the title of ‘INDELIBLE INK,’ “which no art can extract without injuring the fabric”——as is generally represented. On the contrary, they may be discharged with almost as much facility as common iron-moulds. This may be easily and cheaply effected by means of ammonia, cyanide of potassium, the chlorides of lime and soda, and some of the hyposulphites, without in the least injuring the texture of the fabric to which they may be applied. The only precaution required is that of rinsing the part in clean water immediately after the operation. The ‘marking ink without preparation’ is more easily extracted than that ‘with preparation.’ The former has also the disadvantage of not keeping so well as the latter, and of depositing a portion of fulminating silver, under some circumstances, which renders its use dangerous. The thinner inks, when intended to be used with type or plates, are thickened by adding a little more gum, or some sugar.

=Ink, Mark′ing.= _Syn._ PACKER’S INK. Ink bottoms. Used by packers for marking bales, boxes, &c.

=Ink, Perpet′ual.= _Prep._ 1. Pitch, 3 lbs.; melt over the fire, and add of lampblack, 3/4 lb.; mix well.

2. Trinidad asphaltum and oil of turpentine, equal parts. Used in a melted state to fill in the letters on tombstones, marbles, &c. Without actual violence, it will endure as long as the stone itself.

=Ink, Print′er’s.= See PRINTING INK.

=Ink, Pur′ple.= 1. A strong decoction of logwood, to which a little alum or chloride of tin has been added.

2. (Normandy.) To 12 lbs. of Campeachy wood add as many gallons of boiling water, pour the solution through a funnel with a strainer made of coarse flannel, or 1 lb. of hydrate, or acetate of deutoxide of copper finely powdered (having at the bottom of the funnel a piece of sponge); then add immediately 14 lbs. of alum, and for every 340 galls. of liquid add 80 lbs. of gum Arabic or gum Senegal. Let these remain for three or four days and a beautiful purple colour will be produced.

=Ink, Red.= _Prep._ 1. Brazil wood (ground), 4 oz.; white-wine vinegar (hot), 1-1/4 pint; digest in glass or a well-tinned copper or enamel saucepan, until the next day, then gently simmer for half an hour, adding towards the end gum Arabic and alum, of each 1/2 oz.

2. Ground Brazil wood, 10 oz.; white vinegar, 10 pints; macerate for 4 or 5 days; then boil as before to one half, and add of roach alum, 4-1/2 oz.; gum, 5 oz.; and when dissolved, bottle for use.

3. As the last, but using water or beer instead of vinegar.

4. Cochineal (in powder), 1 oz.; hot water, 1/2 pint; digest, and when quite cold, add of spirit of hartshorn, 1/4 pint (or liquor of ammonia, 1 oz., diluted with 3 or 4 oz. of water); macerate for a few days longer, and then decant the clear. Very fine.

5. (Buchner.) Pure carmine, 20 gr.; liquor of ammonia, 3 fl. oz.; dissolve, then add of powdered gum, 18 gr. Half a drachm of powdered drop lake may be substituted for the carmine where expense is an object. Colour superb.

6. (Henzeler.) Brazil wood, 2 oz.; alum and cream of tartar, of each 1/2 oz.; rain water, 16 fl. oz.; boil to one half, strain, add of gum (dissolved), 1/2 oz.; and when cold, further add a tincture made by digesting powdered cochineal, 1-1/2 dr., in rectified spirit, 1-1/2 fl. oz.

7. (Redwood.) Garancine and liquor of ammonia, of each 1 oz.; distilled water (cold), 1 pint; triturate together in a mortar, filter, and dissolve in the solution, gum Arabic 1/2 oz.

=Ink, Se′pia.= See SEPIA.

=Ink, Sil′ver.= From silver leaf or powdered silver, as GOLD INK.

=Ink, Sympathet′ic.= _Syn._ DIPLOMATIC INK, INVISIBLE I. Fluids which, when used for writing, remain invisible until the paper is heated, or acted on by some other chemical agent. Sympathetic inks have been frequently employed as the instruments of secret correspondence, and have often escaped detection; but by heating the paper before the fire until it begins to grow discoloured by the heat, the whole of them may be rendered visible.

The following are the most common and amusing sympathetic inks:——1. Sulphate of copper and sal ammoniac, equal parts, dissolved in water; writes colourless, but turns YELLOW when heated.——2. Onion juice; like the last.——3. A weak infusion of galls; turns BLACK when moistened with weak copperas water:——4. A weak solution of sulphate of iron; turns BLUE when moistened with a weak solution of prussiate of potassa, and BLACK when moistened with infusion of galls.——5. The diluted solutions of nitrate of silver and of terchloride of gold; become respectively DARK BROWN and PURPLE when exposed to the sunlight.——6. Aqua fortis, spirits of salts, oil of vitriol, common salt, or saltpetre, dissolved in a large quantity of water; turns YELLOW or BROWN when heated.——7. Solution of chloride or nitromuriate of cobalt; turns GREEN when heated, and disappears again on cooling. If the salt is pure, the marks turn BLUE.——8. Solution of acetate of cobalt, to which a little nitre has been added; becomes ROSE COLOURED when heated, and disappears on cooling.——9. A weak solution of the mixed chlorides of cobalt and nickel; turns GREEN. The last three are about the best of our sympathetic inks.——10. Solution of acetate of lead; turns BROWNISH-BLACK when exposed to the fumes of sulphuretted hydrogen.——11. A weak solution of nitrate of mercury; turned BLACK by heat and sulphuretted fumes.——12. Rice water or decoction of starch; turned BLUE by a solution of iodine in weak spirit, and by the fumes of iodine, if the paper is first slightly moistened by exposure to steam or damp air.

=Ink, Vi′olet.= The same as PURPLE INK, but weaker.

=Ink, Yel′low.= 1. From gamboge (in coarse powder), 1 oz.; hot water, 5 oz.; dissolve, and when cold, add of spirit, 3/4 oz.

2. Boil French berries, 1/2 lb., and alum, 1 oz., in rain water, 1 quart, for half an hour, or longer, then strain and dissolve in the hot liquor gum Arabic, 1 oz.

=Ink, Zinc Labels, to write on.= _Syn._ HORTICULTURAL INK. 1. Dissolve 100 gr. of tetrachloride of platinum in a pint of water. A little mucilage and lamp black may be added.

2. Sal ammoniac 1 dr.; verdigris, 1 dr.; lampblack, 1/2 dr.; water, 10 dr.; mix.

=INK POW′DERS.= _Prep._ 1. Aleppo galls, 4 oz.; sulphate of iron, 1-1/2 oz.; gum Arabic, 1 oz.; lump sugar, 3/4 oz.; (all quite dry and in powder); mix, and divide into 3 packets. A pint of boiling water poured over one of them produces, in a few hours, a pint of excellent ink.

2. Aleppo galls, 3 lbs.; copperas, 1 lb.; gum Arabic, 1/2 lb.; white sugar, 1/4 lb.; all in powder; mix, and divide into two-ounce packets, to be used as the last. Ink powders are very useful in travelling.

=INK STAINS, to remove.= See SPOTS.

=INOCULA′TION.= _Syn._ INOCULATIO, L. In _medicine_ and _surgery_, the application of poisonous or infectious matter to any part of the body for the purpose of propagating a milder form of disease, and thus preventing or lessening the virulence of future attacks. In this country the term is generally restricted to the artificial propagation of smallpox. See VACCINATION.

=INOSIN′IC ACID.= An acid said by Liebig to exist in the juice of the flesh of animals, after it has deposited its kreatine.

=IN′OSITE.= A species of unfermentable sugar, discovered by Scherer in the juice of flesh. It forms beautiful crystals.

=IN′SECTS.= _Syn._ INSECTA, L. A class of invertebrate animals belonging to the subkingdom Annuloso. The true insect is defined as an articulated animal, having six legs, 2 antennæ, 2 compound eyes; a small brain at the anterior extremity of a double medullary cord; its circulation is effected by a pulsating dorsal vessel, provided with numerous valves; its respiration by tracheæ, which form 2 lateral trunks, and ramify through the body. The generation of insects is oviparous. There are two distinct sexes. The adult state is attained through a series of metamorphoses. In general, every insect possesses 2 pairs of wings; the trunk in the adult animal is usually composed of 3 chief parts——the head, thorax, and abdomen. The trunk of an insect may also be described as consisting of 13 segments, of which 1 constitutes the head, 3 constitute the thorax, and 9 the abdomen. Insects are arranged in the following orders:——1. Hymenoptera, including bees, wasps, ichneumon-flies, &c.——2. Coleoptera, including all those kinds commonly called beetles.——3. Neuroptera, dragon-flies, ephemeræ, white ants, &c.——4. Strepsiptera, the stylops, &c.——5. Lepidoptera, the butterflies and moths.——6. Diptera, the house-fly and other 2-winged insects.——7. Orthoptera, crickets, grasshoppers, locusts, earwigs, &c.——8. Hemiptera, bugs, frog-hoppers, aphides, &c.——9. Aptera, fleas, &c. There are several animals belonging to the classes MYRIOPODA and ARACHNIDA which are commonly but erroneously called ‘insects.’ Of these the centipedes, spiders, and acarides, or mites, are well-known examples. Several useful products, as SILK, WAX, HONEY, COCHINEAL, LAC, CANTHARIDES, &c., are supplied by insects. The class includes numerous creatures which are extremely destructive, and others which are regarded as domestic pests. In the articles devoted to these offensive insects various methods of exterminating them are noticed. A powder for destroying insects has recently been introduced into this country, and has been found peculiarly efficacious. This powder, which is known under various names (INSECTS-DESTROYING POWDER, DUMONT’S INSECTICIDE, &c.), is produced by the _Pyrethrum roseum Caucasicum_, a composite flower growing wild in the Caucasus. The central or tubular florets of the disc are alone employed, and when ground, furnish the powder of commerce. This powder, though so destructive to insect life, has no injurious effect upon man or domestic animals. See ACARI, ANT, BEE, BUG, BITES and STINGS, CANTHARIDES, COCHINEAL, LAC, PEDICULI, SILK, &c.

=INSECT′ICIDE POWDER.= See INSECTS.

=INTEM′PERANCE.= Under this head we refer to habitual indulgence in the use of spirituous or fermented liquors, whether accompanied or not by fits of intoxication or drunkenness.

The pernicious influence of intoxicating liquors upon individuals and upon society has been so often and ably exposed by the clergy, judges, and magistrates, and by philanthropists of every kind, that it would be folly to do more than refer to it here. Fully one half of the dark or disreputable deeds of those who fill our gaols, and fully an equal proportion of the poverty and wretchedness which pauperises our population and crowds our workhouses, are traceable to this damning vice of the Anglo-Saxon race——intemperance.

To cure HABITUAL DRUNKENNESS various means have been proposed, most of which are more ingenious than useful. The following, however, deserves respectful notice:——

Dr Kain, an eminent American physician, recommends tartar emetic, given in alterative and slightly nauseating doses, for the cure of habitual drunkenness. “Possessing,” he observes, “no positive taste itself, it communicates a disgusting quality to those fluids in which it is dissolved. These liquors, with the addition of a very small quantity of emetic tartar, instead of relieving, increase the sensation of loathing of food, and quickly produce in the patient an indomitable repugnance to the vehicle of its administration. My method of prescribing it has varied according to the habits, age, and constitution of the patient. A convenient preparation of the medicine is 8 gr., dissolved in 4 oz. of boiling water; 1/2 an oz. (say a table-spoonful) of the solution to be put into half a pint, pint, or quart of the patient’s favorite liquor, and to be taken daily in divided portions. If vomiting and purging ensue” (which is seldom the case), “I should direct laudanum to allay the irritation, and diminish the dose. In some cases the change suddenly produced in the patient’s habits has brought on considerable lassitude and debility, which, however, were of short duration. In a majority of cases no other effect has been perceptible than slight nausea, some diarrhœa, and a gradual but very uniform distaste to the menstruum.”

Dr W. Marcet has described the more or less disordered state of the brain, nerves, muscles, and stomach, brought on by the continual use of alcohol, even without intoxication being produced. The symptoms of this state, which he terms CHRONIC ALCOHOLISM, are quite distinct from those of DELIRIUM TREMENS, which is an acute and violent disturbance of the nervous system. From experiments on a large number of patients, Dr Marcet has arrived at the important conclusion, that oxide of zinc is the true antidote in cases of slow alcoholic poisoning. It seems to act as a strong tonic on the nerves, being at the same time a powerful sedative and antispasmodic.[1]

[Footnote 1: ‘On Chronic Alcoholic Intoxication.’ By W. Marcet, M.D., 1862.]

The symptoms of actual intoxication, or the disordered condition of the intellectual functions and volition, produced by taking excessive quantities of alcoholic liquors, need not be described.

Among the remedies employed to remove the ‘fit of drunkenness,’ the preparations of ammonia, and the vegetable acids, are the most common and important. About 2 or 3 fl. dr. of aromatic spirits of ammonia (spirits of sal volatile), or a like quantity of solution of acetate of ammonia (mindererus spirit), mixed with a wine-glassful of water, will in general neutralise or greatly lessen the action of intoxicating liquors. In some cases these fluids produced vomiting, which is, however, a good symptom, as nothing tends to restore an inebriated person so soon as the removal of the liquor from the stomach. Hence tickling the fauces with the finger or a feather, until sickness comes on, is a method very commonly adopted by drunkards to restore themselves to a sober state. The use of aromatic water of ammonia was first suggested by Mr Bromly. With a like intention, some persons have recourse to soda water, which acts by the free carbonic acid it contains, and also as a diluent and, from its coldness, as a tonic on the coats of the stomach. The carbonates and bicarbonates of soda and potassa are also favourite remedies with habitual drunkards. Among the vegetable acids, acetic acid is the one that appears to possess the greatest power of removing intoxication; and after this follow the citric, tartaric, malic, and carbonic acids. These substances are commonly taken by soldiers before going to parade. The usual dose of vinegar is a small teacupful. In the West Indies lime juice and lemon juice are had recourse to. Both these juices act from the citric acid they contain. The use of bitter almonds, as a means of lessening or retarding the effects of fermented liquors was known to antiquity, and is still common among heavy drinkers at the present day. Even small doses of medicinal prussic acid have been foolishly taken with a like intention. See ABSTINENCE, ALCOHOL, EFFECTS OF, DELIRIUM TREMENS, &c.

=INTERMIT′TENT FEVER.= _Syn._ AGUE. A disease consisting of paroxysms or periods of fever with perfect intermissions or periods without fever. Marsh miasmata, or the effluvia arising from stagnant water or marshy ground, when acted upon by heat, are the most frequent causes of this malady. For the prevention of ague in situations where it prevails endemically, small doses of quinine should be taken two or three times a day, and flannel clothing should be constantly worn.

_Symp._ Each febrile paroxysm is of three periods or stages——the cold, the hot, and the sweating stage, and these occur in regular succession. The cold stage commences with great languor and aversion to motion; a sense of coldness down the back soon follows; then the extremities become cold, the fingers shrunken, and the nails blue; the skin assumes that peculiar condition which is commonly known as ‘goose-skin,’ the patient shivers, his teeth chatter, and he is glad to draw close to the fire or envelop himself in blankets. After this state of things has continued for a greater or less time, the heat of the surface begins to return, the patient has flushings and becomes warmer and warmer, and ultimately the whole surface is of a dry burning heat; intense thirst, restlessness, severe headache, and sometimes delirium, characterise this second or hot stage. After this stage has continued for some time, another change comes over the patient; moisture appears on the face and forehead, the harsh and hot skin becomes soft, and at last a copious sweat breaks out over the whole surface. This is the third or sweating stage, and after it has passed, the several functions of the system return to their ordinary condition. The paroxysm may return daily (QUOTIDIAN AGUE); or every other day (TERTIAN A.); or every fourth day, including that of the first attack (QUARTAN A.).

_Treatm._ During the cold stage everything should be done to bring on the hot; the patient should be placed in a warm bed, with warm pans or bottles of water; he may be allowed the free use of warm diluent drinks. In the hot stage the opposite course should be adopted; the coverings must be diminished and lemonade and other cooling drink administered. In the sweating stage there is no occasion for any treatment beyond care to avoid checking the perspiration by premature exposure. During the intermission the disease must be fought with the tonics, Peruvian bark, or its chief alkaloid, quinine. The most effective form of this remedy is the sulphate, which may be given in doses of from 2 to 4 gr. every three hours, the dose being greater for a quartan than for a quotidian. See AGUE-CAKE, FEVER, &c.

=INTOXICA′TION.= See INTEMPERANCE.

=IN′ULIN.= _Syn._ INULINE, ALANTINE, DAHLINE. A peculiar starch-like substance, first obtained by Rose from the root of _Inula Helenium_ or _elecampane_. It has been found in several other vegetables.

_Prep._ From the rasped root, by the same method that is adopted for arrow-root or potato farina; or by boiling the sliced root in 7 or 8 times its weight of water, and after filtration, whilst hot, allowing the decoction to repose for a short time.

_Prop., &c._ Only very slightly soluble in cold water; very soluble in boiling water, but is nearly all deposited as the solution cools; it is precipitated by alcohol.

Inulin is distinguished from starch by giving a yellow or yellowish-brown instead of a blue colour with iodine; in the decoction not being precipitated by either acetate of lead or infusion of galls; and by the precipitate formed in the cold decoction by an infusion of gall-nuts not disappearing until the liquid is heated to above 212°, whilst the precipitate from starch redissolves at 122° Fahr. It appears to be a substance intermediate between starch and gum.

=I′ODATE′.= _Syn._ IODAS, L. A salt of iodic acid. The iodates closely resemble the chlorates of the corresponding metals. They are recognised by the development of free iodine when their solutions are treated with reducing agents; thus, sulphuretted hydrogen passed into a solution of iodate of potassium reduces this salt to an iodide, iodine being liberated and sulphuric acid and water formed. They deflagrate like the chlorates when heated with combustibles. They are all of sparing solubility, and many are quite insoluble in water. They may be made by adding iodine to soluble hydrates or carbonates, and crystallising the sparingly soluble iodate from the very soluble iodide. See IODIC ACID, IODINE, and POTASSIUM.

=IODHY′DRIC ACID.= See HYDRIODIC ACID.

=IOD′IC ACID.= HIO_{3}. _Syn._ ACIDUM IODICUM, L.

_Prep._ 1. Iodate of sodium is dissolved in sulphuric acid in considerable excess, the solution boiled for 15 minutes, and then set aside to crystallise.

2. Decompose iodate of barium by dilute sulphuric acid.

3. (Boursen.) Iodine, 1 part; nitric acid (sp. gr. 1·5), 40 parts; mix, keep them at nearly the boiling temperature for several hours, or until the iodine is dissolved, then evaporate to dryness, and leave the residuum in the open air at a temperature of about 59° Fahr.; when, by attracting moisture, it has acquired the consistence of a syrup, put it into a place where the temperature is higher and the air drier, when in a few days very fine white crystals of a rhomboidal shape will form.

_Prop., &c._ Iodic acid is a crystalline solid, white or yellowish-white; it is decomposed into oxygen and iodine by a heat of about 450° to 500° Fahr.——a property of which we avail ourselves for the conversion of the salts of this acid (iodates) into iodides. It is very soluble in water, and is rapidly decomposed when heated with inflammable bodies. Iodic acid is used as a test for morphia and sulphurous acid. It has been employed as a tonic, stimulant, and alterative, in catarrhal hoarseness, strumous cases, incipient phthisis, &c.——_Dose_, 3 to 6 gr.

_Test._ When iodic acid is mixed with an equal quantity of an alkaloid (preferably quinine), on a capsule or watch-glass, and a drop or two of water added, several distinct explosions occur, accompanied by the copious evolution of gas. No other substance exhibits a similar reaction. See IODATE.

=I′ODIDE.= _Syn._ IODURET*, HYDRIODATE*, IODIDUM, IODURETUM, HYDRIODAS, L. A compound of iodine with a metal or other basic radical. The iodides belong to the same class of bodies as the bromides and chlorides, and may be, for the most part, made in the same manner. All the principal iodides are noticed under the names of their respective bases. See IODINE, &c.

=I′ODINE.= I. _Syn._ IODUM, B. P.; IODINIUM (Ph. L. & D.), IODINEUM (Ph. E.), L.; IODE, Fr.; IOD, Ger. An elementary substance accidentally discovered in 1812, by De Courtois, a saltpetre manufacturer at Paris. It was first examined and described by M. Clement, in 1813, and its precise nature was soon afterwards determined by Sir H. Davy and M. Gay-Lussac. In 1819, some six years after its discovery, iodine was first employed in pharmacy. The merit of the introduction of this powerful curative agent into medicine is due to Dr Coindet, a physician of Geneva, who in that year commenced a series of experiments upon it as a remedy for bronchocele or goitre. It is found in each of the three kingdoms of nature, but exists in greatest abundance in the vegetable family _Algæ_ (Seaweeds).

_Prep._ Iodine is principally manufactured in the neighbourhood of Glasgow, from the mother-waters of kelp known as iodine lye.

1. Kelp, the half vitrified ashes of seaweed, is exhausted with water, and the solution filtered; the liquid is then concentrated by evaporation until it is reduced to a very small volume, the chloride of sodium, carbonate of sodium, chloride of potassium, and other salts, being removed as they successively assume the crystalline form; oil of vitriol is now added, in excess, to the residual dark-brown mother-liquor (iodine-lye), and the evolved gases are either kindled or allowed to escape by a flue; the liquid, after standing some time, is decanted or filtered, heated to about 140° Fahr., and mixed with as much binoxide of manganese as there was oil of vitriol employed; the whole is then introduced into a cylindrical leaden still, furnished with a very short head and connected with 2 or 3 large globular glass receivers, and heat is applied, when fumes of iodine are evolved and condensed in the receivers. During the distillation very great care is taken to watch the process, and prevent the neck of the still becoming choked with condensed iodine. For this purpose the head of the still is usually furnished with a movable stopper, by which the process may be watched, and additions of manganese or sulphuric acid made, if required. To render the product pure, it should be pressed between blotting paper, and then resublimed in glass or stoneware.

2. A solution of sulphate of copper, 4 parts, and protosulphate of iron, 9 parts, are added to the mother-liquid of the soda-works, as long as a white precipitate is thrown down; this precipitate (iodide of copper) is collected, dried, and mixed with its own weight of finely powdered black oxide of manganese, and distilled by a strong heat in a retort, when dry iodine passes over. By the addition of sulphuric acid with the manganese, a less heat is required, but the product is wet with water, like that of the last formula.

3. The residual liquor of the manufacture of soap from kelp (or other iodine lye), of the sp. gr. of 1·374, is heated to 230° Fahr., with sulphuric acid diluted with half its weight of water, after which the liquor is allowed to cool, and is either decanted or filtered; to every 12 fl. oz. of the filtrate 1000 gr. of black oxide of manganese, in powder, are added; the mixture is put into a glass globe or matrass with a wide neck, over which is inverted another glass globe, and heat is applied by means of a charcoal chauffer, when iodine sublimes very copiously, and condenses in the upper vessel; as soon as the latter is warm, it is replaced by another, and the two globes are thus applied in succession, as long as violet fumes are evolved. The iodine is washed out of the globes with a little cold water. A thin disc of wood, having a hole in its centre, is placed over the shoulder of the matrass, to prevent the heat from acting on the globular receiver. On the large scale, a leaden still, as before described, may be employed, and receivers of either stoneware or glass; and the addition of the sulphuric acid is made in a basin or trough of stoneware or wood. _Prod._ 12 oz. yield 80 to 100 gr.

4. Another method of preparing iodine has been patented by a Mr Stanford, which consists of compressing the wet weed, drying in an oven, and distilling at a high temperature. The inventor claims that double the usual amount of iodine is obtained besides other useful products.

5. Considerable quantities of iodine are now obtained from the mother-liquor of Chilian saltpetre or nitre (nitrate of soda). In 1873, a nitre refinery in Peru which separates the iodine in combination with copper, as cuprous iodide, by means of bisulphide of soda and sulphate of copper, produced 15,000 kilos of cuprous iodide, corresponding to 9000 kilos of iodine.

Other methods of obtaining it from Chilian nitre consist in treating the mother-liquors left after the salt has been crystallised out with sulphurous acid, until the separated iodine begins to redissolve. Nitrous acid has also been substituted for sulphurous. The iodine so procured is purified by sublimation, whilst that which remains in the residual saline matter is removed by treatment with chlorine.

_Prop._ Iodine is usually met with under the form of semi-crystalline lumps having a semi-metallic lustre, or in micaceous, friable scales, somewhat resembling plumbago or gunpowder. By carefully conducted sublimation, or by the slow evaporation of its solution in hydriodic acid, it may be obtained in rhombic plates an inch long. It has a greyish-black colour, a hot acrid taste, and a disagreeable odour not much unlike that of chlorine. It fuses at 225° into a deep-brown liquid, volatilises slowly at ordinary temperatures, boils at 347°, forming a magnificent violet-coloured vapour, when mixed with water it rapidly rises with the steam at 212° Fahr. It dissolves in about 7000 parts of water, and freely in alcohol, ether, solutions of the iodides, liquid hydriodic acid, chloroform, petroleum, bisulphide of carbon, &c. Most of these solutions have the brown colour of liquid iodine, but some (particularly those formed by the last three solvents named above) have the beautiful violet colour of the vapour. It bleaches like chlorine, only more feebly. Iodine has an extensive range of affinity; with the metals it forms compounds termed iodides, of which several are used in medicine. Its principal compounds with oxygen are the iodic and periodic anhydrides. Sp. gr. 4·946 to 4·948. According to Debaugne, the addition of syrup of orange peel or tannin to water greatly increases its power of dissolving iodine. 2 gr. of the latter will enable 6 fl. oz. of water to take 10 gr. of iodine. A knowledge of these facts may prove useful to the pharmaceutist.

_Pur._ It is entirely soluble in rectified spirit, and in a solution of iodide of potassium. On applying heat to it, it first liquefies, and then (wholly) sublimes in violet-coloured vapour. The iodine of commerce is usually that of the first sublimation, and generally contains from 12% to 20% of water. Some of the foreign iodine, prepared by precipitation with chlorine, without subsequent sublimation, even contains 1-4th part of water, and has a dead leaden-grey colour, and evolves a sensible odour of chlorine. Coal, plumbago, oxide of manganese, crude antimony, and charcoal, are also frequently mixed with iodine to increase its weight. Water may be detected by the loss of weight it suffers when exposed to strong pressure between bibulous paper; or more accurately by drying it in the manner directed below,——chlorine may be detected by the odour, and the other substances mentioned above, by their insolubility in rectified spirit and in a solution of iodide of potassium. Before use as a medicine it should be dried by being placed in a shallow basin, of earthenware, in a small confined space of air, with 10 or 12 times its weight of fresh-burnt lime, till it scarcely adheres to the side of a dry bottle, or else prepared from the commercial iodine as follows:——Place it in a deep circular porcelain capsule, and having covered it accurately with a glass matrass filled with cold water, apply a water heat to the capsule for 20 minutes, and then allow the whole to cool; should the sublimate attached to the bottom of the matrass include acicular prism of a white colour, and a pungent odour, it must be scraped off with a glass rod, and rejected; the apparatus is then to be again exposed to a gentle and steady heat until the whole of the iodine has sublimed; the sublimate is, lastly, to be collected from the bottom of the matrass, and at once enclosed in a stoppered bottle.

_Tests._ Free iodine may be recognised by the violet colour of its vapour, by its imparting a violet colour to bisulphide of carbon, and by its striking a blue colour with starch. The latter test is so delicate, that water containing only 1/450000th part of iodine acquires a perceptible blue tinge on the addition of starch. Free iodine may be eliminated from solutions of iodides by chlorine, nitric acid, concentrated sulphuric acid and peroxide of manganese, and may be made evident by adding starch-paste. This reagent serves to detect minute traces of iodine in insoluble as well as in soluble compounds of that element. The substance under examination is mixed in a retort with concentrated nitric acid, and a strip of white cotton cloth moistened with a solution of starch suspended from the stopper; in a few hours the cloth will become coloured blue if the most minute trace of iodine be present. By mixing the liquid containing the iodine with the starch and acid, and lightly pouring thereon a small quantity of aqueous chlorine, a very visible blue zone will be developed at the line of contact, even in very dilute solutions.

Iodides give a pale yellowish precipitate with nitrate of silver, scarcely soluble in ammonia, and insoluble in dilute nitric acid; a bright yellow one with acetate of lead; and a scarlet one with bichloride of mercury. This distinguishes them from the iodates which give white precipitates with the same reagents. In solutions of alkaline iodides, chloride of palladium produces a black precipitate.

_Estim._ The proportion of free iodine in a mixture may be estimated: by separating it by heat, and collecting and weighing the sublimate; by solution in rectified spirit, adding water, and collecting the resulting precipitate, which must then be dried and weighed; by dissolving it in a solution of iodide of potassium, and then adding a standard solution of hyposulphite of sodium, until the whole of the free iodine is taken up, and the mixture no longer strikes a blue colour with starch. 24·8 gr. of the hyposulphite are necessary to absorb 12·7 gr. of free iodine;[2] by comparing the tint of a solution prepared by chloroform with that of a standard solution containing a known quantity of iodine, as in Crum’s process for estimating chlorine.

[Footnote 2: For details of this and other methods of accurately determining the per-centage of iodine, free or combined, the reader is referred to Sutton’s “Systematic Handbook of Volumetric Analysis.”]

_Uses, &c._ Iodine is chiefly used as a medicine, a chemical test, and in photography. Until within the last year it was largely used in the manufacture of the green coal-tar colours; these latter are now chiefly made from anthracene. In small doses it appears to be both alterative and tonic, rapidly diffusing itself through the body, and exerting a stimulating action on the organs of secretion. It is also said to be diuretic, and in some cases to have produced diaphoresis and salivation. Iodine has been exhibited in the following diseases, as well as in most others depending on an imperfect action of the absorbents, or accompanied by induration or enlargement of individual glands or organs:——_Internally_, in bronchocele, goitre, Derbyshire neck, scrofula, ovarian tumours, enlargement or induration of the lymphatic, prostate, and parotid glands, amenorrhœa, leucorrhœa, diseases of the muco-genital tissues, phthisis, chronic nervous diseases, lepra, psoriasis, chronic rheumatism, dropsies, hydrocele, &c.:——_Externally_, in scrofula, numerous skin diseases, (especially the scaly), erysipelas, diseased joints, chilblains, burns, scalds, various wounds, to check ulceration, to promote absorption, &c.——_Dose_, 1/2 gr. dissolved in spirit, or in water by means of an equal weight of iodide of potassium. It is seldom exhibited alone, being usually combined with the last-named substance, which, in fact, is now generally preferred by practitioners. It is applied externally in the form of ointment, solution, or tincture.

=Iodine, Bro′mides of.= Bromine and iodine unite rapidly by mere mixture. By careful distillation a red vapour is obtained, which, on cooling, condenses into red crystals, of a form resembling fern leaves. This is said to be the protobromide (IBr). By adding more bromine, these crystals are converted into a fluid, said to be a pentabromide (IBr_{5}).

=Iodine, Chlo′′rides of.= When dry chlorine is passed over dry iodine, at common temperatures, heat is evolved, and a yellow solid terchloride (ICl_{3}) results when the iodine is fully saturated, and an orange-red liquid protochloride (ICl) when the iodine is in excess. They both absorb moisture in the air, are volatile, and very soluble in water.

=Iodine and Hydrogen.= HYDRIODIC ACID, HI. _Syn._ IODHYDRIC ACID; ACIDUM HYDRIODICUM, L. An acid compound of iodine and hydrogen. _Prep._ 1. (GASEOUS).——_a._ Into a glass tube, closed at one end, introduce a little iodine, then a small quantity of roughly powdered glass moistened with water, next a few small fragments of phosphorus, and upon this some more glass; this order (iodine, glass, phosphorus, glass) is to be repeated until the tube is one half or two thirds filled; a cork and delivery tube are then to be fitted, a gentle heat applied, and the gas collected by ‘downward displacement’ or over mercury. If the gas be passed into water a solution of hydriodic acid will be obtained.

_Obs._ Hydriodic acid gas can only be retained a short time over mercury, owing to its action on that metal.

_b._ Pour a little water over some pentiodide of phosphorus, previously put into a glass retort, apply a gentle heat, and collect the gas as before.

_c._ Heat together in a retort water, iodide of potassium, iodine, and phosphorus, and collect the gas as in _b_.

_d._ Place pure iodide of barium in a retort, and decompose it with sulphuric acid.

2. (SOLUTION OF HYDRIODIC ACID.)——_a._ The gas prepared by either of the above methods passed into cold distilled water.

_b._ Iodine, in fine powder, is suspended in water, and a stream of sulphuretted hydrogen passed through the mixture as long as sulphur is deposited, or until it becomes colourless. The liquid is then gently heated, to expel the excess of sulphuretted hydrogen, and either decanted or filtered. A cheap and excellent process.

_c._ (MEDICINAL HYDRIODIC ACID.) Dr Buchanan.——Tartaric acid, 264 gr.; pure iodide of potassium, 330 gr.; dissolve each separately in 1-1/2 fl. oz. of water; mix the solutions, and when the precipitate has settled decant the clear liquid, and add a sufficiency of water to make it up to 6-1/4 fl. oz. The liquid retains a little acid tartrate of potassium in solution, but this does not interfere with its medicinal properties. This preparation “possesses all the therapeutic powers of iodine without its irritating properties.” (Pereira.)——_Dose_, 1/2 to 1 fl. dr., gradually increased to 2 or 3 fl. dr., twice or thrice daily.

_Prop., &c._ Gaseous hydriodic acid is colourless, fumes in the air, is very soluble in water, and has a density of about 4·4. Liquid hydriodic acid, when strong, is very liable to decompose, and should be kept in well-stoppered bottles. Both the gas and the solution are decomposed by potassium, zinc, iron, and other metals, with the evolution of hydrogen and the formation of salts called iodides.

IODIZED COTTON WOOL. (Mehu.) _Prep._ Finely powdered iodine (5 to 10 per cent.) is strewn upon loose cotton wool in such a manner that the glass jar in which this operation is performed contains alternate layers of cotton wool and iodine. The mixture is gently heated in the open jar on a water bath to expel the air; when this is accomplished the jar is closed and the application of heat continued for about two hours, during which the iodine vapour thoroughly penetrates the wool, imparting to it a yellow colour.

=IODO′FORM.= CHI_{3}. _Syn._ IODOFORMUM, L. A solid, yellow, crystallisable substance, obtained by the action of iodine on alcohol.

_Prep._ 1. An alcoholic solution of potash is added to tincture of iodine, carefully avoiding excess; the whole is then gently evaporated to dryness, the residuum is washed with water, and then dissolved in alcohol; the alcoholic solution yields crystals by evaporation.

2. (Paris Pharmaceutical Society.) Pure carbonate of potash, 2 parts; alcohol (84°) 5 parts; distilled water, 15 parts. The potash, water, alcohol, and the iodine reduced to powder are placed together in a flask, and the whole heated in a water bath until the decoloration of the liquid. Another 1/2 part of iodine is then added and heat again applied, and the addition of the element is repeated until the liquid remains slightly brown coloured. It is then decolorised by the addition of one or two drops of caustic potash solution, and upon cooling crystals of iodoform are obtained.

These are collected upon a filter, washed lightly with cold distilled water, then dried upon blotting paper and enclosed in well-stoppered bottle.

By the evaporation of the mother liquor iodide of potassium is obtained.

_Prop., &c._ Nearly insoluble in water; freely soluble in alcohol; the solution is decomposed by caustic potassa into formic acid and iodide of potassa.——_Dose_, 1/2 gr. to 3 gr. Medicinal applications, the same as those of iodine itself.

=IPECACUAN′HA.= _Syn._ (IPECACUANHA, L.; IPECACUHAN, E., B. P.) RADIX IPECACUANHÆ, IPECACUANHA (Ph. L. E. & D.), L. The dried root of _Cephaëlis Ipecacuanha_, or the true ipecacuanha plant, one of the _Cinchonaceæ_. “Ashy coloured, tortuous, very much cracked, and marked in rings with deep fissures, having an acrid, aromatic, bitterish taste.” (Ph. L.) It occurs in pieces 3 or 4 inches long, and about the size of a writing quill.——_Dose._ As an emetic, 10 to 20 gr., assisted by the copious use of warm water; as a nauseant, 1 to 3 gr.; as an expectorant and sudorific, 1/2 to 1 gr. It is undoubtedly the safest and most useful medicine of its class. It has recently been highly recommended in dyspepsia, combined with other bitters or aperients. Almond meal is sometimes used as an adulterant in ipecacuanha powder.

The following is Bucholz’s analysis of ipecacuanha root:——

Emetic extractive (emetina) 4·13 Soft resin 2·43 Wax 0·75 Gum 25·17 Starch 9·00 Woody fibre 10·80 Bitter extractive 10·12 Sugar 2·00 Extractive, gum and starch } extracted by potash } 34·80 Loss 0·80 —————— 100·00

The annexed process for the determination of the emetina in ipecacuanha is by Zenoffsky:——Take 15 grammes of the root, mix with 15 drops of dilute sulphuric acid, and so much of 85 per cent. alcohol that the volume shall be 155 c.c. Digest 24 hours, filter, measure 100 c.c. of the filtrate, evaporate the alcohol, and add a deci-normal solution of iodo-hydrargyrate of potassium until no more reaction takes place. The number of c.c. of the reagent used multiplied by 0·0189 (1/10000th of an equivalent of emetine) gives the amount of emetine in the 10 grammes of root to which the 100 c.c. of liquid corresponds. The deci-normal solution of iodo-hydrargyrate of potassium is made by dissolving 13·546 grammes of mercuric chloride and 49·8 grammes of potassium iodide in water, and making up to 1 litre.

Quantitative determination showed that one c.c. of such a solution corresponds to 0·0189 gramme of emetine. To perform the volumetric estimation, the standard solution is added to the liquid containing the alkaloid, until no more turbidity is produced. To determine the end of the reaction, filter a few drops on to a watch-glass (placed on black glazed paper) and touch with a glass rod previously moistened with the standard solution. To prevent loss both filter and filtrate should be returned to the liquor.

=IRID′IUM.= Ir. A rare metal discovered by Descotils in 1803, and by Tennant in 1804, in the black powder left in dissolving crude platinum. This powder is an alloy of iridium with osmium. The metal is also found native and nearly pure amongst the Uralian platinum ores.

_Prep._ The native alloy of iridium and osmium remaining after dissolving crude platinum in aqua regia is reduced to powder, mixed with an equal weight of dry chloride of sodium, and heated to redness in a glass tube, through which a stream of moist chloride gas is transmitted. The further extremity of the tube is connected with a receiver containing liquor of ammonia. Chloride of iridium and chloride of osmium are produced; the former remains in combination with the chloride of sodium; the latter, being volatile, is carried forward into the receiver, where it is decomposed into osmic and hydrochloric acids, which combine with the ammonia. The contents of the tube, when cold, are treated with water to dissolve out the double chloride of iridium and sodium; the solution thus formed is mixed with an excess of carbonate of sodium, and evaporated to dryness. The residue is ignited in a crucible, boiled with water, and dried; it then consists of a mixture of sesquioxide of iron and a combination of oxide of iridium with sodium hydrate. It is reduced by hydrogen at a high temperature, and treated successively with water and strong hydrochloric acid, which remove the alkali and the iron, leaving metallic iridium in a divided state. By strong pressure and exposure to a welding heat, a certain degree of compactness may be given to the product.

_Prop., &c._ Brittle, white, very hard, only fusible by the strongest heat of Deville’s gas furnace. In its pure state it is not acted upon by any of the acids, but it is oxidised by fusion and nitre, and by ignition to redness in the air. An ingot of iridium, weighing 27-3/4 oz., melted by Deville’s process, was displayed in Messrs Johnson and Matthey’s case at the International Exhibition of 1862. An alloy of iridium and osmium (artificial or native) has been employed for tipping the nibs of gold pens (everlasting pens).

=Iridium, Chlo′rides of.= DICHLORIDE. IrCl_{2}. An olive-green powder formed by transmitting chlorine over powdered iridium, heated to a dull red, or by digesting the hydrated protoxide in hydrochloric acid. SESQUICHLORIDE, Ir_{2}Cl_{6}, obtained by calcining iridium with nitrate of potassium, digesting in nitric acid, washing with water, and solution in hydrochloric acid. TETRACHLORIDE, IrCl_{4}, obtained in solution by adding hydrofluosilicic acid to the tetrachloride of iridium and potassium (formed when chloride is passed over a heated mixture of iridium and chloride of potassium). HEXACHLORIDE, IrCl_{6}, obtained in combination with potassium by heating iridium with nitrate of potassium, dissolving in aqua regia, and evaporating to dryness.

=Iridium, Ox′ides of.= MONOXIDE, IrO, prepared by adding potassium hydrate to the hexachloride of iridium, and digesting the precipitate in an acid. It is a heavy black powder, insoluble in acid. SESQUIOXIDE, Ir_{2}O_{3}, is best prepared by fusing in a silver crucible a mixture of carbonate of potassium and the double chloride of iridium and potassium, and boiling the product in water. Bluish-black TRIOXIDE, IrO_{3}, is produced when carbonate of potassium is gently heated with hexachloride of iridium. A greyish-yellow hydrate, containing alkali.

=IRITIS.= A very dangerous disease of the eye, producing inflammation in the iris or coloured circle which surrounds the pupil. Iritis is frequently produced by rheumatism, as well as by scrofula and gout, and often places the sight in great peril.

The symptoms are pains around the ball of the eye and on the brow, which increase at night, cloudiness of the cornea, difficulty, and inequality of contraction in the pupil, change of colour in the iris, frequently disturbed vision, and much pain in and watering from the eye when the patient is placed in the light, particularly a strong light.

We have described the principal symptoms of this serious disorder in order that any one affected by them may at once seek the assistance of a skilful surgeon or oculist.

=I′RON.= Fe. _Syn._ FERRUM, L.; FER, Fr.; EISEN, Ger. The history of this most important metal extends to the remote past. The discovery of an iron rod in one of the Assyrian bronzes brought to England by Mr Layard established the interesting fact that this metal was known and commonly employed, where strength was required, nearly 3000 years ago. Rust of iron and scales of iron were used as medicines at a period equally remote.

_Sources._ Iron in a metallic state (native iron) is of very rare occurrence; but it invariably enters into the composition of meteorites. Combined with oxygen and other elements, as iron ores, it occurs in nearly every part of the earth. These ores may be divided into the oxides and the carbonates. The oxides may be again divided into four distinct classes, viz.——(1) Magnetic iron ore, consisting of 31% protoxide and 69% sesquioxide, with an insignificant proportion of silica; (2) specular iron, or iron glance, composed of the sesquioxide, with a small admixture of magnetic oxide; (3) red hæmatite, consisting of the sesquioxide nearly in a state of purity; and (4) brown hæmatite, the hydrated sesquioxide of iron. The carbonates are principally two, viz.——(5) spathose iron, the protocarbonate of iron in a sparry condition, and (6) clay ironstone or black band ironstone, which consists of the protocarbonates associated with clay and carbonaceous matter.

Swedish iron is made almost entirely from No. 1, which occurs in massive beds at Arendahl and Dannemora, in Sweden. This iron is of great purity, being perfectly free from sulphur and phosphorus. The titaniferous iron sand found at Taranaki, in New Zealand, consists almost entirely of No. 1 and the metal titanium. No. 2 found principally in the island of Elba, in the form of rhombohedral crystals. The micaceous iron ore found in small quantities in Wales and Lancashire has nearly the same composition, but crystallises in brilliant plates. No. 3 occurs in radiated fibrous masses in different parts of the world. It is found in large quantities in Wales and Lancashire, some of the specimens from the latter locality containing nearly 99% of the sesquioxide. It makes excellent iron. No. 4 occurs in reddish-brown masses of a botryoidal form. It is a valuable ore, and is found in England, Wales, and Scotland. No. 5 is found chiefly at Siegen, in Prussia. No. 6 is the principal ore of the Staffordshire and Scotch iron districts, where it occurs in great abundance, associated with the fuel and the flux required for smelting it. Iron is contained in plants, and forms an essential component of the blood of the higher animals.

_Prep., &c._ Iron is only prepared on the large scale, and an account of the manufacture would be out of place here. Those requiring detailed information must consult the elaborate works of Percy, Hunt, Fairbairn, Phillips, and other metallurgists.

Pure iron may be prepared by introducing fine iron wire, cut small, 4 parts, and black oxide of iron, 1 part, into a Hessian crucible; covering with a mixture of white sand, lime, and carbonate of potassium (in the proportions used for glass-making); and, after applying a closely fitting cover, exposing the crucible to a very high degree of heat. A button of pure metal is thus obtained, the traces of carbon and silicon present in the wire having been removed by the oxygen of the black oxide.

_Prop., &c._ The properties and uses of iron are too well known to require description. Its applications are almost universal. It is remarkably ductile, and possesses great tenacity, but is less malleable than many of the other metals. Its sp. gr. is 7·844. It is the hardest of all the malleable and ductile metals, and when combined with carbon (steel) admits of being tempered to almost any degree of hardness or elasticity. In dry air it does not oxidise at common temperatures; but at a red heat it soon becomes covered with a scaly coating of black oxide, and at an intense white heat burns brilliantly with the production of the same substance. Pure water, free from air or carbonic acid, does not tarnish the surface of polished iron, but the combined action of air and moisture, especially when a little acid vapour is present, causes its surface to be soon covered with rust, which is hydrated sesquioxide of iron (ferric hydrate). Nearly all acids attack iron; dilute sulphuric and hydrochloric acid do so with considerable energy and the evolution of hydrogen gas. At a red heat iron decomposes water rapidly, hydrogen being evolved, and the black oxide of iron formed. Iron is magnetic up to a dull-red heat, at which point it loses all traces of that property. It melts at about 3300° Fahr. With oxygen, chlorine, iodine, the acids, &c., it forms numerous important compounds. As a remedial agent, when properly exhibited, iron acts as a genial stimulant and tonic, and generally proves beneficial in cases of chronic debility, unaccompanied with organic congestion or inflammation. The carbonate (ferrous carbonate), as it exists in mineral waters, held in solution by carbonic acid in excess, appears to be the form most congenial to the human body; and from its state of dilution is rapidly absorbed by the lacteals, and speedily imparts a ruddy hue to the wan countenance. Iron is undoubtedly one of the most valuable articles of the materia medica, and appears from the antiquity of its introduction into medicine, and the number of its preparations, to have been deservedly appreciated.

_Tests._ Iron forms two classes of salts, namely, ferrous or proto salts, in which iron exhibits a power of combining with two atoms of any monad element, and the ferric or persalts in which iron has a capacity of uniting with three atoms of any monad element.

The ferrous or proto salts have generally a greenish colour, but yield nearly colourless solutions, except when concentrated. Their solutions are known by the following reactions:——They are not precipitated by hydrosulphuric acid when acid, and but incompletely when neutral. Sulphide of ammonium produces a black precipitate, becoming brown on exposure to the air, insoluble in alkalies, but easily soluble in the mineral acids. Ammonia and potassa give a greenish-white precipitate, gradually becoming green and then brown in the air. This precipitate occasionally is of a bluish-black if excess of potassa is used. The presence of ammoniacal salts interferes with the action of these tests. Ferrocyanide of potassium gives a nearly white precipitate, becoming gradually blue in the air, and immediately so on the addition of a little weak nitric acid or chlorine water. Ferricyanide of potassium produces a rich deep-blue precipitate, insoluble in hydrochloric acid. In highly dilute solutions the effect is only a deep bluish-green coloration. Phosphate of sodium produces a white precipitate, which after a time becomes green.

The ferric salts, which are also called the sesqui or persalts of iron, have for the most part a reddish-yellow colour, yielding deep-coloured solutions, which exhibit the following reactions:——They redden litmus paper. Hydrosulphuric acid in acid solutions reduces ferric to ferrous salts, giving a white or yellow precipitate of sulphur only. In alkaline solutions it yields a blackish precipitate, consisting of sulphur and ferrous sulphide. Sulphide of ammonium gives similar reaction. Ammonia and potassa produce bulky reddish-brown precipitates insoluble in excess. Ferrocyanide of potassium gives a rich blue precipitate, insoluble in hydrochloric acid, and readily decomposed by potassa. Ferricyanide of potassium deepens the colour, but does not give a blue precipitate, as it does with ferrous salts (proto salts). Sulphocyanide of potassium gives an intense ruby-red colour to neutral or acid solutions. Tincture and infusion of galls strike a black colour. Phosphate of sodium gives a white precipitate, which becomes brown, and finally dissolves on the addition of ammonia.

_Estim._ The iron may be thrown down in the state of ferric hydrate or hydrated sesquioxide, washed, dried, ignited, and weighed. The weight, in grains, multiplied by ·7, indicates the weight of metallic iron.

Fifty gr. of the ore are reduced to powder, dissolved in aqua regia, with the aid of heat, and the solution filtered in order to separate the silica and a little alumina which sometimes is left in an insoluble state; an excess of ammonia is then added to the filtered liquor, which produces a reddish-brown precipitate of ferric hydrate mixed with alumina which is collected on a filter, washed, and boiled with a solution of potassa, in order to dissolve the alumina; the whole is next thrown upon a filter, washed, dried, carefully ignited, and weighed. The above is well adapted to determine the quantity of iron in clay ironstone, the most common ferruginous ore in England.

The sulphur in cast and wrought iron, and steel, may be estimated by the following process, invented by M. Koppmayer:——10 grammes of iron, finely produced and sifted, are introduced into a bottle holding from 1/2 to 1/3rd litre. The stopper has three holes. Through one of these passes a funnel with a ground-glass tap, its neck reaching to the bottom of the bottle. Through the second passes the tube at right angles, fitted with a tap and reaching also to the bottom of the bottle.

Through the third hole passes a delivery tube, connecting the bottle to the condensing apparatus.

This latter consists of a series of bulbs arranged like a staircase, so as to permit the gas to come into the greatest possible contact with the standard solution of iodine in iodide of potassium, with which the condenser is filled, this solution ought not to be exposed to light.

When the apparatus is arranged as above, the atmospheric air is first driven out of the bottle by means of a current of hydrogen gas, introduced by the tube bent at right angles. When it is considered that the air is entirely expelled, the tap of this tube is closed. The funnel is now filled with hydrochloric acid, its tap is opened, and by means of the application of heat the acid is allowed to run down upon the iron without allowing any common air to enter. Hydrogen and sulphuretted hydrogen are formed which pass into the condenser.

Acid is thus added until all disengagement of gas ceases. The bottle is then heated till its contents boil, a little water having been first added by means of the funnel. After these operations, hydrogen is allowed to enter anew to sweep out all remaining gases. The iodised solution is then poured out, care being taken to rinse the bulb-tube thoroughly, and titrated with hyposulphite of soda, so as to find the remaining proportion of free iodine. The difference between the original amount of free iodine present in the solution, and the amount thus found, shows the proportion of iodine which has been converted into hydriodic acid, and which is proportional to the sulphur contained in the sample under examination.

=Iron, Preparations of=:——

=Ferric Acetate.= Fe_{2}(C_{2}H_{3}O_{2})_{6}. _Syn._ PERACETATE OF IRON; FERRI SESQUIACETAS, L. _Prep._ Ferric carbonate, 1 part; acetic acid, 6 parts; digest three days and filter. A dark brownish-red, uncrystallisable liquid, very soluble and powerfully astringent. The calcined sesquioxide of iron of the shops, commonly sold as carbonate of iron, does not answer well for this or any of the sesqui-compounds, owing to its being with difficulty dissolved by acids, especially by the weaker ones.——_Dose._ (Of the last) 10 to 25 drops, in water or wine.

=Ferric Albuminate.= _Syn._ FERRI ALBUMINAS, L. _Prep._

Precipitate a filtered solution of white of egg with another of ferric sulphate or persulphate of iron, wash the deposit in water, and dissolve it in alcohol holding potassium hydrate in solution.

This preparation is highly spoken of by M. Lassaigne as especially adapted by its nature, on theoretical grounds, for combining with the tissues of the body.

=Ferric Citrate.= Fe_{2}(C_{6}H_{5}O_{7})_{2}. _Syn._ PERCITRATE OF IRON, CITRATE OF SESQUIOXIDE OF I., CITRATE OF I.; FERRI CITRAS.

_Prep._ By saturating a solution of citric acid in an equal weight of water with freshly precipitated moist hydrated ferric hydrate, evaporating at 150° Fahr. to the consistence of a syrup, and spreading on glass plates to dry.

By either of the methods adopted for the AMMONIO-CITRATE, merely omitting the addition of the ammonia. It much resembles the ammonio-citrate, but is only slightly soluble in water, and has a rather less agreeable taste.——_Dose_, 3 to 5 gr.

=Ferric and Ammonium Citrate.= _Syn._ AMMONIO-CITRATE OF IRON: AMMONIO FERRIC CITRATE; FERRI AMMONIO CITRAS. L. There are several preparations in which the term ‘citrate of iron’ has been applied. That commonly known under this name is really a double citrate of iron and ammonia, and appears to be correctly called ‘ammonio-citrate of iron.’

B. P. Liquor Ferric Persulphatis (B. P.), 8; liquor ammonia, 19-1/2; citric acid (in crystals) 4; distilled water, a sufficiency, mix 14 of the solution of ammonia, with 40 of water, and all gradually; the solution of ferric sulphate stir constantly and briskly; let the mixture stand two hours, and put into a calico filter and allow to drain. Wash well the precipitate until it no longer gives a precipitate with barium chloride. Dissolve the citric acid in 8 oz. of the water, and having applied the heat of a water bath add the precipitate of ferric hydrate previously well drained, stir them together until the whole or nearly the whole of the hydrate has dissolved. Let the solution cool, then add 5-1/2 of the ammonia, filter through flannel, evaporate to the consistency of syrup, and dry it in thin layers on flat porcelain or glass plates at a temperature not exceeding 100°.

_Prep._ (Ph. L.) Ferrous sulphate, 12 oz.; carbonate of sodium, 12-1/2 oz.; dissolve each separately in boiling distilled water, 6 pints; mix the solutions whilst still hot, and allow the precipitate to subside; after a time decant the supernatant liquor, wash the precipitate frequently with water (drain it), add of citric acid (in powder), 6 oz., and dissolve by the aid of a gentle heat; when the whole has cooled, add of liquor of ammonia, Ph. L., 9 fl. oz., and gently evaporate to the consistence of a syrup; in this state spread it very thinly on flat earthenware dishes (or sheets of glass), dry by a gentle heat, and when dry keep it in well-stoppered bottles.

(Ph. D.) Citric acid, 4 oz.; distilled water, 16 fl. oz.; hydrated ferric oxide, obtained from the sulphate, 5 oz.; liquor of ammonia, 4 fl. oz., or q. s.

(Wholesale.) A mixture of iron filings and citric acid, in powder, with barely sufficient water to cover it, is kept in a warm situation for some days, occasionally stirring the mass, and replacing the water as it evaporates. A saturated solution is next made in distilled water, there being previously added more citric acid (about half the weight of the acid first used), as required; it is then neutralised with liquor of ammonia (about 1-1/4 oz. of liquor of ammonia, sp. gr. ·882, to every gallon of the solution of sp. gr. 1·025), and the solution is concentrated by evaporation; the process is then completed as in No. 1. The first part of this process produces a salt of the protoxide of iron, or ferrous citrate, which is afterwards converted, by exposure to the atmosphere, into a citrate of the magnetic acid, or ferri, ferro-citrate, and, lastly, into citrate of peroxide of iron, or ferric citrate.

B. P. Liquor Ferri Persulphatis 8. Liquor ammoniæ 19-1/2. Citric acid (in crystals) 4. Distilled water, a sufficiency. Mix 14 of the solution of ammonia with 40 of water, and add gradually the solution of ferric sulphate. Stir constantly, let the mixture stand 2 hours and filter through calico, and allow to drain. Wash until the washing ceases to precipitate barium chloride, dissolve the citric acid in 8 of water, add the precipitated ferric hydrate, and heat in a water bath until dissolved. Let the solution cool, add 5-1/2 of the ammonia, filter through flannel, evaporate to the consistency of syrup, and dry on flat porcelain plates in thin layers at a temperature below 100° F.

_Obs._ Pharmaceutical writers have been so diffuse in their disquisitions on the preparation of this salt, as would lead to the inference that there is some difficulty attending it. The contrary is, however, the case. The only care necessary is to spread the syrup solution very thinly on warm sheets of glass to dry, which it will rapidly do if they are placed in an atmosphere of warm dry air, for which purpose a ‘drying closet’ is the most convenient. The dry salt may then be easily detached from the glass, and will form thin scales, or lamellæ, of great brilliancy and beauty. It is also better to use a little more oxide than the acid will dissolve, as the remainder will be employed in a future operation. Less water may be used, or even a larger quantity than that mentioned; but in the first case the liquid will become difficult to filter——in the latter it will require more evaporation. Boiling water dissolves about twice its weight of citric acid, and there remains 13/20ths of this quantity in solution when cold, and it takes rather more than twice the weight of the citric acid in moist hydrated protoxide of iron to produce saturation.

_Prop., &c._ This beautiful salt is of a rich ruby colour, and forms glistening transparent scales, very soluble in aqueous menstrua, and the resulting solution is less easily decomposed by reagents than the solutions of most of the other salts of iron. It is ‘compatible’ with the alkaline of carbonates and bicarbonates, and several other salts, and is nearly tasteless, advantages which have been perhaps overrated by both prescriber and patient. It is doubtful whether this article has not obtained a larger sale from its pleasing appearance than from its medicinal virtues. Several persons who have prepared it in lumps or powder, by the simple evaporation of the solution to dryness, have been unable to sell it under that form, even at a lower price.

Ammonio-citrate of iron is soluble in water; the solution neither changes the colour of litmus nor turmeric; nor is it turned blue by ferrocyanide of potassium; but either potassium hydrate or lime water being added, it throws down ferric hydrate, and ammonia is evolved. From 100 gr. dissolved in water, potassium hydrate precipitates about 34 gr. of ferric hydrate.——_Dose_, 3 to 10 gr., in water, wine, or bitter infusions.

=Ferric and Strychnine Citrate.= (U. S.) _Syn._ FERRI ET STRYCHNIÆ CITRAS. _Prep._ Citrate of iron and ammonia, 500 gr.; strychnia, 5 gr.; citric acid, 5 gr.; distilled water, 9 fl. dr. Dissolve the citrate of iron and ammonia in 1 oz. of the water, and the strychnia and nitric acid in 1 dr. of distilled water. Mix the two solutions, evaporate the mixture over a water bath, at 140° Fahr., to the thickness of a syrup, and spread on glass plates, so that the salt, when dry, may be obtained in scales.

=Ferric and Magnesium Citrate.= _Syn._ CITRIC OF IRON AND MAGNESIA; FERRI MAGNESIO CITRAS; FERRI ET MAGNESIÆ CITRAS, L. _Prep._ As the last, but using carbonate of magnesium instead of ammonia to neutralise the solution.——_Dose_, 2 to 10 gr. It has been recommended as a chalybeate in the dyspepsia of gouty and debilitated habits.

=Ferric and Quinine Citrate.= _Syn._ CITRATE OF QUININE AND IRON; FERRI-QUINIO-CITRAS, L. As the ammonio-citrate, but using quinine, recently precipitated, instead of ammonia, to neutralise the acid.

B. P. Pure ferric hydrate is prepared from liquor ferri persulphatis, 4-1/2 pints, and liquor ammoniæ, 8 pints, as in the ferric and ammonium citrate. Sulphate of quinine 1 is mixed with water 8, and sulphuric acid 1-1/2, and when dissolved, ammonia added until the quinine is precipitated. The precipitate is collected and washed with 30 of water. Citric acid 3 is dissolved in 8 of water by the aid of a water bath, and the ferric hydrate, well drained, added; stir together until dissolved, and add the quinine, stirring well until all is dissolved, and allow to cool; add 1-1/2 of solution of ammonia diluted with 2 of water, stirring the solution briskly until the quinine at first thrown down by the ammonia is redissolved; filter and evaporate to a syrup, drying in thin layers on flat porcelain or glass plates at a temperature of 100°.

Ferric citrate, 4 parts; citrate of quinine, 1 part; distilled water, q. s.; dissolve, gently evaporate, and proceed as directed for ammonio-citrate of iron. Greenish golden-yellow scales when prepared by the B. P. process, soluble in 2 parts of water, and somewhat deliquescent; entirely soluble in ether; taste bitter as well as chalybeate.——_Dose_, 2 to 6 dr.; in cases where the use of both iron and quinine is indicated.

=Ferric and Sodium Citrate.= _Syn._ FERRI SODIO-CITRAS, FERRI ET SODÆ CITRAS, L. _Prep._ From citric acid, carbonate of sodium, and iron or the hydrate, as the ammonio-citrate or potassio-citrate.

=Ferric Chlo′ride.= Fe_{2}Cl_{6}. _Syn._ SESQUICHLORIDE OF IRON, PERCHLORIDE OF IRON, PERMURIATE OF I.; FERRI SESQUICHLORIDUM, L. _Prep._ 1. (Anhydrous.) By passing dry chlorine over heated iron filings. Brown scales.

(Hydrated.) Dissolve ferric hydrate in hydrochloric acid, evaporate to the consistence of a syrup, and crystallise. Yellow or red scaly crystals. The impure solution of this salt has been greatly used as a sewage deodoriser. See TINCTURE.

=Ferric and Ammonium Chloride= (Fe_{2}Cl_{6}NH_{4}Cl.Aq). _Syn._ DOUBLE CHLORIDES OF IRON AND AMMONIUM, AMMONIO-CHLORIDE OF IRON; FERRI AMMONIUM CHLORIDUM.

Ferric oxide, 3 oz.; hydrochloric acid, 1/2 pint; digest in a sand bath until dissolved, then add of ammonium 2-1/2 lbs., dissolved in water, 3 pints; filter the liquid, evaporate to dryness, and reduce the mass to coarse powder. Orange-coloured crystalline grains readily soluble in water.

Ammonio-chloride of iron is tonic, emmenagogue, and aperient.——_Dose_, 5 to 15 gr.; in glandular swellings, obstructions, &c.

=Ferric Ferrocy′anide.= (Fe_{4}(FeCy_{6})_{3}. 18Aq). _Syn._ SESQUIFERROCYANIDE OF IRON, PRUSSIAN BLUE; FERRI FERROCYANIDUM, F. SESQUIFERROCYANIDUM, L. _Prep._ Ferrous sulphate, 4 oz.; water, 1 pint; dissolve, add to the solution of nitric acid, 6 fl. dr., in small portions at a time, boiling for a few moments after each addition; next dissolve ferrocyanide of potassium, 4-1/2 oz., in water, 1 pint, and add this last solution, by degrees, to the first liquid, stirring well each time; lastly, collect the precipitate, wash it with boiling water, drain, and dry it.——_Dose_, 3 to 5 gr., three or four times daily, as an alterative, febrifuge, and tonic, gradually increasing the quantity until some obvious effect is produced; in agues, epilepsy, and neuralgia. See PRUSSIAN BLUE.

=Ferric Hydrate.= Fe_{2}(HO)_{6}. See under Ferric Oxide.

=Ferric Iodide.= Fe_{2}I_{6}. _Syn._ FERRI PERIODIDUM, L. _Prep._ Freely expose a solution of ferrous iodide to the air; or digest iodine, in excess, on iron, under water, gently evaporate, and sublime. A deliquescent, volatile red compound, soluble in water and alcohol. It is rarely employed in medicine.

=Ferric Oxide.= Fe_{2}O_{3}. _Syn._ SESQUIOXIDE OF IRON, PEROXIDE OF IRON, RED OXIDE OF I.; FERRI SESQUIOXYDUM, F. PEROXYDUM, F. OXYDUM RUBRUM, L. This substance is found native under several forms, but that employed in the arts is prepared by one or other of the following methods:——

From metallic iron. From iron wire or clean iron filings cut into pieces, moistened with water, and exposed to the air until completely converted into rust; it is then ground with water, elutriated, and dried, in a similar way to that adopted for chalk. For sale, it is usually made up into small conical loaves or lumps.

By calcination:——(BROWN-RED COLCOTHAR, CROCUS, INDIAN RED, ROUGE, JEWELLERS’ R.; FERRI OXYDUM RUBRUM, L.)——Calcine ferrous sulphate until the water of crystallisation is expelled, then roast it with a strong fire until acid vapours cease to rise; cool, wash the residuum with water until the latter ceases to affect litmus, and dry it.

Ferrous sulphate, 100 parts; common salt, 42 parts; calcine, wash well with water, dry, and levigate the residuum. This process yields a cheap and beautiful product, which is frequently sold for the ferri sesquioxydum; but it is less soluble, and therefore unfitted for a substitute for that preparation.

By precipitation;——FERRI SESQUIOXYDUM——B. P., FERRI OXYDUM RUBRUM——Ph. E. L. By precipitating a solution of ferric sulphate or chloride with ammonia, in excess, and washing, drying, and igniting in the resulting hydrate. Pure; anhydrous.

Ferrous sulphate, 4 lbs.; sodium carbonate, 4 lbs. 2 oz.; dissolve each separately in water, 3 galls.; mix the solution whilst hot, set the mixture aside, that the precipitate may subside, and subsequently wash and dry it as before. Contains water, and a trace of alkali.

FERRIC HYDRATE, FERRI PEROXYDUM HYDRATUM——(Ph. D., FERRUGO——Ph. E.)——_a._ (Ph. E.) Ferrous sulphate, 4 oz.; sulphuric acid, 3-1/2 fl. dr.; water, 1 quart; mix, dissolve, boil, and gradually add of nitric acid, 9 fl. dr.; stirring well and boiling for a minute or two after each addition, until the liquor yields a yellowish-brown precipitate with ammonia; it must then be filtered and precipitated with liquor of ammonia (fort.), 3-1/2 fl. oz.; rapidly added and well mixed in; collect the precipitate, wash it well with water, drain it on a calico filter, and dry it at a heat not exceeding 180° Fahr. When intended as an antidote for arsenic it should not be dried, but kept in the moist or gelatinous state.

FERRIC PEROXIDE, MOIST (B. P.) _Syn._ FERRI PEROXIDUM HUMIDUM. _Prep._ Mix solution of persulphate of iron (B. P.), 4 fl. oz., with 1 pint of distilled water, and add it gradually to 33 fl. oz. of solution of soda (B. P.), stirring constantly and briskly. Let them stand for two hours, stirring occasionally; then put on a calico filter, and when the liquid has drained away, wash the precipitate with distilled water till what passes through ceases to give a precipitate with chloride of barium. Lastly, enclose the precipitate without drying it in a stoppered bottle, or other vessel, from which evaporation cannot take place.

DRY HYDRATE OF PEROXIDE OF IRON (B. P.). FERRI PEROXIDUM HYDRATUM. Dry the moist peroxide, 1 lb., at a temperature not exceeding 212° Fahr., till it ceases to lose weight. Reduce to a fine powder.——_Dose_, 5 to 30 grains.

_Prop._ Ferric oxide, prepared by precipitation (1, _c_), is an impalpable powder, of a brownish-red colour, odourless, insoluble in water, freely soluble in acids, and possessing a slightly styptic taste, especially when recently prepared. When exposed to heat its colour is brightened, its sp. gr. increased, and it is rendered less easily soluble in acids. The oxide prepared by calcination is darker and brighter coloured, less soluble, and quite tasteless. It has either a scarlet or purplish cast, according to the heat to which it has been exposed. The finest Indian red, or crocus, usually undergoes a second calcination, in which it is exposed to a very intense heat. It is then known as ‘purple brown.’ The best jeweller’s rouge is prepared by calcining the precipitated oxide until it becomes scarlet.

The hydrate is of a yellowish-brown colour, and though it can be dried without decomposition, it requires to be kept in a moist state. It is best preserved in a well-stoppered bottle, filled with recently distilled or boiled water.

_Pur._ Medicinal ferric oxide or sesquioxide of iron (FERRI SESQUIOXYDUM, Ph. L. & D.) is soluble in dilute hydrochloric acid, scarcely effervescing, and is again thrown down by potassa. The strained liquor is free from colour, and is not discoloured by the addition of either sulphuretted hydrogen or ferrocyanide of potassium.

The hydrate (FERRI PEROXYDUM HYDRATUM——Ph. D., FERRUGO——Ph. E.) is entirely and very easily soluble in hydrochloric acid, without effervescence; if previously dried at 180° Fahr., a stronger heat drives off about 18% of water.

_Uses, &c._ The precipitated oxide is employed in medicine as a tonic and emmenagogue, in doses of 10 to 30 gr.; and as an anthelmintic and in tic douloureux, in doses of 1 to 4 dr., mixed up with honey. It is also employed to make some preparations of iron. The calcined oxide is employed as a pigment, as an ingredient in a plaster, &c. The hydrate is used medicinally as a tonic in doses of 10 to 30 gr.; and in much larger, as an antidote in cases of arsenical poisoning.

We are indebted to Bunsen and Berthold for the introduction of this substance as an antidote to arsenic. A table-spoonful of the moist oxide may be given every 5 or 10 minutes, or as often as the patient can swallow it. (Pereira.) When this preparation cannot be obtained, rust of iron or even the dry so-called carbonate (sesquioxide) may be given along with water instead. According to Dr Maclagan, 12 parts, and to Devergie, 32 parts, of the hydrate are required to neutralise 1 part of arsenious acid. Fehling says that the value of this substance as an antidote to arsenic is materially impaired by age, even when kept in the moist state. The presence of potassium, sodium, ammonium, hydrates, sulphates, chlorides or carbonates, is not of consequence, and, therefore, in cases of emergency, time need not be lost in washing the precipitate, which, in such cases, need only be drained and squeezed in a calico filter. The magma obtained by precipitating ferrous sulphate with magnesia, in excess, and which contains free magnesia and magnesium sulphate, besides ferric hydrate, precipitates arsenious acid not only more quickly, but in larger quantity, than ferric hydrate does when alone. It will even render inert Fowler’s solution, and precipitate both the copper and arsenic from solutions of Schweinfurt green in vinegar, which the pure gelatinous oxide alone will not do.

=Soluble Saccharated Oxide of Iron.= (G.) _Syn._ FERRUM OXYDATUM SACCHARATUM SOLUBILE. _Prep._ Solution or perchloride of iron (sp. gr. 1·480), 2 oz. (by weight); syrup, 2 oz. (by weight); mix, and add gradually, solution of caustic soda (sp. gr. 1·330); 4 oz. (by weight); and set aside for 24 hours; then add to the clear liquid 30 fl. oz. of distilled hot water; agitate and set aside. Pour off the supernatant liquid from the precipitate which will have formed, and pour on fresh distilled water; then collect the precipitate on a filter and wash thoroughly with distilled water.

Put the drained precipitate into a porcelain vessel, and mix with it 9 oz. of sugar in powder, and evaporate to dryness with constant stirring over a water bath, then mix in enough sugar in powder to make up 10 oz. by weight; reduce to powder and keep in a closed vessel. One hundred parts contain three of metallic iron.

=Ferric Nitrate.= Fe_{2}(NO_{3})_{6}. _Syn._ PROTO NITRATE OF IRON, NITRATE OF SESQUIOXIDE OF IRON; FERRI PERNITRAS, L. By digesting nitric acid (diluted with about half its weight of water) on iron or ferric hydrate. A deep-red liquid, apt to deposit a basic salt. It is used in dyeing, and has been recommended in dyspepsia, calculous affections, and chronic diarrhœa.——_Dose_, 5 to 10 or 12 drops.

=Ferric Phosphate.= Fe_{2}H_{3}(PO_{4})_{3}. _Syn._ FERRIC ORTHOPHOSPHATE (Odling); FERRI SESQUIPHOSPHAS, PHOSPHAS FERRICUS, L. A white powder obtained by precipitating ferric chloride by sodium phosphate.——_Uses_ and _dose_. As the last.

FERRIC PYROPHOSPHATE. Fe_{6}(P_{2}O_{7})_{3}. A salt containing ferric iron combined with the radical of pyrophosphoric acid.

_Prep._ By precipitating a solution of ferric sulphate with one of pyrophosphate of sodium, taking care to operate at a temperature below 59° Fahr.

_Prop., &c._ A gelatinous precipitate which dissolves with facility in excess of pyrophosphate of sodium. The citrate of ammonium is the most eligible solvent according to M. Robiquet, who first called attention to this salt as a remedial agent.——_Dose_, 5 to 10 gr.

=Ferric Sulphate.= Fe_{2}(SO_{4})_{3}. _Syn._ PERSULPHATE OF IRON, SULPHATE OF SESQUIOXIDE OF IRON; FERRI PERSULPHAS, L. _Prep._ By adding to a solution of ferrous sulphate exactly half as much sulphuric acid as it already contains, raising the liquid to the boiling-point, and then dropping in nitric acid, until the liquid ceases to blacken by such addition. The solution evaporated to dryness furnishes a buff-coloured mass, slowly soluble in water.

_Prop., &c._ With the sulphates of ammonium and potassium it unites to form compounds to which the name ‘iron alums’ has been given. It forms the active ingredient in the ‘liquor oxysulphatis ferri’ of Mr Tyson, and is said by Dr Osborne to be a constituent of ‘Widow Welch’s pills.’ This salt is also formed when ferrous sulphate is calcined with free exposure to the air. Dissolved in water, it is used as a test for hydrocyanic, gallic, and tannic acids.

=Ferric Sulphide.= _Syn._ PERSULPHIDE OF IRON. This compound is prepared in the hydrated state (FERRI PERSULPHURETUM HYDRATUM) by adding, very gradually, a neutral solution of ferric sulphate to a dilute solution of potassium sulphide, and collecting, &c., the precipitate, as in the case of the hydrated ferrous sulphide. Proposed by Bouchardat and Sandras as a substitute for ferrous sulphide, to which they say it is preferable.

=Ferric Tan′nate.= _Syn._ FERRI TANNAS, FERRUM TANNICUM, L. _Prep._ From tannin, 1 part; boiling water, 150 parts; dissolve, add of freshly precipitated ferric hydrate (dried at 212° Fahr.), 9 parts; evaporate by a gentle heat to one half, filter, add of sugar 1 part, complete the evaporation, and at once put it into bottles.——_Dose_, 3 to 5 gr., thrice daily; in chlorosis, internal hæmorrhages, &c.

Double Ferric and Ammonium Tartrate. _Syn._ AMMONIO TARTRATE OF IRON, DOUBLE TARTRATE OF IRON AND AMMONIUM; AMMONIO FERRIC TARTRATE, FERRI AMMONIO TARTRATE; FERRI AMMONIO TARTRAS.

_Prep._ (Aikin.) Tartaric acid, 1 part; iron filings, 3 parts; digest in a sufficient quantity of hot water to barely cover the mixture for 2 or 3 days, observing to stir it frequently, and to add just enough water to allow the evolved gas to escape freely; next add ammonia, in slight excess, stir well, dilute with water, decant, wash the undissolved portion of iron, filter the mixed liquors, and evaporate to dryness; dissolve the residuum in water, add a little more ammonia, filter, and again gently evaporate to dryness, or to the consistence of a thick syrup, when it may be spread upon hot plates of glass or on earthenware dishes and dried in a stove-room, as directed for the corresponding citrate.

Tartaric acid, 6-1/2 oz.; water, 7 pints; dissolve, neutralise the selection with sesquicarbonate of ammonium, and add 6-1/4 oz. more tartaric acid; to the solution heated in a water bath, further add moist hydrated oxide of iron (obtained from sesquioxide of iron, 53-1/2 dr., dissolved in hydrochloric acid, and precipitated by ammonia); when dissolved, filter, and evaporate, &c., as before.

_Prop., &c._ Glossy, brittle lamellæ, or irregular pieces, of a deep garnet colour, almost black, very soluble in water, and possessing a sweetish and slightly ferruginous taste. By repeated re-solution and evaporation its sweetness is increased, probably from the conversion of a part of its acid into sugar. It contains more iron than a given weight of the sulphate of the same base. It is the most pleasant-tasted of all the preparations of iron except the ammonio-citrate, last noticed.——_Dose_, 3 to 10 gr.

=Ferric and Potassium Tartrate.= _Syn._ TARTRATE OF POTASSA AND IRON, FERRO-TARTRATE OF POTASSA; FERRIC TARTRATE OF P.; FERRI TARTARATUM (B. P.), FERRI POTASSIO-TARTRAS (Ph. L.), FERRUM TARTARIZATUM (Ph. E.), FERRI TARTARUM (Ph. D.), FERRI ET POTASSÆ TARTRAS (Ph. U. S.), L. _Prep._ (B. P.) Prepare ferric hydrate from 4 fl. oz. of liq. ferri persulphas, B. P., as in making the double citrate, and add it to 2 oz. of the acid tartrate of potassium, dissolved in 30 oz. of water. Digest for 6 hours at 140°, allow to cool, and decant off the clear solution, which is to be evaporated down and dried on glass plates.——(Ph. L.) Ferrous sulphate, 4 oz., is dissolved in water, 1 pint, previously mixed with sulphuric acid, 1/2 fl. oz.; heat is applied to the solution, and nitric acid, 1 fl. oz., gradually added; the solution is boiled to the consistence of a syrup, and then diluted with water, 4 galls. (less the pint already used); liquor of ammonia, 10 fl. oz., is next added, and the precipitate washed, and set aside for 24 hours; at the end of this time, the water being decanted, the still moist precipitate is added, gradually, to a mixture of bitartrate of potassium, 2 oz., and water, 1/2 pint, heated to 140° Fahr.; after a time the undissolved oxide is separated by a linen cloth, and the clear solution either gently evaporated to dryness or treated in the same manner as the citrate (lastly, preserve it in well-stoppered bottles). The formulæ of the Ph. E., D., & U. S., are essentially the same. The Ph. D. orders a heat not beyond 150° Fahr. to be applied to the mixture of the oxide and bitartrate, with occasional stirring for 6 hours, and the desiccation to be conducted at the same temperature.

_Obs._ This preparation is a double salt of potassium and iron; it is therefore wrongly called ‘tartrate of iron’ as is commonly heard. It is totally soluble in water; the solution is neutral to litmus and turmeric, unaffected by ferrocyanide of potassium, and not precipitated by acids nor alkalies, nor acted on by the magnet. Heated with potassa, 100 gr. throws down about 34 gr. of sesquioxide of iron. Entirely soluble in cold water; taste freely chalybeate. That of commerce has generally a feebly inky taste a slight alkaline reaction, is slightly deliquescent, dissolves in 4 parts of water, and is nearly insoluble in alcohol.

Potassio-tartrate of iron is an excellent ferruginous tonic.——_Dose_, 10 to 20 gr., made into a bolus with aromatics, or dissolved in water or other convenient menstruum.

=Ferric Valerianate.= _Syn._ VALERIANATE OF SESQUIOXIDE OF IRON, VALERIATE OF IRON; FERRI VALERIANAS (Ph. D.), L. _Prep._ (Ph. D.) By adding a solution of sodium valerianate to another of ferric sulphate, and collecting and washing the precipitate, which is to be dried by placing it for some days folded in bibulous paper, on a porous brick; after which it is to be carefully kept from the air.

_Prop., &c._ A reddish-brown amorphous powder; nearly insoluble in water; soluble in rectified spirit, and in the dilute acids with decomposition. Citrate or tartrate, flavoured with oil of valerian, is frequently sold for it.——_Dose_, 1 to 3 gr.; in anæmia and chlorosis complicated with hysteria.

=Ferroso-Ferric Hydrate.= Fe_{3}(HO)_{6}. _Syn._ HYDRATED FERROSO-FERRIC OXIDE, HYDRATED MAGNETIC OXIDE. (B. P.) Liquor ferri persulphas, 5-1/2; ferri sulphas, 2; solution of soda, 80; distilled water, a sufficiency. Dissolve the ferrous sulphate in 40 of water, add the solution of soda, stirring them well, boil the mixture, let it stand for two hours, put in a calico filter, wash with distilled water until the washing gives no precipitate with barium chloride, and dry at a temperature not exceeding 120.

Ferrous sulphate, 6 oz.; sulphuric acid, 160 minims; nitric acid, 4 fl. dr.; stronger solution of ammonia, 4-1/2 fl. oz.; boiling water, 3 pints; dissolve half of the sulphate in half of the water, add the oil of vitriol, boil, add the nitric acid gradually, boiling after each addition for a few minutes; dissolve the remaining half of the sulphate in the rest of the boiling water; mix the two solutions, add the ammonia, stirring well (and boil for a short time); collect the precipitate on a calico filter, wash it with water until it ceases to precipitate a solution of nitrate of barium, and dry at a heat not exceeding 183° Fahr. The formulæ of Gregory and Dr Jephson are similar.

Ferrous sulphate, 8 oz., dissolved in a mixture of water, 10 fl. oz., and sulphuric acid, 6 fl. dr., is converted by means of nitric acid, 4 fl. dr., diluted with water, 2 fl. oz., into ferric sulphates; this solution is then added to another, formed by dissolving ferrous sulphate, 4 oz., in water, 1/2 pint; the whole is then mixed with liquor of potassium hydrate, 2-3/4 pints, and after being boiled for 5 minutes is collected on a calico filter, and washed, &c., as before; and is to be preserved in a well-stoppered bottle.

_Prop., &c._ The hydrate is a black sand-like substance, consisting of very minute crystals. When pure it is attracted by the magnet, and is entirely soluble in hydrochloric acid; and ammonia added to the solution throws down a black precipitate. The oxide is the chief product of the oxidation of iron at a high temperature in the air and in aqueous vapour. It is more permanent than ferrous oxide, but incapable of forming salts.——_Dose_, 5 to 20 gr. two or three times a day.

=Ferroso-ferric Oxide.= Fe_{3}O_{4}. _Syn._ MAGNETIC O. OF I.; FERRI OXYDUM NIGRUM, F. O. MAGNETICUM (Ph. D.), OXYDUM FERROSO-FERRICUM, L. This occurs native, but that used in medicine is prepared artificially.

From the black scales of iron that fall around the smith’s anvil, by washing, drying, detaching them from impurities by means of a magnet, and then treating them by grinding and elutriation, as directed for prepared chalk. The product of this process is inferior as a medicine to the hydrate obtained as below, being less easily soluble in the juices of the stomach.

=Ferroso-ferric Oxide.= Fe_{3}O_{4}. _Syn._ MAGNETIC OXIDE. See FERROSO-FERRIC OXIDE.

=Iron, Black Oxide of.= (B. P.) _Syn._ FERRI OXYDUM MAGNETICUM; FERRI OXYDUM NIGRUM; MARTIAL ÆTHIOPS. _Prep._ Dissolve sulphate of iron, 2 oz., in 2 pints of distilled water, and add solution of persulphate of iron (B. P.), 5-1/2 fl. oz., then mix with solution of soda, 4 pints (B. P.), stirring well together. Boil the mixture, let it stand for 2 hours, stirring occasionally, then put it on a calico filter, and when the liquid has drained away wash the precipitate with distilled water till what passes through ceases to precipitate chloride of barium. Finally, dry the precipitate at a temperature not exceeding 120° Fahr.——_Dose_, 5 to 10 gr.

=Ferrous Acetate.= Fe(C_{2}H_{3}O_{2})_{2}. _Syn._ FERRI ACETAS, L. _Prep._ 1. From freshly precipitated ferrous carbonate dissolved in dilute acetic acid.

2. By adding a solution of calcium acetate to another of ferrous sulphate, and evaporating the filtered liquid, out of contact with the air. Small, colourless, or pale-greenish needles or prisms, very soluble and prone to oxidation.

=Ferrous Arsenate.= Fe_{3}(AsO_{4})_{2}. _Syn._ FERRI ARSENIAS, L. _Prep._ 1. From a solution of sodium arseniate, added to a solution of ferrous sulphate, the precipitate being collected, washed in a little cold water, and dried.——_Dose_, 1/20 to 1/12 gr., made into a pill; in lupus, psoriasis, cancerous affections, &c. Externally, combined with 4 times its weight of ferrous phosphate and a little water, as a paint to destroy the vitality of cancerous formations. An ointment (20 to 30 gr. to the oz.) is also used for the same purpose. They are all dangerous remedies in non-professional hands.

2. (B. P.) _Prep._ Sulphate of iron, 9 oz.; arseniate of soda dried at 300° F., 4 oz.; acetate of soda, 3 oz. Dissolve the arseniate and the acetate of soda in 2 pints, and the sulphate of iron in 3 pints, of boiling distilled water, mix the two solutions, collect the white precipitate which forms on a calico filter, and wash until the washings cease to be affected by a dilute solution of chloride of barium. Squeeze the washed precipitate between folds of strong linen in a screw-press, and dry it on porous bricks in a warm air-chamber whose temperature shall not exceed 100° F.——Dose, 1/16th of a gr.

=Ferrous Arsenite.= Fe(AsO_{2})_{2}. _Syn._ FERRI ARSENIS, L. From the potassium arsenite, and ferrous sulphate, as the last. A yellowish-brown powder, occasionally used in medicine as a tonic, alterative, and febrifuge.——_Dose_, 1/16 to 1/12 gr.

=Ferrous Bromide.= FeBr_{2}. _Syn._ FERRI BROMIDUM, L. _Prep._ (Moir.) Bromine and iron filings, of each 1 part; water, 3 parts; mix in a stoppered phial, set it aside, occasionally shaking it, for 2 or 3 days, and when the colour of the bromine has disappeared, and the liquid becomes greenish, filter and evaporate to dryness.——_Dose_, 1 to 6 gr., as a tonic, diuretic, and resolvent, in similar cases to those in which iodide of iron is given.

FERROUS CARBONATE. Fe(CO_{3}). _Syn._ PROTOCARBONATE OF IRON; FERRI CARBONAS, F. SUBCARBONAS, L. This occurs in nature as SPATHOSE ORE, the chief constituent as of CLAY IRONSTONE, and in many CHALYBEATE WATERS.

_Prep._ (B. P.) Ferrous sulphate (sulphate of iron), 2; ammonium carbonate, 1-1/4; boiling distilled water, 320; refined sugar, 1. Dissolve the sulphate and ammonium carbonate each in 1/4 of the water, and mix; allow to stand for 24 hours and decant, of the clear solution, add the remainder of the water to the precipitate, stir well, allow to settle, and decant off. Collect the deposit in a calico filter, press, rub in the sugar in a porcelain mortar, and dry at a temperature not exceeding 212° Fahr. Small coherent grey lumps. Precipitate a solution of ferrous sulphate with a solution of sodium carbonate, well wash the green powder with water which has been boiled, and dry it out of contact with the air. On the slightest exposure to air it is converted into ferrous hydrate or oxide. This change is for the most part prevented by combining it with sugar, as in the following preparation.

With sugar: FERRI CARBONAS SACCHARATA, B. P.; SACCHARINE C. OF I.; FERRUM CARBONICUM SACCHARATUM, FERRI CARBONAS CUM SACCHARO——Ph. L., FERRI CARBONAS SACCHARATUM——Ph. E. & D. L.——(Ph. L.) Ferrous sulphate, 4 oz.; sodium carbonate, 4-1/4 oz.; dissolve each separately in quart of boiling water, and mix the solutions whilst hot; after a time collect the precipitate, wash it frequently with water, and add of sugar, 2 oz., previously dissolved in water, 2 fl. oz.; lastly, evaporate the mixture over a water bath to dryness, and keep it in a well-closed bottle.

_Prop., &c._ A sweet-tasted greenish mass or powder, consisting chiefly of carbonate of iron. It is one of the best of the chalybeates.——_Dose_, 5 to 10 gr. When pure, it should be easily soluble in hydrochloric acid with brisk effervescence.

=Ferrous Chloride.= FeCl_{2}. _Syn._ PROTOCHLORIDE OF IRON; MURIATE OF IRON; FERRI CHLORIDUM, L. _Prep._ 1. (Anhydrous.) By passing dry hydrochloric acid gas over ignited metallic iron. The chloride sublimes in yellowish crystals.

2. (Hydrated.) Dissolve iron filings or scale in hydrochloric acid, evaporate and crystallise. Soluble green crystals.

=Ferrous Citrate.= Fe_{3}(C_{6}H_{5}O_{7})_{2}. _Syn._ PROTOCITRATE OF IRON, CITRATE OF PROTOXIDE OF IRON. This salt is easily formed by digesting iron filings or wire with citric acid, and evaporating the solution as quickly as possible out of contact with the air. It presents the appearance of a white powder, nearly insoluble in water, and rapidly passing to a higher state of oxidation by exposure to the air. Its taste is very metallic. It is exhibited under the form of pills, mixed with gum or syrup, to prevent it from being prematurely decomposed.

=Ferrous Ferricy′anide.= _Syn._ FERRIDCYANIDE OF IRON. _Prep._ By adding a solution of potassium ferricyanide (‘red prussiate of potash’) to a solution of ferrous sulphate (or any other soluble ferrous salt), and collecting and drying and precipitate. A bright-blue powder. (See TURNBULL’S BLUE.)

=Ferrous Hydrate.= Fe_{2}(HO)_{2}. See under FERROUS OXIDE.

=Ferrous Hydrate.= Fe(HO)_{2}. May be precipitated from ferrous solutions as a white powder, by alkaline hydrates. It rapidly absorbs oxygen, and turns first green, and then red, by exposure to the air. Both the oxide and hydrate are very powerful bases, neutralising the acids and forming stable salts, which, when soluble, have commonly a pale green colour, and a nauseous metallic taste.

=Ferrous Hypophosphite.= _Syn._ FERRI HYPOPHOSPHIS. From the double decomposition of hypophosphite of lime and sulphate of iron, as hypophosphite of potash.

=Ferrous Iodide.= FeI_{2}. _Syn._ PROTOIODIDE OF IRON, IODIDE OF IRON; F. IODIDUM, FERRI HYDRIODAS, F. IODURETUM, L. _Prep._ (B. P.) Fine iron wire, 1; iodine, 2; distilled water, 10. Introduce the iron, iodine, and 8 of water into a flask, heat it about ten minutes, and boil until all the red colour is gone. Filter through paper into a polished iron dish, washing with the rest of the water, and boil until a drop of the solution taken out on iron wire solidifies on cooling. Pour on porcelain and cool. (Ph. L. 1836.) Iodine, 6 oz.; iron filings, 2 oz.; water, 4-1/2 pints; mix, boil in a sand bath until the liquid turns to a pale green, filter, wash the residuum with a little water, evaporate the mixed liquors in an iron vessel at 212° Fahr. to dryness, and immediately put the iodide into well-stoppered bottles.

Iodine, 1 oz., and clean iron filings or turnings, 1/2 oz., are put into a Florence flask with distilled water, 4 fl. oz., and having applied a gentle heat for 10 minutes, the liquid is boiled until it loses its red colour; it is then at once filtered into a second flask, the filter washed with water, 1 fl. oz., and the mixed liquid is boiled down, until it solidifies on cooling.

With sugar: SACCHARINE IODIDE OF IRON, SACCHARUM FERRI IODIDI, FERRI IODIDUM SACCHARATUM, L. Iron (in powder), 1 dr.; water, 5 dr.; iodine, 4 dr.; obtain a solution of iodide of iron, as above, and add to it of sugar of milk (in powder), 1-1/4 oz.; evaporate at a temperature not exceeding 122° Fahr., until the mass has a tenacious consistence, then further add of sugar of milk, 1 oz., reduce the mixture to powder, and preserve it in a well-stoppered bottle. Every 6 gr. contains 1 gr. of iodide of iron.

From “syrup of iodide of iron” exposed in a shallow vessel, in a warm place, until it crystallises; the crystals are collected, dried, and powdered. A simpler plan is to gently evaporate the whole to dryness, and to powder the residuum. The saccharine iodide may be kept for some time in a corked bottle without undergoing decomposition.

_Obs._ The preparation of the above compound, like that of the citrates, has formed a fertile subject during some years for pharmaceutical amateurs to dilate upon. There is in reality not the least difficulty in the process. As soon as iodine and iron are mixed together under water much heat is evolved, and if too much water be not used the combination is soon complete, and the liquor merely requires to be evaporated to dryness, out of contact with the air, at a heat not exceeding 212° Fahr. This is most cheaply and easily performed by employing a glass flask, with a thin broad bottom and a narrow mouth, by which means the evolved steam excludes air from the vessel. The whole of the uncombined water may be known to be evaporated when vapour ceases to condense on a piece of cold glass held over the mouth of the flask. A piece of moistened starch paper occasionally applied in the same way will indicate whether free iodine is evolved; should such be the case, the heat should be immediately lessened. When the evaporation is completed, the mouth of the flask should be stopped up by laying a piece of sheet india rubber on it, and over that a flat weight; the flask must be then removed, and when cold broken to pieces, the iodide weighed, and put into dry and warm stoppered wide-mouth glass phials, which must be immediately closed, tied over with bladder, and the stoppers dipped into melted wax.

_Prop., &c._ Ferrous iodide evolves violet vapours by heat, and ferric oxide remains. When freshly made it is totally soluble in water, and from this solution, when kept in a badly stoppered vessel, ferric hydrate is very soon precipitated; but with iron wire immersed in it, it may be kept clear in a well-stoppered bottle.——_Dose_, 1 to 3 gr., or more, as a tonic, stimulant, and resolvent. It has been given with advantage in anæmia, chlorosis, debility, scrofula, and various glandular affections.

=Ferrous Lactate.= Fe(C_{3}H_{5}O_{3})_{2}. _Syn._ PROTOLACTATE OF IRON; FERRI LACTAS, FERRUM LACTICUM, L. _Prep._ Boil iron filings in lactic acid diluted with water, until gas ceases to be evolved, and filter whilst hot into a suitable vessel, which must be at once closely stopped; as the solution cools, crystals will be deposited, which after being washed, first with a little cold water, and then with alcohol, are to be carefully dried. The mother liquor, on being digested, as before, with fresh iron, will yield more crystals.

Into sour whey, 2 lbs., sprinkle sugar of milk and iron filings, of each, in fine powder, 1 oz.; digest at about 100° Fahr., until the sugar of milk is dissolved, then add a second portion, and as soon as a white crystalline powder begins to form, boil the whole gently, and filter into a clean vessel; lastly, collect, wash, and dry the crystals as before.

_Prop., &c._ Ferrous lactate is a greenish-white salt; and when pure, forms small acicular or prismatic crystals, which have a sweetish ferruginous taste, and are soluble in about 48 parts of cold and in 12 parts of boiling water. It has been regarded by many high authorities as superior to every other preparation of iron for internal use, as being at once miscible with the lactic acid of the gastric juice, instead of having to be converted into a lactate at the expense of that fluid, as it is asserted is the case with the other preparations of iron.——_Dose_, 2 to 6 gr., frequently, in any form most convenient.

=Ferrous Ma′late (Impure).= _Syn._ FERRI MALAS IMPURUS, L. _Prep._ (P. Cod., 1839.) Porphyrised iron filings, 1 part; juice of sour apples, 8 parts; digest for 3 days in an iron vessel, evaporate to one half, strain through linen whilst hot, further evaporate to the consistence of an extract, and preserve it from the air.——_Dose_, 5 to 20 gr., where the use of iron is indicated.

=Ferrous Nitrate.= (FeNO_{3})_{2}. _Syn._ PROTONITRATE OF IRON, NITRATE OF PROTOXIDE OF IRON; FERRI NITRAS, L. By dissolving ferrous sulphide in dilute sulphuric acid, in the cold, and evaporating the solution _in vacuo_. Small green crystals, very soluble, and prone to oxidation.

=Ferrous Oxalate.= (U. S.) _Syn._ FERRI OXALAS. _Prep._ Sulphate of iron, 2 oz.; oxalic acid, 396 gr.; distilled water, q. s. Dissolve the sulphate in 30 oz. (old measure), and the acid in 15 oz. (old measure) of distilled water. Filter the solutions, mix them, shake together, and set aside until the precipitate is formed. Decant the clear liquid, wash the precipitate thoroughly, and dry it with a gentle heat.

=Ferrous Oxide.= FeO. _Syn._ PROTOXIDE OF IRON, FERRI PROTOXYDUM, L. This substance is almost unknown in a pure state, from its extreme proneness to absorb oxygen and pass into the sesquioxide.

=Ferrous Phosphate.= _Syn._ PHOSPHATE OF IRON, NEUTRAL P. OF PROTOXIDE OF IRON, BIMETALLIC FERROUS ORTHOPHOSPHATE (Odling); FERRI PHOSPHAS (Ph. U. S.), L. A salt formed from ordinary or tribasic phosphoric acid.

_Prep._ (B. P.) Ferrous sulphate, 3; sodium phosphate, 2-1/2; sodium acetate, 1; boiling distilled water, 80; dissolve the sulphate and sodium salts, each in half the water, mix, and stir carefully, filter through calico, wash with hot distilled water until it ceases to give a precipitate with barium chloride, dry at a heat not exceeding 120° Fahr. (Ph. U. S.) Ferrous sulphate, 5 oz.; sodium phosphate, 6 oz.; dissolve each separate in 2 quarts of water, mix the solutions, and after repose for a short time wash and dry the precipitate.

_Prop., &c._ A slate-coloured powder; insoluble in water; soluble in dilute nitric and hydrochloric acid.——_Dose_, 5 to 10 gr.; in amenorrhœa, diabetes, dyspepsia, scrofula, &c.; and _externally_, as an application to cancerous ulcers.

=Ferrous Sulphate.= FeSO_{4}.7Aq. _Syn._ PROTOSULPHATE OF IRON, SULPHATE OF IRON, COPPERAS, GREEN VITRIOL, SHOEMAKER’S BLACK; FERRI SULPHAS (B. P., Ph. L. E. & D.), VITRIOLUM FERRI. The crude sulphate of iron or green vitriol of commerce (FERRI SULPHAS VENALIS, Ph. L.) is prepared by exposing heaps of moistened iron pyrites or native bisulphuret of iron to the air for several months, either in its unprepared state or after it has been roasted. When decomposition is sufficiently advanced, the newly formed salt is dissolved out with water, and the solution crystallised by evaporation. In this state it is very impure. The ferrous sulphate or sulphate of iron employed in medicine is prepared as follows:——

_Prep._ (B. P.) Iron wire, 4; sulphuric acid, 4; distilled water, 30. Pour the water on the iron, add the acid, and when the disengagement of gas has nearly ceased, boil for ten minutes. Filter through paper. Allow to stand twenty-four hours, and collect the crystals. Sulphuric acid, 1 fl. oz.; water, 4 pints; mix, and add of commercial sulphate of iron, 4 lbs.; iron wire, 1 oz.; digest with heat and occasional agitation until the sulphate is dissolved, strain whilst hot, and set aside the liquor that crystals may form; evaporate the mother-liquor for more crystals, and dry the whole.

Dissolve the transparent green crystals of the impure sulphate of iron in their own weight of water, acidulated with sulphuric acid, and re-crystallise.

The formula of the Ph. U. S. is similar.

Dried; FERRI SULPHAS EXSICCATA, B. P.; FERRI SULPHAS EXSICCATUM——Ph. E., F. S. SICCATUM——Ph. D. From ferrous sulphate, heated in a shallow porcelain or earthen vessel, not glazed with lead, till it becomes a greenish-grey mass, and then reduced to powder. The heat should be that of an oven, or not exceeding 400° Fahr. Five parts of the crystallised sulphate lose very nearly 2 parts by drying.

Granulated; FERRI SULPHAS GRANULATA, L. (B. P.) A solution of iron wire, 4 oz., in sulphuric acid, 4 fl. oz., diluted with water, 1-1/2 pint, after being boiled for a few minutes, is filtered into a vessel containing rectified spirit, 8 fl. oz., and the whole stirred until cold, when the granular crystals are collected on a filter, washed with rectified spirit, 2 fl. oz., and dried, first by pressure between bibulous paper, and next beneath a bell-glass over sulphuric acid, after which they are put into a stoppered bottle, to preserve them from the air.

_Prop., &c._ Ferrous sulphate forms pale bluish-green rhombic prisms, having an acid, styptic taste, and acid reaction; it dissolves in two parts of cold and less than one part of boiling water; at a dull-red heat it suffers decomposition; sp. gr. 1·82. It is perfectly soluble in water; a piece of iron put into the solution should not be covered with metallic copper. By exposure to the air it effloresces slightly, and is partly converted into a basic ferric sulphate.——_Dose_, 1/2 to 4 gr., in pills or solution; externally, as an astringent or styptic. In the arts, as sulphate of iron (copperas), it is extensively used in dyeing, and for various other purposes. The dried sulphate (ferri sulphus exsiccatum) is chiefly used to make pills.

Crude sulphate of iron is frequently contaminated with the sulphates of copper, zinc, manganese, aluminium, magnesium, and calcium, which, with the exception of the first, are removed with difficulty. It also contains variable proportions of the neutral and basic ferric sulphates. The preparation obtained by direct solution of iron in dilute sulphuric acid should, therefore, be alone used in medicine.

In commerce there are four varieties of crude sulphate of iron or copperas known,——greenish-blue, obtained from acid liquors,——pale green, from neutral liquors,——emerald green, from liquors containing ferric sulphate,——and ochrey brown, which arises from age and exposure of the other varieties to the air. Even the first two of these contain traces of ferric sulphate, and hence give a bluish precipitate with ferrocyanide of potassium; whereas the pure sulphate gives one which is at first nearly white.

=Ferrous Sulphide.= FeS. _Syn._ SULPHURET OF IRON, SULPHIDE OF I., PROTOSULPHIDE OF I.; FERRI SULPHURETUM (Ph. E. & D.), L. _Prep._ (Ph. E. & D.) Expose a bar of iron to a full white heat, and instantly apply a solid mass of sulphur to it, observing to let the melted product fall into water; afterwards separate the sulphide from the sulphur, dry, and preserve it in a closed vessel.

From sublimed sulphur, 4 parts; iron filings, 7 parts; mixed together and heated in a common fire till the mixture begins to glow, and then removing the crucible from the heat, and covering it up, until the reaction is at an end, and the whole has become cold.

Hydrated; FERRI PROTOSULPHURETUM HYDRATUM, L. By adding a solution of ammonium sulphide or of potassium sulphide to a neutral solution of ferrous sulphate made with recently distilled or boiled water; the precipitate is collected on a filter, washed as quickly as possible with recently boiled water, squeezed in a linen cloth, and preserved in the pasty state, under water, as directed under ferric hydrate.

_Prop., &c._ The sulphide prepared in the dry way is a blackish brittle substance, attracted by the magnet. It is largely used in the laboratory as a source of sulphuretted hydrogen. The hydrated sulphide is a black, insoluble substance, rapidly decomposed by exposure to the air. Proposed by Mialhe as an antidote to the salts of arsenic, antimony, bismuth, lead, mercury, silver, and tin, and to arsenious acid; more especially to white arsenic and corrosive sublimate. A gargle containing a little hydrated sulphide of iron will instantly remove the metallic taste caused by putting a little corrosive sublimate into the mouth. (Mialhe.) On contact with the latter substance it is instantly converted into ferrous chloride and mercurous sulphide, two comparatively inert substances. It is administered in the same way as ferrous hydrate. When taken immediately after the ingestion of corrosive sublimate, it instantly renders it innocuous; but when the administration is delayed until 15 or 20 minutes after the poison has been swallowed, it is almost useless.

=Ferrous Tar′trate.= _Syn._ FERRI TARTRAS, FERRI PROTOTARTRAS, L. _Prep._ 1. From iron filings, 2 parts; tartaric acid, 1 part; hot water, q. s.; digest together until reaction ceases, agitate the liquid, pour off the turbid solution, and collect, wash, and dry the powder as quickly as possible, and keep it out of contact with the air.

2. Crystallised potassium tartrate, 132 parts; ferrous sulphate, 139 parts; dissolve each separately, mix the solutions, and collect the precipitate as before. A nearly insoluble powder; seldom used.

_Obs._ By dissolving the corresponding hydrates in a solution of tartaric acid, employing the former in slight excess, and evaporating, both the ferrous and ferric tartrate are easily obtained.

=IRON AL′UM.= See ALUMS.

=IRON CEMENT′.= See CEMENTS.

=IRON, DIALYSED.= (Paris Pharmaceutical Society.) _Syn._ FERRUM DIALYSATUM. OXIDE DE FER DIALYSÉ. _Prep._ Solution of ferric chloride (sp. gr. 1·245), 100 grams; solution of ammonia (sp. gr. 1·169), 35 grams; add the ammonia in small quantities to the ferric chloride; at first the precipitate formed is redissolved very rapidly, but afterwards disappears more slowly. When the liquor has again become transparent, it is introduced into the dialyser; the distilled water in which the vessel containing the ferruginous solution is placed, must be frequently renewed. After a time the highly coloured solution is no longer precipitated by silver nitrate, and gives no acid reaction. It is then absolutely free from the disagreeable taste of certain ferruginous preparations. A small quantity of hydrochloric acid always remains in the liquor, which may be shown by precipitating the oxide of iron by a slight excess of ammonia, filtering, adding an excess of nitric acid, and then silver nitrate. Ten c.c. are evaporated, and from the residue must be calculated how much distilled water is required to be added to produce a 10 per cent. solution.

2. (‘American Journal of Pharmacy.’) Take 10 parts of liq. ferri perchlor. (B. P.), precipitate by _liquor ammoniæ_, and wash the precipitate thoroughly. Mix this with 12 parts of liq. ferri perchlor. (B. P.), and place in a dialyser. The dialyser is placed in a suitable vessel with distilled water, the water under it renewed every 24 hours. The operation is continued until no trace of chlorine exists, at which time the preparation is found to be neutral. It usually takes from twelve to fifteen days to complete the process.

The resulting preparation, which should be of a deep dark red colour, contains about 5 per cent. of the oxide of iron. If the solution after completion of the operation should contain more than 5 per cent. of iron, it may be diluted with dialysed water till it reaches that point.

The above formula is said to furnish an article precisely similar to the original Bravais’ dialysed iron.

3. (E. B. Shuttleworth.) Add ammonia to a solution of perchloride of iron as long as the precipitate formed is redissolved. A solution is produced which contains ferric hydrate dissolved in ferric chloride, with free chloride of ammonium. Either the liquor ferri perchlor. fort. (B. P.), or the liquor ferri chloridi (U. S.), may be conveniently used, and the liquor ammoniæ, sp. gr. ·959 or ·960, of either Pharmacopœia will be found a convenient strength. If the ammonia be added to the strong solution of iron, considerable heat is evolved, and, on cooling, the preparation becomes gelatinised——often so much so that the vessel containing it may be inverted. It is better to avoid this result, and to such end the solution of perchloride must be diluted until of a sp. gr. of about 1·300. This degree may be nearly enough approached by diluting two measures of the B. P. liquor with one of water; or adding one measure of water to five of the U. S. preparation. This solution will generally remain permanently bright and fluid. The amount of liquor ammoniæ required will of course vary with the acidity of the perchloride. The liquor ferri B. P. will sometimes bear as much as an equal volume. A gelatinised solution, even when made from the undiluted liquor, will often become fluid when put upon the dialyser, but, as I have said before, it is better to work with bright solutions.

4. (Dr Pile.) Dr Pile, noticing the fact that chloride of sodium is one of the most rapid crystalloids to dialyse, used a solution of carbonate of sodium to add to the solution of ferric chloride in place of the ammonia so generally recommended, and with great success. The solution of ferric chloride (U. S.) which has been neutralised by a cold solution of carbonate of sodium is poured into a floating dialyser. Starting with 1 pint of solution of ferric chloride, which on being treated with the sodium solution and ready to dialyse, had a sp. gr. of 1·175, it had in 5 days increased to 5 pints. The water in which the dialyser floated was changed daily. At the end of five days it had passed through the membrane all the crystalloids, was free from taste of foreign substances, and owing to increase of bulk had now the sp. gr. of 1·0295, and on evaporation yielded 5 per cent. dry oxide of iron. Too long dialysation will cause the solution of iron to become gelatinous.

Mr Shuttleworth[3] says that an efficient dialyser may be made out of one of the flat hoops of an ordinary flour barrel, a bell jar, or even an inverted glass funnel. He gives the preference to the former, and limits its diameter to ten or twelve inches; if it exceeds this, the septum is liable to bulge in the centre, and to make the layer of liquid too deep at that point.

[Footnote 3: ‘Canadian Pharmaceutical Journal,’ Oct., 1877.]

The parchment paper employed for the septum must be entirely free from holes; this is an essential condition, and if any should be discovered——by the simple process of sponging the upper surface of the paper with water, and then carefully examining the under surface,——they must be stopped by means of a little white of egg, applied and coagulated by heat, or by a drop of collodion.

The parchment paper is not the kind ordinarily known under that name, but a less porous description, which has been made by previous immersion in dilute sulphuric acid.

Well-washed bladder, deprived of its outer coat, also makes a good septum.

The septum should be tied around the hoop with twine, but not too tightly, and should be so arranged that its edges shall be left standing up around the hoop, so as to absorb any liquid escaping from the hoop at its junction with the septum. The dialyser being ready for use, the liquid intended for dialysis is poured into it to a depth of not more than half an inch, and the dialyser with its contents is then floated on the surface of some distilled water, contained in a suitable receptacle.

The hoop must only be allowed to sink just below the level of the water; if it gets below this point, it will be necessary to keep it up by some support or the other.

It is necessary to change the water in the outer vessel daily. For the first two or three days distilled water should always be used. When this is not obtainable rain water should be employed. When the water shows the absence of chlorides, and the preparation ceases to have a ferruginous taste, the operation may be regarded as finished. The process generally occupies one or two weeks.

“A pig’s bladder, completely filled with the iron solution, securely tied, and immersed in water frequently changed, answers well for making this preparation. The process requires a longer time than with a carefully regulated and properly conducted dialysis, but it entails considerably less trouble. I consider it an advantage to procure the bladder perfectly fresh, as it is then easily cleaned by pure water, and alkaline ley need not be used. Great care is necessary in tying the neck carefully. This can be best accomplished by a few turns of iron wire. Above this may be secured a piece of twine, to suspend the bladder, by means of a stick, or rod, placed on the edge of the vessel containing the water. The bladder should be perfectly full, and immersed altogether in water. The attraction of the solution for the water is so great, that considerable pressure is manifested, and should any parts or holes be in the bladder, the liquid will be forced out, water will take its place, and failure result.”[4]

[Footnote 4: ‘Canadian Pharmaceutical Journal,’ Oct., 1877.]

Pretty general consent appears to have fixed the strength of the solution of dialysed iron at five per cent. Where it exceeds this, the solution must be diluted with distilled water; and where it falls short of the amount, it will have to be reduced to the required volume by standing it in a warm and dry situation. The employment of much heat must be particularly avoided as it very frequently leads to the destruction of the compound; hence every care should be taken to render the evaporation of the fluid unnecessary.

There seems little doubt that the so-called “dialysed iron” is an oxychloride of the metal. Prof. Maisch[5] believes it to be a very basic oxychloride of iron. On the supposition that the oxychloride and chloride of iron are both present in the liquid put into the dialyser, the origin of the oxychloride admits of easy explanation:——The chloride being a crystalloid, diffuses through the septum into the outer water, and thus becomes separated from the oxychloride, which being a colloid, and incapable of a passage through the membrane, remains in solution in the dialyser.

[Footnote 5: Ibid., Oct., 1877.]

The comparative freedom from taste and easy assimilation of the oxychloride of iron render it a valuable therapeutic agent. The dose of the five per cent. solution is 15 to 50 drops daily, in divided doses. Syrup forms a pleasant vehicle for its administration.

Dialysed iron has been successfully employed in a case of arsenical poisoning. The ‘American Journal of Pharmacy’ for January, 1878, contains an interesting paper by Dr Mattison detailing a series of experiments, which conclusively prove its value as an antidote to arsenic. Dr Mattison recommends the administration of the iron to be immediately followed by a teaspoonful or more of common salt.

=IRON FI′′LINGS.= _Syn._ FERRI RAMENTA (Ph. L. 1836). FERRI LIMATURA (Ph. E.), FERRI SCOBS (Ph. D.). The usual method of preparing iron filings for medical purposes has been already noticed; the only way, however, to obtain them pure, is to act on a piece of soft iron with a clean file. The Fr. Cod. orders them to be forcibly beaten in an iron mortar, and to be separated from oxide and dust by means of a fine sieve, and from the grosser parts by means of a coarse hair-sieve.——_Dose_, 10 to 30 gr., in sugar or honey, as a chalybeate; in larger doses it is an excellent vermifuge, especially for ascarides or the small thread-worm.

=IRON LIQ′UOR.= _Syn._ PYROLIGNITE OF IRON, DYER’S ACETATE OF I., BLACK LIQUOR, TAR IRON L.; FERRI ACETAS VENALIS, L. This article, so extensively used in dyeing, is a crude mixed acetate of the protoxide and sesquioxide of iron. It is usually prepared by one or other of the following methods:——

1. Old scraps of iron (hoops, worn-out tin-plate, &c.) are left in a cask of pyroligneous acid, occasional agitation being had recourse to, until a sufficiently strong solution is obtained. By keeping the acid moderately warm in suitable vessels it will become saturated with the iron in a few days. With cold acid, on a large scale, forty days or more are required to complete the process.

2. A solution of pyrolignite or crude acetate of lime, is added to another of green copperas, as long as a precipitate is formed; after repose, the clear liquor is decanted.

=IRON, REDUCED.= _Syn._ QUEVENNE IRON; FERRUM REDACTUM (B. P.), FERRI PULVIS, L.; FER REDUIT, F. _Prep._ This preparation, which consists of metallic iron in a fine state of division mixed with a variable amount of magnetic oxide of iron, is made by passing perfectly dry hydrogen over peroxide of iron heated to redness in a gun-barrel.

_Prop._ A greyish-black powder, attracted by the magnet, and exhibiting metallic streaks when rubbed with firm pressure in a mortar. Rapidly absorbs oxygen, and must, therefore, be preserved from the air in well-stoppered bottles. It dissolves in hydrochloric acid with the evolution of hydrogen. 10 grains added to an aqueous solution of 50 grains of iodine and 50 grains of iodide of potassium, and digested with them in a small flask at a gentle heat, should leave not more than 5 grains undissolved, which should be entirely soluble in hydrochloric acid.

_Uses._ In _medicine_ it is chiefly given to restore the condition of the blood in all anæmic states of the system. There is no pulverulent state of iron so convenient as this for children, as it has no taste, and only a very small dose is required.——_Dose_, 1 to 5 grains (children, 1/4 to 1 grain), in powder, pill, or between bread and butter.

=Iron reduced by Electricity.= See ELECTRICITY, Iron reduced by.

=Iron, to remove Rust from Polished.= Rust of iron may be removed from a polished grate by means of emery paper, or by scraping some Bath-brick to a fine powder, mixing it with a little oil and rubbing the spots well with a piece of flannel dipped in this mixture; after which some whiting should be applied by diligent friction. This operation requires daily repetition until the rust has disappeared. Steel fire-irons, fenders, &c., when put aside in the summer, should be previously smeared thinly over with a species of paraffin, known to druggists by the name of ‘vaseline’ or ‘cosmoline,’ or with grease, mercurial ointment, &c.

=Iron, to remove the Stains of, from Marble.= Rub on very cautiously (confining it to the surface only occupied by the spot) some strong hydrochloric acid, removing it directly the spot disappears. Should this cause any diminution in the polish, this may be restored by means of emery paper.

=IRON WIRE.= _Syn._ FERRUM IN FILA TRACTUM (Ph. L.), FERRI FILUM (Ph. E.), FERRI FILA (Ph. D.), L. This is the only form of metallic iron retained in the Ph. L. It is used to make preparations of iron.

=ISATINE.= C_{16}H_{10}N_{2}O_{4}. A yellow crystalline body obtained by the oxidation of indigo. When acted upon by potash it becomes converted into aniline. Isatine may be formed by heating indigo in a dilute solution of dichromate of potash and sulphuric acid, or by treating indigo under proper conditions with nitric acid.

=ISCHU′RIA.= In _pathology_, retention, stoppage, or suppression of the urine.

=I′′SINGLASS.= _Syn._ ICHTHYOCOLLA, L. The finest kinds of isinglass are obtained from various species of the genus _Acipenser_, or sturgeon, that from the great sturgeon being perhaps the most esteemed. It is the air-bag, swimming bladder, or sound, dried without any other preparation than opening, folding, or twisting it. The picked or cut isinglass of the shops consists of the lamps of staple isinglass picked in shreds by women and children, or cut by machines.

_Prop., &c._ Good isinglass is the purest natural gelatin known. Its quality is determined by its whiteness, absence of the least fishy odour, and ready and almost entire solubility in boiling water; the solution forming a nearly white, scentless, semi-transparent, solid jelly, when cold. It is soluble in weak acids, and this solution is precipitated by alkalies. The aqueous solution is not precipitated by spirit of the common strengths. 1 part of good isinglass dissolved in 25 parts of hot water forms a rich, tremulous jelly. It is very commonly adulterated. Of the different varieties of isinglass, the Russian is the best and most soluble. See GELATIN.

=ISOM′ERISM.= In _chemistry_, identity of composition, with dissimilarity of properties. Isomeric compounds (isomerides) are such as contain the same elements in the same proportions, but which differ from each other in their chemical properties; thus, formate of ethyl and acetate of methyl are isomeric, having precisely the same ultimate composition, though differing in the arrangement of their elements.

=ISOMOR′PHISM.= In _chemistry_, the quality possessed by bodies differently composed of assuming the same crystalline form. Isomorphous substances are found to be closely allied in their chemical nature; and the fact of two bodies crystallising in the same form has often led to the discovery of other points of similarity between them. The alums, for instance, no matter what their components, all crystallise in octahedra, and a crystal of potassium-alum, if transferred to a solution of chrome-alum, will continue to increase with perfect regularity from the deposition of the latter salt.

=IS′SUE.= _Syn._ FONICULUS, L. In _surgery_, a small artificial ulcer formed on any part of the body by means of caustic or the lancet, and kept open by daily introducing an ISSUE PEA covered with some digestive or stimulating ointment; the whole being duly secured by an appropriate bandage.

=ISSUE PEAS.= _Syn._ PISÆ PRO FONTICULIS, L. Those of the shops are the immature fruit of the orange tree (ORANGE BERRIES). They are usually smoothed in a lathe. Issue peas are also ‘turned’ from orris root. The following compound issue peas are occasionally employed:——

1. Orris root (in powder) and Venice turpentine, of each 1 part; turmeric, 2 parts; beeswax, 3 parts; melted together and made into peas whilst warm.

2. Beeswax, 3 parts; melt, add of Venice turpentine, 1 part; mix, and further add, of turmeric, 2 parts; orris root (in powder), 1 part; mix well, and form the mass into peas whilst warm. More irritating than the common pea.

3. (Dr Gray.) Beeswax, 12 parts; verdigris and white hellebore, of each 4 parts; orris root, 3 parts; cantharides, 2 parts; Venice turpentine, q. s. Used to open issues instead of caustic, but their employment requires care.

=ISSUE PLAS′TERS.= See PLASTERS.

=ITCH.= _Syn._ YOUK‡, SCOTCH FIDDLE‡; PSORA, SCABIES, L.; GALE, Fr. In _pathology_, a cutaneous disease, caused by a minute insect lodging under the skin, and readily communicated by contact. There are four varieties of itch, distinguished by nosologists by the names——_scabies papuliformis_, or rank itch;——_scabies lymphatica_, or watery itch; _scabies purulenta_, or pocky itch; _scabies cachectica_, a species exhibiting appearances resembling each of the previous varieties. Our space will not permit more than a general notice of the common symptoms, and the mode of cure which is equally applicable to each species, and will not prove injurious to other skin diseases simulating the itch.

The common itch consists of an eruption of minute vesicles, principally between the fingers, bend of the wrist, &c., accompanied by intense itching of the parts, which is only aggravated by scratching. The usual treatment is repeated applications of sulphur ointment (simple or compound), well rubbed in once or twice a day, until a cure is effected; accompanying its use by the internal exhibition of a spoonful or more of flowers of sulphur, mixed with treacle or milk night and morning. Where the use of sulphur ointment is objectionable, a sulphur bath, or a lotion or bath of sulphurated potash, or of chloride of lime, may be employed instead.

In the ‘Canadian Pharmaceutical Journal’ for 1872 is a paper by Professor Rothmund recommending the employment of balsam of Peru in this objectionable disease. The writer states that one application generally effects a cure, and that its use does away with the necessity of baths. He recommends the balsam being rubbed all over the naked body. Carbolic acid is another and much cheaper remedy proposed by the same author. To obviate its caustic action he advises the acid to be mixed with glycerin or linseed oil, in the proportion of one scruple of the acid to two ounces of either excipient. He considers the objection to this remedy may be that it enters too rapidly into the circulation. Another agent employed by Professor Rothmund is a lotion composed of one part of carbolate of sodium dissolved in 12 parts of water. The affected parts of the skin are to be rubbed with this three times a day.

It is further recommended to continue this treatment 8 or 10 days after the cure, in order to kill any acari or their eggs that may have lurked among the clothes or bed-linen. See BATH, LOTION (Itch), OINTMENT, PSORIASIS, &c.

=I′VORY.= The osseous portion of the tusks and teeth of the male elephant, the hippopotamus, wild boar, &c. That of the narwhal or seahorse is the most esteemed, on account of its superior hardness, toughness, translucency, and whiteness. The dust or shavings (IVORY DUST, IVORY SHAVINGS) of the turner form a beautiful size or jelly when boiled in water. VEGETABLE IVORY is the hard albumen of the seed of the _Phytelephas macrocarpa_, one of the Palm family.

Ivory may be dyed or stained by any of the ordinary methods employed for woollen, after being freed from dirt and grease; but more quickly as follows:——

1. BLACK. The ivory, well washed in an alkaline lye, is steeped in a weak neutral solution of nitrate of silver, and then exposed to the light, or dried and dipped into a weak solution of sulphide of ammonium.

2. BLUE. Steep it in a weak solution of sulphate of indigo which has been nearly neutralised with salt of tartar, or in a solution of soluble Prussian blue. A still better plan is to steep it in the dyer’s green indigo-vat.

3. BROWN. As for black, but using a weaker solution of silver.

4. GREEN. Dissolve verdigris in vinegar, and steep the pieces therein for a short time, observing to use a glass or stoneware vessel; or, in a solution of verdigris, 2 parts; and sal ammoniac, 1 part, in soft water.

5. PURPLE. Steep it in a weak neutral solution of terchloride of gold, and then expose it to the light.

6. RED. Make an infusion of cochineal in liquor of ammonia, then immerse the pieces therein, having previously soaked them for a few minutes in water very slightly acidulated with aquafortis.

7. YELLOW. _a._ Steep the pieces for some hours in a solution of sugar of lead, then take them out, and when dry, immerse them in a solution of chromate of potassa.

_b._ Dissolve as much of the best orpiment in solution of ammonia as it will take up, then steep the pieces therein for some hours; lastly, take them out and dry them in a warm place, when they will turn yellow.

Ivory is etched or engraved by covering it with an etching ground or wax, and employing oil of vitriol as the etching fluid.

Ivory is rendered flexible by immersion in a solution of pure phosphoric acid (sp. gr. 1·13), until it loses, or partially loses, its opacity, when it is washed in clean cold soft water, and dried. In this state it is as flexible as leather, but gradually hardens by exposure to dry air. Immersion in hot water, however, restores its softness and pliancy. According to Dr Ure, the necks of some descriptions of INFANTS’ FEEDING BOTTLES are thus made.

Ivory is whitened or bleached by rubbing it with finely powdered pumice-stone and water, and exposing it to the sun whilst still moist, under a glass shade, to prevent desiccation and the occurrence of fissures; observing to repeat the process until a proper effect is produced. Ivory may also be bleached by immersion for a short time in water holding a little sulphurous acid, chloride of lime, or chlorine, in solution; or by exposure in the moist state to the fumes of burning sulphur, largely diluted with air. Cloez recommends the ivory or bones to be immersed in turpentine and exposed for three or four days to sunlight. The object to be bleached should be kept an eighth or a fourth of an inch above the bottom of the bath by means of zinc supports. For the preparation of ivory intended for miniature painting Mr Ernest Spon in his useful work, ‘Workshop Receipts,’ says: “The bleaching of ivory may be more expeditiously performed by placing the ivory before a good fire, which will dispel the wavy lines if they are not very strongly marked, that frequently destroy the uniformity of surface.”

Ivory may be gilded by immersing it in a fresh solution of proto-sulphate of iron, and afterwards in solution of chloride of gold.

Ivory is wrought, turned, and fashioned in a similar manner and with similar tools to those used for bone and soft brass.

_Obs._ Bone for ornamental purposes is treated in a similar way to ivory, but less carefully, owing to its inferior value. The bones of living animals may be dyed by mixing madder with their food. The bones of young pigeons may thus be tinged of a rose colour in 24 hours, and of a deep scarlet in 3 or 4 days; but the bones of adult animals take fully a fortnight to acquire a rose colour. The bones nearest the heart become tinged the soonest. In the same way logwood and extract of logwood will tinge the bones of young pigeons purple. (Gibson.)

=1.= =Ivory, Artificial.= Let a paste be made of isinglass, egg-shell in very fine powder, and brandy. Give it the desired colour, and pour it while warm into oiled moulds. Leave the paste in the moulds until it becomes hard.

=2.= (L’Union Pharmaceutique.) Two parts of caoutchouc are dissolved in 36 parts of chloroform, and the solution is saturated with pure gaseous ammonia. The chloroform is then distilled off at a temperature of 85° C. The residue is mixed with phosphate of lime or carbonate of zinc, pressed into moulds and dried. When phosphate of lime is used the product possesses to a considerable degree the nature and composition of ivory.

=IVORY BLACK.= See BLACK PIGMENTS.

=JABORANDI.= _Syn._ IABORANDI, JAMBORANDI. The above names are given by the natives of Brazil, Paraguay, and other parts of South America to any indigenous plants possessing strongly stimulant, diaphoretic, and sialagogue properties, which are principally employed in those countries as antidotes for the bites and stings of venomous snakes and insects.

As far as they have been examined, all the plants known under the generic name ‘jaborandi’ have been traced to the two natural orders, _Rutaceæ_ and _Piperaceæ_. Those exercising the most marked physiological effects appear to belong to the former or the rutaceous division, and are very probably different species of _Pilocarpus_. The drug was first introduced into Europe by Dr Coutinho, of Pernambuco, who some four years since sent a sample of it to Dr Gubler, of Paris, by whom it was administered to some of the patients of the Beaujon Hospital there. The jaborandi with which these experiments were made was identified by Professor Baillon, of Paris, as belonging to the _Pilocarpus pinnatus_ (_pinnatifolius_). Four to six grams of the bruised leaves and twigs were infused in a cup of water, and the patient being put to bed, in ten minutes after taking the draught, finds himself bathed in a perspiration lasting for four or five hours, this being so profuse as to render several changes of linen necessary during the time. Accompanying the diaphoresis are great salivary and bronchial secretions, which sometimes will not permit the patient to speak without his mouth becoming filled with water.

The quantity of saliva is stated to have sometimes equalled a litre in measure. These experiments have been repeated in this country with analogous effects; in one case reported with jaborandi obtained from the Beaujon Hospital, and in another from London; results the similarity of which strongly point to a corresponding composition in the two specimens of the plant used, if, as seems not improbable, they may have belonged to different species. A case of impaired vision following the administration of jaborandi is also recorded; but this seems evidently to have been the effect of an overdose of the drug.[6]

[Footnote 6: ‘Pharm. Journal,’ 3rd series, V, 364 and 561.]

When jaborandi is administered in divided doses instead of producing salivation or sweating, it acts as an active diuretic only, increasing the flow of urine to nearly double the usual amount. M. Albert Robins says:——“The effect of jaborandi on animals is very marked; guinea-pigs are seized with salivation, weeping and diarrhœa, true ecchymoses being found in the intestines, and dogs become instantly salivated, their gastric secretion being also much increased.”[7]

[Footnote 7: ‘Medical Times and Gazette.’]

Drs Coutinho and Gubler affirm they have employed jaborandi in dropsy, bronchitis, diabetes, and various other diseases, and that they have found it fully answer their expectations; and in one case of albuminuria it is narrated that a permanent diminution of albumen from 14·40 to 12 grammes followed its use.

An alkaloid has been obtained from the piperaceous jaborandi by Parodi, and named by him _jaborandine_. Some short time afterwards Mr A. W. Gerrard succeeded in separating the alkaloid from the rutaceous jaborandi, to which, in accordance with Mr Holmes’ suggestion, and because Parodi had anticipated him in the adoption of the previous title, he gave the name _pilocarpine_.

Mr Gerrard recommends the following process for the preparation of _pilocarpine_:——“Prepare a soft extract either with leaf or bark, with 50 per cent. alcohol. Digest this with water, filter and wash. Evaporate the filtrate to a short extract, cautiously add ammonia in slight excess, shake well with chloroform, separate the chloroform solution, and allow it to evaporate; the residue is the alkaloidal pilocarpine with probably a small amount of impurity.” Mr Gerrard has also succeeded in preparing a crystalline nitrate and hydrochlorate of the alkaloid, both of which possess the medicinal powers of the jaborandi.

The abridged description of a sample of jaborandi from Pernambuco is from Mr Holmes’ paper in the ‘Pharmaceutical Journal.’[8] The cut is from the last edition of Royle’s ‘Materia Medica.’ “The specimens of the plant examined appear to belong to a shrub about 5 feet high. The root is cylindrical, hardly tapering at all, nearly 3/4 inch in diameter for the first 12 inches, and very sparingly branched. Bark of root of a pale yellowish brown, about a line in thickness, and has a short fracture. The root has an odour like a mixture of bruised pea-pods and orange-peel. Its taste is first like that of green peas; this soon disappears, and gives rise to a tingling sensation. The stem is 1/2 inch in diameter near the root, narrowing to 1/4 inch in the upper branches. The bark is thin, greyish-brown, longitudinally striated, and in some specimens sprinkled over with a number of white dots. The wood of the stem is yellowish-white and remarkably fibrous. The leaves (one of which is represented in the drawing) are imparipinnate, about 9 inches long, with from 3 to 5 pairs of opposite leaflets, which are articulated to the rachis, and have very short, slightly swollen petiolates. The rachis of the leaf is swollen at the base.

[Footnote 8: 3rd series, V, 581.]

The pairs of leaflets are usually about 1-1/4 inch apart, the lowest pair being about 4 inches from the base of the rachis. The leaflets are very variable in size, even on the same leaf. Their general outline is oblong-lanceolate. They are entire, with an emarginate or even retuse apex and an unequal base, and texture coriaceous. The veins are prominent on both sides of the leaf, and branch from the midrib at an obtuse angle in a pinnate manner. When held up to the light the leaflets are seen to be densely pellucidly punctate. These pellucid dots, which are receptacles of secretion, are not arranged, as in another kind of jaborandi, in lines along the veinlets, but are irregularly scattered all over the leaf, and appear equally numerous in every part. The whole plant is glabrous.”

Mr Holmes says there appear to be two varieties, if not species, of this _Pilocarpus_, the one being perfectly smooth in every part, as above described, and the other having the stems, petioles, and under surface of the leaves covered with a dense velvety pubescence composed of simple hairs.

=JAG′GERY.= _Syn._ PALM SUGAR. A coarse brown sugar made in India by the evaporation of the juice of several species of palms. The following are the principal varieties of this product:——

1. COCOA JAGGERY. From the juice of the Cocoa-nut palm (_Cocos nucifera_).

2. MALABAR JAGGERY. From the juice of the Gummuti palm (_Saguerus saccherifer_).

3. MYSORE JAGGERY. From the juice of the wild Date-palm (_Phœnix sylvestris_); 17 galls. yields 46 lbs.

4. PALMYRA JAGGERY. From the juice of the Palmyra palm (_Borassus flabelliformis_); 6 pints yield 1 lb.

=JA′LAP.= _Syn._ JALAPÆ RADIX, JALAPA, B. P. (Ph. L. & D.) CONVOLVULI JALAPÆ RADIX (Ph. E.), L. The dried tubercles of the _Exogonium purga_, _I. jalapa_——(Royle.) Jalap is a powerful stimulant and drastic purgative, producing copious liquid stools; but when judiciously administered, both safe and efficacious. It appears to be intermediate in its action between aloes and scammony.——_Dose_, 10 to 30 gr., in powder; in constipation, cerebral affections, dropsies, obstructed menstruation, worms, &c. Owing to its irritant properties, its use is contra-indicated in inflammatory affections of the alimentary canal, and after surgical operations connected with the abdomen and pelvis. It is usually administered in combination with sulphate of potassa or bitartrate of potassa and ginger; with mercurials, as the case may indicate. The powder is very generally adulterated.

=Jalap Biscuits.= 1. An ounce of jalap mixed with 16 ounces of the materials for gingerbread or other kind of cake.

2. Pure resin of jalap, 56 grams, powdered sugar and flour, 1000 grams; tincture of vanilla, 10 grams, white of egg, No. 20, yolk of egg, No. 40.

Let the resin be emulsified with the yolks of the egg, add successively the sugar, tincture, and flour, and mix thoroughly into a paste, with which thoroughly incorporate the whites of eggs, previously beaten up. Let the mass be divided into 144 biscuits, and bake.

=Jalap, Res′in of.= _Syn._ RESINA JALAPÆ, L. _Prep._ 1. (Ph. E.) See EXTRACT OF JALAP.

2. (Nativelle.) Jalap root is digested in boiling water for 24 hours, and after being reduced to thin slices more water is added, and the whole boiled for 10 minutes, with occasional agitation; the liquid is then expressed in a tincture press, and the boiling and pressing repeated a second and third time (these decoctions by evaporation yield AQUEOUS EXTRACT OF JALAP); the pressed root is next treated with rectified spirit, q. s., and boiled for 10 minutes, and then allowed to cool; the tincture is then pressed out, and the boiling with fresh alcohol and expression is repeated twice; a little animal charcoal is added to the mixed tinctures, and, after thorough agitation, the latter are filtered; the liquid is now distilled until nothing passes over, the supernatant fluid is poured off the fluid resin, and the latter dried by spreading it over the surface of the capsule, and continuing the heat. The product is a friable and nearly colourless resin, which forms a white powder resembling starch. _Prod._ Fully 10% of pure resin.

3. (Planche.) Resinous extract of jalap is dissolved in rectified spirit, the tincture agitated with animal charcoal, and after filtration gently evaporated to dryness.

_Pur._ The jalap resin of commerce is generally adulterated with scammony, gum, guaiacum or resin. When in a state of purity, it does not form an emulsion with milk, like scammony resin, but runs into a solid mass. It is insoluble in fixed oils and turpentine, whilst the common resins are freely soluble in those menstrua. Its alcoholic solution, dropped on a piece of absorbent white paper, and exposed to the action of nitrous gas, does not acquire a green or blue colour; if it does, guaiacum resin is present. 2% of this adulteration may be thus detected. (Gobley.) It is insoluble in ether; but guaiacum resin, common resin, and some others, are so; the decanted ether should not become opalescent when mixed with water, and should evaporate without leaving any residuum. Powdered jalap resin placed in cold water does not dissolve, but forms a semi-fluid, transparent mass, as if it had been melted. Dissolved in a watch-glass with a little oil of vitriol, a rich crimson-coloured solution is obtained, from which, in a few hours, a brown viscid resin separates. These last two characteristics distinguish it from other resins.

_Obs._ Earthenware or well-tinned copper vessels must alone be used in the above processes, as contact with copper or iron turns the resin black, and this tinge can only be removed by redissolving the resin in alcohol, the addition of animal charcoal, and re-evaporation.

Jalap resin is an energetic cathartic.——_Dose_, 1 to 5 gr. See JALAPIN.

=Jalap, Factitious Resin of.= _Syn._ RESINÆ JALAPÆ FACTITIA, L. A substance frequently sold for jalap resin is made by fusing a mixture of pale yellow resin and scammony resin, and adding, when it has cooled a little, but still semi-fluid, a few drops of balsam of Peru or tolu; the mixture is then poured into small paper capsules or tin moulds. Its effects resemble those of jalap resin, but it inflames less. (Landerer.)

=Jalap, Soap of.= _Syn._ SAPO JALAPÆ, SAPO JALAPINUS, L. _Prep._ (Ph. Bor.) Resin of jalap and Castile soap, of each 1 part; rectified spirit, 2 parts, or q. s. to dissolve the ingredients softened by a gentle heat; subsequently evaporate the mixture by the heat of a water bath until reduced to 4-1/2 oz., or it has acquired the consistence of a pill-mass.

_Prop., &c._ A greyish-brown mass, soluble in rectified spirit. Said to be milder in its action than the resin alone.——_Dose_, 5 to 15 oz.

=JALAP′IC ACID.= _Syn._ ODOROUS PRINCIPLE OF JALAP.——Pereira. _Prep._ Add an alcoholic solution of acetate of lead to a similar solution of jalap resin, collect the precipitate (jalapate of lead), and throw down the lead by means of sulphuretted hydrogen. (See ABSINTHIC ACID.) A brownish, soft, greasy substance, smelling strongly of jalap, soluble in alcohol and alkali, and slightly so in ether. Jalap resin contains about 13% of this substance.

=JAL′APIN.= C_{34}H_{56}O_{16}. _Syn._ JALAPINA. Jalap resin is commonly sold under this name, but pure jalapin is prepared by one or other of the following formulæ:——

_Prep._ 1. The liquid filtered from the jalapate of lead in preparing jalapic acid is a solution of acetate of jalapin, which, after any trace of lead is removed, by adding a few drops of dilute sulphuric acid, and filtration, yields the whole of its jalapin, as a precipitate, on the addition of 5 or 6 times its volume of water; this is collected, washed with a little cold distilled water, and dried by exposure to a current of warm dry air.

2. (Hume.) Coarsely powdered jalap is digested in strong acetic acid for 14 days, the tincture filtered ammonia added in excess, and the whole agitated strongly; the mixture is then filtered, the deposit washed in cold water, redissolved in acetic acid, reprecipitated by ammonia, and again washed and dried.

3. (Kayser.) Pure jalap resin, in powder, is digested for some time in boiling ether, by which means the jalapic acid is removed, and pure jalapin remains undissolved.

_Prop., &c._ A transparent, colourless, scentless, insipid resin, very soluble in alcohol, but insoluble in ether. It is the active purgative principle of crude jalap resin.

=JAMAI′CINE.= _Syn._ JAMAICINA. A peculiar alkaloid obtained by Huttenschmidt from the bark of the Cabbage-tree (_Andira inermis_).

_Prep._ The aqueous solution of cabbage-tree bark, treated with sulphuretted hydrogen and evaporated.

_Prop._ Yellow crystals soluble in water and, to a limited extent, in alcohol; fusible, and very bitter tasted. It forms salts with the acids, which, in small doses, produce restlessness and trembling; and in larger ones, purging. It is said to be vermifuge.

=JAMES’S POWDER.= See POWDERS.

=JAMS.= _Syn._ PRESERVES. Conserves of fruit with sugar, prepared by boiling. In the latter respect they differ from the conserves of the apothecary.

_Prep._ The pulped or bruised fruit is boiled along with 1/2 to 2/3 of its weight of loaf sugar, until the mixture jellies, when a little is placed on a cold plate; the semi-fluid mass is then passed through a coarse hair sieve whilst hot, to remove the stones and skins of the fruit, and as soon as it has cooled a little is poured into pots or glasses. It is usual to tie these over, when cold, with paper which has been dipped in brandy. The pots must then be placed aside in a dry and rather cold situation.

The following fruits are those from which jams are commonly prepared:——Apricots, cherries (various), cranberries, currants (black, red, and white), gooseberries (ripe and green), mulberries, Orleans plums, raspberries, and strawberries. Red currants are commonly added to the last, to remove insipidity.

=JAPAN′.= See VARNISH, and _below_.

=JAPAN′NING.= The art of covering paper, wood, or metal, with a coating of hard, brilliant, and durable varnish. The varnishes or lacquers employed for this purpose in Japan, China, and the Indian Archipelago, are resinous juices derived from various trees belonging to the natural order _Anacardiaceæ_, especially _Stagmaria verniciflua_, _Holigarna longifolia_, _Semecarpus Anacardium_, and species of _Rus_ (Sumach). For use, they are purified by a defecation and straining, and are afterwards mixed with a little oil, and with colouring matter, as required. In this country varnishes of amber, asphaltum, or copal, or mixtures of them, pass under the names of ‘JAPAN’ and ‘JAPAN VARNISH,’

_Proc._ The surface is coloured or painted with devices, &c., as desired, next covered with a highly transparent varnish (amber or copal), then dried at a high temperature (135° to 165° Fahr.), and, lastly, polished. Wood and paper are first sized, polished, and varnished. For plain surfaces, asphaltum, varnish or japan is used. See VARNISHING.

=JAPON′IC ACID.= C_{12}H_{10}O_{5}. When catechu is exposed to the air in contact with caustic alkalies, black solutions (alkaline japonates) are formed; with carbonated alkalies, red solutions (alkaline rubates); the acid of the former may be separated. It is a black powder, insoluble in water, soluble in alkalies, and precipitated by acids. Buric acid forms red insoluble compounds with the earths and some other metallic oxides.

=JARAVE.= The Spanish name for SARSAPARILLA BEER. See BEERS (in _pharmacy_).

=JASPER.= _Syn._ IASPIS, L. A mineral of the quartz family, occurring in rocky masses. It takes various shades of red, yellow, brown, and green, and is occasionally banded, spotted, or variegated. It was formerly used as an amulet against hæmorrhages and fluxes. It is now extensively worked up into rings, seals, snuff-boxes, vases, &c., for which it is well calculated from its extreme hardness and susceptibility of receiving a fine polish.

=JATRO′PHIC ACID.= _Syn._ CROTONIC ACID, IATROPHIC A. A peculiar fatty acid discovered by Pelletier and Caventon, and originally regarded by them as the cathartic principle of croton oil and croton seeds, but since shown by Redwood and Pereira to be nearly inert.

_Prep._ The oil is saponified by caustic potassa, and the resulting soap is decomposed by tartaric acid; the fatty matter which floats on the surface of the liquid is then skimmed off the aqueous portion, and the latter submitted to distillation; the liquid in the receiver is a solution of jatrophic acid.

_Prop., &c._ Volatile; very acid; has a nauseous odour; is solid at 23°, and vaporizes at 35° Fahr. It forms salts with the bases, none of which possess any practical importance.

=JAU′MANGE.= _Prep._ From isinglass, 1 oz.; boiling water, 12 oz.; dissolve, add of any sweet white wine, 1/2 pint; the yolks of 2 eggs beaten to a froth, and the grated yellow peel of two lemons; mix well, and heat the whole over the fire until sufficiently thickened, stirring all the time; lastly, serve it up or pour it into moulds.

=JAUN′DICE.= _Syn._ ICTERUS, MORBUS LUTEOLUS, L. A disease characterised by a yellow colour of the eyes and skin, deep-coloured urine, and pale alvine evacuations. It appears to arise from a disordered action of the biliary organs. The treatment consists of the administration of saline aperients, and small doses of blue-pill, followed by tonics and diaphoretics. The action of these remedies should be promoted by the copious use of diluents (particularly saline water), and exertion in the open air, when possible. When there is much pain and vomiting, anodynes (or opium, morphia, &c.) may be administered. Jaundice is not in itself a dangerous disease, but it sometimes lays the patient open to attacks of others which are so.

_Animals._——Jaundice affects cattle, giving rise to a tawny hue of the skin and membranes. Pleuro-pneumonia is frequently followed by jaundice. The best remedies are large doses of Epsom salts combined with ginger; and if these fail to remove the costiveness, a drachm of calomel should be added. If necessary, the above purge must be repeated next day, the action being assisted by giving the animal warm fluids.

Tonics and stimulants are also sometimes superadded to the above treatment.

=JEL′LY.= _Syn._ GELATINA, L. A term now very loosely applied to various substances which are liquid or semi-liquid whilst warm, and become gelatinous on cooling.

Jellies are coloured by the addition of the usual stains used by confectioners, and are rendered transparent by clarification with white of egg.

=Jelly, Almond.= _Syn._ GELATINA AMYGDALARUM, L. _Prep._ From rich almond milk, 1/4 pint; thick hartshorn jelly, 1/2 pint; sugar, 2 oz.; with 2 or 3 bitter almonds and a little lemon peel, to flavour, heated together, strained, and moulded.

=Jelly, Ar′row-root.= _Syn._ GELATINA MARANTÆ, L. From arrow-root, 1-1/2 oz., to water, 1 pint. Tous les mois jelly is made in the same way.

=Jelly, Bis′cuit.= _Prep._ From white biscuit (crushed beneath the rolling-pin), 4 oz.; cold water, 2 quarts; soak for some hours, boil to one half, strain, evaporate to 1 pint, and add, of white sugar, 3/4 lb., red wine, 4 oz., and cinnamon, 1 teaspoonful. In weakness of the stomach, and in dysentery and diarrhœa, and in convalescence combined with rich beef gravy or soup.

=Jelly, Bladder-wrack.= (Dr Russell.) _Syn._ GELATINA FUCI. _Prep._ Bladder-wrack (_Fucus vesiculosus_), 2 lbs.; sea water, 2 lbs.; macerate for 15 days. Applied to glandular tumours.

=Jelly, Bread.= _Syn._ PANADA; GELATINA PANIS, L. _Prep._ Cut a French roll into slices, toast them on each side, and boil in water, 1 quart, until the whole forms a jelly, adding more water if required; strain, and add sugar, milk, &c., to palate. It may be made with broth from which the fat has been skimmed, instead of water. Used as the last.

=Jelly, Broth.= _Syn._ SOUP-JELLY. From broth or soup from which the fat has been skimmed, evaporated until it becomes gelatinous on cooling. A few shreds of isinglass are commonly added. See SOUP (Portable).

=Jelly, Calves’ Feet.= _Prep._ For each foot take of water 3 pints, and boil to one half; cool, skim off the fat, and again boil for 2 or 3 minutes with the peel of a lemon and a little spice; remove it from the fire, strain through a jelly bag (see FILTRATION), add the juice of a lemon and a glass of wine, and when it has cooled a little put it into glasses or ‘forms.’

_Obs._ If this jelly is required to be very transparent it must be treated as follows:——After the fat is removed it should be gently warmed, just enough to melt it, next well beaten with the white of an egg and the seasoning, and then brought to a boil for a minute or two, when it will be ready for straining, &c. The calves’ feet should not be bought ready boiled, but only scalded. Cows’ feet (‘COW HEELS’) make nearly as good jelly as that from calves’ feet, and are much more economical.

=Jelly, Ceylon Moss.= _Syn._ GELATINA GRACILARIÆ, L. _Prep._ (Dr Sigmond.) Boil Ceylon moss (_Granularia lichenoides_), 1/2 oz. in water, 1 quart, for 25 minutes, or till the liquid jellies on cooling; strain and flavour. Very nutritious; recommended in irritation of the mucous membranes and phthisis.

=Jelly, Copaiba.= (M. Caillot.) _Syn._ GELATINA COPAIBA. _Prep._ Isinglass, 4 parts; water, 40 parts; dissolve in a water bath, and add 20 parts of sugar; pour the clear liquid jelly into a warm mortar, and add copaiba, 60 parts; triturate, and pour in a vessel to jelly. Flavour with some aromatic essential oil or balsam of tolu.

=Jelly, Cor′sican Moss.= _Syn._ GELATINA HELMINTHOCORTI, L. _Prep._ (P. Cod.) Corsican moss (_Gracilaria Helminthocorton_), 1 oz.; water, q. s.; boil 1 hour, and strain 8 fl. oz.; to this add of isinglass (previously soaked in a little water), 1 dr.; refined sugar, 2 oz.; white wine, a wine-glassful. Vermifuge. See DECOCTION.

=Jelly, Fruit.= Under this head we include those jellies made from the juices of fruits.

_Prep._ The strained juice mixed with 1/3 to 1/2 its weight of refined sugar, until it ‘jellies’ on cooling, observing to carefully remove the scum as it rises. The process should be conducted by a gentle heat, and it is preferable not to add the sugar until the juice is somewhat concentrated, as by lengthened boiling the quality of the sugar is injured.

_Obs._ Jellies are sold in pots or glasses, like JAMS. Both jams and fruit jellies are refrigerant and laxative; they are, however, mostly employed as relishes, especially during fevers and convalescences. The principal fruit jellies are:——APPLE, BARBERRY, CHERRY (from either Cornelian or Kentish cherries), CURRANT (black, white, and red), ELDERBERRY, GOOSEBERRY, PLUM, QUINCE, RASPBERRY. See LEMON and ORANGE JELLY.

=Jelly, Glycerin.= _Syn._ GELATINA GLYCERINI. Mix glycerin to the required consistence with compound tragacanth powder. Or take powdered gum Arabic, 1/2 oz.; syrup, 4 oz. (3 oz. of sugar to 1 oz. of water); the yolks of 3 eggs; olive oil, 4 oz.; glycerin, 2 oz. Rub the gum and syrup well together, add the yolks, and when mixed add the oil and glycerine, previously triturated together. Applied to chapped hands, abrasions, &c. See GLYCERIN OF STARCH.

=Jelly, Gra′′vy.= By evaporating meat gravies.

=Jelly, Harts′horn.= _Syn._ GELATINA CORNU CERVI, L. _Prep._ (P. Cod.) Hartshorn shavings, 8 oz.; wash it in water, then boil in clean water, 3 pints, till reduced to one half; strain, press, add of sugar, 4 oz., the juice of one lemon, and the white of an egg beaten up with a little cold water; mix well, clarify by heat, evaporate till it jellies on cooling, then add the peel of the lemon, and set it in a cool place. It may be flavoured with wine, spices, &c. Very nutritious.

=Jelly, Ice′land Moss.= _Syn._ GELATINA LICHENIS, L. _Prep._ (P. Cod.) Iceland moss, 2 oz.; soak for 1 or 2 days in cold water, then boil for 1 hour in water, q. s. to yield a strong solution; strain, decant the clear after repose, apply heat, and dissolve therein of isinglass, 1 dr.; evaporate the whole to a proper consistence, put it into pots, and set them in a cool place. Nutritious. Recommended in phthisis. The jelly of Iceland moss and cinchona (GELATINA LICHENIS CUM CINCHONA——P. Cod.) is made by adding to the above syrup of cinchona, 6 fl. oz.

=Jelly, Iceland Moss (Sweetened).= (P. C.) _Syn._ GELATINA LICHENIS SACCHARATA. _Prep._ Saccharated Iceland moss (see ICELAND MOSS, SACCHARATED), 7-1/2 oz.; sugar, 7-1/2 oz.; water, 15 oz.; orange-flower water, 1 oz. Boil the first three substances and remove the scum which forms, and then let the jelly flow into a vessel which contains the orange-flower water.

=Jelly, I′′rish Moss.= _Syn._ GELATINA CHONDRI, L. _Prep._ From Irish or carrageen moss. See DECOCTION.

=Jelly, I′′singlass.= _Syn._ CONFECTIONERS’ JELLY; GELATINA ICHTHYOCOLLÆ, L. _Prep._ From isinglass dissolved in water by boiling, and evaporated till it ‘jellies’ on cooling, adding flavouring, as desired. 1-1/2 oz. of good isinglass makes fully a pint of very strong jelly. See BLANCMANGE, ISINGLASS, CALVES-FEET JELLY, &c.

=Jelly, Lem′on.= From isinglass, 2 oz.; water, 1 quart; boil, add of sugar 1 lb., clarify, and when nearly cold add the juice of 5 lemons, and the grated yellow rinds of 2 oranges and of 2 lemons; mix well, strain off the peel, and put it into glasses.

=Jelly No′yeau.= As PUNCH JELLY, but strongly flavoured with bitter almonds.

=Jelly, Or′ange.= From orange juice, 1 pint; let it stand over the grated yellow rind of 3 or 4 of the oranges for a few hours, then strain, and add, of loaf sugar, 1/2 lb., or more, isinglass 1/2 oz., dissolved in water, 1 pint; mix, and put it into glasses before it cools.

=Jelly, Punch.= From isinglass, 2 oz.; sugar, 1-3/4 lb.; water, 1 pint; dissolve, add of lemon juice, 1/2 pint; the peels of 2 lemons and of 2 oranges; rum and brandy, of each 1/4 pint; keep it in a covered vessel until cold, then liquefy it by a very gentle heat, strain, and pour it into moulds. A pleasant and deceptive way of swallowing alcohol.

=Jelly, Quince.= (E. P., 1744.) _Syn._ GELATINA CYDONIORUM. _Prep._ Juice of quinces, 3 lbs.; sugar, 1 lb.; boil to a jelly.

=Jelly, Rice.= _Syn._ CRÊME DE RIZ. From rice boiled in water, sweetened, and flavoured.

=Jelly, Sago.= _Prep._ Soak sago in cold water for 1 hour, strain, and boil in fresh soft water until it becomes transparent; then add wine, sugar, clear broth, milk, or spices, to flavour. 1 oz. of sugar makes a pint of good jelly.

=Jelly, Salep.= (Soubeiran). _Syn._ GELATINA SALEPÆ. _Prep._ Ground salep, 4 dr.; sugar, 4 oz.; water, a sufficient quantity. Boil to 12 oz., and flavour to the taste.

=Jelly, Ta′pioca.= As SAGO JELLY, but using tapioca in lieu of sago.

=JERVINE.= C_{60}H_{5}N_{2}O_{5} An alkaloid discovered in 1837, by Simon, in the root of the _Veratrum album_, and by Mitchell, in 1874, in the root of the _Veratrum viride_. Dr H. C. Wood, jun., describing the physiological effects of jervine, says they consist “in general weakness, lowering of arterial pressure, a slow pulse, profuse salivation, and finally convulsions.” Jervine was analysed by Will, who ascribed to it the above composition.

=JES′UIT’S BARK.= See CINCHONA.

=JESUIT’S DROPS.= See DROPS.

=JESUIT’S POWDER.= Powdered cinchona bark.

=JET.= A variety of mineral bituminous carbon, very hard, and susceptible of a fine polish.

=JEW′ELS.= See DIAMOND, EMERALD, GEMS, &c.

=JEWEL′RY.= The gold in articles of jewelry, whether solid or plated, which are not intended to be exposed to very rough usage, is generally ‘coloured,’ as it is called in the trade. This is done as follows:——

1. (RED GOLD COLOUR.) The article, after being coated with the amalgam, is gently heated, and, whilst hot, is covered with gilder’s wax; it is then ‘flamed’ over a wood fire, and strongly heated, during which time it is kept in a state of continual motion, to equalise the action of the fire on the surface. When all the composition has burned away, the piece is plunged into water, cleansed with the ‘scratch-brush’ and vinegar, and then washed and burnished. To bring up the beauty of the colour, the piece is sometimes washed with a strong solution of verdigris in vinegar, next gently heated, plunged whilst hot into water, and then washed, first in vinegar, or water soured with nitric acid, and then in pure water; it is, lastly, burnished, and again washed and dried.

2. (OR-MOLU COLOUR.) This is given by covering the parts with a mixture of powdered hematite, alum, common salt, and vinegar, and applying heat until the coating blackens, when the piece is plunged into cold water, rubbed with a brush dipped in vinegar, or in water strongly soured with nitric acid, again washed in pure water, and dried. During this process, the parts not to be dried in ‘or-molu colour’ should be carefully protected.

The frauds practised in reference to the ‘fineness’ of the metal used in jewelry is noticed under GOLD (Jeweller’s). See also ASSAYING, DIAMOND, GEMS, GILDING LIQUOR, GILDING WAX, &c.

=JEW’S PITCH.= See ASPHALTUM.

=JOURNAL BOXES, Alloy for.= Copper, 24 parts; tin 24 parts; antimony, 8 parts. First melt the copper, then add the tin, and lastly the antimony.

=JUICE (Spanish).= See EXTRACT and LIQUORICE.

=JU′JUBE.= A fruit resembling a small plum, produced by various species of _Zizyphus_. Combined with sugar, it forms the JUJUBE PASTE of the shops, when genuine; but that now almost always sold under the name is a mixture of gum and sugar, slightly coloured and flavoured.

=JU′LEP.= _Syn._ JULAP; JULEPUM, JULEPUS, JULAPIUM, L. A term usually regarded as synonymous with ‘MIXTURE’; but according to the best authorities, implying a medicine which is used as a vehicle for other forms of medicine. The word comes through the French, from a Persian expression, which signifies ‘sweet drink.’ A julep, according to Continental writers, is a drink of little activity, generally composed of distilled waters, infusions, and syrups, to which mucilages and acids are sometimes added; “but never powders or oily substances, which could interfere with its transparency.” In England the juleps of old pharmacy are now classed under ‘MIXTURES,’

=JU′′NIPER BERRIES.= _Syn._ JUNIPERI BACCÆ, J. COMMUNIS BACCÆ (Ph. E.), JUNIPERUS (Ph. L.), L. The fruit of the _Juniperus communis_, or common juniper tree. In the old Ph. L. & D. both the tops and berries (JUNIPERI FRUCTUS ET CACUMINA——Ph. L. 1836; JUNIPERUS——BACCÆ, CACUMINA——Ph. D. 1862) were ordered. The berries are stomachic and diuretic, and have been long employed in dropsies, either alone or combined with foxglove and squills. The tops (SUMMITATES) have been highly praised in scurvy and certain cutaneous affections.——_Dose_, 1 to 2 dr., made into a conserve with sugar, or in the form of infusion or tea.

Douath found 100 parts of the berries to contain——

Water 29·44 Volatile oil ·91 Formic acid 1·86 Acetic acid ·94 Malic acid (combined) ·21 Oxalic acid traces Wax-like fatty matter ·64 Green resin (from ethereal solution) 8·46 Hard brown resin (from alcoholic solution) 1·29 Bitter principle (called juniperin) ·37 Pectin ·73 Albuminous substances 4·45 Sugar 29·65 Cellulose 15·83 Mineral substances 2·33 —————— 97·11

=JUN′KET.= _Syn._ DEVONSHIRE JUNKET, CURD JELLY. From warm milk put into a bowl, and then turned with a little rennet; some scalded cream and sugar are next added with a sprinkling of cinnamon on the top, without breaking the curd. Much esteemed by holiday folk in the western counties during the hot weather of summer. Sometimes, very strangely, a little brandy finds its way into these trifles.

=JUTE.= This is the fibre yielded by the _Corchorus capsularis_, a lime tree growing in India and China. It is the material of which sacks, gunny bags, and coarse thread are made. It mixes even with linen or cotton, and hence may not improbably be employed as a sophisticant of these substances.

The plates on page 930 exhibit the different microscopic appearances of the three substances.

=KALEIDOSCOPE.= _Syn._ FLOWER-GLASS. A pleasing philosophical toy invented by Sir David Brewster, which presents to the eye a series of symmetrical changing views. It is formed as follows:——Two slips of silvered glass, from 6 to 10 inches long, and from 1 to 1-1/2 inch wide, and rather narrower at one end than the other, are joined together lengthwise, by one of their edges, by means of a piece of silk or cloth glued on their backs; they are then placed in a tube of tin or pasteboard, blackened inside, and a little longer than is necessary to contain them, and are fixed by means of small pieces of cork, with their faces at an angle to each other that is an even aliquot part of 4 right angles (as the 1/6, 1/8, 1/10, &c.). The other end of the tube is then closed with an opaque screen or cover, through which a small eyehole is made in the centre; and the other end is fitted, first with a plate of common glass, and at the distance of about 1/8th of an inch, with a plain piece of slightly ground glass, parallel to the former; in the intermediate place or cell are placed the objects to form the images. These consist of coloured pieces of glass, glass beads, or any other coloured diaphanous bodies, sufficiently small to move freely in the cell, and to assume new positions when the tube is shaken or turned round. A tube so prepared presents an infinite number of changing and symmetrical pictures, no one of which can be exactly reproduced. This toy is so easily constructed, is so very inexpensive, and at the same time so capable of affording an almost inexhaustible fund of amusement to the young, that we advise our juvenile friends to try their hands at its construction. Any common tube of tin or pasteboard may be used, and strips of glass smoked on one side will answer for mirrors.

=KA′LI.= The name formerly applied to a species of _Salsola_ employed for making BARILLA. It is sometimes used as a designation for the crude alkalies, and is the German synonym for ‘potassa.’

=Kali, Acid′ulated.= _Syn._ LEMON AND KALI, LEMONATED K. A common preparation of the shops for making a pleasant effervescing draught. It is sometimes incorrectly styled ‘citrate of potash.’ _Prep._ 1. Carbonate of soda and tartaric acid, of each 5 oz.; lump sugar, 1 lb.; all in the state of fine powder, and separately dried by a very gentle heat, after which they are mixed together, flavoured with essence of lemon, 1 dr., rubbed through a gauze sieve in a warm dry situation, put into bottles, and corked down immediately.

2. Finely powdered white sugar, 16 lbs.; tartaric acid, 4-1/4 lbs.; carbonate of soda, 4 lbs.; essence of lemon, 1 oz.; as the last. Keeps well. A dessert-spoonful of either thrown into a glassful of water makes a pleasant effervescing draught.

=KA′LIUM.= [L.] Potassium.

=KAL′YDOR.= A cosmetic lotion; it resembles ‘GOWLAND’S LOTION,’ but is got up in a rather more pleasing style. See LOTION.

=KAMALA.= A powder consisting of the minute glands obtained from the capsules of the _Rottlera tinctoria_, a plant belonging to the nat. ord. _Euphorbiaceæ_. Kamala is imported from India, where it is known under the name of kameela. The rottlera, from which it is obtained, is a tree from 15 to 20 feet in height, indigenous to India and to many of the East Indian Islands.

Kamala has long been employed in India as a remedy for tapeworm, and within the last few years has been given for the same purpose in this country with very general success. It may be administered in doses of from thirty grains to three drachms, suspended in water, rubbed up with mucilage, or mixed with syrup. In large doses, such as three drachms, it sometimes purges violently. After the third or fourth motion the worm is generally evacuated dead. A second dose may be taken in about four hours should the first fail to act; or instead of a second dose, some castor oil may be given. Kamala is also used externally by the natives of India in various skin complaints, particularly in scabies. It is also said to have proved useful in herpetic ringworm.

Dr Anderson obtained from the resinous colouring matter, which is the principal constituent of kamala, a yellow crystalline substance, to which he gave the name _rottlerin_. The existence of rottlerin has since been confirmed by Mr Groves, who found that it becomes changed by exposure, a circumstance to which he attributes its non-detection in old specimens of the drug, and to which may very reasonably be attributed Leube’s failure to find it.

The ‘British Pharmacopœia’ ascribes the following ‘characters’ to kamala:——“A fine granular mobile powder, of a brick-red colour; it is with difficulty mixed with water, but when boiled with alcohol the greater part is dissolved, forming a red solution. Ether dissolves most of it, the residue consisting principally of tufted hairs. It should be free from sand or earthy impurities.”

Kamala forms a very considerable article of export from India, it being a valuable dye.

=KA′OLIN.= _Syn._ CHINA CLAY, PORCELAIN C. A fine white clay, derived from the decomposition of the felspar of granitic rocks. The potteries and porcelain works of this country are chiefly supplied with this substance from extensive tracts of it which occur near St Austie, Cornwall. See CLAY.

Elsner[9] gives the following process for distinguishing kaolin from ordinary clay:——He agitates it in a test-tube with pure strong sulphuric acid till a uniform mixture is produced, decants the acid after subsidence, dilutes it carefully with six volumes of water, and supersaturates the cooled solution with ammonia.

[Footnote 9: Dingl., ‘Pot. Journ.’ (Watts).]

Kaolin thus treated separates but slowly from the strong acid, and the diluted acid solution gives an immediate white precipitate with ammonia, whereas ordinary clay is but slightly attacked by the acid, separates quickly from it, and the acid after dilution gives but an insignificant precipitate with ammonia.

=KAP′NOMOR.= _Syn._ CAPNOMOR. A colourless oil obtained from crude kreasote by distillation with potassa. It boils at 360° Fahr., has a peculiar odour, and is insoluble in water, but readily soluble in an alkaline solution of kreasote.

=KATAL′YSIS.= _Syn._ CATALYSIS, CONTACT ACTION. Terms applied to a class of chemical actions in which the decompositions, and the recombination of the elements of compound bodies, is apparently excited by the mere presence of, or contact with, other bodies, which do not themselves suffer such a change.

=KAVA-KAVA.= See AVA.

=KELP.= The alkaline ashes obtained by burning various species of sea-weed, formerly much used for the preparation of carbonate of soda. The weeds most valued for the purpose are the _Fucus vesiculosus_, _nodosus_, and _serratus_, and the _Laminaria bulbosa_ and _digitata_.

Of late years the manufacture of kelp, like that of barilla, has been almost abandoned except as a source of iodine. Mr E. C. C. Stanford, by carefully collecting and compressing the weed, and afterwards submitting it to dry distillation, doubles the yield of iodine and bromine, and obtains in addition various valuable hydrocarbons. See BARILLA, IODINE, SODA, &c.

=KER′MES.= _Syn._ KERMES-GRAINS, ALKERMES; GRANUM TINCTORIUM, L. The dried bodies of the female _Coccus Ilicis_ of Linnæus, a small insect of the order _Hemiptera_, which flourishes on the Ilex oak. It has been used as a red and scarlet dye-stuff ever since the time of Moses; but is now superseded in this country by cochineal, which gives colours of much greater brilliancy.

=KER′MES MIN′ERAL.= _Syn._ KERMES MINERALE, K. MINERALIS, L. An amorphous tersulphide of antimony, containing a small admixture of teroxide of antimony and sulphuride of potassium. _Prep._ 1. IN THE HUMID WAY.——_a._ (P. Cod.) Carbonate of soda (cryst.), 128 parts (say 21 parts), is dissolved in water, 1280 parts (say 210 parts), contained in a cast-iron pan; tersulphide of antimony (in fine powder), 6 parts (say 1 part), is next added, and the whole boiled for an hour, with constant agitation with a wooden spatula; the boiling liquid is then filtered into a heated earthen pan containing a small quantity of very hot water, and the solution is allowed to cool as slowly as possible; the red powder which is deposited is collected on a cloth, on which it is well washed with cold water, and the superfluous water being removed by pressure, the powder is dried by a gentle heat, and is, lastly, passed through a fine silk-gauze sieve, and preserved from light and air.

_b._ (Wholesale.) From black sulphuride of antimony, 4 lbs.; carbonate of potassa, 1 lb.; boil in water, 2 galls., for half an hour, filter, &c., as before. The undissolved portion of sesquisulphuret of antimony may be boiled again several times with fresh potassa and water, until the whole is dissolved. Inferior to the last.

_c._ (CLUZELL’S KERMES.) From tersulphide of antimony, 4 parts; crystallised carbonate of soda, 90 parts; water, 1000 parts; boil, &c., as in 1, _a_, and dry the powder, folded up in paper, at a heat not exceeding 90° Fahr.

2. IN THE DRY WAY.——_a._ (P. Cod.) Carbonate of potassa, 100 parts; tersulphide of antimony, 50 parts; sulphur, 3 parts; mix, fuse in a Hessian crucible, pour the melted mass into an iron mortar, and when cold reduce it to powder; next boil it in water, 1000 parts, contained in an iron vessel, filter the solution, and otherwise proceed as before. _Product_: large, but of inferior quality.

_b._ (Fownes.) From tersulphide of antimony, 5 parts; carbonate of soda (dry), 3 parts; water, 80 parts; fuse, &c., as before. Nearly equal to 1, _a_.

_c._ (Berzelius.) Carbonate of potassa (pure), 3 parts, tersulphide of antimony, 8 parts; water, q. s. Resembles the last.

_Prop., &c._ An odourless, tasteless powder, insoluble in both water and alcohol, and, when pure and carefully prepared, entirely soluble in hydrosulphate of ammonia. As prepared by the formulæ 1, _a_, and 1, _c_, it is a very dark crimson powder, of a velvety smoothness; but that from the other formulæ has a brownish-red colour, more or less deep. The secret of preparing this compound of a fine and velvety quality, like that imported from the Continent, consists simply in filtering the solution whilst boiling hot, and allowing it to cool very slowly, by placing the vessel in an appropriate situation for that purpose. Another important point, according to Rose, is to employ sufficient alkali to keep the whole of the teroxide of antimony in solution as the liquid cools, instead of allowing a part of it to be deposited with the kermes. This is the reason of the superior quality and mildness of that prepared according to the directions of the French Codex. The liquor decanted from the ‘kermes mineral’ yields the golden sulphide of antimony on the addition of an acid, for which purpose the acetic is generally employed.

_Dose_, 1/2 gr. to 3 or 4 gr., as a diaphoretic, cathartic, or emetic. It occupies in foreign practice the place of our James’s Powder.

=KETCH′UP.= _Syn._ CATCHUP, CATSUP, KATCHUP. The juice of certain vegetables strongly salted and spiced, so as to be used as sauce; or a simple sauce made without the natural juice as a substitute for the true ketchup. The following are the principal varieties:——

=Ketchup, Camp.= _Prep._ Take of good old beer, 2 quarts; white wine, 1 quart; anchovies, 4 oz.; mix, heat it to the boiling-point, remove it from the fire, and add of peeled shalots, 3 oz.; mace, nutmegs, ginger, and black pepper, of each, bruised, 1/2 oz.; macerate for 14 days, with frequent agitation, then allow it to settle, and decant and bottle the clear portion.

=Ketchup, Cu′cumber.= _Prep._ From ripe cucumbers, in the same way as mushroom ketchup. Very luscious. Mixed with cream, or melted butter, it forms an excellent white sauce for fowls, &c.

=Ketchup, Marine′.= _Prep._ Take of strong old beer, 1 gall.; anchovies, 1-1/2 lb.; peeled shalots (crushed), 1 lb.; bruised mace, mustard seed, and cloves, of each 1/2 oz.; bruised pepper and ginger, of each 1/4 oz.; mushroom ketchup and vinegar, of each 1 quart; beat the mixture to the boiling point, put it into a bottle, and macerate for 14 days, frequently shaking; then strain through flannel, and bottle it for use. Excellent with anything; like the last, it makes good white sauce, and keeps well.

=Ketchup, Mush′room.= _Prep._ 1. Sprinkle mushroom flaps, gathered in September, with common salt, stir them occasionally for 2 or 3 days, then lightly squeeze out the juice, and add to each gallon cloves and mustard seed, of each, bruised, 1/2 oz.; allspice, black pepper, and ginger, of each, bruised, 1 oz.; gently heat to the boiling-point in a covered vessel, macerate for 14 days, and decant or strain. Should it exhibit any indications of change in a few weeks, bring it again to the boiling-point, with a little more spice, and a table-spoonful more salt.

2. Take of mushroom juice, 2 galls.; pimento, 2 oz.; cloves, black pepper, mustard seed, and ginger, of each, bruised, 1 oz.; salt, 1 lb. (or to taste); shalots, 3 oz.; gently simmer for 1 hour in a covered vessel, cool, strain, and bottle.

3. Take of mushroom juice, 100 galls.; black pepper, 9 lbs.; allspice, 7 lbs.; ginger, 5 lbs.; cloves, 1 lb. (all bruised); salt, q. s.; gently simmer in a covered tin boiler for 1 hour.

=Ketchup, Oys′ter.= _Prep._ Pulp the oysters, and to each pint add, of sherry wine, or very strong old ale, 1 pint; salt, 1 oz.; mace, 1/4 oz.; black pepper, 1 dr.; simmer very gently for 10 minutes, strain, cool, bottle, and to each bottle add a spoonful or two of brandy, and keep them in a cool situation. COCKLE KETCHUP and MUSSEL KETCHUP are made in the same way. Used to flavour sauces when the fish are out of season; excellent with rump steak, &c.

=Ketchup, Pon′tac.= _Prep._ Take of the juice of elderberries and strong vinegar, of each 1 pint; anchovies, 1/2 lb.; shalots and spice, q. s. to flavour; boil for 5 minutes, cool, strain, and bottle. Used to make fish sauces.

=Ketchup, Toma′to.= _Prep._ Prepared from tomatoes or love apples, like mushroom ketchup, except that a little very strong Chili vinegar is commonly added. An admirable relish for ‘high’ or rich flavoured viands.

=Ketchup, Wal′nut.= _Prep._ 1. Take of the expressed juice of young walnuts, when tender, 1 gall.; boil 10 minutes, skim, add of anchovies, 2 lbs.; shalots, 1 lb.; cloves and mace, of each 1 oz.; 1 clove of garlic, sliced; simmer in a covered vessel for 15 minutes, strain, cool, and bottle, adding a little fresh spice to each bottle, and salt, q. s. Will keep good in a cool place for 20 years.

2. Take of green walnut shells, 16 galls.; salt, 5 lbs.; mix and beat together for a week, press out the liquor, and to every gallon add, of allspice, 4 oz.; ginger, 3 oz.; pepper and cloves, of each 2 oz.; all bruised; simmer for half an hour, and set aside in a closed vessel and in a cool situation until sufficiently clear.

3. Take of walnut juice, 1 gall.; vinegar, 1 quart; British anchovies (sprats), 3 or 4 lbs.; pimento, 3 oz.; ginger, 1/4 oz.; long pepper, 1/2 oz.; cloves, 1 oz.; shalots, 2 oz.; boil and bottle, as before.

4. From the juice of walnut shells, 30 galls.; salt, 1 bushel; allspice and shalots, of each 6 lbs.; ginger, garlic, and horse-radish, of each 3 lbs.; essence of anchovies, 3 galls.; as before.

=Ketchup, Wine.= _Prep._ Take of mushroom or walnut ketchup, 1 quart; chopped anchovies, 1/2 lb.; 20 shalots; scraped horse-radish, 2 oz.; spice, q. s.; simmer for 15 minutes, cool, and add of white and red wine, of each 1 pint; macerate for 1 week, strain, and bottle.

_General Remarks._ In preparing the above articles, vessels of glazed earthenware, or stoneware, or well-tinned copper pans, should alone be used to contain them whilst being boiled or heated, as salt and vegetable juices rapidly corrode copper, and render the ketchup poisonous. Nothing in the shape of copper, lead or pewter should be allowed to touch them. Even a plated copper spoon left in a bottle of ketchup for some time will render its contents poisonous. Unpleasant and even dangerous fits of vomiting, colic, and diarrhœa have resulted from the neglect of this precaution. See SAUCE, &c.

=KIBES.= The vulgar name for ulcerated chilblains.

=KID′NEYS.= _Syn._ RENES, L. (In _anatomy_.) The kidneys, as almost every one knows, are abdominal viscera which secrete the urine, and form the great channels by which the effete nitrogenous matter is removed from the blood. They are subject to various affections, both functional and organic, chronic and acute, of which some are imperfectly understood, and others only admit of alleviation, but not of being cured. See URINE and URINARY AFFECTIONS.

=Kidneys.= (In _cookery_.) Soyer recommends kidneys to be dressed by gently broiling them, having previously split them, “so as nearly to divide them, leaving the fat in the middle,” and “run a skewer through them, that they may remain open.” After being rubbed with a little butter, and seasoned with salt and pepper, “they may be served on toast, or with any sauce.” “You may also egg and bread-crumb them.” “Five minutes suffice for a sheep or lamb’s kidney of common size.” (Soyer.) One or two lamb’s kidneys, plainly broiled and served up with the gravy in them, eaten along with a little dry-toasted bread, form a most excellent and appropriate luncheon or dinner for a dyspeptic or convalescent.

=KIESERITE.= A sulphate of magnesia found in the refuse salt (abraumsalz) of Stassfurth, near Magdeburg. It forms about 12% of the _abraumsalz_. It is employed for washing wool and for the manufacture of ‘permanent white’ by treatment with chloride of barium; also for the preparation of Glauber salts, and of hypochlorite of magnesia for bleaching linen. See LINEN.

=KING’S CUP.= _Prep._ Yellow peel of 1 lemon; lump sugar, 1-1/2 oz.; cold water, 1 pint; infuse 8 or 10 hours, and strain. The addition of a teaspoonful of orange-flower water is a great improvement. Used as a diluent in cases where acid liquors are inadmissible. See LEMONADE.

=KING’S EVIL.= See SCROFULA.

=KING’S YELLOW.= See YELLOW PIGMENTS.

=KI′NIC ACID.= HC_{7}H_{11}O_{6}. _Syn._ QUINIC ACID, CINCHONIC ACID. A peculiar monobasic acid occurring in the cinchona barks, in which it exists associated with the alkaloids.

Kinic acid is somewhat extensively diffused throughout the vegetable kingdom, being found in the bark of every species of the true cinchonas, as well as in the leaves of the oak, the elm, the ash, the ivy, the privet, and the coffee plant and berries. It occurs in the cinchona barks most probably combined with the alkaloids, which therefore exist in the plant as kinates.

It is readily obtained from kinate of lime by the action of dilute sulphuric acid; the filtered solution evaporated to the consistence of a syrup, gradually deposits large crystals resembling those of tartaric acid.

Henry and Plisson give the following directions for the preparation of kinic acid:——Make a decoction of cinchona bark with water containing some sulphuric acid, and filter whilst hot, and to the filtrate add gradually freshly precipitated oxide of lead, until the liquid becomes neutral, and changes from a red to a pale yellow colour; care must be taken to add sufficient oxide. The filtrate is freed from lead by passing sulphuretted hydrogen through it, and filtered milk of lime is then added to precipitate the quinine and cinchonine; and the filtered liquid is evaporated to a syrup, which yields on cooling crystalline calcic kinate. To separate the acid from the calcic salt, Berzelius directs an aqueous solution of the salt to be made and to be precipitated by basic acetate of lead; the washed precipitate, suspended in water, is then decomposed by sulphuretted hydrogen, and the solution filtered and evaporated. Or the calcium kinate may be decomposed by an aqueous or alcoholic solution of sulphuric acid.[10]

[Footnote 10: Watts.]

Kinic acid is, in the form of large tubular crystals, fusible at 161° C. These crystals dissolve in two parts of water; they are also soluble in spirits of wine, but scarcely, if at all, in ether.

It forms salts called kinates. Kinate of calcium is obtained from an acidulated infusion of cinchona bark, by adding an excess of lime, filtering, evaporating to a syrup, and setting the liquid aside to crystallise. These crystals are purified by re-dissolving them, treating the solution with a little animal charcoal, and crystallising the salt as before. The liquid from which the bark-alkaloids have been precipitated by hydrate of lime affords an almost inexhaustible supply of this salt. See KINONE.

=KI′NO.= _Syn._ GUM KINO; KINO (B. P., Ph. L. E. & D.) The juice flowing from the incised bark of the _Pterocarpus Marsupium_ or Indian, hardened in the sun.——_Dose_, 10 to 30 gr., in powder; as an astringent in chronic diarrhœa, &c.

=Kino, Factitious=, met with in the shops, is made as follows:——Logwood, 48 lbs.; tormentil root, 16 lbs.; madder root, 12 lbs.; exhaust by coction with water, q. s.; to the liquor add of catechu, 16 lbs.; dissolve, strain, and evaporate to dryness. _Prod._ 24 lbs. Extract of mahogany is also commonly sold for kino.

=KIRSCH′WASSER= (-văs ser) [Ger.]. _Syn._ KIRSCHENWASSER. A spirituous liquor distilled in Germany and Switzerland from bruised cherries. From the rude manner in which it is obtained, and from the distillation of the cherry-stones (which contain prussic acid) with the liquor, it has often a nauseous taste, and is frequently poisonous. When properly made and sweetened, it resembles noyeau.

=KISH.= An artificial graphite occasionally produced in iron-smelting furnaces. It occurs in brilliant scales, and is said to possess peculiar efficacy in certain forms of anæmia and chlorosis.

=KITCH′EN.= The late Alexis Soyer set down as one of the crying faults of our countrymen the employment of an apartment for the kitchen which is either too small or inconveniently situated, and which, in general, is not sufficiently provided with ‘kitchen requisites.’ “As a workman cannot work properly without the requisite tools, or the painter produce the proper shade without the necessary colours, in like manner does every person wishing to economise his food and to cook it properly require the proper furniture wherewith to do it.” The neglect of these matters, which is so general, is, undoubtedly, a mischievous and deceptive economy.

=KNIVES, to Clean.= After being used all knives should be wiped on a coarse cloth, so as to ensure their freedom from grease previous to being cleaned. The practice of dipping the blades in hot water not only fails to remove any grease that may be on them, but is almost sure to loosen the handles. It is very essential to remove any grease from them, since if this remain it will spoil the knife-board.

For cleaning knives, a proper knife-cleaning machine, purchased of a good maker, is best. But where this is not used, the knife-board ought to be covered with very thick leather, upon which emery powder should be placed. The emery gives a good polish to the knives, and does not wear them out so quickly as Bath-brick. When the points of the knives become worn very thin, they should be rounded by the knife-grinder. Where the handles are good it will sometimes be worth while to fit them to new blades.

=KNOX’S POW′DER.= _Prep._ From common salt, 8 parts; chloride of lime, 3 parts; mixed together. An ounce of it dissolved in a tumblerful of water furnishes a solution which is similar to Labarraque’s disinfecting fluid.

=KŒCHLIN’S LIQUID.= _Prep._ From copper filings, 96 gr.; liquor of ammonia, 2 fl. oz.; digested together until it turns of a full blue colour, and then mixed with hydrochloric acid, 5 fl. dr.; distilled water, 5 lbs.——_Dose_, 1 to 2 teaspoonfuls daily; in scrofula. It is poisonous in large doses.

=KOOCH′LA NUT.= See NUX VOMICA.

=KOU′MISS.= A liquor prepared by the Calmucs, by fermenting mare’s milk, previously kept until sour, and then skimmed. By distillation it yields a spirit called rack, racky, or araka. 21 lbs. of fermented milk yield about 3/4 pint of low wines, and this, by rectification, gives fully 1/4 pint of strong alcohol. It has lately come into use as a remedy for phthisis and general debility.

The following formula from the _Zeitschrift des Oesterr. Apoth. Ver._ (1876, 526), for the preparation of so-called KOUMISS EXTRACT, is said to be a good one:——

Powdered sugar of milk 100 parts Glucose (prepared from starch) 100 ” Cane sugar 300 ” Bicarbonate of potassium 36 ” Common salt 33 ”

Dissolve these ingredients in 600 parts of boiling fresh whey of milk, allow the solution to cool, then add 100 parts of rectified spirit, and afterwards 100 parts of strained fresh beer yeast. Stir the mixture well and put into bottles containing a quarter of a litre each. The bottles must be well corked and kept in a cool place.

For the preparation of Koumiss add 5 to 6 tablespoonfuls of this extract to a litre of skimmed, lukewarm milk, contained in a bottle of thick glass; cork well, keep the bottle for half a day in a moderately warm room (at 16°-20° C.), and afterwards in a cool cellar, shaking occasionally. The bottle should be filled to within 3-4 centimètres of the cork. After two days the Koumiss is ready for use.

=KOUS′SO.= _Syn._ CUSSO, KOSSO. This substance is the dried flowers of the _Brayera anthelmintica_, an Abyssinian tree which grows to the height of about 20 feet, and belongs to the natural order Rosaceæ. It is one of the most effective remedies known for both varieties of tapeworm. The dose for an adult is 3 to 5 dr., in powder, mixed with about half a pint of warm water, and allowed to macerate for 15 or 20 minutes. The method prescribed for its successful administration is as follows:——The patient is to be prepared by a purgative or a lavement, and the use of a very slight diet the day before. The next morning, fasting, a little lemon juice is to be swallowed, or a portion of a lemon sucked, followed by the dose of kousso (both liquid and powder), at 3 or 4 draughts, at short intervals of each other, each of which is to be washed down with cold water acidulated with lemon juice. The action of the medicine is subsequently promoted by drinking weak tea without either milk or sugar, or water flavoured with lemon juice or toasted bread; and if it does not operate in the course of 3 or 4 hours, a dose of castor oil or a saline purgative is taken.

The flavour of kousso is rather disagreeable and nauseating. Its operation is speedy and effectual; but at the same time it is apt to produce, in large doses, great prostration of strength, and other severe symptoms, which unfit it for administration to the delicate of both sexes, or during pregnancy or affections of the lower viscera. Care should be taken not to purchase it in powder, as, owing to its high price, it is uniformly adulterated. The powdered kousso of the shops is, in general, nothing more than the root-bark of pomegranate, coloured and scented.

=KRE′ASOTE.= _Syn._ CREASOTE, CREOSOTE, KREOSOTE; CREASOTUM (B. P., Ph. L. & D.), CREAZOTUM (Ph. E.), L. A peculiar substance, discovered by Reichenbach, and so named on account of its powerful antiseptic property. It is a product of the dry distillation of organic bodies, and is the preservative principle of wood smoke and pyroligneous acid.

_Prep._ Kreasote is manufactured from wood-tar, in which it is sometimes contained to the amount of 20% to 35%, and from crude pyroligneous acid and pyroxilic oil.

1. (P. Cod.) Wood-tar is distilled in a wrought-iron retort until white vapours of paraffin appear; the heavy oily matter which forms the lower layer of the product is collected, washed with water slightly acidulated with sulphuric acid, and then distilled in a glass retort, rejecting the first portions, which are chiefly eupion; the distillate is treated with a solution of potassa (sp. gr. 1·12), the mixed liquids being shaken strongly together; after it is settled, the layer of eupion which forms is removed from the surface, and the potash-solution of kreasote exposed to the air until it becomes black; it is then saturated with dilute sulphuric acid, the water liquid rejected, and the remainder (consisting of crude kreasote) submitted to distillation in glass; the treatment by exposure, potassa, sulphuric acid, and distillation is repeated three times or oftener, until the combination of kreasote and potassa ceases to become coloured by the action of the air; it is, lastly, saturated with concentrated phosphoric acid, and again distilled, rejecting the first portion that comes over.

2. (M. Simon.) A copper still, capable of containing 80 Berlin quarts, is filled to one third with the oil of wood-tar, and heat is applied; first, the more volatile matters pass over; these do not contain kreasote, and are, therefore, rejected; but when, by gradually increasing the temperature, there passes over a very acid liquid, which becomes turbid, and at the same time an oil separates from it when mixed with water, the product is collected, and the distillation continued until the operator notices a squirting in the still, when this part of the process is complete; the distilled product is then nearly saturated with potassa and returned to the still, which, in the meantime, has been well cleaned out, and about half filled with water, and the distillation is recommenced; at first an oil comes over, which floats on water, and which consists chiefly of eupion, and is, therefore, rejected; as soon, however, as the oil begins to sink in the water which comes over with it, it is charged with kreasote, and is carefully collected; the distilling aqueous fluid being reintroduced from time to time into the still, and the distillation continued so long as any oil continues to come over with it; the heavy oily distillate is now agitated with liquor of potassa, sp. gr. 1·120; the portion which remains undissolved is eupion, and is skimmed off; the potassa-solution of kreasote still, however, contains a considerable quantity of eupion, the greater portion of which may be separated by dilution and distillation with an equal quantity, or with at least 4/5ths of its volume of water, fresh water being added from time to time, as long as any eupion comes over with the distilled liquor; when this has ceased to pass over, sulphuric acid is poured into the still in quantity exactly sufficient to saturate 1/3rd only of the potassa formerly employed, and the distillation is again renewed; kreasote now distils over, the first portions of which, however, still contain eupion, after which pure kreasote follows; that is to say, “a kreasote which, when mixed with 6 or 8 times its quantity of a solution of pure potassa, furnishes a mixture which, by the addition of any further quantity whatever of water, does not become turbid.” The combination of kreasote remaining in the still is now mixed with sulphuric acid in slight excess, and the distillation renewed, the water coming over with it being from time to time returned into the still; and when no further oil passes over with the water, the process is complete. The kreasote thus obtained is redistilled with the water which has passed over with it, whilst the distilled water, as before, is allowed from time to time to run back into the still. The kreasote thus obtained is then colourless; but it contains a considerable quantity of water in solution, which is separated by distillation in a glass retort. The water distils first, and then kreasote, which, after cleaning the neck of the retort from the water, must be received in another dry receiver. If the kreasote assumes a red colour after being exposed for some time to the air, it must be re-distilled, and then it keeps very well. Korne found that tar prepared from turf furnishes much more kreasote than that from fir-wood, &c.

3. (Ure.) In operating upon pyroligneous acid, if we dissolve effloresced sulphate of soda in it to saturation, at the temperature of 267° Fahr., the kreasote separates, and floats upon the surface; it is then decanted, and left in repose for some days, during which it deposits a fresh portion of salt and vinegar; it is next saturated whilst hot with carbonate of potassa, and distilled along with water; a pale yellow oily liquid passes over, which is rectified with phosphoric acid, &c., like the crude product of kreasote from tar.

_Prop._ Kreasote is a colourless, transparent liquid, heavier than water, of a peculiar unpleasant penetrating odour resembling that of smoked meat, and a very pungent and caustic taste; its vapour irritates the eyes; it boils at 400° Fahr., and is still fluid at -16·6° Fahr.; it produces on white filter paper greasy spots, which disappear if exposed to a heat of 212° Fahr.; dissolves in 80 parts of water, and mixes in all proportions with spirit of wine, the essential and fatty oils, acetic acid, naphtha, disulphide of carbon, ammonia, and potassa; it dissolves iodine, phosphorus, sulphur, resins, the alkaloids, indigo blue, several salts (especially the acetates and the chlorides of calcium and tin); reduces the nitrate and acetate of silver; is resinified by chlorine, and decomposed by the stronger acids. The aqueous solution is neutral, and precipitates solutions of gum and the white of eggs. It kindles with difficulty, and burns with a smoky flame. When quite pure, it is unaltered by exposure to the air. Sp. gr. 1·071, at 68° Fahr. A slip of deal dipped into it, and afterwards in hydrochloric acid, and then allowed to dry in the air, acquires a greenish-blue colour. It turns a ray of polarised light to the right, whereas carbolic acid does not affect polarisation.

_Pur._ The fluid commonly sold in the shops for kreasote is a mixture of kreasote, picamar, and light oil of tar; in many cases it is little else than impure carbolic acid, with scarcely a trace of kreasote. Pure kreasote is perfectly soluble in both acetic acid and solution of potassa; shaken with an equal volume of water in a narrow test-tube, not more than the 1-80th part disappears; otherwise it contains water, of which kreasote is able to assume 1-10th without becoming turbid. If it can be dissolved completely in 80 parts by weight of water, at a medium temperature, it then forms a perfectly neutral liquid. An oily residue floating on the surface betrays the presence of other foreign products (EUPION, KAPNOMOR, PICAMAR), which are obtained at the same time with the kreasote during the dry distillation of organic substances.

Kreasote is “devoid of colour, has a peculiar odour, and is soluble in acetic acid. When it is dropped on bibulous paper, and a boiling heat is applied for a short time, it entirely escapes, leaving no transparent stain.” (Ph. L.) “Entirely and easily soluble in its own weight of acetic acid.” (Ph. E.) Sp. gr. 1·046 (Ph. L.), 1·066 (Ph. E. & D.). The density and boiling point of absolutely pure kreasote is given above. When prescribed in pills with oxide of silver, the mass will take fire unless the oxide be first mixed with liquorice or other powder. (Squire.)

_Uses._ Kreasote has been recommended in several diseases of the organs of digestion and respiration, in rheumatism, gout, torpid nervous fever, spasms, diabetes, tapeworm, &c.; but its use has not, in general, been attended with satisfactory results. It is given in the form of pills, emulsion, or an ethereal or spirituous solution. Externally it has been employed in various chronic diseases of the skin, sores of different kinds, mortifications, scalds, burns, wounds (as a styptic), caries of the teeth, &c.; mostly in the form of an aqueous solution (1 to 80); or mixed with lard (5 drops to 1 dr.), as an ointment; dissolved in rectified spirit, it forms a useful and a popular remedy for toothache arising from decay or rottenness. In the _arts_, kreasote is extensively employed to preserve animal substances, either by washing it over them, or by immersing them in its aqueous solution. A few drops in a saucer, or on a piece of spongy paper, if placed in a larder, will effectually drive away insects, and make the meat keep several days longer than it otherwise would. A small quantity added to brine or vinegar is commonly employed to impart a smoky flavour to meat and fish, and its solution in acetic acid is used to give the flavour of whisky to malt spirit. See CARBOLIC ACID.

=KRE′ATIN.= C_{4}H_{9}N_{3}O_{2}·Aq. _Syn._ CREATIN. A crystallisable substance obtained from the juice of the muscular fibre of animals. It was first obtained by Chevreul, but has recently been carefully studied by Liebig.

_Prep._ (Liebig.) Lean flesh is reduced to shreds, and then exhausted with successive portions of cold water, employing pressure; the mixed liquid is heated to coagulate the albumen and colouring matter of the blood, and is then strained through a cloth; pure baryta water is next added as long as a precipitate forms, the liquid is filtered, and the filtrate is gently evaporated to the consistence of a syrup; after repose for some days in a warm situation, crystals of kreatin are deposited; these are purified by redissolving them in water, agitating the solution with animal charcoal, and evaporating, &c., so that crystals may form.

_Prop., &c._ Brilliant, colourless, prismatic crystals; readily soluble in boiling water, sparingly so in cold water and in alcohol; the aqueous solution is neutral, bitter tasted, and soon putrefies.

=KREAT′ININ.= C_{4}H_{7}N_{3}O. This substance exists in small quantities, both in the juice of flesh and in conjunction with kreatin in urine. It is also produced by the action of the stronger acids on kreatin. It forms colourless prismatic crystals, which are soluble in water, and the solution has a strongly alkaline reaction. It is a powerful organic base, and produces crystallisable salts with the acids.

=KRE′NIC ACID.= See CRENIC ACID.

=KRYSTAL′LINE.= The name originally applied by Unverdorben to ANILINE.

=KUSTITIEN’S METAL.= _Prep._ Take of malleable iron, 3 parts; beat it to whiteness, and add of antimony, 1 part; Molucca tin, 72 parts; mix under charcoal, and cool. Used to coat iron and other metals with a surface of tin; it polishes without a blue tint, is hard, and has the advantage of being free from lead and arsenic.

=KYANI′ZING.= A method of preserving wood and cordage from decay, long known and practised; patented by Mr Kyan many years since. It consists in immersing the materials in a solution of corrosive sublimate, 1 part, and water, 50 or 60 parts, either under strong pressure or the contrary, as the urgency of the case or the dimensions of the articles operated on may require. See DRY ROT.

=KY′ANOL.= A substance obtained from coal-tar oil, and at first thought to be an independent principle, but since shown to be identical with ANILINE.

=LABARRAQUE’S FLUID.= See SOLUTION OF CHLORIDE OF SODA.

=LAB′DANUM.= _Syn._ LADANUM. An odorous, resinous substance found on the leaves and twigs of the _Cystus creticus_, a plant growing in the island of Candia and in Syria. It was formerly much used for making stimulating plasters. The following compound is often vended for it:——

=Labdanum, Facti′′tious.= _Prep._ From gum anime, resin, Venetian turpentine, and sand, of each 6 parts; Spanish juice and gum Arabic, of each (dissolved in a little water), 3 parts; Canada balsam, 2 parts; ivory black, 1 part; balsam of Peru, q. s. to give a faint odour.

=LA′BELS= capable of resisting the action of OILS, SPIRITS, WATER, SYRUPS and DILUTE ACIDS, may be obtained as follows:——Lay a coat of strained white of egg over the label (an ordinary paper one), and immediately put the vessel into the upper portion of a common steam-pan, or otherwise expose it to a gentle heat till the albumen coagulates and turns opaque, then take it out and dry it before the fire, or in an oven, at a white heat of about 212° Fahr.; the opaque white film will then become hard and transparent. The labels on bottles containing STRONG ACIDS or ALKALINE SOLUTIONS should be either etched upon the glass by means of hydrofluoric acid, or be written with incorrodible ink. See ETCHING and INK.

=LAB′ORATORY.= _Syn._ LABORATORIUM, L. A place fitted up for the performance of experimental or manufacturing operations in chemistry, pharmacy, and pyrotechny. For full information respecting the best mode of fitting up a chemical laboratory, the reader is referred to works especially devoted to chemical manipulation.[11] Almost any well-lighted spare room may be fitted up as a small laboratory at very little expense. The gas-furnaces and improved lamps introduced of later years have to a certain extent rendered chemists independent of brick furnaces. A strong working bench, fitted with drawers and cupboards, and having gas-pipes at intervals for attaching different kinds of jets, is an indispensable fixture. A close cupboard or closet, which is connected by a pipe with the chimney or the external air, is required to receive vessels emitting corrosive or evil-smelling vapours; the door of this closet should be of glass. A sink, with a copious supply of water, must be at hand, for washing apparatus. A glass, a stoneware barrel, with a tap of the same material, is required for holding distilled water. Shelves, supports for apparatus, and drawers, should be provided in abundance. The fine balances and other delicate instruments should be kept in a separate apartment. With regard to apparatus, we may state that the articles most frequently required in a laboratory are the gas or alcohol lamps; iron pans for sand bath and water bath; evaporating dishes; precipitating jars, funnels, and wash-bottles; retorts, flasks, and test-tubes; mortars and pestles; retort- and filtering-stands; rat-tail and triangular files, and glass rod and tubing.

[Footnote 11: The latest and best work is the ‘Handbook of Chemical Manipulation,’ by Greville Williams. Faraday’s famous work on the same subject has long been out of print.]

The principal philosophical instrument-makers sell chests or cabinets filled with apparatus and chemicals, under the name of ‘PORTABLE LABORATORIES,’ Those sold by Mr J. J. Griffin and by Messrs Jackson and Townson are, perhaps, the most complete. They are well adapted for illustrating all the more valuable facts of chemical science, and performing all the ordinary operations of qualitative analysis.

=LABURNINE.= A poisonous alkaloid, found in the unripe seeds of the laburnum plant, associated with another poisonous alkaloid called _Cytisine_.

=LAC.= _Syn._ LACCA, L. A resinous substance combined with much colouring matter, produced by the puncture of the female of a small insect, called the _Coccus lacca_ or _ficus_, upon the young branches of several tropical trees, especially the _Ficus Indica_, _Ficus religiosa_, and _Croton lacciferum_. The crude resinous exudation constitutes the STICK-LAC of commerce. SHELL-LAC or SHELLAC is prepared by spreading the resin into thin plates after being melted and strained. SEED-LAC is the residue obtained after dissolving out most of the colouring matter contained in the resin.

Shell-lac is the kind most commonly employed in the arts. The palest is the best, and is known as ‘orange-lac.’ The darker varieties——‘liver-coloured,’ ‘ruby,’ ‘garnet,’ &c.——respectively diminish in value in proportion to the depth of their colour.

_Uses, &c._ Lac was formerly much used in medicine; its action, if any, is probably that of a very mild diuretic. It is now chiefly used in DENTIFRICES, VARNISHES, LACQUERS, and SEALING-WAX.

=Lac, Bleached.= _Syn._ WHITE LAC; LACCA ALBA, L. By dissolving lac in a boiling lye of pearlash or caustic potassa, filtering and passing chlorine through the solution until all the lac is precipitated; this is collected, well washed and pulled in hot water, and, finally, twisted into sticks, and thrown into cold water to harden. Used to make pale varnishes and the more delicate coloured sealing-wax.

=LAC DYE.= _Syn._ LAC, LAC-LAKE, INDIAN COCHINEAL. A colouring substance used to dye scarlet, imported from India.

_Prep._ By dissolving out the colour of ground stick-lac by means of a weak alkaline solution, and then precipitating it along with alumina by adding a solution of alum.

_Obs._ To prepare the lac for dyeing, it is ground and mixed with diluted ‘lac spirit,’ and the whole allowed to stand for about a week. The ‘cloth’ is first mordanted with a mixture of tartar and ‘lac spirit,’ and afterwards kept near the boil for three quarters of an hour, in a bath formed by adding a proportion of the prepared lac dye to the mixture used for mordanting. Lac dye is only applicable to woollen and silk. The colours it yields are similar to those obtained from cochineal, but less brilliant.

=LAC SPIRIT.= See TIN MORDANTS.

=LACE.= This decorative fabric is made by interweaving threads of linen, cotton, or silk, into various patterns and designs. Although in some instances lace is made by hand, the greater part is now manufactured by machinery worked by steam or water. The hand-made lace was called bone, pillow, or bobbin lace, these two latter names having been given it from its having been woven upon a pillow or cushion by means of a bobbin. The manufactured article is bobbin net. Lace and the machinery by which it is produced is of so complex a nature that Dr Ure says of one particular form of it “it is as much beyond the most curious chronometer in the multiplicity of mechanical device as that is beyond a common roasting jack.”

Owing to the improvements in machinery introduced of late years, it may be mentioned that a piece of lace which twenty years since could only be produced at a cost of 3s. 6d. for labour, may now be turned out for 1d., and a quantity of the fabric which sold for £17, now realizes only 7s. A pair of curtains, each four yards long, may be made in one frame in two hours.

The following statistics relating to the British lace industry are of interest:——“In 1843 there were 3200 twist net and 800 warp frames, returning £2,740,000 that year; in 1851, 3200 bobbin net and 800 warp, giving a return of £3,846,000; and in 1866, 3552 bobbin and 400 warp, returning £5,130,000. There has since been no actual census, but about the same number is now at work, and the returns and profits are greatly increased by improved quality and patterns of goods produced. The returns of 1872 were certainly £6,000,000 at least; and from advancing wages and demand for Lever’s laces, must still rapidly increase. Men are now earning by making them from £4 to £6 for 56 hours’ weekly labour.”[12]

[Footnote 12: ‘British Manufacturing Industries.’ Stanford.]

=Lace, Gold and Silver, to Clean.= Reduce to fine crumbs the interior of a 2-lb. stale loaf, and mix with them 1/4 lb. of powder blue. Sprinkle some of this mixture plentifully on the lace, afterwards rubbing it on with a piece of flannel. After brushing off the crumbs rub the lace with a piece of crimson velvet.

=Lace, to Scour.= Take a perfectly clean wine bottle; wind the lace smoothly and carefully round it; then gently sponge it in tepid soap and water; and when clean, and before it becomes dry, pass it through a weak solution of gum and water. Next pick it out and place it in the sun to dry. If it be desired to bleach the lace, it should be rinsed in some very weak solution of chloride of lime, after removal from which it must be rinsed in cold water. Starch and expose it; then boil and starch, and again expose it if it has not become sufficiently white.

The following method is also said to whiten lace:——It is first ironed slightly, then folded and sewn into a clean linen bag, which is then placed for 24 hours in pure olive oil. Afterwards the bag, with the lace in it, is to be boiled in a solution of soap and water for 15 minutes, then well rinsed in lukewarm water, and finally dipped in water containing a small quantity of starch. The lace is then to be taken from the bag, and stretched on pins to dry.

To scour point lace proceed as follows:——“Fix the lace in a prepared tent, draw it tight and straight, make a warm lather of Castile soap, and with a fine brush dipped in rub over the lace gently, and when clean on one side do the same on the other; then throw some clean water on it, in which a little alum has been dissolved, to take off the suds; and, having some thin starch, go over with it on the wrong side, and iron it on the same side when dry; then open with a bodkin and set it in order. To clean the same, if not very dirty, without washing, fix it as before, and go over with fine bread, the crust being pared off, and when done, dust out the crumbs.” (Ernest Spon.)

Black lace may be cleaned by passing it through warm water containing some ox-gall, rinsing it in cold water, and then passing it through water in which a small quantity of glue has been previously dissolved by means of heat; it should then be taken out, clapped between the hands, and dried on a frame.

=LAC′QUER.= A solution of shell-lac in alcohol, tinged with saffron, annotta, aloes, or other colouring substances. It is applied to wood and metals to impart a golden colour. See VARNISH.

=LACTALBU′MEN.= See CASEIN.

=LAC′TATE.= _Syn._ LACTAS, L. A salt of lactic acid. The lactates are characterised by yielding an enormous quantity of perfectly pure carbonic oxide gas when heated with 5 or 6 parts of oil of vitriol. Most of these salts may be directly formed by dissolving the hydrate or carbonate of the metal in the dilute acid.

=LACTA′TION.= See INFANCY, NURSING, &c.

=LACTIC ACID.= H_{2}C_{6}H_{10}O_{6}. _Syn._ ACID OF MILK; ACIDUM LACTICUM, L. A sour, syrupy liquid, discovered by Scheele in whey. It is also found in some other animal fluids, and in several vegetable juices, especially in that of beet-root.

Lactic acid is by no means an unimportant constituent of the human organism. It is contained in the gastric juice, and is frequently formed in the sweat. It has also been detected in the saliva of persons suffering from diabetes. A modification of the acid, termed sarkolactic acid, occurs in the fluids of the muscular tissue.

It is likewise a product of the fermentation of many vegetable juices, such as turnips, carrots, beet-root, and cabbage, which latter vegetable, after undergoing the lactic fermentation, becomes converted into the sauer kraut of the Germans.

In the form of calcic lactate it occurs in nux vomica.

_Prep._ 1. Dissolve lactate of barium in water, precipitate the barium with dilute sulphuric acid, carefully avoiding excess, and gently evaporate to the consistence of a syrup, or until it acquires the density 1·215. Lactate of calcium may be used instead of lactate of barium, in which case a solution of oxalic acid must be employed as the precipitant. Pure. (See No. 5.)

2. Milk (skimmed or stale), 1 gall.; bicarbonate of sodium, 1/2 lb.; dissolve and expose the liquid to the air for some days, until it becomes sour, then saturate the excess of acid with some more bicarbonate of sodium, and again expose it to the air; repeat this as often as the liquid becomes sour; next heat the liquid to the boiling point, filter, evaporate to dryness (or nearly), and exhaust the residuum with rectified spirit; filter the alcoholic solution, which contains lactate of sodium, add sulphuric acid as long as it causes a precipitate to form, again filter, and concentrate the clear liquid by evaporation.

3. (Boutron and Fremy.) Milk, 3 or 4 quarts; sugar of milk, 200 to 300 gr.; mix, and expose for 2 or 3 days in an open vessel at 70° to 80° Fahr., then saturate with bicarbonate of sodium, again expose at a moderate temperature, saturate with more bicarbonate of sodium, and repeat the process until the whole of the sugar of milk is decomposed; then coagulate the casein by heat, filter, evaporate, extract the acid lactate of sodium by alcohol of sp. gr. ·810, and decompose it by the cautious addition of dilute sulphuric acid; again filter, distil off the alcohol, and evaporate as before.

4. (Scheele.) Evaporate sour whey to 1/8th of its bulk, saturate with slaked lime, filter, add 3 or 4 times the quantity of water, cautiously precipitate the lime with a solution of oxalic acid, filter, and gently evaporate to dryness in a warm bath; digest the residuum in strong rectified spirit, and again filter and evaporate.

5. (Wackenroder.) Sugar of lead, 25 parts; finely powdered chalk, 20 parts; skimmed milk, 100 parts; water, 200 parts; digested together at about 75° Fahr. In six weeks the chalk will be dissolved; the whole is then heated, but not to boiling; the cheese is strained off, pressed, and the decanted liquid is clarified by albumen and evaporated, to let the lactate of calcium crystallise; the salt is recrystallised and decomposed, either by sulphuric acid or by the exact quantity of oxalic acid. This is, perhaps, the most effective mode of preparing lactic acid.

6. (Wholesale.)——_a._ Good raw cane-sugar, 7 lbs., is dissolved in milk (skimmed or stale), 2 galls., and cheese (in a moist or putrescent state), 1/2 lb., and chalk, 4 lbs., previously rubbed to a cream with water, 1-1/2 gall., is then added; the mixture is then exposed in a loosely covered jar, at a temperature of 80° to 86° Fahr., with occasional stirring, for 2 or 3 weeks, or until the whole is converted into a semi-solid mass of crystals of lactate of calcium; this is purified either by draining off and expressing the liquid portion, dissolving the residue in water, and evaporating the solution for crystals; or the whole is put into a stoneware vessel and heated to the boiling-point, by which the casein is coagulated, and the lactate of calcium is dissolved; the solution filtered whilst hot, furnishes the salt in crystals on cooling; these crystals are subsequently dissolved in water, and the filtered solution decomposed by oxalic acid, as before.

_b._ From cane-sugar, 4 parts; moist cheese, 1 part; chalk, 3 parts; water, 20 parts; as the last.

_Obs._ Lactic acid prepared by any of the used formulæ may be rendered quite pure by dilution with water, saturation with baryta, evaporation, crystallisation, re-solution in water, and the careful addition of dilute sulphuric acid, as in No. 1; the liquid is, lastly, again filtered and evaporated. Another plan is to convert the acid into lactate of zinc, by the addition of commercial zinc-white, and to redissolve the new salt in water, and then decompose the solution with a stream of sulphuretted hydrogen. In all cases the evaporation should be conducted at a very gentle heat, and, when possible, finished over sulphuric acid, or _in vacuo_. For particular purposes this last product must be dissolved in ether, filtered, and the ether removed by a very gentle heat. Care must also be taken to remove the solid lactate of calcium at the proper period from the fermenting liquid, as otherwise it will gradually redissolve and disappear, and on examination the liquid will be found to consist chiefly of a solution of butyrate of calcium.

_Prop._ The product of the above formulæ is a solution of lactic acid. It may be concentrated _in vacuo_ over a surface of oil of vitriol until it appears as a syrupy liquid of sp. gr. 1·215; soluble in water, alcohol, and ether; exhibiting the usual acid properties, and forming salts with the metals, called LACTATES. Heated in a retort to 266° Fahr.; a small portion distils over, and the residuum on cooling concretes into a yellowish, solid, fusible mass, very bitter, and nearly insoluble in water. This is lactic acid, which has lost half (1 equiv.) of its basic water. By long boiling in water this substance is reconverted into lactic acid. Heated to 480° Fahr., it suffers decomposition, lactide (the anhydrous, concrete, or sublimed lactic acid of former writers) and other products being formed. This new substance may be purified by pressure between bibulous paper and solution in boiling alcohol from which it separates in dazzling white crystals on cooling. By solution in hot water and evaporation to a syrup, it furnishes common lactic acid.

_Uses._ Lactic acid has been given in dyspepsia, gout, phosphatic urinary deposits, &c. From its being one of the natural constituents of the gastric juice, and from its power of dissolving a considerable quantity of phosphate of calcium, it appears very probable that it may prove beneficial in the above complaints.——_Dose_, 1 to 5 gr.; in the form of lozenges, or solution in sweetened water.

=LAC′TIC FERMENTA′TION.= The peculiar change by which saccharine matter is converted into lactic acid. Nitrogenous substances, which in an advanced state of putrefactive change act as alcohol-ferments, often possess, at certain periods of their decay, the property of inducing an acid fermentation in sugar, by which that substance is changed into lactic acid. Thus, the nitrogenised matter of malt, when suffered to putrefy in water for a few days only, acquires the power of acidifying the sugar which accompanies it; whilst in a more advanced state of decomposition it converts, under similar circumstances, the sugar into alcohol. The gluten of grain behaves in the same manner. Wheat flour, made into a paste with water, and left for four or five days in a warm situation, becomes a true lactic acid ferment; but if left a day or two longer, it changes its character, and then acts like common yeast, occasioning the ordinary panary or vinous fermentation. Moist animal membranes, in a slightly decaying condition, often act energetically in developing lactic acid. The rennet employed in the manufacture of cheese furnishes a well-known example of this class of substances.

In preparing lactic acid from milk, the acid formed, after a time, coagulates and renders insoluble the casein, and the production of the acid ceases. By carefully neutralising the free acid by carbonate of sodium, the casein becomes soluble, and resuming its activity, changes a fresh quantity of sugar into lactic acid, which may be also neutralised, and by a sufficient number of repetitions of this process all the sugar of milk present may, in time, be acidified. This is the rationale of the common process by which lactic acid is obtained. Cane-sugar (probably by previously becoming grape-sugar) and the sugar of milk both yield lactic acid; the latter, however, most readily, the grape-sugar having a strong tendency towards the alcoholic fermentation. If the lactic fermentation be allowed to proceed too far, the second stage of the process of transmutation commences, hydrogen gas and carbonic acid gas are evolved, and the butyric fermentation, by which oily acids are formed, is established.

Pasteur ascribes the lactic fermentation to the agency of a specific kind of ferment, which occurs in the form of a greyish layer deposited upon the surface of the sediment formed during the fermentation of the sugar, casein, and chalk (see Lactic acid, _b_), in the manufacture of lactic acid.

If to a mixture of yeast, or any nitrogenous substance, and water, sugar, and then chalk, be added, and finally a very small quantity of this greyish substance, taken from a portion of a liquid undergoing active lactic fermentation, lactic acid fermentation is almost immediately set up, the chalk disappears owing to the formation of calcic lactate, and the greyish substance is copiously deposited. When placed under the microscope this ferment is seen to be composed of “little globules, or very short articulations, either isolated or in threads, constituting irregular flocculent particles, much smaller than those of beer yeast, and exhibiting a rapid gyratory motion.” If these little particles be washed thoroughly in pure water, and then placed in a solution of sugar, lactic acidification immediately commences in the saccharine liquid, and goes on steadily until stopped by the excess of free acid.

=LAC′TIDE.= See LACTIC ACID.

=LAC′TIN.= See SUGAR OF MILK.

=LAC′TOMETER.= _Syn._ GALACTOMETER. An instrument for ascertaining the quality of milk. Milk may be roughly tested by placing it in a long graduated tube sold for the purpose, and allowing it to remain until all the cream has separated and measured, then decanting off the clear whey, and taking its specific gravity; the result of the two operations, when compared with the known quantity of cream and the density of the whey of an average sample of milk, gives the value of the sample tested. See MILK.

A little instrument called a ‘milk-tester’ is sold in London at a low price. It is essentially a hydrometer which sinks to a given mark on the stem in pure water, and floats at another mark at the opposite end of the scale in pure milk. The intermediate space indicates the quantity of water (if any) employed to adulterate the article. As the sp. gr. of pure milk varies, the indications of the ‘tester’ cannot be depended on.

=LAC′TOSE.= See SUGAR OF MILK.

=LAC′TUCA.= (B. P.) _Syn._ LETTUCE. The leaves and flowering tops of the wild indigenous plant _Lactuca virosa_. They are sedative, narcotic, and powerfully diuretic; also mildly laxative and diaphoretic. Given in dropsy and visceral obstructions. See LETTUCE, EXTRACT OF.

=LACTUCA′′RIUM.= _Syn._ LETTUCE OPIUM. THRIDACE; LACTUCARIUM (Ph. E. & D.). The inspissated milky juice of the _Lactuca sativa_ (common garden lettuce), or the _Lactuca virosa_ (strong-scented wild lettuce), obtained, by incision, from the flowering stems, and dried in the air. The latter species yields by far the greatest quantity. M. Arnaud, of Nancy, adopts the following method of procuring this substance, which appears to be the most productive and simple of any yet published:——Before the development of the lateral branches, the stems of twelve plants are cut, one after another, a little below the commencement of these branches; returning to the first one, a milky exudation is found on the cut portion, and on that which remains fixed in the earth; this milky exudation is adroitly collected with the end of the finger (or with a bone knife), which is afterwards scraped on the edge of a small glass; the same operation is performed on twelve other heads, and so on; on the third day it is repeated on every portion of the plant remaining in the ground, a thin slice being first cut off the top; this is done every day until the root is reached. As soon as the lactucarium is collected it coagulates; the harvest of each day is divided into small pieces, which are placed on plates, very near each other, but without touching, and allowed to dry for two days, after which they are set aside in a bottle. In this way 15 or 20 times the ordinary product is obtained.

_Prop., &c._ Lactucarium is anodyne, hypnotic, antispasmodic, and sedative, allaying pain and diminishing the force of the circulation. It has been recommended in cases in which opium is inadmissible, and has been administered with advantage in chronic rheumatism, colic, diarrhœa, asthma, and troublesome cough of phthisis, the irritability and watchfulness in febrile disorders, &c.——_Dose_, 2 to 5 gr.; made into pills, lozenges, or tincture.

=LACTU′CIN.= _Syn._ LACTUCINUM, L. This is the active principle of lactucarium, and is found in the juice of several species of lettuce.

_Prep._ Exhaust lactucarium with hot rectified spirit, agitate the tincture with a little animal charcoal, filter, add a little milk of lime, and evaporate to dryness; digest the residuum in hot rectified spirit; filter, and evaporate by a gentle heat, so that crystals may form.

_Prop., &c._ A nearly colourless, odourless, fusible, neutral, bitter substance; sparingly soluble in cold water and in ether, but freely soluble in alcohol. It possesses feeble basic properties. Good lactucarium contains fully 20% of this substance.

=LAD′ANUM.= See LABDANUM.

=LAENNEC’S CONTRA-STIMULANT.= See DRAUGHT.

=LAKE=. _Syn._ LACCA, L. Animal or vegetable colouring matter, precipitated in combination with oxide of tin or alumina; usually the latter. The term was formerly restricted to red preparations of this kind, but is now indiscriminately applied to all compounds of alumina and colouring matter. The term ‘LAKE,’ when unqualified by an adjective, is, however, understood to apply exclusively to that prepared from cochineal.

_Prep._ Lakes are made——1. By adding a solution of alum, either alone or partly saturated with carbonate of potassa, to a filtered infusion or decoction of the colouring substance, and after agitation precipitating the mixture with a solution of carbonate of potash.——2. By precipitating a decoction or infusion of the colouring substance made with a weak alkaline lye, by adding a solution of alum.——3. By agitating recently precipitated alumina with a solution of the colouring matter, prepared as before, until the liquid is nearly decoloured, or the alumina acquires a sufficiently dark tint. The first method is usually employed for acidulous solutions of colouring matter, or for those whose tint is injured by alkalies; the second, for those that are brightened, or at least uninjured, by alkalies; the third, for those colouring matters that have a great affinity for gelatinous alumina, and readily combine with it by mere agitation. By attention to these general rules, lakes may be prepared from almost all animal and vegetable colouring substances that yield their colour to water, many of which will be found to possess great beauty and permanence. The precise process adapted to each particular substance may be easily ascertained by taking a few drops of its infusion or decoction, and observing the effects of alkalies and acids on the colour. The quantity of alum or of alumina employed should be nearly sufficient to decolour the dye liquor; and the quantity of carbonate of potassa should be so proportioned to the alum as to exactly precipitate the alumina without leaving free or carbonated alkali in the liquid. The first portion of the precipitate has the deepest colour, and the shade gradually becomes paler as the operation proceeds. A beautiful ‘tone’ of violet, red, and even purple, may be communicated to the colouring matter of cochineal by the addition of perchloride of tin; the addition of arseniate of potassa (neutral arsenical salt) in like manner gives shades which may be sought for in vain with alum or alumina. After the lake is precipitated, it must be carefully collected, washed with cold distilled water, or the purest rain water, until it ceases to give out colour, and then carefully dried in the shade. In this state it forms a soft velvety powder. That of the shops is generally made up into conical or pyramidal drops (drop lake), which is done by dropping the moist lake through a small funnel on a clean board or slab, and drying it by a gentle heat as before. A very little clear gum water is commonly added to the paste to give the drops consistence when dry.

=Lake, Blue.= _Syn._ LACCA CŒRULEA, L. Prepared from some of the blue-coloured flowers; fugitive. The name is also applied to lump archil (lacca cœrulea), to moist alumina coloured with indigo, and to mixed solutions of pearlash and prussiate of potash, precipitated with another solution of sulphate of iron and alum. These are permanent and beautiful, but are seldom used, in consequence of indigo and Prussian blue supplying all that is wanted in this class of colours.

=Lake, Brazil-wood.= _Syn._ DROP LAKE; LACCA IN GLOBULIS, L. _Prep._ 1. Take of ground Brazil-wood, 1 lb.; water, 4 galls.; digest for 24 hours, then boil for 30 or 40 minutes, and add of alum, 1-1/2 lb., dissolved in a little water; mix, decant, strain, and add of solution of tin, 1/2 lb.; again mix well and filter; to the clear liquid add, cautiously, a solution of salt of tartar or carbonate of soda, as long as a deep-coloured precipitate forms, carefully avoiding excess; collect, wash, dry, &c., as directed above.

_Obs._ The product is deep red. By collecting the precipitate in separate portions, lakes varying in richness and depth of colour may be obtained. The first portion of the precipitated lake has the brightest colour. An excess of alkali turns it on the violet, and the addition of cream of tartar, on the brownish red. The tint turns more on the violet red when the solution of tin is omitted. Some persons use less, others more, alum.

2. Add washed and recently precipitated alumina to a strong and filtered decoction of Brazil wood. Inferior to the last.

=Lake, Carminated.= _Syn._ COCHINEAL LAKE, FLORENCE L., FLORENTINE L., PARIS L., VIENNA L.; LACCA FLORENTINA, L. _Prep._ 1. The residuum of the cochineal left in making carmine is boiled with repeated portions of water, until it is exhausted of colour; the resulting liquor is mixed with that decanted off the carmine, and at once filtered; some recently precipitated alumina is then added, and the whole gently heated, and well agitated for a short time; as soon as the alumina has absorbed sufficient colour, the mixture is allowed to settle, after which the clear portion is decanted, the lake collected on a filter, washed, and dried, as before. The decanted liquor, if still coloured, is now treated with fresh alumina until exhausted, and thus a lake of a second quality is obtained. Very fine.

2. To the coloured liquor obtained from the carmine and cochineal as above, a solution of alum is added, the filtered liquor precipitated with a solution of carbonate of potassa, and the alum or alumina; this brightens the lake collected and treated as before. Scarcely so good as the last.

_Obs._ Some makers mix a little solution of tin with the coloured liquor before adding colour. The above lake is a good glazing colour with oil, but has little body. It may be made directly from a decoction of cochineal. (See _below_.)

=Lake, Cochineal.= _Prep._ 1. Cochineal (in coarse powder), 1 oz.; water and rectified spirit, of each 2-1/2 oz.; digest for a week, filter, and precipitate the tincture with a few drops of solution of tin, added every two hours, until the whole of the colouring matter is thrown down; lastly, wash the precipitate in distilled water, and dry it. Very fine.

2. Digest powdered cochineal in ammonia water for a week, dilute the solution with a little water, and add the liquid to a solution of alum, as long as a precipitate falls, which is the lake. Equal to the last.

3. Coarsely powdered cochineal, 1 lb.; water, 2 galls.; boil 1 hour, decant, strain, add a solution of salt of tartar, 1 lb., and precipitate with a solution of alum. By adding the alum first, and precipitating the lake with the alkali, the colour will be slightly varied. All the above are sold as CARMINATED or FLORENCE LAKE, to which they are often superior.

=Lake, Green.= Made by mixing blue and yellow lake together. Seldom kept in the shops, being generally prepared extemporaneously by the artist on his palette.

=Lake, Lac.= _Prep._ Boil fresh stick-lac in a solution of carbonate of soda, filter the solution, precipitate with a solution of alum, and proceed as before.

=Lake, Lichen.= See ORCEIN.

=Lake, Madder.= _Syn._ LACCA RUBIÆ, L. COLUMBINA, L. _Prep._ 1. (Sir H. C. Inglefield.) Take of Dutch grappe or crop madder, 2 oz.; tie it in a cloth, beat it well in a pint of water in a stone mortar, and repeat the process with fresh water (about 5 pints) until it ceases to yield colour; next boil the mixed liquor in an earthen vessel, pour it into a large basin, and add of alum 1 oz., previously dissolved in boiling water, 1 pint; stir well, and while stirring, pour in gradually of a strong solution of carbonate of potassa (‘oil of tartar’), 1-1/2 oz.; let the whole stand until cold, then pour off the supernatant yellow liquor, drain, agitate the residue with boiling water, 1 quart (in separate portions), decant, drain, and dry. _Product_, 1/2 oz. The Society of Arts voted their gold medal to the author of the above formula.

2. Add a little solution of acetate of lead to a decoction of madder, to throw down the brown colouring matter, filter, add a solution of tin or alum, precipitate with a solution of carbonate of soda or of potassa, and otherwise proceed as before.

3. (Ure.) Ground madder, 2 lbs.; water, 1 gall.; macerate with agitation for 10 minutes, strain off the water, and press the remainder quite dry; repeat the process a second and a third time; then add to the mixed liquors, alum 1/2 lb., dissolved in water, 3 quarts; and heat in a water bath for 3 or 4 hours, adding water as it evaporates; next filter, first through flannel, and, when sufficiently cold, through paper; then add a solution of carbonate of potassa as long as a precipitate falls, which must be washed until the water comes off colourless, and, lastly, dried. If the alkali be added in 3 successive doses, 3 different lakes will be obtained, successively diminishing in beauty. See MADDER, MADDER, RED, &c.

=Lake, Or′ange.= _Prep._ Take of the best Spanish annotta, 4 oz.; pearlash, 3/4 lb.; water, 1 gall.; boil for half an hour, strain, precipitate with alum, 1 lb., dissolved in water, 1 gall., observing not to add the latter solution when it ceases to produce an effervescence or a precipitate; strain, and dry the sediment in small squares, lozenges, or drops. The addition of some solution of tin turns this lake on the LEMON YELLOW; acids redden it. See LAKE, YELLOW.

=Lake, Red.= _Prep._ Take of pearlash, 1 lb.; clean shreds of scarlet cloth, 3-1/2 lbs.; water, 5 galls.; boil till the cloth is decoloured, filter the decoction, and precipitate with a solution of alum, as before. See the LAKES noticed above (Brazil-wood, Carminated, Cochineal, and Madder).

=Lake, Yellow.= _Prep._ 1. Boil French berries, quercitron bark, or turmeric, 1 lb., and salt of tartar, 1 oz., in water, 1 gall., until reduced to one half, then strain the decoction, and precipitate with a solution of alum.

2. Boil 1 lb. of the dye-stuff with alum, 1/2 lb.; water, 1 gall., as before, and precipitate the decoction with a solution of carbonate of potash. See LAKE, ORANGE (_above_).

=LAMB= in its general qualities closely resembles mutton, of which, indeed, it is merely a younger and more delicate kind. It is well adapted as an occasional article of food for the convalescent and dyspeptic; but it is unequal for frequent use, more especially for the healthy and robust, to the flesh of the adult animal.

=LAMBS, DISEASES OF.= Among other diseases, these animals are particularly prone to one affecting the lungs, in consequence of the existence of parasites (_Strongylus bronchialis_) in the air-passages. See PARASITES.

=LAMP.= A contrivance for producing artificial light or heat by the combustion of inflammable liquids. The term ‘lamp’ is also applied to a portable gas-burner (GAS-LAMP), and to a tubular candle-holder, which, by the aid of a simple mechanical device, keeps the flame at one height (CANDLE-LAMP).

OIL LAMPS were employed for illumination among the nations of antiquity, at the earliest period of which any record exists. The Assyrian, Greek, and Roman lamps preserved in our museums are generally noble specimens of art-workmanship. Though elegant in form, and rich in external embellishment, the ancient lamp was simply a vessel to contain the oil, with a short depression or spout on the one side, in which the wick is laid. Lamps of this rude construction are still in common use in many countries.

No important improvement in the principle and construction of lamps as a source of light occurred until a comparatively recent date; the smoke, dirt, and disagreeable odour of the common lamp having previously led to its disuse among the superior classes in favour of candles. At length, in 1789, M. Argand made a revolution in illumination by the invention and introduction of the well-known lamp which bears his name. In the ARGAND LAMP a hollow tubular wick of woven cotton replaces the solid bundles of fibres, and is so arranged that air passes through it into the interior of the flame. Over the burner is placed a cylindrical glass chimney, open at the bottom, and surrounding the flame at a short distance from it, by which another current of air is made to act on the exterior portion of the flame. In this way a due supply of oxygen is secured, and sufficient heat generated for the perfect combustion of the gaseous products of the oil, and the smoke and soot which escape from the ordinary lamp are converted into a brilliant and smokeless flame.

The earliest table-lamps constructed on Argand’s principle had one serious defect——the oil vessels had to be placed almost on a level with the burners, in a position which caused them to cast objectionable shadows. This defect was almost entirely removed by making the oil vessel in the form of a flattish ring, connected by slender tubes with the burner. The more elegant contrivances, known as the MODERATOR LAMP and CARCEL LAMP, which are now so much used for burning colza and similar oils, cast no shadow. In these the oil, instead of being sucked up by the wick, or descending to it by the force of gravity, is driven up by mechanical means from the oil-reservoir contained in the foot or pedestal. A spiral spring, acting upon a piston, elevates the oil in the ‘moderator,’ while a little pump worked by clockwork does the same duty in the ‘Carcel.’ The burner and wick in each are formed on Argand’s principle.

For burning the hydrocarbon oils distilled from coal and petroleum, lamps of very simple construction are used. These oils, in consequence of their diffusive character, rise to a considerable height up a wick, and therefore do not require mechanical lamps. The wicks of HYDRO-CARBON LAMPS are usually flat, but sometimes circular. To cause perfect combustion, a strong draught of air is created by placing over the flame a tall glass chimney, usually much contracted above the flame. A metallic cap, with an orifice the shape of the flame, is placed over the burner, its use being to deflect the currents of air upon the flame. The reservoirs of hydro-carbon lamps ought always to be constructed of some bad conductor of heat, as glass or porcelain.

For chemical operations, many forms of lamp are used. The ordinary glass SPIRIT-LAMP, fitted with a ground-glass cap, is quite indispensable for minor experiments. (See _engr._ 1.) Stoneware wick-holders are preferable to those of brass, which become greatly heated, and endanger the splitting of the glass. “An effective spirit-lamp may at any time be constructed out of a vial having a glass tube passing through the cork, a cover being formed from a test-tube inverted over the wick, and fitting with moderate tightness on the superior extremity of the cork” (Greville Williams). Alcohol or wood spirit is the fuel used.

The ARGAND LAMP, when intended as a source of heat for chemical purposes, is so modified as to adapt it to burn either oil, spirit of wine, or wood-spirit, and the combustion is greatly aided by the chimney, which in this case is made of copper. (See _engr._ 2 and 3.) The lamp itself is also made of metal, and furnished with ground caps to the wick-holder and aperture by which the spirit is introduced, in order to prevent loss of spirit by evaporation when the lamp is not in use. When in use this aperture must always be left open, otherwise an accident is sure to happen, as the heat expands the air in the lamp, and the spirit is forcibly expelled.

In those situations in which coal-gas is cheap, it may be used with great economy and advantage as a source of heat in most chemical operations. Retorts, flasks, capsules, and other vessels, can be thus exposed to an easily regulated and constant temperature for many successive hours. Small platinum crucibles may be ignited to redness by placing them over the flame on a little wire triangle. Of the various gas-lamps now used in the laboratory, the first and most simple consists of a common Argand gas-burner fixed on a heavy and low foot, and connected with a flexible gas-tube of caoutchouc or other material. (See _engr._ 4.) With this arrangement it is possible to obtain any degree of heat, from that of the smallest blue flame to that which is sufficient to raise a moderately large platinum crucible to dull redness. When gas mixed with a certain proportion of air is burnt, a pale blue flame, free from smoke, and possessing great heating power, is obtained. A lamp for burning the mixture may easily be made by fitting a close cover of fine wire gauze over the top of the chimney of the last-mentioned contrivance. The gas is turned on, and after a few minutes ignited above the wire gauze. (See page 946). The ingenious and useful burners of Bunsen and Griffin are so constructed that gas and air mixed in any proportions, or gas alone, may be burnt at pleasure. Bunsen’s is a most efficient and convenient form of burner. (See illustration on next page.) It consists of a gas jet, surrounded by a metal tube, about 6 to 9 inches high and about 1/2 inch in diameter; having at the bottom four large holes. On the admission of air, when the gas is turned on, the air rushes in by these orifices, and mingling with the gas, the mixture ascends to the top of the tube and is there ignited, giving rise to a flame of great heat, but without luminosity, owing to the simultaneous combustion of the carbon and the hydrogen. The burner, however, is so contrived that by shutting off the supply of air entirely, or limiting it, the flame may be made more or less luminous at pleasure. To distribute the flame, a rosette burner is placed on the top of the tube.

An improved variety of this burner has been designed by Bunsen, and is figured below.

It is so contrived as to give a flame that is a very much better substitute for the flame of the blowpipe, than the ordinary Bunsen’s burner, and may hence be employed for reducing, oxidising, fusing, and volatilising, as well as for the observation of coloured flames. Fig. 1 is a sheath which, by turning round, regulates the admission of air. When it is used the conical chimney, _d d d d_, is placed in _e e_; it is of a size sufficient to allow of the flame burning tranquilly. In fig. 1 the flame is represented of half its natural size. This flame it will be seen consists of three divisions, viz.——1, _a a a a_ the dark zone, which is composed of cold gas mixed with about 62 per cent. of air. 2, _a c a b_ the mantle formed by the burning mixture of gas and air. 3, _a b a_, the luminous tip of the dark cone, which only appears when the orifices for the air are partially closed. Reductions may be performed in this part of the flame.

Bunsen, however, divides the flame into six parts, to which he attributes as many functions. These six divisions of the flame he names as follows:——

1. _The base_ at α has a relatively low temperature, because the burning gas is here cooled by the constant current of fresh air, and also because the lamp itself conducts the heat away. This part of the flame serves for discovering the colours produced by readily volatile bodies, when less volatile matters which colour the flame are also present. At the relatively low temperature of this part of the flame, the former vaporises alone instantaneously, and the resulting colour imparted to the flame is for a moment visible unmixed with other colours.

2. _The Fusing Zone._ This lies at β, at a distance from the bottom of somewhat more than one third of the height of the flame, equidistant from the outside and the inside of the mantle, which is broadest at this part. This is the hottest part of the flame, viz., about 2300°, and it therefore serves for testing substances, as to their fusibility, volatility, emission of light, and for all processes of fusion at a high temperature.

3. _The lower Oxidising Zone_ lies in the outer border of the fusing zone at γ, and is especially suitable for the oxidation of oxides dissolved in vitreous fluxes.

4. _The upper Oxidising Flame_ at ε consists of the non-luminous tip of the flame. Its action is strongest when the air holes of the lamp are fully open. It is used for the roasting away of volatile products of oxidation, and generally for all processes of oxidation, when the highest temperature is not required.

5. _The lower Reducing Zone_ lies at δ, in the inner border of the fusing zone next to the dark cone. The reducing gases are here mixed with oxygen, and, therefore, do not possess their full power, hence they are without action on many substances which are deoxidised in the upper reducing flame. This part of the flame is especially suited for reduction on charcoal or in vitreous fluxes.

6. _The upper Reducing Flame_ lies at η, in the luminous tip of the dark inner cone, which, as already explained, may be produced by diminishing the supply of air. This part of the flame must not be allowed to get large enough to blacken a test tube filled with water and held in it. It contains no free oxygen, is rich in separated incandescent carbon, and therefore has a much stronger action than the lower reducing zone. It is used more particularly for the reduction of metals collected in the form of incrustations.

The subjoined is a drawing of the gauze burner, which is an open cylinder with wire gauze at the top.

When this is placed over the gas burner, a supply of air is drawn in at the bottom by the ascending current of gas, and the mixture burns above the gauze, with a very hot flame, quite free from smoke, the metallic meshes preventing the flame from passing down to the gas below. See ILLUMINATION, FUEL, FURNACE, GAS, LABORATORY, &c.

=Lamp, Flame′less.= _Syn._ GLOW LAMP. A coil of fine platinum wire is slipped over the wick of a spirit lamp, the greater part being raised above the cotton; the lamp is supplied with ether or alcohol, lighted for a moment and then blown out. The coil continues to glow in the mixed atmosphere of air and combustible vapour, until the liquid in the lamp is exhausted.

=Lamp, Monochromat′ic.= A lamp fed with a mixture of a solution of common salt and spirit of wine. It gives a yellow light, and makes every object illuminated by it appear either yellow or black. The human features are changed in a remarkable degree; the countenance appearing truly ghastly and unearthly.

=Lamp, Safety.= _Syn._ MINER’S LAMP, DAVY, GEORDY. The safety lamp of Sir H. Davy and George Stephenson are similar in principle, and were independently invented about the same time. That of Sir H. Davy consists of a common oil lamp, surmounted with a cylinder of wire gauze, the apertures of which are not greater than the 1/20th of an inch square, and the wire of which it is made to the 1/40th to the 1/60th of an inch in diameter. (See _engr._) The fire-damp (carbonetted hydrogen) along with air passes through the meshes into the interior of the gauze cylinder. Here it ignites, but the flame which is produced by its combustion cannot explode a mixture of fire-damp and air by which the lamp may be surrounded. The flame is prevented from passing to the exterior of the gauze by the cooling action of the metal of which it is constructed. When this lamp is taken into an explosive atmosphere, although the fire-damp may burn within the cage with such energy as sometimes to heat the metallic tissue to dull redness, the flame is not communicated to the mixture on the outside. These appearances are so remarkable, that the lamp becomes an admirable indicator of the state of the air in different parts of the mine, and if its admonitions are attended to, gives the miner time to withdraw before an explosion takes place.

=Lamp, Telescope.= This ingenious contrivance, invented by Messrs Murray and Heath, is intended for microscopic illumination. It consists of three brass tubes, sliding one within the other, the oil vessel being contained in the inner tube. The height of the lamp is regulated to the greatest nicety by simply turning one tube in the other, interior spiral guides preventing all chance of slipping. The great advantage of this arrangement is absence of the stand and bar usually employed for raising and lowering the lamp, which enables it to be used on all sides, and to be brought much closer to the microscope than other lamps. See _engr._, below.

=LAMP BLACK.= See BLACK PIGMENTS.

=LAMP′REY.= _Syn_. GREAT LAMPREY, SEAL. This fish is the _Petromizon marinus_ of Linnæus. It generally quits the sea in the spring, for the purpose of spawning, and remains in our rivers for a few months. Its flesh is soft and glutinous, and though esteemed a delicacy, is extremely difficult of digestion, if not otherwise unwholesome. Potted lampreys are usually so highly seasoned as to become a dangerous article of food. Henry I is said to have lost his life from the effects of a surfeit of lampreys.

=LAUDANINE.= C_{20}H_{25}NO_{3}. An alkaloid obtained by Hesse from the aqueous extract of opium. It is homologous with morphine and codeine. It dissolves in strong sulphuric acid with a rose-red colour, in strong nitric acid with an orange red colour, and in ferric chloride with emerald green colour.

=LANTHA′NIUM.= La_{92}. A rare metal, discovered by Mosander, associated with oxide of cerium. Oxide of lanthanium is a pale salmon-coloured powder, unaffected by ignition in open vessels. According to Zschiesche the atomic weight of lanthanium is 90·18. See CERIUM.

=LANTHOPINE.= C_{23}H_{25}NO_{4}. A base obtained by Hesse in small quantity, associated with other bases from the aqueous extract of opium. It is homologous with papaverine. Strong nitric acid dissolves it, giving rise to an orange red colour. Strong sulphuric acid gives with it a faint violet colour.

=LA′PIS.= [L.] A stone. The term was much employed by the old chemists, and is still commonly applied to several preparations used in medicine.

=Lapis Causticus.= See POTASSIUM.

=Lapis Divi′nus.= _Syn._ DIVINE STONE; LAPIS OPHTHALMICUS, L.; PIERRE DIVINE, Fr. _Prep._ 1. (Beer.) Verdigris, nitre, and alum, equal parts, melted together.

2. (P. Cod.) Alum, nitre, and blue vitriol, of each 3 oz.; camphor, 1 dr.; as last.

3. (Woolfuss.) Blue vitriol, nitre, alum, and camphor, equal parts, melted together, adding the camphor last. Astringent and detergent. 1 oz., dissolved in water, 1 pint, formed a once celebrated lotion. 1 dr. in water, 1 pint, is still used as a collyrium.

=Lapis Inferna′lis.= See NITRATE OF SILVER.

=Lapis Lazu′li.= See ULTRAMARINE.

=Lapis Lydius.= _Syn._ LYDIAN STONE. A siliceous slate, used as a touchstone by jewellers.

=Lapis Medicamento′sus.= _Syn._ MEDICINAL STONE; LAPIS MIRABILIS, L. _Prep._ (Ph. L. 1746.) Alum, litharge, and Armenian bole, of each 6 oz.; colcothar of green vitriol, 3 oz.; vinegar, 4 fl. oz.; mix, and evaporate to dryness. Formerly used to make an astringent and detergent lotion:——1 oz. to water, 1 pint. Once a popular application to ulcers, and in other cases; now disused.

=Lapis Vulnerar′ius.= Very similar to LAPIS DIVINUS.

=LARCH BARK.= The inner bark of the _Larix Europœa_, the common larch, has been lately introduced, under the form of a tincture, into the British Pharmacopœia.

Dr Stenhouse obtained from the bark a peculiar volatile constituent, possessed of acid properties for which the name of lariximic acid has been proposed. The other trees of the pine family are deficient in this acid. The young bark abounds most in it. Gum, starch, resin, and that variety of tannic acid, which forms olive green precipitates with the salts of iron, have also been found, in addition to other substances, in larch bark.

The inner bark, employed internally, has a special action on the mucous membranes, and acts as an astringent and mild stimulant. It is said to have been given with excellent results in hæmoptysis, as well as in bronchitis attended with copious expectoration, and in diseases of the urinary passages. Externally has been found serviceable in psoriasis, chronic eczema, and some other skin diseases. It is best to combine its extract or tincture with glycerin when it is to be used outwardly. See TINCTURE OF LARCH BARK.

=LARD.= _Syn._ HOG’S LARD, AXUNGE; ADEPS (Ph. L.), AXUNGIA (Ph. E.), A. SUILLUS (Ph. D.), A. PORCI, A. PRÆPARATUS (B. P.), L. The fat of the pig (_Sus scrofa_——Linn.) melted by a gentle heat, and strained through flannel or a hair sieve. The fat about the loins yields the whitest and hardest lard. “That which has been cured with chloride of sodium is not to be employed.” (Ph. L.) “It is not to be used without being first carefully washed with water.” (Ph. L. 1866.) Used chiefly to make ointments, and in cookery. See ADEPS.

=LARD′ING.= By many this is regarded as belonging to the higher style of cookery only, and too troublesome and extravagant to be adapted to the kitchens of the middle classes and the poor. This, we are assured, is not the case. On the contrary, “it is an economical process, and will make lean meat go much farther than without it.” The process of larding is as follows:——“Get what is called a larding needle, that is, a piece of steel from 6 to 9 inches long, pointed at one end, and having four slits at the other to hold a small strip of bacon when put between them. It will, perhaps, cost tenpence. Cut the bacon into pieces 2 or 3 inches long, and 1/4 to 1/2 an inch square; put each one after the other in the pin, insert it in the meat, and leave only about half an inch out; using 8 pieces to each pound.” (Soyer.)

=LARK.= The _Alauda arvensis_ (SKYLARK) and the _Alauda cristata_ (FIELD-LARK), with several other species of the same genus, form a light and nutritious article of food, by many esteemed a delicacy. The last, according to Galen and Dioscorides, eaten either roasted or boiled, ‘helps the colic.’ The heart, applied to the thigh, was also regarded to possess the same virtue.

=LARYNGITIS.= Inflammation of the larynx, or upper part of the windpipe. The symptoms that indicate this most dangerous malady are sore throat, accompanied with considerable pain in front of the throat, difficulty in breathing and swallowing, considerable hoarseness, change or loss of voice, a sense of suffocation, fever, restlessness, flushing of the face, and an eager desire for fresh air. We have described the accompaniments of this dread disease, in order that any one seized with an attack may know its nature, and at once send for his medical attendant. Should circumstances prevent his doing so immediately, as many leeches as possible should be applied to the centre of the throat.

=LAUD′ANUM.= This name is now understood to denote, exclusively, the common tincture of opium of the Pharmacopœia; but formerly the term was applied to several preparations of opium differing greatly from each other, both in their strength and mode of preparation. (See _below_.)

=Laudanum, Dutchman’s.= From the flowers of bull’s hoof or Dutchman’s laudanum (_Passiflora merucuja_——Linn.) infused in rum. Narcotic. Used as a substitute for tincture of opium in the West Indies.

=Laudanum, Ford’s.= This is merely the common tincture of opium aromatised with a little cloves and cinnamon.

=Laudanum, Houlton’s.= _Prep_. From opium 2-1/2 oz.; distilled vinegar, 1-1/2 pint; digested together for a week, the filtered tincture gently evaporated nearly to dryness, and then redissolved in weak spirit (1 of rectified spirit to 7 of water), 1 quart.——_Dose_, 10 to 60 drops.

=Laudanum, Neumann’s.= A fermented infusion of opium evaporated to the consistence of honey.

=Laudanum, Quince.= _Syn_. EXTRACTUM OPII CYDONIATUM, LAUDANUM CYDONIATUM, L. _Prep_. 1. Extract of opium made with quince juice; a few drops of the oils of cinnamon, cloves, and mace being added before the mass cools. Now seldom used.

2. LAUDANUM, LIQUID-QUINCE; (LAUDANUM LIQUIDUM CYDONIATUM, L.) (L. C. PARATUM FERMENTATIONE, L.) A fermented infusion of opium prepared with quince juice, aromatised with cloves, cinnamon, aloes wood, and yellow sandal wood, and evaporated so as to possess about twice the strength of the ordinary tincture. Now obsolete.

=Laudanum, Rousseau’s.= Wine of opium prepared by fermentation. See WINE.

=Laudanum, Smith’s Concentrated.= Resembles Battley’s LIQUOR OPII SEDATIVUS, but possesses about 6 times its strength.

=Laudanum, Swediaur’s.= _Prep_. From extract of opium, 2 parts, dissolved in a mixture of alcohol, 1 part, distilled water, 8 parts. Every 5 drops contain 1 gr. of opium.

=Laudanum, Sydenham’s Liquid.= _Syn_. LAUDANUM LIQUIDUM SYDENHAMI, L. Similar to WINE OF OPIUM——Ph. L., but rather stronger, and aromatised with a little cloves and cinnamon. Wine of opium is now always sold for it.

=Laudanum, Tartarised.= _Syn._ LAUDANUM LIQUIDUM TARTARIZATUM, L. A tincture of opium prepared with spirit alkalised with salt of tartar, and flavoured with aromatics. Obsolete.

=LAUGH′ING GAS.= See NITROUS OXIDE.

=LAUR′EL.= See CHERRY LAUREL, SWEET BAY, OIL, &c.

=LA′VA.= The matter thrown out by volcanoes. The beautiful ornamental vases, jugs, and other objects sold under the name, are a superior sort of unglazed coloured porcelain.

=LAVE′MENT.= See ENEMA.

=LAV′ENDER.= The flowers or flowering tops of _Lavandula vera_ or common garden lavender. An essential oil, spirit, and tincture, prepared from it, are officinal in the Pharmacopœias.

=Lavender Dye= (for COTTON). For 100 yards of material. Take 1 lb. of logwood, and 2 lbs. of sumach, and scald them separately. Then decant them into a proper sized tub, let them cool to 150° Fahr., and add 2 gills of vitriol. Winch the goods in this 20 minutes; lift, and run them slightly through acetate of iron; wash them in two waters; then give 1 lb. of logwood as before, raise with a pint of chloride of tin, wash in two waters; then in a tub of cold water put 4 oz. extract of indigo, enter and winch in this 15 minutes, lift; give one water, and dry.

=Lavender Dye= (for WOOL). Boil 5-1/2 lbs. of logwood with 2 lbs. of alum. Then add 10 oz. of extract of indigo. When cold put in the goods, and gradually raise to the boiling point. For 50 lbs.

=Lavender, Red.= See TINCTURE.

=Lavender, Smith’s British.= _Prep._ From English oil of lavender, 2 oz.; essence of ambergris, 1 oz.; eau de Cologne, 1 pint; rectified spirit, 1 quart. Very fragrant. See WATER (Lavender).

=Lavender, to Dye Silk.= (Mustpratt.) Into a vessel with warm water, as hot as the hand can bear, dissolve a little white soap, enough to raise a lather; then add one gill of archil liquor, and work the goods in this for fifteen minutes; ring out and dry.

Boil one ounce of cudbear, and add the solution to the soap and water instead of archil, which will give a lavender having a redder tint than with the archil. If a still redder shade of lavender be required the soap may be dispensed with.

=Lavender Water.= See SPIRITS, PERFUMED.

=LAX′ATIVES.= _Syn._ LENITIVES; LAXATIVA, LAXANTIA, LENITIVA, L. Mild purgatives or cathartics. The principal of these are——almond oil, cassia pulp, castor oil, confection of senna, cream of tartar, figs, grapes, honey, phosphate of soda, prunes, salad oil, tamarinds, &c.

=LAY′ERS.= Among gardeners, a mode of propagating plants, by laying down the shoots of young twigs, and covering a portion of them with the soil, without detaching them from the parent plant. To facilitate the rooting of such layers, the part beneath the soil is fractured by twisting or bruising it, or it is partly cut through with a sharp knife, immediately under a bud. When the layer has taken root, it is divided from the parent stem, and transplanted or potted. In this way, with a little care, nearly all plants may be multiplied.

=LEAD.= Pb. Eq. 207. _Syn._ PLUMBUM. This metal, like gold, silver, and iron, appears to have been known in the most remote ages of antiquity. The ore from which it is almost exclusively extracted, as being the only one found in abundance, is the native sulphide or sulphuret of lead, called by mineralogists galena.

_Prep._ On the large scale lead is obtained by roasting galena in a reverberatory furnace, and smelting the residue along with coal and lime. The lead thus obtained generally contains small quantities of both silver and gold, which it often pays to extract, by a method termed ‘Pattinson’s process.’ This process is founded on the circumstance that, when melted, lead containing silver is allowed to cool. The lead crystallises out first, leaving an alloy of lead and silver still fused. By removing the crystals of lead, as formed, until about four fifths are removed, the residue is an alloy of lead and silver much richer than the original. Repeated several times, this yields a rich alloy of silver and lead that is expelled and the silver obtained.

Another method for the removal of silver from lead is one employed in Glasgow, and known as the ‘Flack-Guillim’ process. It is thus described in ‘Dingler’s Polytechnic Journal,’ ccxxxv, 67-70, and in ‘Engineering’ for September 15th, 1876. “Eighteen tons of rich lead are melted, and one per cent. of zinc added. The molten mass then allowed to cool, the crust which forms is removed, and the lead sweated out in a small pot. The lead in the large pot is then treated with another half per cent. of zinc in the same way. A third addition of a quarter per cent. of zinc suffices to remove the greater part of the remaining silver, 5 dwts. being left in the lead per ton. This lead is then run into the improving pan, and the last traces of zinc oxidised out.”

Pure lead for chemical purposes may be obtained as follows, although the lead of commerce is nearly pure:

By reducing nitrate of lead with charcoal.

By heating the oxide left by igniting pure acetate of lead with black flux.

_Prop., &c._ The general properties of lead are too well known to require notice here. The sp. gr. of that of commerce is about 11·35; but in a state of absolute purity its greatest density is 11·45. It melts at about 600° Fahr., and when very slowly cooled, crystallises in octahedrons. At a white heat it boils, and is volatilised. When exposed to moist air, it soon becomes covered with a grey film. It is scarcely acted on by hydrochloric or sulphuric acids, although after some time both coat it with a film of chloride or sulphate. It is rapidly acted on by nitric acid, with formation of the nitrate. Pure water put into a leaden vessel and exposed to the air soon corrodes it, and dissolves the newly formed oxide; but river and spring water have little action upon lead, provided there is no free carbonic acid present, the carbonates and sulphates in such water destroying their solvent powers. It has been found that a very small amount of phosphate of sodium or of iodide of potassium, dissolved in distilled water, prevents its corrosive action on this metal. The lead in contact with such water gradually becomes covered with a superficial film of an insoluble salt of lead, which adheres tenaciously, and prevents further change. From this it appears that ordinary water (‘hard water’), which abounds in mineral salts, may be more or less safely kept in leaden cisterns; but distilled water and rain water, and all other varieties that contain scarcely any saline matter, speedily corrode, and dissolve a portion of lead, when kept in vessels of that metal. When, however, leaden cisterns have iron or zinc fastenings or braces, a galvanic action is set up, the preservative power of saline matter ceases, and the water speedily becomes contaminated with lead, and unfit for consumption as a beverage. Water containing carbonic anhydride also acts on lead, and this is the reason why the water of some springs (although loaded with saline matter), when kept in leaden cisterns, or raised by leaden pumps, possesses unwholesome properties.

M. Fordos, in a communication to the ‘Journal de Pharmacie et de Chimie,’ xix, 20, states that in the course of some experiments on the applicability of lead for water pipes and cisterns he could not detect a trace of lead in ten litres of river water taken from the leaden cistern of one of the Paris hospitals. But upon shaking pure water with shot and air, a coating of carbonate of lead was formed on the sides of the bottle, which almost rendered the glass opaque. On dissolving the film in nitric acid, and estimating the lead, it was found that one litre of water had produced five milligrammes of the carbonate. Wine and vinegar would also dissolve that film; and as shot is commonly used for cleaning wine bottles, lead frequently finds its way into wines, a fact which may account for many of the cases of chronic poisoning by lead which occur in large towns. The detection of small quantities of lead in forensic investigation would afford, therefore, no proof of any intentional poisoning.

Orfila’s erroneous statement that lead is a normal constituent of the human organism may also be accounted for in this way.

Free carbonic acid is evolved during the fermentation or decay of vegetable matter, and hence the absolute necessity of preventing the leaves of trees falling into water-cisterns formed of lead. The ‘eau de rose’ and the ‘eau d’orange’ of commerce, which are pure distilled water holding in solution small quantities of essential oil, and are imported in leaden canisters, always contain a small quantity of lead, and deposit a sediment, which is not the case when they are kept in glass or incorrodible vessels.

Lead and all its preparations are highly poisonous; and whether imbibed in almost infinitesimal quantities with our daily beverages and food, or swallowed in larger and appreciable doses, is productive of the most disastrous consequences, the real cause being unfortunately seldom suspected.

Mr G. Bischof[13] writes:——Some eight months ago a tube was passed in my laboratory, which is supplied with water by the New River Company, into the slate cistern so as to act as a syphon to supply some apparatus with water. The external surface of the tube inside the cistern was therefore alternately exposed to the action of air and water, according to the level of water in the cistern.

[Footnote 13: ‘Journal of the Chemical Society,’ April, 1867.]

Recently I noticed a white efflorescence on the greater part of the tube inside the cistern. An adjoining cistern of sheet lead, with a lead overflow pipe fixed into the bottom, shows nowhere any such corrosion.

On cutting the tube it became evident that it is a composition tube, that is to say, a lead tube, containing some antimony. On analysis it was found to be composed of——

Lead 98·3 Antimony 1·7 ———— 100·0

Although the external diameter of the tube is only half an inch, 0·29 gram of efflorescence was obtained per foot by gentle rubbing. This dried at 100° C. contained 1·02 per cent. of sulphuric acid, corresponding with 4·1 per cent. of sulphate of lead. The remainder, except 1·13 per cent. of a residue insoluble in nitric acid, is carbonate of lead.

The alternate exposure to air and water appears not essential to the corrosion, as I have observed a similar effect when the same tubing remained constantly under water. The interior of the tube has also been corroded, although of course no permanent efflorescence could be formed, owing to the rapid flow of the water.

The frequent practice of plumbers of using composition tubing in connection with water supplies is therefore highly reprehensible, being fraught with considerable danger to the health of those using the water for drinking or cooking.

Mr Louis Siebold detected lead in eight out of ten samples of concentrated solution of acetate of ammonia as well as in a sample of the ordinary solution of the British Pharmacopœia. In pursuing his investigations Mr Siebold found that solutions of acetate of ammonium are capable of dissolving lead from glass. He therefore advises that all forms of the solution, more particularly the concentrated liquor employed by many chemists for making the weaker solutions, should be kept in bottles free from lead.

With the acids lead or its oxides form salts, usually white in colour, and in the majority nearly insoluble in water, but readily soluble in acids.

_Tests._ The oxides and salts of lead, mixed with a little carbonate of soda, and exposed on a charcoal support to the reducing flame of the blowpipe, readily yield a soft and ductile globule of metallic lead, and the charcoal, at the same time, becomes covered with a yellowish incrustation of oxide of lead. Both metallic lead and its oxides are soluble in nitric acid, furnishing a solution which may be examined with ease.

Solution of lead salts may be recognised by the following reactions:——Sulphuretted hydrogen, sulphydrate of ammonium, and the alkaline sulphides, give black precipitates, insoluble in the cold dilute acids, alkalies, alkaline sulphides, and cyanide of potassium. Potassium and sodium hydrates give a white precipitate, soluble in excess. Ammonia (except with the acetate) gives a white precipitate, insoluble in excess. The carbonates of potassium, sodium, and ammonium, give a white precipitate, insoluble in excess. Dilute sulphuric acid (in excess), and solutions of the sulphates give a white precipitate, sparingly soluble in dilute acids, but soluble in a hot boiling solution of potassium carbonate. Chromate and bichromate of potassium give yellow precipitates insoluble in dilute nitric acid, and soluble in solution of potassium hydrate. Iodide of potassium gives a yellow precipitate, soluble in great excess by heat, and separating in small, brilliant, golden-yellow scales, as the liquid cools. A piece of polished zinc precipitates metallic lead in an arborescent form, hence called the lead tree. To prepare for these tests, a solid supposed to contain lead should be digested in nitric acid, when the solution, evaporated to dryness and redissolved in water, may be tested as above.

_Estim._ This has been already referred to under previous heads. The ores of lead (galena) may be digested in nitric acid, when the solution may be treated with sulphuric acid, and the lead estimated from the weight of the precipitated sulphate. This is called an assay in the wet way. The method adopted by practical mineralogists is an assay in the dry way, and is conducted as follows:——A small but powerful air-furnace, charged with coke, is brought to as high a temperature as possible, and a conical wrought-iron crucible plunged into the midst of it; as soon as the crucible has attained a dull-red heat, 1000 gr. of the galena, reduced to powder, are thrown into it, and stirred gently with a long piece of stiff iron wire flattened at the one end, in order to expose as large a surface of the powdered ore to the air as possible, observing now and then to withdraw the wire, to prevent it becoming red hot, in which case some of the ore would permanently adhere to it, and be reduced before the intended time; the roasting is completed in 3 or 4 minutes, and any portion of the ore adhering to the stirrer being detached by a knife, and returned into the crucible, the latter is covered up, and allowed to attain a full cherry-red heat, when about 2 or 3 spoonfuls of reducing flux are added, and the whole brought to a full white heat; in 12 to 15 minutes, the portion of metal and scoria adhering to the sides of the crucible are scraped down into the melted mass with a small stick of moist green wood, after which the crucible is again covered, and the heat urged for 2 or 3 minutes longer, so as to keep the mass in a perfectly liquid state during the whole time; the crucible is then removed from the fire with the crucible-tongs, and adroitly tilted so as to discharge its contents into a small, ingot-mould of brass, observing to rake the scoria from the surface to the sides of the crucible, so as to allow the molten lead to be poured out without it; the scoria is then reheated in the crucible with about 1/2 spoonful of flux, and after being cleansed with a piece of green wood, as before, is at once poured into a second mould, which is instantly inverted; the little button of lead thus obtained is added to the lead in the other mould, and the whole is accurately weighed. The weight, divided by 10, gives the per-centage of lead (including silver, if present) in the ore examined.

One half of the lead thus obtained is put into a dry cupel of bone ash, and placed in the cupelling furnace, and treated as described in the article on assaying; the metallic button left on the cupel is then detached and weighed. The weight, divided by 5, gives the per-centage of pure silver.

_Obs._ The flux commonly employed in the above assay is composed of red argol, 6 parts; nitre, 4 parts; borax, 2 parts; fluor spar, 1 part; well pulverised and thoroughly mixed together. When the ore is very refractory, about a spoonful of carbonate of potassium should be added for each 1000 grains of ore, in which case the roasting may be dispensed with. The quantity of silver in argentiferous galena varies from 3/10000 to 1/3 part of the whole. Whenever this ore contains above 2 parts of silver in the 1000, it is found to be profitable to extract the latter. Indeed, by Pattison’s process it is found that as small a proportion as 1 in 8000 can be extracted with profit.

_Uses._ The uses of lead in the arts are well known. It enters into the composition of many important alloys (pewter, type-metal, shot-metal, solder, &c.), it furnishes us with several valuable pigments (chrome yellow, &c.), and it is extensively used in dyeing. Some of its preparations are employed in medicine.

_Ant., &c._ Administer an emetic of sulphate of zinc or sulphate of copper, and, if necessary, tickle the fauces with the finger or a feather, to induce vomiting. Should this not succeed the stomach-pump may be had recourse to. Epsom or Glauber’s salts, or alum, dissolved in water, or water acidulated with sulphuric acid, followed by tea, water gruel, or barley water, are the proper antidotes, and should be taken as soon after the poison has been swallowed as possible. In poisoning by white lead, Dr Alfred Taylor recommends the administration of a mixture of sulphate of magnesium and vinegar, as preferable to the sulphate alone. When the symptoms are those of painter’s colic, the treatment recommended under that head should be adopted. In paralysis arising from lead, small doses of strychnine and its preparations may be cautiously administered. A symptom of poisoning by lead is the formation of a narrow leaden blue line, from 1/20th to 1/6th of an inch wide, bordering the edges of the gums, attached to the neck of two or more teeth of either jaw. (Dr Burton.) This discoloration may often be detected or rendered more conspicuous by rinsing the mouth out with water holding a little sulphuretted hydrogen or sulphydrate of ammonium in solution. Chevallier and Rayer recommend the use of sulphurous or hepatic mineral waters, or of artificial solutions of sulphuretted hydrogen or alkaline sulphides in water, both in cases of acute and chronic poisoning by lead; but the practical success of this plan does not appear to have been in proportion to theoretical anticipations. The moist and freshly precipitated sulphides of iron are said by their advocates to be infallible if taken sufficiently early.

=Lead in Aerated Water.= Some time since Sir Robert Christison condemned the use of syphons for lemonade, owing to the action of free tartaric acid upon lead, and the rapidity with which waters containing any free acid become charged with lead in syphons. According to Professor Miller, 0·0175 gr. of lead per gallon is not an unusual amount for average cistern water. Mr John S. Thompson, however, reports to the Edinburgh University Chemical Society that, after such water has been aerated and put into a syphon, the amount of lead dissolved in it begins to rise in a rapid manner. Thus in potash water, drawn from a syphon, 0·0408 grain of lead per gallon was found to be present, being nearly 25 times the quantity found in the same water before it entered the syphon. Pure aerated water again drawn in a similar manner from a syphon gave 0·0816 gr. of lead per gallon, or exactly double the amount found in the potash water, showing at once the well-known protective action that salts of the alkalies and alkaline earths have on lead. “Although,” says the ‘Medical Journal,’ “these results are sufficiently high and alarming; still, when the water is drawn off in small quantities at a time, as is frequently the case with invalids, the results are found to be still higher; thus, when potash water was so treated, 0·0455 gr. of lead per gallon was found, while aerated water, drawn off in small quantities, gave 0·0933 gr. of lead per gallon, showing a very marked rise in both cases. The cause of this increase in quantity of the lead appears to be owing, not so much to the lengthened period of contact between the liquid and the metal as to the fact that the nozzle of the syphon, being exposed to the atmosphere in a moist state, becomes rapidly oxidised or carbonated, and is left in the most suitable condition for entering into solution, so that, when merely small portions of the liquid are drawn off each time, a comparatively concentrated solution of lead is obtained. These results,” continues the same authority, “compare accurately with those which were obtained by Messrs Savory and Moore, in examining the contents of a series of syphons of aerated water for Dr George Owen Rees, F.R.S., whose attention was drawn to the subject by detecting symptoms of lead-poisoning in himself after he had been in the habit for some time of drinking such aerated water.”

=Lead, Acetate of.= Pb(C_{2}H_{3}O_{2})_{2}. _Syn._ PLUMBIC ACETATE, SUGAR OF LEAD, PLUMBI ACETAS. (B. P.) _Prep._ Litharge (in fine powder) 24; acetic acid, 40; distilled water, 20; mix the acetic acid and the water, add the litharge, and dissolve with the aid of a gentle heat, filter, evaporate until a pellicle forms, and crystallise. Drain and dry the crystal.

Acetic acid (sp. gr. 1·0843), 23 parts, is gently heated in a copper boiler rendered electro-negative by means of a large flat piece of lead soldered within it, and litharge (pure, and in fine powder), 13 parts, is sprinkled in; the heat is then continued, with constant stirring, until the acid is saturated, when the mother-waters of a former process, if any, are added, and the whole is heated to the boiling point, and allowed to settle until cold; the clear portion is now decanted, and evaporated in a similar vessel until the liquor has the sp. gr. 1·266 or 1·267, when it is run into salt-glazed stone-ware vessels (the edges of which have been well smeared with candle grease), and allowed to crystallise. The product is 38 to 38-1/2 parts of crystallised sugar of lead. It is found to be advantageous to preserve a very slight excess of acid during the boiling and crystallisation, to prevent the formation of any basic acetate the presence of which impedes the formation of regular crystals.

From litharge, 112 lbs.; acetic acid (sp. gr. 1·057), 128 lbs. _Prop._ 180 to 184 lbs.

_Prop._ Pure acetate of lead forms colourless, transparent, prismatic crystals, slightly efflorescent in dry air; it is soluble in 8 parts of alcohol and in 1-1/4 part of cold water; the aqueous solution has a sweet astringent taste, and feebly reddens litmus, but turns turmeric and the juice of violets green; when gently heated, it melts in its water of crystallisation; by continuing the heat, the whole of the water is expelled, and the dry acetate obtained; at a higher temperature the salt suffers decomposition, and acetic acid, acetone, &c., is given off. Commercial acetate of lead is in general a confused crystalline mass, somewhat resembling broken lump sugar. It is powerfully astringent and poisonous.

When pure it is completely soluble in distilled water acidulated with acetic acid forming a transparent colourless solution, “38 grains dissolved in water require for complete precipitation 200 grains measures of the volumetric solution of oxalic acid.” (B. P.)

_Uses, &c._ Acetate of lead is extensively employed in dyeing and calico-printing. In _medicine_ it is used as an astringent, styptic, and hæmostatic; in pulmonary, uterine, and intestinal hæmorrhage, colliquative diarrhœa, phthisical sweats, &c. It is usually combined with morphia or opium, and with acetic acid to prevent it passing into the state of the poisonous carbonate in the stomach.——_Dose_, 1/2 gr. to 2 gr. (Collier); 1 to 2 gr. to 8 or 10 gr., twice or thrice a day (Pereira); 3 gr. to 10 gr., every 6 or 8 hours (A. T. Thomson). _Externally_, as a collyrium, 10 gr. to water, 8 fl. oz. (A. T. Thomson); as a lotion, 20 gr. (A. T. Thomson), 1 dr. (Collier) to water, 8 or 10 fl. oz.; as an injection, 40 gr. to rose water, 1/2 pint. The lotion is cooling and sedative, and is commonly used in excoriations, local inflammations, &c.

=Basic Acetates.= There are several of these salts, but only one is of any importance.

=Tribasic Lead Acetate or Double Plumbic Acetate, and Dioxide.= Pb(C_{2}H_{3}O_{2})_{2} 2PbO. _Syn._ SUBACETATE OF LEAD; BASIC LEAD CITRATE; GOULARD’S ACETATE OF LEAD; PLUMBI SUBACETAS (B. P.). _Prep._ Litharge, 7; acetate of lead, 10; and distilled water, 40; are boiled half an hour, and evaporated down, and allowed to crystallise out of contact with air.

Used under the form of “Plumbi subacetas liquor” v. (B. P.)

=Lead, Arse′′niate of.= Pb_{3}(AsO_{4})_{2}. _Syn._ ARSENATE OF L.; PLUMBI ARSENIAS, L. _Prep._ Gradually add a solution of acetate of lead to another of arseniate of sodium. A white, insoluble powder. Proposed as an external application in certain forms of cancer.

=Lead, Bro′mide of.= PbBr_{2}. _Syn._ PLUMBI BROMIDUM, L. _Prep._ By precipitating a solution of neutral acetate or nitrate of lead with a solution of bromide of potassium. A white, crystalline powder, sparingly soluble in water. It fuses by heat into a red liquid, which turns yellow when cold. It has been used in the same cases as iodide of lead.

=Lead, Car′bonate of.= PbCO_{3}. _Syn._ PLUMBI CARBONAS, L. _Prep._ By precipitating a cold solution of either acetate or nitrate of lead with a solution of an alkaline carbonate, observing to well wash the precipitate and dry it in the shade. This preparation is seldom employed, the commercial carbonate (WHITE LEAD) being substituted for it. See WHITE PIGMENTS.

=Lead, Chloride of.= PbCl_{2}. _Syn._ CHLORIDE LEAD; PLUMBI CHLORIDUM (Ph. L. 1836). _Prep._ (Ph. L. 1836). Dissolve acetate of lead, 19 oz., in boiling water, 3 pints; next dissolve chloride of sodium, 6 oz., in boiling water, 1 pint; mix the two solutions, and when cold wash and dry the precipitate. A white, crystalline powder.

Dissolve finely powdered litharge in boiling dilute hydrochloric acid, and set aside the filtered solution to cool. Brilliant colourless needles.

_Prop._ Soluble in 135 parts of cold and in 22 parts of boiling water; it melts when heated, and solidifies on cooling, forming a horn-like substance (horn lead; plumbi corneum).

_Uses, &c._ In the Ph. L. 1836, chloride of lead was ordered to be employed in the preparation of ‘hydrochlorate of morphia.’ Mr Tuson highly recommends it in cancerous affections, to allay pain and restrain morbid action, either in the form of a lotion or ointment.

Various mixtures of lead chlorides and oxide are employed as a white pigment under the name of ‘Pattison’s white.’ It is prepared by rapidly mixing a boiling solution of lead chloride with an equal volume of lime water. Another similar compound is called ‘patent yellow’ or ‘Turner’s yellow.’

=Lead, Chromate of.= PbCrO_{4}. _Syn._ LEMON YELLOW, LEIPSIG YELLOW, PARIS YELLOW. _Prep._ By adding a filtered solution of acetate or nitrate of lead to a like solution of chromate of potassium, as long as the precipitate forms, which is collected, washed with water, and dried. For information respecting the manufacture of this substance on the large scale, as a colouring substance (chrome yellow), see YELLOW PIGMENTS.

=Lead, Dichromate of.= _Syn._ CHROME ORANGE, CHROME RED. PbCrO_{4}.PbO. _Prep._ By adding to a solution of nitrate or acetate of lead a solution of chromate of potassium, to which an equivalent of potassa has been added. This compound is of a splendid scarlet colour. See RED PIGMENTS.

=Lead, Cy′anide of.= PbCy_{2}. _Syn._ PLUMBI CYANIDUM, L. _Prep._ By adding hydrocyanic acid to a solution of acetate of lead, as long as a precipitate forms, which, after being washed with distilled water, is dried by a very gentle heat, and preserved from the light and air. Sometimes used as a source of medicinal hydrocyanic acid.

=Lead, Iodide of.= PbI_{2}. _Syn._ LEAD IODIDE; PLUMBI IODIDUM (B. P., Ph. L. E. D.). _Prep._ (B. P.) Nitrate of lead, 4; iodide of potassium, 4; distilled water, a sufficiency. Dissolve with the aid of heat the nitrate of lead in 30 of water, and the iodide of potassium in 10 of water, mix, collect the precipitate, wash, and dry at a gentle heat.

_Prop., &c._ A rich yellow-coloured powder, soluble in acetic acid, alcohol, and boiling water; when heated, it fuses and volatilises in yellow vapour, but with a higher degree of heat, violet vapours of iodine are evolved, leaving a residuum (lead) which is wholly soluble in nitric acid.——_Dose_, 1/4 gr. to 4 gr. or more, made into a pill; as a deobstruent and resolvent, in enlargements of the cervical, axillary, and mesenteric glands, and in scrofulous affections and scirrhous tumours.

=Lead, Nitrate of.= Pb(NO_{3})_{2}. _Syn._ PLUMBI NITRAS, L. (B. P., Ph. E. D.)

_Prep._ (Ph. D.) Litharge (in fine powder), 1 oz.; pure nitric acid, 2 fl. oz., diluted with water, 1/2 pint; mix, apply a sand-heat, and evaporate to dryness, occasionally stirring; boil the residuum in water, 2-1/2 pints; filter, acidulate with a few drops of nitric acid, evaporate to a pellicle, and set the liquid aside to cool; lastly, dry the deposited crystals on bibulous paper, and preserve them in a well closed bottle.

(Commercial.) By dissolving white lead in dilute nitric acid, and crystallising.

_Uses, &c._ This salt is extensively used in calico printing, and in the preparation of the iodide and other salts of lead. It was formerly much esteemed in asthmas, hæmorrhages, and epilepsy. It is now often used in an external application in cancer, ulcers, wounds, and various cutaneous affections. It is the basis of Liebert’s celebrated ‘cosmétique infallible,’ and of Ledoyen’s ‘disinfecting fluid.’ A very weak solution is an excellent application to chapped nipples, lips, hands, &c.——_Dose_, 1/2 to 1 gr.; in the form of pill or solution, washed down with a tablespoonful of water very slightly acidulated with nitric acid.

=Lead, Nitro-sac′charate of.= _Syn._ PLUMBI NITROSACCHARAS, L. _Prep._ (Dr S. E. Hoskins.) Nitric acid, 1 part; water, 19 parts; mix; in this dilute acid saccharate of lead (in fine powder) is to be dissolved, and set aside that crystals may form, which are to be dried by pressure between the folds of bibulous paper. A weak solution of the salt, acidulated with saccharic acid, has been employed by Dr Hoskins as a solvent for phosphatic calculi, with apparent success.

=Lead, Oxide of.= PbO. _Syn._ MONOXIDE OF LEAD, PROTOXIDE OF LEAD, YELLOW OXIDE OF LEAD, PLUMBI OXYDUM (B. P.) _Prep._ This substance is obtained perfectly pure by expelling the acid from nitrate of lead, by exposing it to heat in a platinum crucible; or, still better, by adding ammonia to a cold solution of nitrate of lead until the liquid becomes faintly alkaline, washing the precipitate with cold water, drying it, and heating it to moderate redness for 1 hour.

_Prop., &c._ Pure protoxide of lead has a lemon-yellow colour, and is the best of all the salts of lead. It is very heavy, slightly soluble in water, and freely so in acids, particularly when in the hydrated state; the aqueous solution has an alkaline reaction; at a red heat it melts, and assumes a semi-crystalline form on cooling; in the melted state it rapidly attacks and dissolves siliceous matter, with which it unites to form glass (flint glass); when heated along with organic substances of any kind, it is easily reduced to the metallic state.

On the commercial scale, this oxide is prepared by heating the grey film or dross that forms on the surface of melted lead when freely exposed to the air. When the process is arrested, as soon as the oxide acquires a uniform yellow colour, it is called massicot; when the heat is still further increased, until it fuses or partially vitrifies, it forms litharge of which there are several varieties. See LITHARGE, MASSICOT.

=Lead, Red Oxide of.= _Syn._ RED LEAD, MINIUM. _Prep._ This is prepared by exposing unfused protoxide of lead to the air for a long time, at a dull red heat. It is a very heavy powder, of a fine red colour, decomposed by a strong heat into protoxide of lead, and oxygen gas, which is evolved. Somewhat uncertain in its composition, but is generally of the composition Pb_{3}O_{4} or PbO_{2}2PbO. See RED PIGMENT.

=Lead, Dioxide.= PbO_{2}. _Syn._ BINIODIDE OF LEAD, PEROXIDE OF LEAD, PUCE OXIDE OF LEAD. _Prep._ By digesting red oxide of lead in dilute nitric acid; or by infusing a mixture of protoxide of lead and chlorate of potassium at a heat a little below redness, and washing the powdered mass in water; or by transmitting a current of chlorine gas through a solution of neutral acetate of lead. This oxide gives up half its oxygen at a red heat; acids also decompose it. Its chief use is in chemical analysis, to separate sulphurous acid from certain gaseous mixtures, which it converts into sulphuric acid, which it at the same time absorbs, forming sulphate of lead. It has recently been employed as an oxidising agent in the manufacture of the ANILINE DYES.

=Lead, Pyrolig′nite of.= Sugar of lead made with rough pyroligneous acid. Used in dyeing, chiefly for the preparation of acetate of alumina.

=Lead, Sac′charate of.= _Syn._ PLUMBI SACCHARAS, L. _Prep._ (Dr S. E. Hoskins.) Nitric acid, 2 parts; water, 10 parts; mix in a porcelain capsule, add of sugar, 1 part; and apply heat until reaction ceases; then dilute the liquid with distilled water, neutralise it with powdered chalk, filter, and add to the filtrate a solution of acetate of lead, as long as a precipitate (saccharate of lead) forms; lastly, collect the precipitate on a filter, wash and dry it. Used to make nitro-saccharate of lead, and as a source of saccharic acid.

=Lead, Sul′phate of.= PbSO_{4}. _Syn._ PLUMBI SULPHAS, L. This salt occurs native in transparent octohedra (lead vitriol), and is obtained in large quantities as a by-product in the preparation of acetate of aluminum for dyeing.

_Prep._ By adding dilute sulphuric acid to a solution of a soluble salt of lead. It is very sparingly soluble in water and in dilute sulphuric acid, soluble in strong hydrochloric acid and bitartrate of ammonium.

=Lead, Sul′phide of.= PbS. _Syn._ PLUMBI SULPHIDE. This occurs abundantly in nature in the form of GALENA.

_Prep._ By fusing metallic lead with sulphur or by passing sulphuretted hydrogen through a solution of a salt of lead.

=Lead, Tan′nate of.= _Syn._ PLUMBI TANNAS, L. _Prep._ Precipitate a solution of acetate of lead with an infusion of galls, and wash and dry the precipitate. Astringent, sedative, and hæmostatic.——_Dose_, 1 gr. and upwards, made into a pill. It has been highly recommended in the form of ointment and cataplasms, in bed-sores, chronic ulcers of the feet, white swellings, &c.

=Lead, Tar′trate of.= _Syn._ PLUMBI TARTRAS, L. _Prep._ By precipitating acetate of lead, by tartrate of ammonium, washing and drying.

=LEAD DUST.= _Syn._ PULVIS PLUMBI, PLUMBUM DIVISUM, L. _Prep._ By melting new lead, adding bruised charcoal, mixing with violent agitation, which must be continued until the metal ‘sets,’ and then pounding and washing away the charcoal. Used by potters.

=LEAD, GRANULATED.= _Prep._ By melting new lead, and pouring it in a small stream from an iron ladle with a hole drilled in its bottom, into a pail of water. Used to make solutions and alloys.

=LEAD, RED.= See RED PIGMENTS.

=LEAD, WHITE.= See WHITE PIGMENT.

=LEAD PYROPH′ORUS.= See PYROPHORUS.

=LEATH′ER.= _Syn._ CORIUM, CORIUS, L. Leather is the skin of animals which has been prepared by one or other of several processes adopted for the purpose, having the common object of preventing its spontaneous destruction by putrefaction, besides other objects, which are more or less peculiar to each variety of this useful substance.

Leather is only prepared on the large scale, and primarily either by the process of ‘TANNING’ or ‘TAWING,’ in the manner briefly described under these heads.

CURRIED LEATHER is leather which has been tanned, and sold to the currier, who, after soaking it in water, and rubbing it to soften it, pares it even with a broad, sharp knife, rubs it with a piece of polished stone or wood, and, whilst still wet, besmears it with oil or grease (DUBBING), which gradually penetrates the leather as the moisture evaporates. It next undergoes the operation of ‘waxing,’ which consists of first rubbing it on the flesh side with a mixture of oil and lamp black; it is then ‘black-sized’ with a brush or sponge, and, when dry, is lastly ‘tallowed’ with a proper cloth, and ‘slicked’ upon the flesh side with a broad and polished lump of glass. Leather curried on the hair or grain side, termed ‘black on the grain,’ is blackened by wetting it with iron liquor, and rubbing it with an iron ‘slicker’ before applying the oil or grease. The grain is finally raised by the ‘pommel’ or ‘graining board’ passed over it in various directions.

Leather is dyed or stained by the application, with an ordinary brush, of any of the strong liquid dyes, in the cold or only gently heated, to the surface of the skin previously stretched on a board. The surface, when dry, is commonly finished off with white of egg and the pommel or smoothing stick. Bookbinders generally employ copperas water as a black stain or sprinkle; a solution of indigo as a blue one; and a solution of salt of tartar or common soda, as a brown one.

Leather, before being japanned or varnished, as in the preparation of what is called ‘ENAMELLED’ and ‘PATENT LEATHER,’ is carefully freed from grease by the application of absorbent substances or hard pressure between rollers, and the surface is nicely shaved, smoothed, and polished by appropriate tools, the varnish is then applied to the grain side for the former, and the flesh side of the skin for the latter, which is previously stretched out tight on a board to receive it. The whole is, lastly, submitted to a gentle stove-heat to harden the varnish; and the process is repeated, if necessary.

_Uses, &c._ These are well known, and are all but universal. The leather manufacture of Great Britain is equal in importance and utility to any other department of our industry, and inferior in point of value and extent only to those of cotton, wool, and iron. “If we look abroad on the instruments of husbandry, on the implements used in most of the mechanic trades, on the structure of a multitude of engines and machines; or if we contemplate at home the necessary parts of our clothing——breeches, shoes, boots, gloves——or the furniture of our houses, the books on our shelves, the harness of our horses, or even the substance of our carriages; what do we see but instances of human industry exerted upon leather? What an aptitude has this single material in a variety of circumstances for the relief of our necessities, and supplying conveniences in every state and stage of life! Without it, or even without it in the plenty we have it, to what difficulties should we be exposed?” (Dr Campbell.) Leather is a kind of natural felt, but of much closer and firmer texture than that of artificial origin. “The thinner and softer kinds of leather are sometimes used as body-clothing; but its special and proper purpose is the manufacture of coverings for the feet, to protect them from cold and water.” (Eras. Wilson.) See JAPANNING, VARNISH, &c.

=Leather, destruction of, by Gas.= It is well-known that the binding of books suffer considerable damage, when the books are kept in apartments lighted by coal gas. That the cause of this deterioration is due, as was believed, to the combustion of the bisulphide of carbon contained in the gas, and its consequent oxidation into sulphuric acid, is exemplified by the following interesting communication from Professor Church, published in the ‘Chemical News’ for October 19th, 1877. He says:——“Vellum seems unaffected; morocco suffers least; calf is much injured, and russia still more so. The disintegration is most rapid with books on the upper shelves of a library, whither the heated products of combustion ascend, and where they are absorbed and condensed.

By comparing specimens of old leather, with specimens of new, it is quite clear that the destructive influence of gas is due mainly to its sulphur.

True there are traces of sulphates in the dye and size of new leather bindings, but the quantity is insignificant and there is practically no free sulphuric acid. That leather may be destroyed by the oil of vitriol produced by the burning of gas in a library is proved by the following observations and analyses.

The librarian of one of our public libraries forwarded to me the backs of several volumes, which had been ‘shed’ by the books on the upper shelves in an apartment lighted by gas. The leather of one of these backs (a volume of the ‘Archæologia’) was carefully scraped off so as to avoid any paper or size from underneath. This task of scraping was easy enough, for the leather was reduced to the consistency of Scotch snuff. On analysis of the watery extract of this leather, the following figures were obtained:——

Free sulphuric acid in decayed leather 6·21 per cent. Combined 2·21 ” ———— 8·42

=LEAV′EN.= Dough which has become sour or run into a state of incipient putrefaction. When a small quantity of it is added to recent dough, it excites fermentation, but is apt to produce a disagreeable taste and odour in the bread. It is now superseded by yeast. Both these substances are used in the same way.

=LEAVES (Medicated).= _Syn._ FOLIA MEDICATA, L. On the Continent several preparations of this kind are in use. In many cases the leaves of tobacco deprived of nicotine, by soaking them in water, are dried, and then moistened or steeped in a tincture or infusion of the medicinal substance. In this way belladonna, camphor, and henbane, are often administered. Cruveilhier recommends opiated belladonna leaves for smoking in troublesome coughs, phthisis, spasmodic asthmas, &c., to be prepared as follows:——Belladonna leaves, 1 oz., are steeped in an infusion of opium, 10 gr., in water, 1 fl. oz. (or less), and are then carefully dried in the shade. “MUSTARD LEAVES (Riggollot’s) consist of mustard moistened with water, spread on paper, and dried.” (Squire.) See CIGARS (in _pharmacy_), and VEGETABLES.

=Leaves, How to Dissect.= “For the dissection of leaves,” says Mrs Cussons, “I find the process of maceration too long and tedious, to say nothing of the uncertainty as to the results. I have therefore adopted the use of alkali in saturated solution, the specimens to be introduced while the liquid is heated to the boiling point; the time of immersion to be regulated by the character of the various leaves and the nature of the epidermis to be removed. When the specimen is freed from epidermis and cellular tissue, it must be subjected to the action of chlorine to destroy the colouring matter. The introduction of peroxide of hydrogen not only serves to render the lace-like specimen purer in colour, but also preserves it. In destroying the colouring matter in ferns this also is invaluable; added to the chlorine it gives a solidity to the bleached fronds, and appears to equalise the action of the chlorine. For skeletonising capsules the slow process of maceration by steeping in rain-water is alone available; a moderate heat may be applied to hasten the process, but alkali is useless. The only known flower which can be dissected is the _Hydrangea japonica_. The fibrous nature of the petals renders it easy to skeletonise in the perfect truss in which it grows. Skeletonised leaves and capsules appear to gain in the process a toughness and durability not possessed by them in their natural state.”

=LECANOR′IC ACID.= See ORSELLINIC ACID.

=LEECH.= _Syn._ HIRUDO (B. P., Ph. L. & D.), L. The officinal leech of the Pharmacopœias is the _Sanguisuga medicinalis_ (_Hirudo medicinalis_——Cuv.), familiarly known as the ‘old English’ or ‘speckled leech.’ It is also occasionally called the ‘Hamburg grey’ or ‘Russian leech,’ from being imported from those parts. Its characteristics are——Back, greenish or olive green, sometimes almost black or intense brown, with 6 rusty-red or yellowish longitudinal stripes, which are mostly spotted with black.——Belly, dirty yellow or light olive green, spotted more or less with black. The spots are very variable in size and number; in some cases few, in others so numerous as to form the prevailing tint of the belly. This variety, which is the most valuable of the commercial leeches, is chiefly imported from Hamburg.

Another variety of leech, the _Sanguisuga officinalis_, familiarly known as the ‘Hamburg’ or ‘French green leech,’ is imported from Bordeaux, Lisbon, and Hamburg. Its characteristics are——Back, brownish olive-green, with 6 reddish or rusty yellow longitudinal bands.——Belly, light dirty pea-green, or yellowish green, free from spots, but exhibiting two lateral stripes. This leech is vastly inferior to the preceding variety, and some of those imported from France and Portugal are absolutely useless, from their indisposition to bite, arising from the fraud practised by the collectors and dealers of gorging them with blood to improve their appearance before sending them to market. The above are the species of leech commonly employed in medicine in this country, but many others are noticed by writers on the subject.

Leeches are best preserved in water obtained from a pond, and occasionally changed; when kept in spring water they soon die. The introduction of a hand to which an ill-flavoured medicine or odour adheres into the water in which they are kept is often sufficient to poison them. The application of saline matter to the skin of leeches, even in very small quantities, immediately occasions the expulsion of the contents of the stomach; hence a few grains of common salt are frequently sprinkled over them, to make them disgorge the blood which they have swallowed. The frequent changing of the water in which leeches are kept is injudicious. Once a month in winter, and once a week in summer, is deemed sufficiently often by the large dealers, unless the water becomes discoloured or bloody, when it should be changed every day, or every other day. When clean pond water cannot be obtained, clean rain water that has been well exposed to the air should alone be employed. Mr J. R. Kenworthy recommends placing in the water a few balls of irregular lumps of pure clay, about 2-1/2 inches in diameter; a method which we can recommend as both simple and successful. The plan adopted by M. Fée is as follows:——Place 7 inches of a mixture of moss, turf, and charcoal, in a marble or stone trough, over which sprinkle some small pebbles. At one end of the trough, and about half way up, place a thin shelf of stone or marble, pierced with small holes, on which put first some moss, or portions of marsh horse-tail (_Equisetum palustre_), and on this a layer of pebbles to keep it down; then pour in water sufficiently high just to moisten the moss and pebbles, put in the leeches, and tie over the mouth of the trough with a cloth. Another plan consists in keeping the leeches in a glass tank, or aquarium, provided with a pebbly bottom and a few healthy aquatic plants.

_Propag._ According to Dr Wagner, an annual feast on living blood is necessary to render leeches able to grow and propagate. These conditions can only be fulfilled by restoring to the breeding cisterns those which have been already employed. All artificial methods of feeding them by bladders or sponges of blood have been found to fail. He recommends the employment of two tanks, with the bottom formed of loam, clay, or turf, surrounded by an inner border of a similar substance, and an outer one of sand——the one for leeches fit for medical use——and the other for breeding, or for such leeches as have been applied. No leeches are to be taken from the breeding tank until a year has elapsed after their having been applied and fed with human blood; and their removal to the first tank should take place in September, or October, as by this time the breeding season is over. By this plan all leeches that have been applied are to be carefully restored to the breeding tank, without making them disgorge the blood they have swallowed.

=LEECH′ING.= This consists in the application of leeches to any vascular part of the body, for the purpose of withdrawing blood from it, and thus allaying local inflammation, distension of vessels, &c. Leeches are most conveniently applied by means of a common pill-box or a wine glass. The part should be previously washed perfectly clean, and if covered with hair should be closely shaved. Sometimes leeches are indisposed to bite; in such cases, allowing them to crawl over a piece of dry linen or calico, rolling them in porter, moistening the part with a little milk or sweetened milk, or drawing a little blood by a slight puncture or scratch, will usually make them bite freely. To stop the bleeding from leech-bites various plans are adopted, among which the application of nitrate of silver or creasote, or gentle pressure for some hours with the finger, are the most successful. Of late years a piece of matico leaf or soldier’s herb, applied in the same manner as a piece of lint, has been commonly adopted to stop the bleeding of leech-bites.

=LEEK.= _Syn._ PORRUM, L. The _Allium porrum_ (Linn.). Its general properties are intermediate between those of the onion and garlic. The juice is said to be powerfully diuretic, and capable of dissolving phosphate calculi.

=LEGU′MIN.= Vegetable casein. It is found most abundantly in the seeds of leguminous (podded) plants, _e.g._ beans, peas, &c., as well as in the sweet and bitter almond.

In properties it closely resembles the casein of milk.

Legumin may be obtained from peas or from almonds as follows:——After digesting the crushed seeds for 2 or 3 hours in warm water, the undissolved portion is removed by straining through linen, and the strained liquid, after depositing the starch suspended in it, is next filtered and mixed with diluted acetic acid. The white flocculent precipitate which is thus produced, is then collected on a filter and washed. It is afterwards dried, powdered, and digested, first in alcohol, and afterwards in ether.

Rochleder considered that, as thus obtained by Dumas and Cahours, it was not absolutely pure, since as it was not entirely soluble in a cold concentrated solution of potash, he recommended the alkaline solution being decanted from the undissolved portion, and again precipitated by the addition of acetic acid.

Legumin as thus prepared was believed by Rochleder to be pure, and was found on analysis to give results analogous to those furnished by casein.

In the seed, legumin occurs associated with considerable quantities of the phosphates of calcium, magnesium, and potassium. Rennet coagulates it like it does the casein of milk, its similarity to which is exemplified by the manufacture of a kind of cheese from peas and beans by the Chinese.

Dried peas contain about a fourth of their weight of legumin.

=LEM′ON.= _Syn._ LIMO, L. The fruit of the _Citrus limonum_ or lemon tree. The juice, peel, and essential oil are officinal. See OIL, and _below_.

=LEM′ON AC′ID.= See CITRIC ACID.

=LEM′ON FLA′VOUR.= See ESSENCE OF LEMON.

=LEM′ON JUICE.= _Syn._ LIMONIS SUCCUS (B. P.), SUCCUS LIMONUM (Ph. L. & D.), L. The juice of the lemon, obtained by squeezing and straining. When freshly expressed, it is turbid, owing to the presence of mucilage and extractive matter. These substances render the juice liable to decomposition, and various methods have from time to time been proposed for preserving it. Amongst these may be mentioned the addition to the fresh juice of one per cent. of bisulphite of calcium, or ten per cent. of proof spirit.

“We have examined the juice expressed from two varieties of lemons, viz. Palermo and Messina, with the following results:

Palermo. Messina. “Ounces of juice yielded by 100 lemons 108 96 Specific gravity of juice 1044·85 1038·56 Percentage of citric acid 8·12 7·04 Percentage of ash 0·289 0·301

“100 parts of the ash of the juice of Palermo lemons gave:

“Sulphuric acid 10·59 Carbonic acid 16·33 Chlorine 0·81 Phosphoric acid 6·74 Ferric phosphate 1·32 Lime 8·89 Magnesia 3·02 Potash 47·84 Soda 3·32 Silica 0·72 Loss 0·42 —————— 100·00

“If lemons are kept a few months before squeezing, the yield of juice is slightly increased, but its specific gravity and percentage of citric acid remains unaltered. It is erroneous to suppose that the acid of the lemon is, by keeping, changed into sugar. We have kept lemons for 12 months, and found that the percentage of acid was not diminished. A certain proportion of sugar was formed, but at the expense of the soluble starch contained in the cell-walls of the lemon. Lemon juice on being kept is found to decrease in density, but the amount of acid remains the same.” (Harkness.)

Lemon juice may be preserved by heating it to 150° Fahr., filtering, and setting it aside in bottles completely filled. If this process be performed in the winter, the juice, it is said, may be kept perfectly good for 12 months. Fresh lemon juice is prevented from decomposition and rendered fit for exportation by mixing it with 1/10th of alcohol. (Schweitzer.)

The Merchant Shipping Act of 1867 requires that after a ship has been at sea ten days 1 oz. of lime or lemon juice, mixed with 1 oz. of sugar and 1/2 pint of water, shall be served out to each of the crew between the hours of 12 and 1 in the day.

_Adult._ Lemon juice is frequently adulterated, the adulterants being water, sugar, or gum, and sulphuric or acetic acid. The _modus operandi_ is, to dilute the genuine juice with water, and then bring up the density with the sugar or gum, and the percentage of acid with one or other of the above acids. The examination of lemon and lime juice supplied to the navy is now conducted in the Inland Revenue Laboratory, Somerset House, and it speaks well for that department when we say that cases of scurvy on board ships are now of very rare occurrence. No juice is passed unless it comes up to a certain standard in specific gravity, and percentage of citric acid, and any sample containing any other acid is at once rejected.

_Prop._ Lemon juice is refrigerant and antiscorbutic, and has long been extensively employed in the preparation of cooling drinks and effervescing draughts, which are justly esteemed as wholesome summer beverages, as well as palliatives in fevers, nausea, &c. In scurvy, there is no remedy equal to freshly expressed lemon juice; and in acute rheumatism and gout, according to the united testimony of Dr Owen Rees, Dr Babington, and numerous Continental practitioners, it has been exhibited with considerable success. In agues, dysentery, English cholera, nausea, and vomiting, heartburn, putrid sore-throat, hospital gangrene, syphilis, and numerous skin diseases, it has proved most serviceable. See CITRIC ACID, GOUT, &c.

=Lemon Juice, Facti′′tious.= _Syn._ SOLUTIO ACIDI CITRICI, SUCCUS LIMONUM FACTITIUS, L. _Prep._ 1. Citric acid, 1-1/4 oz.; carbonate of potassa, 45 gr.; white sugar, 2-1/2 oz.; cold water, 1 pint; dissolve, add the yellow peel of a lemon, and in 24 hours strain through a hair sieve or a piece of muslin.

2. As the last, but using 15 or 16 drops of oil of lemon, to flavour instead of the lemon peel.

_Obs._ The above is an excellent substitute for lemon juice, and keeps well in a cool place. Tartaric acid, and even vinegar, are sometimes used instead of citric acid; but it is evident that it then loses all claim to being considered as an imitation of lemon juice, and to employ it in lieu of which would be absurd.

=LEM′ON PEEL.= _Syn._ CORTEX LIMONUM (B. P., Ph. L.), L. “The fresh outer part of the rind.” (B. P.) “The fresh and the dried exterior rind of the fruit;” the latter dried “in the month of April or May.” (Ph. L.) Candied lemon peel (CORTEX LIMONUM CONDITUS) is employed as a dessert, and as a flavouring ingredient by cooks and confectioners. It is reputed stomachic. See CANDYING.

=LEMON PIC′KLE.= See SAUCE.

=LEMONADE′.= _Syn._ LEMON SHERBET, KING’S CUP; LIMONADUM, L.; LIMONADE, Fr. _Prep._ 1. Lemons (sliced), 2 in no.; sugar, 2-1/2 oz.; boiling water, 1-1/2 pint; mix, cover up the vessel, and let it stand, with occasional stirring until cold, then pour off the clear through a piece of muslin or a clean hair sieve.

2. Juice of 3 lemons; yellow peel of 1 lemon; sugar, 1/4 lb.; cold water, 1 quart; digest for 5 or 6 hours, or all night, and decant or strain as before.

3. Citric acid, 1 to 1-1/2 dr.; essence of lemon, 10 drops; sugar, 2 oz.; cold water, 1 pint; agitate together until dissolved.

_Obs._ Lemonade is a pleasant, cooling summer beverage, and when made as above may be drank in large quantities with perfect safety. It also forms an excellent refrigerant and antiseptic drink in fevers and putrid diseases generally. Tartaric acid is commonly substituted for citric acid, from being cheaper; it is, however, much, inferior, being less wholesome and less agreeable. Lemonade for icing is prepared as above, only using a little more sugar. Orange sherbet, or orangeade for icing is made in a similar way from oranges.

=Lemonade, Aera′ted.= _Syn._ LIMONADUM AERATUM, L.; LIMONADE GAZEUSE, Fr. _Prep._ 1. (P. Cod.) Water, charged with 5 times its volume of carbonic acid gas, 1 pint; syrup of lemon, 2 oz.; mix.

2. (Without a bottling machine.)——_a._ Into each bottle put lemon syrup, 1 to 1-1/2 oz.; essence of lemon, 3 drops; sesquicarbonate of soda, 1/2 dr.; water, q. s. to nearly fill the bottle; have the cork fitted and ready at hand, then add of tartaric acid (cryst.), 1 dr.; instantly close the bottle, and wire down the cork; it should be kept inverted in a cool place, and, preferably, immersed in a vessel of ice-cold water.

_b._ As the last, but substituting lump sugar, 3/4 oz., for the lemon syrup.

_c._ From lump sugar, 1 oz.; essence of lemon, 3 drops; bicarbonate of potassa, 25 gr.; water q. s., as No. 1; then add citric acid (cryst.), 45 gr., and cork, &c., as before. The last is most wholesome, especially for the scorbutic, dyspeptic, gouty, and rheumatic.

_Obs._ The best aerated lemonade of the London makers is prepared by putting 1-1/2 fl. oz. of rich lemon syrup into each bottle, which is then filled up with aerated water at the bottling machine.

=Lemonade, Antimo′′niated.= _Syn._ LIMONADUM ANTIMONIATUM, L. _Prep._ By adding tartar emetic, 1 gr., to each pint of ordinary lemonade.——_Dose._ A wineglassful every 1/2 hour or hour; as a diaphoretic and expectorant. See ANTIMONY (Potassio-tartrate).

=Lemonade, Ape′′rient.= _Syn._ LIMONADUM LAXATIVUM, L. _Prep._ 1. Sugar, 1 oz.; lemon juice, 3/4 fl. oz.; sulphate of soda, 3 dr.; water, 8 fl. oz.; put them into a soda-water bottle without shaking, have the cork ready fitted, add of sesquicarbonate of soda (in cryst.), 1/2 dr., and instantly cork the bottle, wire it down, and keep it in a cool place, inverted. For a dose.

2. Heavy carbonate of magnesia, 1-1/2 dr.; refined sugar, 1 oz.; essence of lemon, 5 or 6 drops; water, 8 fl. oz.; bottle as last, then add of citric acid (cryst.), 3 dr., and instantly cork, &c., as before. For a dose. It should be kept for at least 24 hours before being taken.

=Lemonade, Lactic.= _Syn._ LIMONADUM LACTICUM, L. _Prep._ (Magendie.) Lactic acid, 1 to 4 dr.; syrup, 2 oz.; water, 1 pint; mix. Recommended in dyspepsia, &c.

=Lemonade, Milk.= _Syn._ LIMONADUM LACTIS, L. _Prep._ Take of sugar, 1/2 lb.; water, 1 pint; dissolve, add the juice of 3 lemons; milk or whey, 1/2 pint; stir the whole together and strain through a hair sieve. Some persons add a glassful of sherry.

=Lemonade, Min′eral.= _Syn._ LIMONADE MINERALE, Fr. On the Continent this name is applied to various drinks consisting of water acidulated with the mineral acids and sweetened with sugar. Thus we have limonade chlorhydrique, nitrique, phosphorique, sulphurique, &c., all of which are used as cooling drinks in fevers, inflammations, skin diseases, &c.

=Lemonade, Port′able.= See POWDERS.

=LEMONADE POWDERS.= See POWDERS.

=LEMONATED KALI.= See KALI, POTASSIUM (Citrate), &c.

=LEN′ITIVES.= In _medicine_, purgatives which act in a gentle manner, and have a soothing effect. See LAXATIVES.

=LENS.= In _optics_, a piece of glass or other transparent medium, having one or two curved surfaces, either convex or concave. A description of the different kinds of lenses belongs to a work on optics. It may, however, be useful to the chemical student to remark here that the CODDINGTON and STANHOPE LENSES, which may now be bought at any of the opticians, neatly mounted and of great power, for a few shillings, will be found of the greatest service in examining minute crystals, precipitates, &c.; and for all ordinary purposes offer a cheap and efficient substitute for more complicated microscopes. An extemporaneous instrument, possessing considerable power, may be made by simply piercing a small circular hole in a slip of metal, and introducing into it a drop of water, which then assumes a spherical form on each side of the metal, while the latter is held in a horizontal position. The ingenious little TOY MICROSCOPES sold about the streets of London, under the form of a perforated pill-box, at one penny each, consist of such a lens made with Canada balsam instead of water, which has the property of hardening without losing its transparency after exposure for a few hours to the air. A still simpler substitute for a lens is a piece of blackened card-paper with the smallest possible needle-hole pierced through it. Any very small object held in a strong light, and viewed through this hole at the distance of about an inch, will appear quite distinct, and from 10 to 12 times larger than its usual size. We have often found this little instrument of incalculable service in situations and under circumstances in which a more powerful or complicated apparatus was unattainable or could not be applied.

Another method for the manufacture of an extemporaneous lens, by Mr Francis, is the following:——Procure a piece of thin platinum wire, and twine it once or twice round a pin’s point, so as to form a minute ring with a handle to it. Break up a piece of flint glass into fragments a little larger than a mustard seed; place one of these pieces on the ring of wire, and hold it in the point of the flame of a candle or of a gas-light. The glass will melt and assume a complete lens-light or globular form. Let it cool gradually and keep it for mounting. It may be mounted by placing it between two pieces of brass which have corresponding circular holes cut in them of such a size as to hold the edge of the lens.

=LEN′TIL.= _Syn._ LENS, L. The seed of the _Ervum Lens_, a plant of the natural order _Leguminosæ_. The lentil is considerably smaller than an ordinary pea, and is of the shape of a double convex lens. Several varieties are cultivated on the Continent of Europe and in many parts of Asia, where they are largely consumed as human food. Lentils are more nourishing than any other description of pulse, but are reputed difficult of digestion, apt to disorder the bowels, and injurious to the eyes. Several alimentary preparations, sold at high prices as cures for dyspepsia, constipation, &c., contain lentil flour as the principal ingredient.

_Composition of Lentils._

Nitrogenous matter 25·2 Starch, &c. 56·0 Cellulose 2·4 Fatty matter 2·6 Mineral matter 2·3 Water 11·5 —————— 100·00 (PAYEN.)

Lentils on account of their difficult digestibility require to be very thoroughly cooked. See ERVALENTA and REVALENTA.

=LEPROSY.= _Syn._ LEPRA. A disease of the skin distinguished by circular scaly patches.

=LEPTANDRIN.= A peculiar crystalline principle obtained from the root of _Leptandra Virginica_, a North American plant belonging to the nat. order _Scrophulariaceæ_. Leptandrin is chiefly employed in American medical practice as a cathartic and cholagogue, in which latter function it has been recommended as a substitute for mercury. It is stated to be very serviceable in cases of duodenal indigestion and chronic constipation.——_Dose_, 1/4 to 1/2 grain.

Mr Wayne obtained leptandrin by adding subacetate of lead to an infusion of the root, filtering, precipitating the excess of lead by carbonate of sodium, removing the carbonate of lead by filtration, passing the filtered liquid through animal charcoal to absorb all the active matter, washing the charcoal with water till the washings began to be bitter, then treating it with boiling alcohol, and allowing the alcoholic solution to evaporate spontaneously. By dissolving the powder thus obtained in water, treating this with ether, and allowing the ether to evaporate, needle-shaped crystals were obtained, which had the bitter taste of the root. Leptandrin is soluble in water, alcohol, and ether.

=LETH′ARGY.= _Syn._ LETHARGUS, L. A heavy, unnatural sleep, sometimes bordering upon apoplexy, with scarcely any intervals of waking, from which the patient is with difficulty aroused, and into which he again sinks as soon as the excitement is withdrawn. It frequently arises from plethora, in which case depletion is indicated; or from the suppression of some usual discharge or secretion, which it should then be our business to re-establish. It also often arises from over mental fatigue and nervous debility, when relaxation from business, the use of a liberal diet, and ammoniacal stimulants and antispasmodics, are found useful. When depending on a determination of blood to the head, cupping may be had recourse to, and all sources of excitement avoided. In all cases the bowels should be moved as soon as possible by means of mild purgatives.

=LET′TUCE.= _Syn._ LACTUCA, L. The early leaves or head of the _Lactuca sativa_, or garden lettuce, forms a common and wholesome salad. They are reputed as slightly anodyne, laxative, hypnotic, and antaphrodisaic, and have been recommended to be eaten at supper by those troubled by watchfulness, and in whom there exists no tendency to apoplexy. The leaves and flowering tops of _L. virosa_ are officinal in the B. P., the “flowering herb” (LACTUCA), in the Ph. L.; the “inspissated juice,” in the Ph. E.; and the “inspissated juice and leaves,” in the Ph. D. The “inspissated juice” of _Lactuca virosa_, or strong-scented wild lettuce, is also officinal in the Ph. E.; and both the “leaves and inspissated juice” of the same variety are ordered in the Ph. D. The last species is more powerful than the cultivated lettuce. See EXTRACT and LACTUCARIUM.

=LEUCORRHŒ′A.= _Syn._ WHITES; CATARRHUS VAGINÆ, FLUOR ALBUS, L. The symptoms of this disease are well known to most adult females. The common causes are debility, a poor diet, excessive use of hot tea, profuse menstruation or purgation, late hours, immoderate indulgence of the passions, frequent miscarriages, protracted or difficult labours, or local relaxation. Occasionally it is symptomatic of other affections. The treatment must be directed to the restoration of the general health, and imparting tonicity to the parts affected. Tepid or sea bathing, or shower baths; bark, chalybeates, and other tonics; with local affusions of cold water, and mild astringent injections, as those of black tea or oak bark, are generally found successful in ordinary cases.

=LEVANT′ NUT.= See COCCULUS INDICUS.

=LEVIGA′TION.= _Syn._ LEVIGATIO, L. The process of reducing substances to fine powder, by making them into a paste with water, and grinding the mass upon a hard smooth stone or slab, with a conical piece of stone having a flat, smooth, under surface, called a ‘muller.’ Levigation is resorted to in the preparation of paints on the small scale, and in the elutriation of powders. The term is also, sometimes, incorrectly applied to the lengthened trituration of a substance in a marble or Wedgwood-ware mortar.

=LEVORACE′MIC ACID.= See RACEMIC ACID.

=LEY′DEN JAR.= _Syn._ LEYDEN PHIAL, ELECTRICAL JAR. An instrument for the accumulation of the electric fluid. Its simplest form is that of a wide-mouthed jar of rather thin glass, coated on both sides with tin-foil, except on the upper portion, which is left uncoated, and having a cover of baked wood, through which passes a brass wire, terminating in a metallic knob, and communicating with the inner coating. To charge the jar, the outer coating is connected with the earth, and the knob put in contact with the conductor of an electrical machine. The inner and outer surfaces of the glass thus become respectively positive and negative, and the particles of the glass become strongly polarised. On making connection between the two coatings with a conducting substance, discharge takes place by a bright spark and a loud snap; and if any part of the body be interposed in the circuit, a shock is felt.

=LIBAVIUS’S LIQUOR.= See TIN (TIN CHLORIDE).

=LI′CHEN.= In _pathology_, a dry papulous or pimply eruption of the skin, terminating in scurfy exfoliations. “Lichen exhibits great variety in its outward characters in different individuals; in one the pimples are brightly red; in another, of debilitated constitution, they are bluish and livid; in a third they are developed around the base of hairs; in a fourth they appear as circular groups, and increase by their circumference, while they fade in the centre, forming so many rings of various size; in a fifth, a modification of the preceding, they have the appearance of flexuous bands; while in a sixth they are remarkable for producing intensity of suffering, or unusual disorganisation of the skin. They are all occasioned by constitutional disturbance, sometimes referable to the digestive, and sometimes to the nervous system. In some instances, however, they depend upon a local cause. I have had a crop of lichenous pimples on the backs of my hands from rowing in hot weather; and in hot climates that annoying disorder called prickly heat is a lichen.” (Eras. Wilson.) The treatment of this affection is noticed under ERUPTIONS (Papular).

=LICHENS.= _Syn._ LICHENES——Juss., LICHENALES——Lind., L. In _botany_, these are cryptogamous plants, which appear under the form of thin, flat crusts, covering rocks and the barks of trees. Some of them, like Iceland moss (_Cetraria Islandica_), are esculent and medicinal and employed either as medicine or food; and others, when exposed in a moistened state to the action of ammonia, yield purple or blue colouring principles, which, like indigo, do not pre-exist in the plant. Thus, the _Rocella tinctoria_, the _Variolaria orcina_, the _Lecanora tartarea_, _&c._, when ground to a paste with water, mixed with putrid urine or solution of carbonate of ammonia, and left for some time freely exposed to the air, furnish the archil, litmus, and cudbear of commerce, very similar substances, differing chiefly in the details of their preparation. From these the colouring matter is easily extracted by water or very dilute solution of ammonia. See ARCHIL, CUDBEAR, and LITMUS.

=LIEBER’S HERBS OF HEALTH——Gesundeheitskräuter Liebersche——Blankenheimer Thee——Blankenheimer Tea=——Herba Galeopsidis Grandifloræ Concisa (Yellow Hemp Nettle).

=LIG′ATURE.= In _surgery_, a small waxed piece of cord or string formed of silk or thread, employed for the purpose of tying arteries, veins, and other parts, to prevent hæmorrhage, or to cause their extirpation. To be safe and useful they should be round, smooth, and sufficiently strong to permit of being tied with security without incurring the danger of breaking or slipping. There are many cases recorded in which emigrants, soldiers, and travellers have lost their lives from the simple inability of those around them to apply a ligature.

=LIGHT.= _Syn._ LUMEN, LUX, L. Light acts as a vivifying or vital stimulus on organised beings, just as privation of light, or darkness, disposes to inactivity and sleep. “In maladies characterised by imperfect nutrition and sanguinification, as scrofula, rickets, and anæmia, and in weakly subjects with œdematous (dropsical) limbs, &c., free exposure to solar light is sometimes attended with very happy results. Open and elevated situations probably owe part of their healthy qualities to their position with regard to it.” On the contrary, “in diseases of the eye, attended with local vascular or nervous excitement, in inflammatory conditions of the brain, in fever, and in mental irritation, whether attended or not with vascular excitement, the stimulus of light proves injurious, and, in such cases, darkness of the chamber should be enjoined. After parturition, severe wounds, and surgical operations, and in all inflammatory conditions, exclusion of strong light, contributes to the well-doing of the patient.” (Pereira.)

=LIGHT, ELECTRIC.= We believe we are correct in stating, that within the last two or three years some 600 registrations for patents, more or less, have been taken out for electricity applied to the purposes of artificial illumination. Conceding that many, if not the greater part, of these inventions may prove useless, their number is nevertheless an index of the mental activity that has lately been directed to the subject of electric lighting; and although we are far from affirming that the problem of the practical application of electricity to the lighting of our streets and dwellings may eventually be successfully thought out, still, we think, looking upon these constant endeavours to accomplish the end in view as links in the chain of that experimental evolution and gradation which has characterised the course of most great discoveries, we are justified in regarding them as not altogether improbable auguries and precursors of subsequent success.

Shortly after Faraday’s discovery in 1830 of electrical induction, or the power of a bar of magnetised steel to set up in a certain direction a current of electricity in a coil of insulated wire when introduced into it, Pixü, reducing the result of Faraday’s researches to practice, constructed an instrument, which appears to have been the first dynamic magneto-electric machine. By Pixü’s contrivance a current of electricity was generated by means of the poles of a permanent horseshoe magnet being made to revolve across those of an electro, or temporary magnet, the induced electricity set up in which in its turn established in the surrounding helix a current of electricity, which being made to escape by the terminals or ends of the wire coils could be applied to practical use.

The dynamic electro-magnetic machines of Saxton and Clarke, which succeeded Pixü’s, may be regarded as modifications of this latter, since they differed only in the arrangement of their parts and mode of action. All three machines were chiefly in use in chemical and physical laboratories, whence they have gradually been supplanted by the far more useful Ruhmkorff’s coil, a very powerful variety of the electro-magnetic instrument. In a small form Clarke’s is now chiefly used for medical purposes. That electro-magnetic machines, as cheaper and more convenient sources of electric force, should have been applied to the purposes of telegraphy, will be an obvious inference.

Among the most important and effective of the various instruments for attaining this end, it will suffice to mention the magneto-electric machine of Messrs Siemens and Halske, first brought into use in 1854.

Except, however, in the case of short distances, or with telegraphs belonging to private persons or commercial firms, these instruments have not met with very general adoption. This is owing to the great tension of the induced current, and the consequent difficulty of insulating the wire, particularly for long distances, objections from which the old galvanic apparatus is in a much greater measure free. Mr Henley was the first to use the dynamic magneto-electric machine for working the electric telegraph soon after this instrument had been adopted in England; but as we have seen, the method, except in the cases quoted, have been in great measure abandoned. A large magneto-electric machine has lately been invented by Wheatstone, the induced spark from which is used for firing mines.

The first electro-magnetic machine used for lighting purposes appears to have been one that was the joint invention of MM. Nollet and Van Malderen, of Brussels, a circumstance to which it probably owes its name of the ‘Alliance Machine.’

Nollet, who brought out his invention (which is a modification of Clarke’s) in 1850, originally designed it for the electrolysis of water, the hydrogen resulting from which it was proposed to pass through camphine, or some other hydro-carbon illuminant, and to burn as gas. Additionally it was designed to use the hydrogen as a source of motive power by exploding it in a suitably constructed engine. Owing to the improvements, however, effected in the machine by Van Malderen, by which it became a powerful generator of magneto-electricity, this purpose was abandoned. ‘The Alliance Machine’ consists of a cast-iron frame, on the circumference of which 40 powerful horseshoe magnets, each capable of supporting a weight of 120 to 130 lbs., are fixed, in eight series of 5 magnets each. A number of circular metal discs, around the circumference of which are attached sixteen bobbins of insulated wire fixed to a horizontal shelf turned by a pulley, are in such a position with regard to the magnets, that with each revolution of the shaft each bobbin passes sixteen alternate poles of the magnets, and will have had sixteen alternate currents set up or induced in it. Until replaced by the later and smaller magneto-electric machine, the ‘Alliance’ has been the one mostly employed for the production of the electric light in France, and it is still in use in the lighthouses of Hève and Grisnez, as well as in those of many other places in that country. In 1856 Mr Holmes took out a patent for a machine, which differs from Nollet’s in increasing the number of bobbins by arranging them in concentric circles between two brass discs. By this device the bobbins revolve more quickly in succession in front of the poles of the magnets, a plan which ensures the generation of a greater number of currents for every revolution.

Like the first application of Nollet’s, Holmes’ machine was used for lighthouse illumination. It was in work from December, 1858, until June, 1862, at the South Foreland lighthouse, since which time it has been removed to Dungeness, in the lighthouse of which station it has been in use ever since.

When applied to lighting purposes, both the ‘Alliance’ and Holmes’, and the other machines named, are worked in conjunction with the carbon points, which when arranged with proper machinery constitute the electric lamp.

Wild’s and Ladd’s are powerful dynamic magneto-electric instruments, capable of yielding large quantities of the electric fluid.

Artificial illumination by means of electricity has, however, been more or less occasionally practised for other than lighthouse purposes.

For instance, in 1854, during the building of the Napoleon Docks at Rouen, when 800 workmen were engaged nightly for four hours, the electric light was used for several nights with perfect success, the men being able to carry on their work at a distance of more than 100 yards from the source of the light.

In 1862 and 1863 it was frequently employed in Spain during the night in the construction of railways. During the late Franco-German war in 1870 it was applied to submarine illumination, and more lately it has been used in a series of street illumination in St Petersburg.

The electric light apparatus was placed on the tower of the Admiralty Buildings of that city, and by means of it three of the larger streets were illuminated at night from 7 until 10 o’clock. In this latter case, as well as in that of the Rouen Docks, the lamps were supplied with the electric current generated in batteries.

It may be said, however, to have been only within the last two years that the question of electric lighting has developed into a burning one, and that the light itself has become so much more generally and extensively adopted.

This new era in the history of artificial illumination may be said to date from the introduction of two forms of dynamic magneto-electric apparatus, the one invented by Dr Siemens, the eminent telegraphic engineer, the other by M. Gramme, of Paris, who, from having been formerly a journeyman carpenter, has now become the head of a manufacture which forms a most important branch of scientific industry.

In the apparatus of Gramme and Siemens three marked features and improvements over the older machines have been achieved:——

1. A great reduction in size, and, consequently, in cost, and requisite space for the machine.

2. The method of generating large quantities of electricity by the mutual action between the different parts of the same machine, and the induction therein set up.[14]

[Footnote 14: This discovery was made independently and nearly simultaneously by Drs Siemens and Sir Charles Wheatstone.]

3. The production of the electric current at a much less expenditure of motive power.

On this latter point Professor Tyndall, in his report to the elder brethren of the Trinity House, states that magneto-electric machines of old construction cost ten times more, occupied twenty-five times the space, and weighed fourteen times as much as the recent machines, while they produced only one-fifth of the light with practically the same driving power; which in effect amounts to this——that taking illuminating effect in each case into consideration, the new machines cost one-fiftieth, and are, as regards space occupied, 125 times more advantageous than the earlier forms.

In all the older and larger machines the current of electricity, as it was given off from the wire and passed through the carbon points, was alternate, or first in one direction and then in the opposite——that is, it was a momentary current, first positive and then negative.

In Siemens’ machine, and in one form of Gramme’s, the current is direct——that is, it pursues one uniform course in its passage through the carbon points of the lamp, and in its circuit from the terminal of one wire to that of the other.

Scientific opinion is somewhat at variance as to the disadvantages of the indirect current; many electricians consider that it causes the partial destruction of the contacts, and sets up unnecessary heat in the machine. In magneto-electric machines employed in electro-metallurgic operations, it is essential the current should be a direct one.

In the Gramme machine the electro-magnet consists of a ring composed of soft iron wire attached to a horizontal spindle or axis, which latter is turned by an endless strap revolving on a pulley. Around this iron ring are wound a number of coils, each having 300 turns, of insulated copper wire, each coil being bent inside the ring, and fixed to an insulated piece of brass.

The wire being continuous, each coil is connected with the adjacent one, the whole of the coils thus forming a single conductor. The series of pieces of brass to which the wire is soldered are formed into a circle, which surrounds the axis of the machine, each piece of brass being insulated from its neighbour. The iron-wire ring with its attachments is so arranged, that when the shaft or axis to which it is fixed is turned, it revolves between the poles of a powerful horseshoe magnet in the same plane with it. As it turns the ring gives rise in the coils to two different and diverse currents of electricity, one in one half of the coils around the ring, and the other in the other half.

These currents are made to pass to the circle composed of the insulated pieces of brass, which are arranged radially to the axis of the machine.

Two brass brushes press against these insulated brass radii, one on each side.

These brushes are connected one to each terminal of the machine, and so contrived as always to be in contact with the coils, not becoming insulated from one coil until contact is established with the next one, an arrangement which gives rise to a continuous current of electricity always, and in the same direction.

The Gramme, although of very small dimensions, is an extremely powerful machine. It easily decomposes water, and will heat an iron wire 8 inches in length and a 25th of an inch in diameter to redness.

The following description of the Siemens magneto-electric machine is from a paper read some few months back at the Society of Arts by Dr Paget Higgs, and is extracted from the journal published by that body:

“In the latest form of construction of the Siemens magneto-electric machine the armature, as the revolving coil may be called, consists of several lengths of insulated copper wire, coiled in several convolutions upon a cylinder. The whole surface of the cylinder is covered with wire, laid on in sections, each convolution being parallel to its longitudinal axis. For about two thirds of its surface the wire cylinder is surrounded by curved iron bars, there being just sufficient space left between these curved iron bars and the wire cylinder to allow of its free rotation. The curved iron bars are prolongations of the cores of large, flat electro-magnets; the coils of these electro-magnets and the wire on the cylinder (from brush to brush) form a continuous electrical circuit. On revolving the cylinder (which is supported on a longitudinal axis in suitable bearings, the axis carrying a pulley) an initially weak current is generated into its wires by their passage through the magnetic field, formed by the residual magnetism of the iron coils of the electro-magnets, and the current being directed into the coils of the electro-magnets, increases the magnetism of the cores, which again induce a stronger current in the wire cylinder. This material action may continue until the iron has attained its limit of magnetisation. The maximum magnetic power acting upon each convolution is attained at every revolution of the armature, when the convolution passes through the centre of both magnetic fields, and gradually falls to zero as the convolution becomes perpendicular to that position. Each convolution has, therefore, a neutral position, and a convolution leaving that position on the one side of the axis and advancing towards the north pole of the electro-magnet would be subject to a direct induced current, and that portion of the convolution on the opposite side of the axis would be traversed by a current of opposite direction as regards a given point, but of the same direction as regards circuit. Each of the sections of wire coiled upon the cylinder consists of two separate coils, leaving four ends; two of these ends are connected to each of the segments of a circular commutator divided into parts. But all the coils are connected to the several segments of commutator in such a manner that the whole of the double sections form a continuous circuit, but not one continuous helix. Two brushes placed tangentially to the segments of the commutator collect the electric currents; these brushes are connected one to each electro-magnet, and the two free ends of the electro-magnet coils are connected to the conducting wires leading to the lamp.

“The dimensions, weight, number of revolutions made by the armature, light equivalent in normal candles, and horse-power required for driving, are for the three sizes of machines as follows:——

+----------------------+-------+------------+--------+------------+ | Dimension in Inches. |Weight |Revolutions |Candles’|Horse Power.| +-------+------+-------+in lbs.|of cylinder.| Light. | | |Length.|Width.|Height.| | | | | +-------+------+-------+-------+------------+--------+------------+ | 25 | 21 | 8·8 | 298 | 1100 | 1,000 | 1-1/2 to 2 | | 29 | 26 | 9·5 | 419 | 650 | 6,000 | 3-1/4 to 4 | | 44 | 28·3 | 12·6 | 1279 | 480 | 14,000 | 9 to 10 | +-------+------+-------+-------+------------+--------+------------+

“In the lamp which it is preferred to use with the Siemens machine, the points of the carbons after being separated are brought together again by the gravitation of the top carbon and its holder. The descent of the top carbon actuates by means of the straight rack it carries at its lower end, a large pinion, the spindle of which carries a small pinion, gearing into a second neck attached to the lower carbon holder, the superior weight of the top carbon and holder, in conjunction with the multiplying ratio of the two pinions, producing a continual tendency of the carbons to approach each other. The large and small pinions are connected to each other, and to the spindle that carries them, by an arrangement of friction discs, and the object of this construction is to allow of the two racks being moved equally and simultaneously up or down for the purpose of focussing the light when required. This movement is effected by means of bevelled gearing, and actuated by a milled head, which can be pressed into position when required. On the spindle carrying the large and small pinions and the friction discs is placed a toothed wheel, connected with the spindle by a pawl and ratchet.

“This wheel is the first of a train of wheels and pinions driving a regulating fly in the usual way. The pawl and ratchet are provided to allow of the rapid distancing of the carbon holders when it becomes necessary to introduce fresh carbons. The spindle of the fly also carries a small finely-toothed ratchet wheel. This ratchet wheel is actuated by a spring pawl, carried at the end of a lever, which lever is the continuation of the armature of the electro-magnet, in such a manner that when the armature is attracted by the electro-magnet, the spring pawl engages in the teeth of the ratchet wheel, and causes the wheels in gearing therewith to act upon the racks of the carbon holders to draw them apart.

“The action of the lamp is as follows:——The current passes from the conductor to the top carbon holder, thence through the carbons to the bottom carbon holder, then to the coils of the electro-magnet situated in the base of the lamp. From the coils of the electro-magnet the circuit is completed to the other conductor. Upon the current passing through the circuit, the armature of the electro-magnet is attracted, and the abutment from the armature lever caused to short-circuit the coils of the electro-magnet, releasing the armature. The armature being released, the short-circuit is removed from the coils of the electro-magnet, and the cycle of movement repeated; in this manner an oscillatory motion is given to the armature lever, which by the spring pawl actuates the ratchet wheel, the train of clockwork, and the racks of the carbon holders, forcing the carbons apart until the distance between their points sufficiently weakens the current, so that it no longer attracts the armature of the electro-magnet. Thus, by the combined action of gravitation of the top carbon in drawing the carbons together, and of the current to separate the carbons when they approach too closely, a working distance is maintained between the points with perfect automatism.”

Siemens’ lamp is at the present time employed in the Lizard Lighthouse, in Messrs Siemens’ Engineering Works in England and Wales, as well as in other localities or buildings requiring powerfully lighting up.

An interesting illustration of the value of the electric light to the sailor is furnished by the ‘Telegraph Journal’ of April 5th, 1878. This publication contains a letter from the captain of the S.S. ‘Faraday,’ narrating how that vessel was by its means prevented from running into another vessel during a dense fog.

Siemens’ magneto-electric apparatus and lamp were used on the occasion above referred to.

In every form of contrivance for electrical illumination the lamp or lighting apparatus consists of carbon points separated by a very slight interval, through which the current of electricity passes by means of terminal wires attached to the dynamo-electrical machine.

The lighting effect is produced by the passage of the electric spark through the small gap which separates the carbon points, in which interval extremely minute but solid particles of carbon, given off by the points, are heated up to incandescence in the path of the spark, and thus give rise to the intensely luminous focus known as ‘the electric light.’ The brilliancy of the light of course depends upon the quantity of electricity employed.

A very large number and variety of designs and patents for electric lamps have made their appearance in England, America, France, and Russia within the period following the invention of the small, powerful, and economic dynamo-electric machines of Siemens and Gramme.

The lighting apparatus generally attached to and worked by that variety of Gramme’s machine generating the continuous current is that known as the ‘Serrin Lamp.’ Two carbon electrodes placed vertically one above the other (the positive being the upper one) are fixed on brass holders, which are so connected by a suitably contrived clockwork movement, combined with the working of an electro-magnet in connection with the electric circuit, as to maintain the two carbon poles during their combustion at the necessary distance from each other. Serrin’s lamp differs in detail from Siemens’, but, like this latter, is automatic in principle. In Paris it was the one in general use until the introduction of the Jablochkoff candle, and, with the Duboscq lamp, may be looked upon as the precursor of the various lamps and regulators now employed in electric lighting. Serrin’s lamp or regulator, with some slight modification in the machinery, is also used in the Lontin system of electric illumination, by which separate lights are supplied by separate circuits of electricity. Lontin’s method is that by which the Gaiety Theatre in the Strand is lighted; and is also used at the Western Railway Station (Gare, St Lazare) at Paris. The Jablochkoff candle, which in Paris has lately superseded the Serrin lamp, probably because its use renders unnecessary the use of automatic machinery, is the invention of a Russian engineer, whose name it bears.

It consists of two sticks of gas carbon, about 9 inches long and 1/5th of an inch thick, which are placed vertically side by side, and insulated from one another by a very thin strip of kaolin or china clay (a silicate of alumina and potash), the whole forming a candle. Each carbon rod is connected with one of the terminal wires of a Gramme dynamo-electric machine, the electric current from which, however, not being continuous, sets up an alternate current between the tips or poles of the candles, which are gradually consumed like an ordinary taper, and with this only difference in action between Serrin’s and Siemens’ lamps, that whereas in these latter the spark passes from the top to the bottom carbon point, in the Jablochkoff candle it jumps from side to side. The inventor contends that the kaolin by becoming heated diminishes the resistance of the circuit, and thus permits of the passage of the electric spark more easily through the carbons, and also, we believe, asserts that the kaolin being electrolytically decomposed as the carbons are consumed, becomes converted into silica, which melts and drops down, whilst the aluminium liberated contributes luminosity during combustion to the flame.

One of the chief advantages, however, claimed by M. Jablochkoff is, that he can divide the circuit into a number of different lights, as the resistance of the circuit is uniform.

A large number of Jablochkoff candles are employed in the celebrated ‘Magasins du Louvre,’ one of the most extensive commercial establishments in Paris for the sale of silks, ribbons, gloves, &c., and clothing of every description.

The pure white light diffused by electricity admirably adapts it for viewing colours of all kinds at night, whether seen in pictures or on fabrics and raiments, and more particularly blues and greens, the hues of which are frequently indistinguishable from each other by gaslight. The candle is also used to light the courtyard of the Hotel du Louvre, a large building contiguous to, and with its apartments running over, the Magasins, as well as in several shops.

Jablochkoff’s system is also in work in Paris in front of many public buildings, and by its means the Place and Avenue de l’Opera, together occupying a space 900 yards long by 30 wide, are brilliantly illuminated every night.

That celebrated circus, so well known to every visitor to Paris, the Hippodrome, is also lighted by it.

Another form of electric lamp is that of M. Rapieff, now in use in the machine-room of the ‘Times’ newspaper office. In this lamp there are four carbon points instead of two. M. Rapieff, like M. Jablochkoff, states that by means of his system he is enabled to supply several lamps with the same electric current. In the Wallace-Farmer lamp slabs of carbon instead of points are had recourse to.

In the lamps of M. Regnier in one variety two revolving carbon discs are used, whilst in another a rod of carbon descends upon a disc of the same material, an arrangement which the inventor states leads to the subdivision of the current and its separate utilisation by a number of such lights.

One of the latest and apparently most successful methods for dividing the electric current, so that one and the same current shall be made simultaneously to supply and render incandescent a series of carbon points, and in so doing give rise to as many effective electric illuminators, is that of Mr Werdermann. Mr Werdermann, observing the disparity of consumption between the positive and negative poles of the electrodes, found by experiment that when the sectional area of the negative pole was sixty-four times greater than the positive one, the electric arc was so far reduced, that the two carbons were in contact. Under these conditions the electric arc was infinitely small, the negative electrode was not consumed, whilst the positive one was incandescent. Two supplies of electric light, therefore, ensued, one by the electric arc, and the other by the incandescent carbon of the positive electrode. Under these circumstances, if it were possible to devise a plan by which the positive pole as it consumed should be kept in uniform contact with the negative pole, the difficulty which had hitherto proved the stumbling-block to using a series of lights from one current would be annihilated.

Mr Werdermann demonstrated the correctness of his premises by a practical illustration of his plan very lately (November, 1878) at the British Telegraph Manufactory, 374, Euston Road. The current from a dynamo-electric Gramme machine of 2-horse power was conducted to two electric lamps, each having an illuminating value equal to 360 candles each. The light so produced is described by a spectator as “being soft and sun-like, and as being capable of being looked at without discomfort, though it was not shaded.” These being extinguished, ten smaller lamps were ignited by means of the same current, each one having an illuminating power equal to forty candles. “The lamps burned steadily with a beautiful soft and clear white light. First one of the ten lights was then extinguished, and afterwards a second, the only effect on the remainder being that they became slightly more brilliant.”[15]

[Footnote 15: ‘Daily News.’]

Unlike Mr Edison, Mr Werdermann does not believe in the indefinite divisibility of the electric light. It will be observed that the candle power of the light becomes diminished by subdivision. Two lights gave a light equal to 700 candles, whereas the same current divided into ten lights gave an aggregate light of only 400 candles.

The following extract from the ‘Times’ of December 5th, 1878, illustrates the financial aspect of the electric light question:——

“At the usual weekly meeting of the Society of Arts, held last evening, Dr C. W. Siemens, F.R.S., in the chair, a paper on electric lighting was read by Mr J. N. Shoolbred, M. Inst. C.E. The object of the author was to present some results of the application of electric lighting to industrial purposes, especially as regards cost. He noticed first the Holmes and the Alliance magneto-electric machines, giving alternating currents and single lights for lighthouse use. Secondly, he referred to the dynamo-electric machines, producing single lights for general industrial purposes, as well as for lighthouses, and including the Siemens and the Gramme machines. In his third group the author included the machines used for producing divided lights, each group indicating a marked period representing a clearly defined stage of progress in electric lighting. With regard to cost, Mr Shoolbred stated that in every instance his figures and particulars were those afforded by the users of the various lights, and not by the inventors or their representatives. In the case of the Holmes machine the annual cost per lighthouse was about £1035, inclusive of interest, repairs, and wages. With the Siemens machine the annual cost was about £494 per lighthouse, including interest and the other expenses. With the Alliance machine as used at Havre the cost was about £474 per annum per lighthouse, interest, &c., included. The single-light Gramme machine has been in use in the Paris goods station of the Northern of France Railway for two years. Six machines have been kept going with one light each, and the cost is found to be 5_d._ per light per hour, or with interest on outlay at 10 per cent., 8_d._ per hour. The same light at the ironworks of Messrs Powell at Rouen was stated to cost 4_d._ per light per hour, exclusive of interest and charge for motive power, the latter being derived from one of the engines on the works. In 1877 a series of experiments were carried out with the Lontin light at the Paris terminus of the Paris, Lyons, and Mediterranean Railway. The passenger station was lighted, and the results were so satisfactory that the company have entered into a permanent contract with the proprietors of the Lontin light for lighting their Paris goods station with 12 lights, at a cost of 5_d._ per light per hour. The Western of France Railway Company have had 6 Lontin lights in the goods station at the Paris terminus, St Lazare, since May last, and 12 lights in the passenger station since June. Careful experiments have shown the cost to be 8_d._ per light per hour, inclusive of interest. Referring to the Jablochkoff light, Mr Shoolbred placed before the meeting some particulars with regard to its application in the Avenue de l’Opéra, Paris, which were afforded him by M. J. Allard, the chief engineer of the lighting department of the City of Paris. It appears that the authorities pay the Société Générale d’Électricité 37f. 2c. per hour for the 62 lamps in use there. These 62 lamps supersede 344 gas-jets which were previously used, and which cost the authorities 7·244f. per hour. The electric illumination, however, is considered as equal to 682 gas-jets, or about double the original illumination——that is, to a cost of 14·45f. per hour as against 37·2f. for the electric light, the cost of which, therefore, is 2·6 times that of the gas. The contract for lighting by electricity was terminated by the City of Paris on the 30th ult., and the authorities have declined to renew it except at the price paid for gas, namely, 7·224f. (or about 6_s._) per hour, and that only until the 15th of January next. These terms have been accepted by the Société, so that the price paid to them will be at the rate of about 1-1/8_d._ per light per hour. Mr Shoolbred stated that the Société place their expenses at 1·06f. (or just 11_d._) per light per hour, which, however, they hope shortly to reduce by one half. A series of careful photometric experiments carried out by the municipal authorities with the Jablochkoff lights, above referred to, showed each naked light to possess a maximum of 300 candles of intensity. With the glass globe this was reduced to 180 candles, showing a loss of 40 per cent., while during the darker periods through which the lights passed the light was as low as 90 candles. The foregoing were the only authenticated particulars which the author could obtain as regards the working of the various electric systems of electric lighting. In conclusion, Mr Shoolbred referred to the Rapieff light at the ‘Times’ office, which, he observed, worked fairly and with regularity, which could not be said of all others, and it might therefore be entitled to take rank as an established application of electric illumination. The paper was illustrated by the Siemens, Rapieff, Serrin, and other forms of electric light, which were shown in operation.”

That the electric light is eventually destined to supplant coal gas in illuminating the fronts of large buildings, open spaces, squares, assembly rooms, public halls, theatres, picture galleries, workshops and factories, &c., seems no very extravagant prediction. We have already seen that it has for some years been employed in one lighthouse; and we have the testimony of Mr Douglas, of the Trinity House, at a very recent meeting of the Society of Arts, that at the Souter Point Lighthouse there had been only two stoppages in eight years, once through a bad carbon breaking, and once through the lighthouse-keeper going to sleep.

In addition to places above specified, amongst other localities in which it is in work, we may mention the chocolate factories of M. Menier, at Noiselle, his india-rubber works at Grenelle, his sugar refinery at Nice, and Messrs Caille’s works at Paris. In this country it was employed in the erection of the Tay Bridge, as well as in the works of Messrs Head, at Stockton-on-Tees, and in London it may be nightly seen burning before the Gaiety Theatre in the Strand, at Billingsgate Market, and frequently lighting up the front of the Stereoscopic Company’s premises in Regent Street. Further, we may add that the Metropolitan Board of Works are making the experiment of lighting the Victoria Embankment and the City authorities the Holborn Viaduct, with the Jablochkoff candle. The former have placed a dynamo-electric apparatus, worked by a steam engine of 20-horse power, close to the foot of Hungerford Bridge, from whence wires will be carried right and left towards Westminster and Blackfriars respectively.

We believe the main conducting wire is carried under the coping-stone of the parapet running along the Embankment, and that the carbon points are fixed on the top of a certain number of gas standards which now surmount the wall of the Embankment.

That electricity is more economical as a method of artificial lighting than coal-gas the figures previously given seem to demonstrate, and there can be no question as to the much greater luminosity and purity of the light over the gas flame, qualities which render it an admirable substitute for the sunlight, the absence of which it may be said to supply at night. One disadvantage urged against its employment in weaving rooms is, that it casts such dark and distinct shadows that these are frequently mistaken for the threads themselves, an objection which is said to have been remedied by placing the light as near the ceiling as possible. The non-generation of carbonic acid and sulphurous products such as are given off by burning gas, although of slight importance when the light is employed in the open air, becomes a great advantage when it is used in crowded assembly rooms or theatres, since the atmospheric contamination caused by carbonic acid becomes of course considerably reduced. The absence of sulphur compounds especially qualifies the light for use in large libraries. If it be true that the light gives rise to an appreciable amount of ozone, this constitutes another point in its favour. Opinion is at variance as to the possibility of the practical application of the electric light for illuminating private houses and dwellings in such a manner as to supply the place of the gas we now burn in them. One serious impediment to the probable accomplishment of this result certainly seems to be the fact that electricity for lighting purposes can only practically be conveyed to short distances from its source, which would necessitate the establishment and supervision of a number of generating machines near the houses to be lighted. Another obstacle, which hitherto has not been overcome, is the circumstance that the current when subdivided yields proportionately a greatly diminished amount of light. For instance, one light which had a certain photometric candle valve would yield when divided into two an aggregate amount of light considerably less than the one; and if divided into three still less, and so on. This has been pointed out when noticing Mr Werdermann’s invention for the divisibility of the light. Mr Edison, an American inventor, asserts that he has conquered this difficulty, and additionally perfected a machine for measuring the current used in the electric light. He states that it consists of an apparatus placed in every house lighted by electricity, which registers the quantity of electricity consumed, and uses for the purpose 1000th part of the quantity employed in the building.

Dr Siemens, no mean authority, doubts the practicability of applying electric lighting to household illumination.

A matter of primary importance in connection with the successful working of the electric light is the quality of the carbon points. In their manufacture gas carbon obtained from the necks of the retorts used in gas-making, as being the hardest and purest, is employed.

Superior, however, as this form of carbon is to every other description of the substance, it is never chemically pure, and as any foreign substance imparts to the light the irregularity or flickering that sometimes accompanies it, it is necessary the impurities should be removed. To effect their separation the carbon has to undergo several processes, such as soaking in caustic potash to remove the silica, treatment with strong acids, several washings, grinding, &c. It is then kneaded and put into moulds, in which it is subjected to a pressure as high as 12 tons to the square foot. Subsequently the points so made are baked.

=LIGHTNING.= See ACCIDENTS.

=LIG′NIN.= C_{6}H_{10}O_{5}. _Syn._ CELLULOSE. This is woody fibre deprived of all foreign matter. It forms about 95 per cent. of baked wood, and constitutes the woody portion of all vegetable substances. Fine linen and cotton are almost entirely composed of lignin, the associated vegetable principles having been removed by the treatment the fibres have been subjected to during the process of their manufacture.

Pure lignin is tasteless, inodorous, insoluble in water and alcohol, and absolutely innutritious; dilute acids and alkaline solutions scarcely affect it, even when hot; oil of vitriol converts it into dextrin or grape sugar, according to the mode of treatment. When concentrated sulphuric acid is added very gradually to about half its weight of lint, linen rag, or any similar substance shredded small, and contained in a glass vessel, with constant trituration, the fibres gradually swell up and disappear, without the disengagement of any gas, and a tenacious mucilage is formed, which is entirely soluble in water. If, after a few hours, the mixture be diluted with water, the acid neutralised by the addition of chalk, and, after filtration, any excess of lime thrown down by the cautious addition of a solution of oxalic acid, the liquid yields, after a second filtration, and the addition of alcohol in considerable excess, a gummy mass, which possesses all the characters of pure dextrin. If, instead of at once saturating the diluted acid solution with chalk, we boil it for 4 or 5 hours, the dextrin is entirely converted into grape sugar, which, by the addition of chalk and filtration, as before, and evaporation by a gentle heat to the consistence of a syrup, will, after repose for a few days, furnish a concrete mass of crystallised sugar. By strong pressure between folds of porous paper or linen, redissolving it in water, agitation with animal charcoal, and recrystallisation, brilliant colourless crystals of grape sugar may be obtained. Hemp, linen, or cotton, thus treated, yield fully their own weight of gum, and 1 per cent. of their weight of grape sugar. During the above transformation, the sulphuric acid is converted into sulpholignic acid, and may be procured in a separate state. A solution of oxide of copper in ammonia, or solution of basic carbonate of copper in strong ammonia, dissolves cotton, which may then be precipitated by acids in colourless flakes.

=LIG′NITE.= _Syn._ BROWN COAL. Wood and other matter more or less mineralised and converted into coal. The lignites are generally dark brown, and of obvious woody structure. They are distinguished from true coals by burning with little flame and much smoke. Those of Germany are largely used as a source of paraffin and burning oils.

=LIG′NUM VI′TÆ.= See GUAIACUM WOOD.

=LIME.= CaO. _Syn._ OXIDE OF CALCIUM; CHAUX, Fr.; KALK, Ger. Lime, when pure, and as a chemical and medical reagent, will be found treated of under CALCIUM (Oxide of). It is prepared on the large scale for commerce by calcining chalk, marble or limestone, in kilns, and is called quicklime, caustic lime, burnt lime, stone lime, &c. The lime kilns are usually of the form of an inverted cone, and are packed with alternate layers of limestone and fuel, and the burnt lime raked out from the bottom. The lime thus obtained is a pale yellow powder, combining eagerly with water, and crumbling to a light white powder, “slaked lime,” with the evolution of much heat. Lime which slakes well is termed “fat lime,” while if it slakes badly is termed “poor lime.” The slaked lime, the CALCIS HYDRAS of the B. P., is fresh lime sprinkled with water till it falls to powder.

=Lime, Salts of.= See under CALCIUM.

=Lime, Pyrolignite of.= An impure acetate of calcium used for making mordants in dyeing and calico printing, as a substitute for the more expensive acetate of lead.

=Lime, Chloride of.= _Syn._ BLEACHING POWDER, CHLORINATED LIME, HYPOCHLORITE OF CALCIUM.

This article was formerly believed to be a compound of lime and chlorine (CaO.Cl), and consequently received the name of ‘chloride of lime.’ We now know, however, that it is not a definite substance, but a mixture of calcium hypochlorite, calcium chloride, and calcium hydrate. The value of this preparation is due to the readiness with which the calcium hypochlorite is decomposed by acids, even by the carbonic acid of the air, with the evolution of hypochlorous acid which abstracts hydrogen from many vegetable colouring matters, badly smelling gases, &c.: the former are thereby bleached and the latter deodorised.

Chloride of lime is most extensively used for bleaching linen, calico, and similar fabrics, thousands of tons being made near Newcastle alone every year. It is also largely employed as a deodoriser.

_Prep._ Freshly slaked lime is thinly spread out in a proper vessel and exposed to an atmosphere of chlorine gas until it is saturated. Now included in the Materia Medica.

Slaked lime (fresh), 20 parts, common salt, 1 part, are mixed together, and the powder placed in long earthenware vessels into which chlorine is passed until the mixture begins to grow damp, or until one part of it, dissolved in 130 parts of water, is capable of decolouring 4-1/2 parts of sulphate of indigo (see CHLORIMETRY), when the whole is transferred to dry bottles.

(Wholesale.) The chlorine is generated from the usual materials mixed in leaden vessels, heated by steam, and the gas, after passing through water, is conveyed by a leaden tube into an apartment built of siliceous sandstone, and arranged with shelves or trays, containing dry fresh slaked lime, placed one above another, about an inch asunder. The process, to produce a first-class article, is continued for 4 or 5 days. During this time the lime is occasionally agitated by means of iron rakes, the handles of which pass through boxes of lime placed in the walls of the chamber, which thus act as valves.

The successful manufacture of bleaching powder is dependent upon the careful observance of a number of conditions, such as the quality of the limestone,[16] which should be free from iron; the presence of magnesia at the time is also very objectionable, since it gives rise to the formation and presence in the bleaching powder of deliquescent chloride of magnesium; the apportionment of the water in slaking the lime is also a matter of no inconsiderable importance, the lime forming into balls, which fail to properly absorb the gas if the water be insufficient, whilst if it be in excess, it yields a powder deficient in chlorine. When slaked, the lime is passed through a sieve to free it from small pebbles. After being slaked it is kept for 2 or 3 days before being used, as it is found that under these circumstances it absorbs chlorine more readily than when recently prepared. Previous to its entrance into the lime chamber, the chlorine is passed through water, to free it from vapour, and solid particles of chloride of manganese.

[Footnote 16: A very pure kind of limestone, and one which is largely used in the preparation of bleaching powder, is found at Buxton.]

The temperature of the chamber into which the chlorine is passed ought not to exceed 62° F. An excess of chlorine has been found to yield a powder deficient in hypochlorite.

Bleaching powder, unless protected from the air (carbonic acid), slowly parts with its chlorine. In summer it has been estimated that it loses as much as 86 per cent. of the gas, and in winter about 26 per cent.

_Prop., &c._ Chloride of lime is a pale, yellowish-white powder, generally more or less damp, and evolving a chlorine-like odour of hypochlorous acid. Its soluble constituents dissolve in about 20 parts of water. It is decomposed by acids with the evolution of chlorine and oxygen (hypochlorous acid). Good chloride of lime should contain from 32% to 36% of chlorine, of which, however, but 25% to 30% can be easily liberated by an acid.

_Estim._ See CHLOROMETRY.

_Uses._ Chloride of lime is employed in medicine as a deodoriser and disinfectant. An ointment of chloride of lime has been used in scrofula, and a lotion or bath, moderately dilute, is one of the cleanest and readiest ways of removing the ‘itch,’ and several other skin diseases. It is also in great use as a disinfectant, and may be used either in substance or solution. A small quantity of the powder spread on a flat dish or plate, and placed on the chimney-piece, and a like quantity in an opposite part of the room, will continue to evolve sufficient chlorine or hypochlorous acid to disinfect (? Ed.) the air of an apartment for several days. The evolution of chlorine is promoted by occasionally renewing the exposed surface, by stirring it with a piece of stick, and after it becomes scentless, by the addition of a little acid, as strong vinegar, or hydrochloric acid, or oil of vitriol, largely diluted with water. Of late, however, it has been partly superseded by sulphurous acid, carbolic acid, &c. The most extensive consumption of chloride of lime is, however, for bleaching textile fabrics. When employed for this purpose, the goods are first immersed in a dilute solution of this substance, and then transferred to a vat containing dilute sulphuric acid. The chlorine thus disengaged in contact with the cloth, causes the destruction of the colouring matter. This process is generally repeated several times, it being unsafe to use strong solutions. White patterns may thus be imprinted upon coloured cloth; the figures being stamped with tartaric acid thickened with gum water, the stuff is immersed in the chloride bath, when the parts to which the acid has been applied remain unaltered, while the printed portions are bleached white.

_Concluding Remarks._——Chloride of lime is now scarcely ever made on the small scale, as it can be purchased of the large manufacturer of better quality and cheaper than it could possibly be made by the druggist. The chief precaution to be observed in the manufacture of good bleaching powder is to maintain the ingredients at a rather low temperature.

=LIME.= The fruit of _Citrus limetta_. It resembles the lemon, but is smaller and has a smoother skin. It is imported into Great Britain in a preserved state for use as a dessert. Its juice is also largely imported for the preparation of CITRIC ACID, and for the prevention of scurvy on board ship (see _below_).

=LIME JUICE.= _Syn._ LEMON JUICE. The juice of the fruits of various species of _Citrus_, principally LIMES, is known in commerce under these names. It is very variable as to quality, which depends upon the method of extraction, the quality of the fruit, and the honesty of the shipper.

We have examined the juice expressed from limes sent from the West Indies, from Jamaica, and from South Africa, with the following results:

W. Indies. Jamaica. S. Africa. Specific gravity of juice 1041·30 1044·18 1044·90 Per cent. of citric acid 7·96 8·66 8·50 Per cent. of ash 0·321 0·401 0·364

The yield from limes is very small, and the freshly expressed juice contains a large amount of pulp. This, however, on standing a few weeks, separates, and a clear sherry-coloured liquid is obtained.

A concentrated lime or lemon juice is used by calico printers. It is a “dark, treacly-looking fluid, marking from 48° to 54° Twaddell,” and contains about 30 per cent. of pure citric acid.

_Adult._ See LEMON JUICE.

_Estim._ Lime juice is only valuable on account of the citric acid it contains. If of good quality, 100 gr. will neutralise from 70 to 76 gr. of pure crystallised carbonate of soda. “For commercial purposes each grain of carbonate of soda neutralised may represent a half grain of crystallised citric acid (equal to 38 gr. of dry acid), and the value of the lime juice be calculated in proportion.” (O’Neill.) As commercial lime juice contains variable proportions of vegetable extractive matter, the indications of the hydrometer cannot be depended upon. ACIDIMETRY, CITRIC ACID, &c.

=LIME′STONE.= A general term applied to a great variety of rocks in which carbonate of lime is the principal constituent.

_Estim._ The value of chalk, limestone, marble, &c., for hydraulic mortars and cements, may be determined as follows:

A given weight (say 100 gr.) of the sample is reduced to powder and digested in hydrochloric acid dilated with about an equal weight of water, with frequent agitation for an hour or longer; the mixture is then diluted with thrice its volume of water, thrown upon a filter, and the undissolved portion washed, dried, ignited, and weighed. This weight indicates the per-centage of clay and silica or sand, and the loss that of the lime or calcium oxide, magnesium oxide, and ferric oxide, present in the substance examined. In most cases these results will be sufficient to show the quality of the limestone for the purpose of making mortar or cement.

The filtrate and the washings are mixed together, and ammonia is added in excess; the bulky, reddish-brown precipitate is collected, washed, dried, ignited, and weighed. This gives the per-centage of ferric oxide.

The filtrate from last is then treated with oxalate of ammonium, and the quantity of lime determined in the manner described under the head of CALCIUM.

The liquid filtered from the precipitate in last is boiled for some time with carbonate of potassium until ammoniacal fumes are no longer evolved; the precipitate is then collected on a filter, washed with hot water, dried, and strongly ignited for 3 or 4 hours, and, lastly, weighed. This gives the per-centage of magnesium.

=LINC′TUS.= [L., Eng.] _Syn._ LOCH, LOHOCH, LINCTURE, LAMBATIVE; LOOCH, Fr. A medicine of the consistence of honey, intended to be licked off a spoon. This form of medicine is well adapted to females and children, but is not much used in England at the present time. Those employed in modern pharmacy and prescribing are included under the heads CONFECTION, CONSERVE, or ELECTUARY.——The _Dose_, when it is not otherwise stated, is a teaspoonful occasionally.

=Linctus, Acid.= (Dr Copland.) _Syn._ LINCTUS ACIDUS. _Prep._ Honey of roses, 10 dr.; hydrochloric acid, 20 minims; syrup of red poppies, 2 dr. Mix.

=Linctus of Borax.= (Univ. Coll. Hosp.) _Syn._ LINCTUS BORACIS. _Prep._ Borax, 3 dr.; honey, 1 oz. Melt, and stir together, and then add syrup, 1 oz.

=Linctus, Caca′o.= _Syn._ LINCTUS CACAO, L.; CRÊME DE TRONCHIN, Fr. _Prep._ From cocoa-butter, 2 oz.; white sugar (in powder), syrup of capillaire, and syrup of tolu, of each 1 oz.; mix. Demulcent and pectoral; in coughs, sore throats, hoarseness, &c.

=Linctus, Common.= _Prep._ From oil of almonds and syrup of tolu, of each 1 oz.; powdered white sugar, 2 dr. As the last.

=Linctus, Cough.= _Syn._ PECTORAL LINCTUS; LINCTUS PECTORALIS, L. _Prep._ 1. (Dr Latham.) Compound ipecacuanha powder (Dover’s powder), 1/2 dr.; compound tragacanth powder, 2 dr.; syrup of tolu, confection of hips, and simple oxymel, of each 1 oz.——_Dose_, 1 teaspoonful, 3 or 4 times a day. “This linctus has been extensively used, as a remedy for coughs, in the West-end of London, having been found to be a safe and generally efficacious remedy.” (Redwood.) The preceding as well as the following are also useful preparations.

=Linctus, Demulcent.= _Syn._ LINCTUS DEMULCENS L.; LOOCH DE TRONCHIN, Fr. _Prep._ From oil of almonds, syrup of capillaire, manna and cassia pulp, of each 2 oz.; powdered gum tragacanth, 20 gr.; orange-flower water, 2 fl. oz. As the last. The above is the quantity for two days, which is as long as it will keep.

=Linctus of Egg.= _Syn._ LINCTUS OVI; LOHOCH OVI. _Prep._ Oil of almonds, 1/2 dr.; yolk of 1 egg; syrup of marshmallow, 1 oz. Mix.

=Linctus, Emol′lient.= _Syn._ OILY EMULSION; LOHOCH OLEOSUM, EMULSIO OLEOSA, L.; LOOCH HUILEUX, Fr. _Prep._ (P. Cod.) Oil of almonds, powdered gum, and orange-flower water, of each 4 dr.; syrup of marshmallow, 1 oz.; water, 3 fl. oz. or q. s.; for an emulsion. In troublesome coughs.

=Linctus, Expec′torant.= _Syn._ LINCTUS EXPECTORANS, LOHOCH E., L. _Prep._ 1. Oxymel of squills, confection of hips, syrup of marshmallow, and mucilage of gum Arabic (thick), equal parts. Demulcent and expectorant.

2. (Dr Copland.) Oil of almonds and syrup of lemons, of each 1 fl. oz.; powdered ipecacuanha 6 gr.; confections of hips, 1 oz.; compound powder of tragacanth, 3 dr.

3. (Zanetti.) Kermes mineral, 4 gr.; manna, 6 oz.; oil of almonds, syrup of squills, and syrup of senega, of each 2 dr. Laxative, demulcent, and expectorant. The above are useful in hoarseness, tickling coughs, sore throats, &c.

=Linctus, Green.= _Syn._ LINCTUS VIRIDE; LOHOCH VIRIDE. _Prep._ Pistachio nuts (or sweet almonds), no. 14; syrup of violets, 1 oz.; oil of almonds, 1/2 oz.; gum tragacanth, 15 gr.; tincture of saffron, 1 scruple; orange-flower water, 2 dr.; water, 4 oz. Mix.

=Linctus of Linseed.= (E. 1744.) _Syn._ LINCTUS LINI; LOHOCH LINI. _Prep._ Fresh drawn linseed oil, 1 oz.; syrup of tolu, 1 oz.; sulphur, 2 dr.; white sugar, 2 dr. Mix.

=Linctus of Manna.= (E. 1744.) _Syn._ LINCTUS MANNÆ; LOHOCH MANNÆ. _Prep._ Equal parts of manna, oil of almonds, and syrup of violets. Mix.

=Linctus of Naphthalin.= (Dupasquier) _Syn._ LINCTUS NAPHTHALINI; LOHOCH NAPHTHALINI. _Prep._ To one common lohoch add from 8 gr. to 30 gr. of naphthalin. The latter must be well triturated with the gum.——_Dose._ One teaspoonful, as an expectorant.

=Linctus, Pectoral.= _Syn._ FOX LUNGS; LINCTUS PECTORALIS, LOHOCH È PULMONE VULPIUM, L. _Prep._ From spermaceti and Spanish juice, of each 8 oz.; water, q. s. to soften the liquorice; make a thin electuary, and add of honey, 3 lbs.; oil of aniseed, 1 oz.; mix well. A popular and excellent demulcent in coughs. It formerly contained the herb fox lungs, but spermaceti is now substituted for that article.

=Linctus of Poppies.= (Th. Hosp.) _Syn._ LINCTUS PAPAVERIS. _Prep._ Compound tincture of camphor, syrup of poppies, and syrup of tolu, of each equal parts. Mix.——_Dose_, 1 fl. dr.

=Linctus of Spermaceti.= (E. 1744.) _Syn._ LINCTUS CETACEI; LOHOCH CETACEI. _Prep._ Spermaceti, 2 dr.; yolk of egg, q. s.; triturate, and add gradually oil of almonds, 1/2 oz.; syrup of tolu, 1 oz. Mix.

=Linctus of Syrup of White Poppies.= (P. C.) _Syn._ LINCTUS SYRUPI PAPAVERIS ALBI; LOHOCH SYRUPUS PAPAVERIS ALBI. _Prep._ White lohoch, 5 parts; syrup of poppies (P. C.), 1 part. Mix.

=Linctus, Turpentine.= _Syn._ LINCTUS STIMULANS, L. TEREBINTHINÆ, LOHOCH ANTHELMINTICUM, L. _Prep._ (Recamier.) Oil of turpentine, 2 dr.; honey of roses, 3 oz.; mix.——_Dose._ A teaspoonful, night and morning, followed by a draught of any weak liquid; in worms, more especially tape-worm.

=Linctus, White.= _Syn._ LINCTUS ALBUS, MISTURA ALBA, LOHOCH ALBUM, L.; LOOCH BLANC, Fr. _Prep._ (P. Cod.) Jordon almonds, 4-1/2 dr.; bitter almonds, 1/2 dr.; blanch them by steeping them in hot water and removing the skins; add of white sugar, 1/2 oz.; gum tragacanth, 20 gr.; beat to a smooth paste, and further add of oil of almonds and orange-flower water, of each 4 dr.; pure water, 4 fl. oz. A pleasant demulcent in tickling coughs.

=LIN′EN.= _Syn._ LINTEUM, L. Linen is a textile fabric made of the libre-fibres of the _Linum usitatissimum_, or common flax, a plant which from time immemorial has been cultivated for this purpose. It is remarkable for the smoothness and softness of its texture, and is hence highly esteemed in temperate climates as an elegant and agreeable article of clothing to be worn next the skin. Its fibres are better conductors of heat, more porous, and more attractive of moisture, than those of cotton, which render it less adapted for body linen in cold weather, as well as in hot weather and hot climates, than calico. The latter, however, lacks the luxurious softness and freshness of linen, whilst the peculiar twisted and jagged character of its fibres render it apt to excite irritation in extremely delicate skins. The common prejudice in favour of old linen and flax lint for dressing wounds is thus shown to have reason on its side, and, like many other vulgar prejudices, to be supported by the investigations of science.

_Identif._ Linen fabrics are commonly sophisticated with cotton, which is a much less costly and a more easily wrought material. Various plans have been proposed to detect this fraud, many of which are too complicated and difficult for practical purposes. The following commend themselves for their simplicity and ease of application:——

1. A small strip (a square inch, for instance) of the suspected cloth is immersed for 2 or 3 minutes in a boiling mixture of about equal parts of hydrate of potassium and water, contained in a vessel of silver, porcelain, or hard glass; after which it is taken out and pressed between the folds of white blotting paper or porous calico. By separating 8 or 10 threads in each direction, their colour may be readily seen. The deep yellow threads are LINEN, the white or pale yellow ones are COTTON.

2. A small strip of the cloth, after having been repeatedly washed with rain water, boiled in the water, and dried, is immersed for 1 to 2 minutes in sulphuric acid; it is then withdrawn, carefully pressed under water with the fingers, washed, immersed for a few seconds in ammonia, solution of carbonate of potassium, or solution of carbonate of sodium, again washed with water, and dried between filtering paper. By this treatment the cotton fibres are dissolved, while the linen fibres are merely rendered thinner and more translucent according to the duration of the experiment; after a short immersion, the cotton fibres appear transparent, while the linen fibres remain white and opaque.

3. Böttger recommends the linen stuffs to be dipped into an alcoholic solution of rosolic acid, then into a concentration solution of sodium carbonate, and finally washed with water. The linen fibre assumes a pink colour, whilst the cotton fibre remains unaltered.

4. (By the MICROSCOPE.) The indications afforded by both the previous tests, although quite visible to the naked eye, are rendered still more palpable by the use of a magnifying glass of small power, as the common pocket lens. Under a good microscope the presence of cotton in a linen tissue is very perceptible. The fibres of cotton present a distinctly flat and shrivelled appearance, not unlike that of a narrow, twisted ribbon, with only occasional joints; whilst those of flax are round, straight, and jointed. The fibres of cotton, after being exposed to the action of strong alkaline lyes, untwist themselves, contract in length, and assume a rounded form, but still continue distinct in appearance from the fibres of linen. The engraving represents a fibre of linen (1) and a fibre of cotton (2), as they appear when magnified 155 diameters. The difference between the two may be perceived, although less distinctly through a good Stanhope or Coddington lens, provided the object be well illuminated.

_Dyeing._ Linen and cotton, from the similarity of their behaviour with dye-stuffs, are treated in nearly the same manner. The affinity of their fibres for colouring matter is very much weaker than that of the fibres of silk and woollen. On this account they are dyed with greater difficulty than those substances, and the colours so imparted are, in general, less brilliant and permanent under similar conditions. Linen shows less disposition to take dyes than cotton. The yarn or cloth, after being scoured and bleached in the usual manner, requires to have an additional tendency given to it, by chemical means, to condense and retain the materials of the dye-bath in its pores. This is effected by steeping the goods in solutions (mordants) which have at once an affinity for both the fibres of the cloth and the colouring matter. A similar process is employed in dyeing most other substances; but with cotton and linen, attention to this point is essential to the permanency of the dye. These matters are more fully explained under the heads DYEING and MORDANT.

The following new process for bleaching linen, having been omitted from our article on “Bleaching” is inserted here:——

Mr Hodges’ process, which is known in Ireland as the “Chemico-Mechanical Process,” owing to the patentee turning to account the advantages derivable from the employment of mechanical contrivances driven by steam, combined with the introduction of a new method of obtaining the hitherto little used hypochlorite of magnesia, may be said to date from the discovery of the substance, known as _Kieserite_ (native sulphate of magnesia), which occurs as an essential constituent of the Abraumsalts of Stassfurth. For some time after the introduction of this substance into the market, it was considered of little value except for the production of Epsom salts; but Mr. Hodges, in the course of some investigations in bleaching jute, having had occasion to employ large quantities of hypochlorite of magnesia, it occurred to him that kieserite might be substituted for the more expensive crude sulphate of magnesia; and the importation into Ireland of the sample for this purpose was the first that was ever sent into that country for the manufacture of a bleaching liquor, or, indeed, for any other use. Mr. Hodges on experimenting with the kieserite, found that it not only supplied the place of the crude sulphate, but acted as a better precipitant for the lime of the bleaching powder, which is employed in the production of the hypochlorite of magnesia; and that it also produced a stronger and clearer solution. Without entering into a minute description of the process (which is at present successfully carried out in a factory erected for the purpose in the neighbourhood of Belfast), the following outline will be sufficient to show the nature of the methods adopted. The kieserite, which is imported from Germany in square blocks, on arriving at the works, is conveyed to a house, on the ground-floor of which it is stacked until required, when it is ground to a fine powder, and placed in barrels, is drawn up by means of a crane to a room at the top of the building, at one end of which is a row of three tanks furnished with water taps, agitators, and false bottoms. In one of the end tanks a definite quantity of the kieserite powder (varying according to its strength, is ascertained by analysis) is placed and dissolved in a given quantity of water, the solution being assisted by agitators, and on settling the clear liquor is siphoned over into the middle tank. In the third tank bleaching powder (hypochlorite of lime), varying in quantity according to the strength of the kieserite solution, is placed. The bleaching powder after being agitated with water is allowed to settle, and the clear solution is siphoned over into the middle tank containing the clear kieserite solution, the agitator being kept in motion, not only during the mixing of the liquids, but for some time after. The mixed liquids are then allowed to remain undisturbed all night, after which the clear hypochlorite of magnesia solution is siphoned into a large settling tank, which is situated in the room below. From this vessel it is conducted through wooden pipes (which are so contrived that they can be opened and cleansed at will), into a large cistern standing in the bleaching house. This cistern is fitted with a ball-cock, by which arrangement the liquid can be drawn off by a system of wooden pipes as required. The bleaching house in which the cistern is situated is fitted up in an original manner, and covers something more than an acre of ground; whilst the reeling-shed, which is the only part of the works our limits will permit us describe, is 240 feet long by 24 feet broad, and contains ten steeps and twelve reel boxes. Each box is provided with water, a solution of the bleaching agent, and steam pipes, and is capable of reeling at a time about 500 lbs. of yarn. Above the box is a line of rails or pillars. A travelling crane runs along the reels, and carries the reels from one box to another. Attached to this crane is a newly-invented hydraulic pump, by means of which the reels with the yarn on them can be lifted in a few seconds from one box to another.

After the yarn has been boiled, washed, and passed through the squeezers in the usual manner, it is put on to a wagon, in which it is carried, by means of a line of rails, down to the first reel box. Here it is placed on to the reels, which are made to revolve by means of steam; first in one direction and then in another, through a solution of carbonate of soda, previously heated by means of the steam-pipes before mentioned. The yarn having been sufficiently scalded and so saturated with soda, the reels to which it is attached are raised by the hydraulic pump out of the box, and the yarn allowed to drain for a few minutes, after which the travelling crane carries it on to the next box. Into this box the yarn is again lowered by the pump and made to revolve as before, but this time through a solution of the bleaching agent, which immediately re-acting on the carbonate of soda with which the yarn is charged, renders this bleaching agent free from the danger which attends the employment of chlorine, or the ordinary bleaching powder used in the older methods of bleaching. After the yarns have been brought to the desired shade in the solution of Hodges’ bleaching agent they are either removed as before to a new box, and there washed before being scoured, or they are thrown into one of the steeps filled with water for the night. These operations are repeated with weaker solutions in the remaining reel boxes, either once or twice according to the shade required.

Mr Hodges claims as the chief features of his invention that it consists, first, in the employment of a bleaching agent which has not hitherto been practically employed, and a cheap method for its production; second, in the preparation of the yarn prior to being submitted to the action of the bleaching agent, this preparation setting free not only the imprisoned chlorine of the hypochlorite, but also another powerful bleaching agent, oxygen; third, in new and improved machinery, by which the work of bleaching the yarn is greatly shortened; fourth, in doing away with the tedious and expensive operation of exposing the yarn on the grass; if this last were the only feature in Mr Hodges’ invention, the patentee would have greatly improved the process of bleaching, not only, however, does the new process supplant the old long and tedious one, but a great economy of time is additionally gained in other parts of the process, added to these advantages it is stated that a superior finish is given to the yarns, and that in consequence a much greater demand for them has arisen.

Mr Hodges contends that the absence of caustic lime from his new bleaching compound gives it great advantages over the old bleaching powder, particularly in its application to finely woven fabrics, such as muslins, &c. He also says that fabrics bleached by it receive an increased capacity for imbibing and retaining colouring matter, a fact of considerable importance to the dyer and calico-printer, as they are thus enabled to communicate to the fabrics tints which have heretofore been considered impossible. See KIESERITE.

The domestic management of linen may here receive a few moments’ attention. Fruit stains, iron-moulds, and other spots on linen, may, in general, be removed by applying to the part, previously washed clean, a weak solution of chlorine, chloride of lime, spirits of salts, oxalic acid, or salts of lemons, in warm water, and frequently by merely using a little lemon juice. When the stain is removed the part should be thoroughly rinsed in clear warm water (without soap) and dried. Recent iron-moulds or ink spots on starched linen, as the front of a shirt, may be conveniently removed by allowing a drop or two of melted tallow from a common candle to fall upon them before sending the articles to the laundress. The oxide of iron combines with the grease, and the two are washed out together. If the spot is not entirely removed the first time, the process should be repeated. Linen that has acquired a yellow or bad colour by careless washing may be restored to its former whiteness by working it well in water to which some strained solution of chloride of lime has been added, observing to well rinse it in clean water both before and after the immersion in the bleaching liquor. The attempt to bleach unwashed linen should be avoided, as also using the liquor too strong, as in that case the linen will be rendered rotten.

=LING.= The _Galus molua_ (Linn.), an inferior species of the cod-fish tribe, common in the Northern seas, and used as a coarse article of food by the poor.

=LIN′IMENT.= _Syn._ LINIMENTUM, L. A semifluid ointment, or soapy application to painful joints, swellings, burns, &c. The term is also occasionally extended to various spirituous and stimulating external applications. A preparation of a thinner consistence, but similarly employed, is called an ‘EMBROCATION,’ These terms are, however, frequently confounded together, and misapplied. Liniments are generally administered by friction with the hand or fingers, or with some substance (as a piece of flannel) capable of producing a certain amount of irritation of the skin. Sometimes a piece of linen rag dipped in them is simply laid on the part. In most cases in which liniments are found beneficial, the advantage obtained from them is attributable rather to the friction or local irritation than to any medicinal power in the preparation itself. The greater number of cerates and ointments may be converted into liniments by simply reducing their consistence with almond or olive oil, or oil of turpentine.

=Liniment, Ac′id.= _Syn._ LINIMENTUM ACIDUM, L. ACIDI SULPHURICI, L. _Prep._ 1. (Sir B. Brodie.) Salad oil, 3 oz.; oil of vitriol, 1 dr.; mix, then add of oil of turpentine, 1 oz., and agitate the whole well together. As a counter-irritant, in rheumatism, stiff joints, &c. It closely resembles the ‘GULLTONIAN EMBROCATION,’

2. (Hosp. F.) Olive oil, 3 oz.; oil of turpentine, 2 oz.; sulphuric acid, 1 fl. dr. An excellent alterative, stimulant, discutient, and counter-irritant, in chronic rheumatism, stiff joints, indolent tumours, and various chronic diseases of the skin.

=Liniment of Albumen.= (Dr Christison.) _Syn._ LINIMENTUM ALBUMINIS. _Prep._ Equal parts of white of egg and rectified spirit, agitated together. In excoriation from pressure.

=Liniment of Am′ber-oil.= _Syn._ LINIMENTUM SUCCINI, L. _Prep._ 1. From olive oil, 3 parts; oils of amber and cloves, of each 1 part. Resembles ‘ROCHE’S EMBROCATION,’

2. (Opiated; LINIMENTUM SUCCINI OPIATUM, L.) From rectified oil of amber and tincture of opium, of each 2 fl. oz.; lard, 1 oz. Anodyne, antispasmodic, and stimulant. A once popular remedy in cramp, stiff joints, &c.

=Liniment of Ammo′′nia.= _Syn._ AMMONIACAL LINIMENT, VOLATILE L., OIL AND HARTSHORN; LINIMENTUM AMMONIÆ (B. P., Ph. L. E. & D.), L. _Prep._ 1. (B. P.) Solution of ammonia, 1; olive oil, 3; mix.

2. (Ph. L. & E.) Liquor of ammonia (sp. gr. ·960), 1 fl. oz.; olive oil, 2 fl. oz.; shake them together until they are mixed.

3. (Ph. D.) To the last add of olive oil, 1 fl. oz. Stimulant and rubefacient. Used in rheumatism, lumbago, neuralgia, sore throat, spasms, bruises, &c. When the skin is irritable more oil should be added, or it should be diluted with a little water.

4. (Camphorated; LINIMENTUM AMMONIÆ CAMPHORATUM, EMBROCATIO AMM. CAMPHORATA, L.)——_a._ (Hosp. F.) Olive oil, 3 oz.; camphor, 1/2 oz.; dissolve by a gentle heat, and when cold, add of liquor of ammonia, 1 fl. oz.

_b._ Soap liniment, 2 oz.; olive oil and liquor of ammonia, of each 2 dr. As the last; more especially for sprains, bruises, chilblains, &c.

5. (Compound; Dr GRANVILLE’S COUNTER-IRRITANT OR ANTIDYNOUS LOTION; LINIMENTUM AMMONIÆ COMPOSITUM, L.——Ph. E.)——_a._ (STRONGER.) From liquor of ammonia (sp. gr. ·880), 5 fl. oz.; tincture of camphor, 2 fl. oz.; spirit of rosemary, 1 fl. oz.; mix. It should be kept in a well-stoppered bottle and in a cool situation.

_b._ (WEAKER.) Solution of ammonia (·880), 5 fl. oz.; tincture of camphor, 3 fl. oz.; spirit of rosemary, 2 fl. oz.

_Obs._ The above formulæ are nearly identical with the original ones of Dr Granville; the principal difference being in his ordering liquor of ammonia of the sp. gr. ·872, instead of ·880. They are counter-irritant, rubefacient, vesicant, and cauterising, according to the mode and length of their application. The milder lotion is sufficiently powerful to produce considerable rubefaction and irritation in from 1 to 5 or 6 minutes; vesication, in 8 or 10 minutes; and cauterisation, in 4 or 5 minutes longer. For the latter purpose the stronger lotion is generally employed. According to Dr Granville, these lotions are prompt and powerful remedies in rheumatism, lumbago, cramp, neuralgia, sprains, swollen and painful joints, headache, sore throat, and numerous other affections in which the use of a powerful counter-irritant has been recommended. They are ordered to be applied by means of a piece of linen, 6 or 7 times folded, or a piece of thick, coarse flannel wetted with the lotion, the whole being covered with a thick towel, and firmly pressed against the part with the hand. The stronger lotion is only intended to be employed in apoplexy, and to produce cauterisation. See COUNTER-IRRITANTS.

6. (From SESQUICARBONATE OF AMMONIA;——LINIMENTUM AMMONIÆ SESQUICARBONATIS——Ph. L.) Solution of sesquicarbonate of ammonia, 1 fl. oz.; olive oil, 3 fl. oz.; shake them together until mixed. This preparation resembles ordinary liniment of ammonia in its general properties, but it is much less active, owing to the alkali being carbonated. It is the ‘oil and hartshorn’ and the ‘volatile liniment’ of the shops.

7. (WITH TURPENTINE.) (Dr Copland.) _Syn._ LINIMENTUM AMMONIÆ CUM TEREBINTHINA. _Prep._ Liniment of ammonia, 1-1/4 fl. oz.; oil of turpentine, 1/2 fl. oz.; mix.

=Liniment, An′odyne.= See LINIMENTS OF BELLADONNA, MORPHIA, OPIUM, SOAP, &c.

=Liniment, Antispasmod′ic.= _Syn_. LINIMENTUM ANTISPASMODICUM, L. CAJEPUTI COMPOSITUM, L. _Prep._ (Hufeland.) Oils of cajeput and mint, of each 1 part; tincture of opium, 3 parts; compound camphor liniment, 24 parts. Anodyne, stimulant, and rubefacient.

=Liniment, Arceus’s.= Compound elemi ointment.

=Liniment of Arnica.= _Syn._ ARNICA OPODELDOC, LINIMENTUM ARNICÆ. _Prep._ Dissolve by heat Castile soap, 4 parts, and camphor, 1 part, in rectified spirit, 10 parts. Add tincture of arnica, 5 parts.

=Liniment of Belladon′na.= _Syn._ LINIMENTUM BELLADONNÆ, B. P. L. _Prep._ 1. (B. P.) Prepared the same as LINIMENTUM ACONITII. A fluid ounce is equal to a solid ounce. Prescribed with equal parts of soap liniment, or compound camphor liniment, and is an excellent topical application for neuralgic pain.

2. Extract of belladonna, 1 dr.; oil of almonds, 2 oz.; lime water, 4 fl. oz. In eczema, and some other cutaneous affections, to allay irritation, &c.

3. (Cutan. Hosp.) Extract of belladonna, 4 dr.; glycerine, 1 oz.; soap liniment, 6 oz. As the last.

4. (Guy’s Hosp.) Extract of belladonna 1 oz.; soap liniment, 8 fl. oz.

5. (Phœbus.) Extract of belladonna, 40 gr.; rectified ether, 1 dr.; cherry-laurel water, 2 fl. oz. As a friction to the abdomen in lead colic.

_Obs._ The above are reputed excellent stimulants, anodynes, antispasmodics, and resolvents, in various diseases, as rheumatism, neuralgia, painful affections of the skin and joints, tumours, &c. &c.

=Liniment of Belladonna and Chloroform.= (Mr Squire.) _Syn._ LINIMENTUM BELLADONNÆ ET CHLOROFORMI. _Prep._ Belladonna liniment, 7 fl. dr.; belladonna chloroform (made by percolating the root with chloroform) 1 fl. dr.; sprinkled on piline and applied to the loins, excellent in lumbago.

=Liniment of Borax.= (Swediaur). _Syn._ LINIMENTUM BORACIS. _Prep._ Borax, 2 dr.; tincture of myrrh, 1 oz., distilled water, 1 oz.; honey of roses, 2 oz. Mix.

=Liniment of Caj′eput Oil.= _Syn._ LINIMENTUM OLEI CAJEPUTI, L. _Prep._ 1. (Dr Copland.) Compound camphor liniment and soap liniment, of each 1-1/2 fl. oz.; oil of cajeput, 1 fl. oz.

2. (Dr Williams.) Oil of cajeput, 1/2 fl. dr.; castor oil, 1 fl. dr.; olive oil, 4-1/2 fl. dr. A warm, antispasmodic, diffusible stimulant and rubefacient; in spasmodic asthma, colic, chronic rheumatism, spasms, chest affections, &c. See ANTISPASMODIC L. (_above_).

=Linimentum Calcis.= (B. P.) Solution of lime, 1; olive oil, 1; mix. The best liniment for burns and scalds.

=Liniment of Cam′phor.= _Syn._ CAMPHORATED OIL, CAMPHOR EMBROCATION; LINIMENTUM CAMPHORÆ (B. P., Ph. L. E. & D.), OLEUM CAMPHORATUM, L. _Prep._ 1. (B. P.) Camphor, 1; olive oil, 4; dissolve.

2. (Ph. L. & E.) Camphor, 1 oz.; olive oil, 4 fl. oz.; gently heat the oil, add the camphor (cut small), and agitate until dissolved. The Dublin College orders only 1/2 the above camphor. Stimulant, anodyne, and resolvent; in sprains, bruises, rheumatic pains, glandular enlargements, &c.

3. (Compound; LINIMENTUM CAMPHORÆ COMPOSITUM——B. P., Ph. L. & D.)——_a._ (B. P.) Camphor, 5; English oil of lavender, 1/4; strong solution of ammonia, 10; rectified spirit, 20. Dissolve the oil and camphor in the spirit and gradually add the ammonia.

_b._ (Ph. L.) Camphor, 2-1/2 oz.; oil of lavender, 1 fl. dr.; rectified spirit, 17 fl. oz.; dissolve, then add of stronger liquor of ammonia, 3 fl. oz., and shake them together until they are mixed.

_c._ (Ph. L. 1836.) Liquor of ammonia, 7-1/2 fl. oz.; spirit of lavender, 1 pint; distil off 1 pint, and dissolve in it camphor, 2-1/2 oz. The formula of the Ph. D. 1826 was nearly similar.

_d._ (Wholesale.) Camphor (clean), 21 oz.; English oil of lavender, 3-3/4 oz.; liquor of ammonia, 2-3/4 lbs.; rectified spirit, 7 pints; mix, close the vessel, and agitate occasionally, until the camphor is dissolved. Powerfully stimulant and rubefacient. It closely resembles, and is now almost universally sold for, Ward’s ‘Essence for the Headache.’

_e._ (Ethereal.) _Syn._ LINIMENTUM CAMPHORÆ ETHEREUM. _Prep._ Camphor, 1 dr.; ether, 1 dr.; oil of vipers, 2 dr. Mix.

=Liniment of Canthar′ides.= _Syn._ LINIMENT OF SPANISH FLIES; LINIMENTUM LYTTÆ, LIN. CANTHARIDIS (Ph. D. & U. S.), L. _Prep._ 1. (Dr Collier.) Tincture of cantharides and soap liniment, equal parts.

2. (Ph. D.) Cantharides (in fine powder), 3 oz.; olive oil, 12 fl. oz.; digest for 3 hours over a waterbath, and strain through flannel, with expression.

3. (Ph. U. S.) Spanish flies, 1 oz.; oil of turpentine, 8 fl. oz.; proceed as last. The above are irritant and rubefacient; but should be used cautiously, lest they produce strangury.

=Liniment of Capsicum.= 1. (Dr Copland.) _Syn._ LINIMENTUM CAPSICI. _Prep._ Compound camphor liniment, 1 fl. oz.; volatile liniment, 1 fl. oz.; tincture of capsicum, 3 fl. oz.; mix.

2. (Dr Turnbull.) Capsicums, 1 oz.; rectified spirit, 3 fl. oz. Macerate 7 days, and strain for use.

=Liniment of Colchicum.= (Ear Infirmary.) _Syn._ LINIMENTUM COLCHICI. _Prep._ Soap liniment, 1 fl. oz.; wine of colchicum seed, 1/2 fl. oz.; mix.

=Liniment of Colocynth.= (Heim). _Syn._ LINIMENTUM COLOCYNTHIDIS. _Prep._ Tincture of colocynth, 1/2 fl. oz.; castor oil, 1-1/2 oz.

=Liniment of Chlo′′ride of Lime.= _Syn._ LINIMENTUM CALCIS CHLORINATÆ, L. _Prep._ 1. Chloride of lime, 1 dr.; water (added gradually), 3 fl. oz.; triturate together in a glass mortar for 10 minutes, pour off the liquid portion, and add of oil of almonds 2 fl. oz.

2. (Kopp.) Solution of chloride of lime (ordinary), 1 part; olive oil, 2 parts.

3. (Waller.) Chloride of lime (in fine powder), 1 part; soft soap, 2 parts; soft water, q. s. to make a liniment.

_Obs._ The above are cleanly and excellent applications in itch, scald head, herpes, lepra, foul ulcers, &c.

=Liniment of Chlo′′roform.= _Syn._ LINIMENTUM CHLOROFORMI, B. P. _Prep._ 1. (B. P.) Chloroform, 1; liniment of camphor, 1; mix. The oil in the camphor liniment prevents the evaporation of the chloroform. Stimulating on application to a tender skin.

2. Chloroform, 1 fl. dr.; almond oil, 7 fl. dr.; mix in a phial, and agitate it until the two unite.

3. (Tuson.) Chloroform, 1 fl. dr.; soap liniment, 2 fl. oz.; as the last. Used as an application in neuralgic pains, rheumatism, &c.

=Liniment of Cod-liver Oil.= _Syn._ LINIMENTUM OLEI MORRHUÆ, L. O. JACORIS ASELLI, L. _Prep._ (Dr Brach.) Cod-liver oil, 2 fl. oz.; liquor of ammonia, 1 fl. oz.; mix. Resolvent, dispersive; applied to glandular tumours, scrofulous enlargements, &c.

=Liniment of Cro′ton Oil.= _Syn._ LINIMENTUM CROTONIS (B. P., Ph. D.), L. OLEI CROTONIS, L. O. TIGLII, L. _Prep._ 1. (B. P.) Croton oil, 1; oil of cajeput, 3-1/2; rectified spirit, 3-1/2; mix.

2. (Ph. D.) Croton oil, 1 fl. oz.; oil of turpentine, 7 fl. oz.; mix by agitation.

3. (J. Allen.) Croton oil and liquor of potassa, of each, 1 fl. dr.; agitate until mixed, then add of rose water, 2 fl. oz.

4 (Pereira.) Croton oil, 1 part; olive oil, 5 parts.

_Obs._ The above are used as counter-irritants; in rheumatism, neuralgia, bronchial and pulmonary affections, &c. When rubbed on the skin, redness, and a pustular eruption ensue, and in general the bowels are acted on.

=Liniment, Diuretic.= _Syn._ LINIMENTUM DIURETICUM, L. _Prep._ 1. (Dr Calini.) Squills (in fine powder), 1 dr.; gastric juice of a calf, 2 oz.; mix.

2. (Dr Christison.) Soap liniment, tincture of foxglove, and tincture of squills, equal parts. In dropsies; rubbed over the abdomen or loins twice or thrice a day.

=Liniment, Emol′lient.= _Syn._ LINIMENTUM ALBUM, L. EMOLLIENS, L. _Prep._ From camphor, 1 dr.; Peruvian balsam, 1/2 dr.; oil of almonds, 1 fl. oz.; dissolve by heat, add of glycerin, 1/2 fl. oz., agitate well, and, when cold, further add of oil of nutmeg, 15 drops. Excellent for chapped hands, lips, nipples, &c.

=Liniment of Foxglove.= (Dr Royle.) _Syn._ LINIMENTUM DIGITALIS. _Prep._ Infusion of digitalis, 2 fl. oz.; water of ammonia, 2 fl. dr.; oil of poppy seed, 4 fl. dr.; mix. To be rubbed on the abdomen 3 or 4 times a day.

=Liniment of Gar′lic.= _Syn._ LINIMENTUM ALII, L. _Prep._ From juice of garlic, 2 parts; olive oil, 3 parts; mix. In hooping-cough, infantile convulsions, &c.

=Liniment of Gin′ger.= _Syn._ LINIMENTUM ZINGIBERIS, L. _Prep._ (Dr Turnbull.) Ginger, 1 part; rectified spirit, 2 parts; make a tincture or essence. For short-sightedness. A few drops are occasionally rubbed on the forehead for 8 or 10 minutes at a time. How this tincture came to be called a liniment we are at a loss to determine.

=Liniment of Glycerin.= (Mr Startin.) _Syn._ LINIMENTUM GLYCERINI. _Prep._ Soap liniment, 3 oz.; glycerin, 1 oz.; extract of belladonna, 1 oz.; mix. For gouty, rheumatic, and neuralgic pains. A little veratrine is sometimes added.

=Liniment, Green.= (Dr Campbell.) _Syn._ LINIMENTUM VIRIDE. Camphor, 1 oz.; olive oil, 6 oz.; extract of hemlock, 1 oz.; spirit of ammonia, 2 oz. Mix.

=Liniment of Hellebore.= (Dornbleuth.) _Syn._ LINIMENTUM HELLEBORI. _Prep._ Soft soap, 4 oz.; hellebore powder, 2 oz.; hot water, q. s.

=Liniment, Hunga′′rian.= _Syn._ LINIMENTUM HUNGARICUM, L. _Prep._ (Soubeiran.) Powdered cantharides and sliced garlic, of each 1 dr.; camphor, bruised mustard seed, and black pepper, of each 4 dr.; strong vinegar, 6 fl. oz.; rectified spirit, 12 fl. oz.; macerate a week, and filter. An excellent rubefacient and counter-irritant.

=Liniment of Hydrochlo′′ric Acid.= _Syn._ LINIMENTUM MURIATICUM, L. ACIDI MURIATICI, L. A. HYDROCHLORICI, L. _Prep._ 1. (Hosp. F.) Olive oil, 2 oz.; white wax, 2 dr.; dissolve by a gentle heat, add of balsam of Peru, 1 dr.; hydrochloric acid, 2 dr.; mix well. An excellent application to chilblains before they break.

2. (W. Cooley.) Olive oil, 1/4 pint; white spermaceti (pure) and camphor, of each 1/2 oz.; mix with heat, add of hydrochloric acid, 1/2 fl. oz., and proceed as before. Equal to the last, and cheaper. This was extensively employed among the seamen of the Royal Navy by Mr Cooley with uniform success.

=Liniment of I′odide of Potas′sium.= _Syn._ LINIMENTUM IODURETUM GELATINOSUM, L. GELÉE POUR LE GOITRE, Fr. _Prep._ (Foy.) Iodide of potassium, 4 dr.; proof spirit, 2 oz.; dissolve, and add the liquid to a solution of curd soap, 6 dr., in proof spirit, 2 oz., both being at the time gently warmed; lastly, aromatise with rose or neroli, pour it into wide-mouthed bottles, and keep them closely corked. In goitre, &c.

=Liniment of Iodide of Sulphur.= (Prof. E. Wilson.) _Syn._ LINIMENTUM SULPHURIS IODIDI. _Prep._ Iodide of sulphur, 30 gr.; olive oil, 1 fl. dr.; triturate together.

=Liniment of I′odine.= _Syn._ LINIMENTUM IODI (B. P.); IODURETTED LINIMENT; LINIMENTUM IODINII, L. IODURETUM, L. _Prep._ 1. (B. P.) Iodine, 5; iodide of potassium, 2; camphor, 1; rectified spirit, 40; dissolve.

2. (Cutan. Hosp.) Compound tincture of iodine and laudanum, equal parts.

3. (Dr Copland.) Soap liniment, 1 oz.; iodine, 8 to 10 gr.

4. (Guibourt.) Iodide of potassium, 1 dr.; water, 1 fl. dr.; dissolve, and add to it white soap (in shavings) and oil of almonds, of each 10 dr., previously melted together. Some perfume may be added. In scrofula, glandular enlargements, rheumatism, &c.

=Liniment of Ipecacuanha.= (Dr Neligan.) _Syn._ LINIMENTUM IPECACUANHÆ. _Prep._ Ipecacuanha in fine powder, 4 dr.; lard, 2 dr.; olive oil, 1-1/2 fl. oz.

=Liniment of Juniper.= (Dr Sully.) _Syn._ LINIMENTUM JUNIPERI. _Prep._ Oil of juniper, 1-1/2 oz.; lard, 2 oz.; oil of aniseed, 6 drops. For scald-head.

=Liniment of Labdanum.= (Quincy.) _Syn._ LINIMENTUM LABDANI; LINIMENTUM CRINISCANI. _Prep._ Labdanum, 6 dr.; bear’s grease, 2 oz.; honey, 1/2 oz.; powdered southernwood, 3 dr.; oil of nutmeg, 1 dr.; balsam of Peru, 2 dr.; mix. To restore the hair.

=Liniment of Lead.= _Syn._ LINIMENTUM PLUMBI, L. _Prep._ (Gaozey.) Acetate of lead, 40 gr.; soft water, 12 fl. oz.; olive oil, 6 oz.; mix, and agitate well. Astringent and refrigerant. Useful in excoriations, especially when accompanied with inflammation.

=Liniment of Lime.= _Syn._ LINIMENT FOR BURNS, CARRON OIL; LINIMENTUM CALCIS (Ph. L. E. & D.), L. AQUÆ CALCIS, OLEUM LINI CUM CALCIS, L. _Prep._ 1. From olive oil (linseed oil——Ph. E.) and lime water, equal parts, shaken together until they are mixed. Very useful in burns and scalds.

2. (Compound; LINIMENTUM CALCIS COMPOSITUM, L.)——_a._ (Camphorated——W. Cooley.) Camphor liniment and lime water, equal parts.

_b._ (Opiated——W. Cooley.) Lime water and camphor liniment, of each 1 oz.; extract of opium, 5 gr.; mix. Both are used as anodynes to allay pain and irritation in severe burns, chilblains, &c., for which purpose they are excellent. All the above liniments with lime water should be used as soon as possible after being prepared, as the ingredients separate by keeping.

=Liniment of Mercury.= _Syn._ MERCURIAL LINIMENT; LINIMENTUM HYDRARGYRI (B. P., Ph. L.), LIN. H. COMPOSITUM (Ph. L. 1836), L. _Prep._ 1. (B. P.) Ointment of mercury, 1; solution of ammonia, 1; liniment of camphor, 1. Melt the ointment in the liniment, add the ammonia, and shake them together.

2. (Ph. L.) Camphor, 1 oz.; spirit of wine, 1 fl. dr.; sprinkle the latter on the former, powder, add of lard and mercurial ointment (stronger), of each 4 oz.; rub them well together, then gradually add of liquor of ammonia, 4 fl. oz.; and mix well. Stimulant and discutient. It resembles mercurial ointment in its effects; but though milder in its operation, it more quickly produces salivation.

=Liniment of Mor′phia.= _Syn._ LINIMENTUM MORPHIÆ, L. _Prep._ (W. Cooley.) Pure morphia, 3 gr.; put it into a warm mortar, add very gradually, of oil of almonds (warm), 1 fl. oz., and triturate until the morphia is dissolved, then add of camphor liniment, 1 oz. An excellent topical anodyne and antispasmodic, which often allays pain when other means have failed.

=Liniment of Mus′tard.= _Syn._ LINIMENTUM SINAPIS, L. _Prep._ 1. Flour of mustard (best), 1 oz.; water, tepid, 2 fl. oz.; mix, and add of glycerin, liquor of ammonia, and olive oil, of each 1 fl. oz.

2. (Béral.) Carbonate of ammonia (in fine powder), 1 part; camphor (in powder), 2 parts; oil of lavender, 4 parts; tincture of mustard, 6 parts; mix, dissolve by agitation, add of simple liniment (warm), 56 parts, and again agitate until the whole is perfectly incorporated.

3. Black mustard seed (ground in pepper-mill or otherwise well bruised), 1/4 lb.; oil of turpentine, 1 pint; digest, express the liquid, filter, and dissolve it in camphor, 1/2 lb. Stimulant and rubefacient. A popular and useful remedy in rheumatic pains, lumbago, colic, chilblains, &c. The last is a close imitation of Whitehead’s ‘Essence of Mustard.’

4. (LIN. OLEI VOLATILIS SINAPIS.)——_a._ From volatile oil of black mustard seed, 1/2 dr.; oil of almonds, 1 fl. oz. As a rubefacient.

_b._ From volatile oil, 1 part; alcohol (sp. gr. ·815), 1 to 2 parts. As a vesicant.

=Liniment of Mustard (Compound).= LINIMENTUM SINAPIS COMPOSITUM (B. P.). Oil of mustard, 1 dr.; ethereal extract of mezereon, 40 gr.; camphor, 2 dr.; castor oil, 5 dr.; rectified spirit, 32 dr.; dissolve.

=Liniment, Narcotic.= (P. Codex.) _Syn._ LINIMENT CALMANT; LINIMENTUM NARCOTICUM. _Prep._ Anodyne balsam, 8 parts; compound wine of opium, cold cream, of each 1 part. Mix.

=Liniment of Ni′trate of Mercury.= _Syn._ CITRINE LINIMENT; LINIMENTUM HYDRARGYRI NITRATIS, L. _Prep._ (Sir H. Halford.) Ointment of nitrate of mercury and olive oil, equal parts, triturated together in a glass mortar, or mixed by a gentle heat. This liniment is stimulant, discutient, and alterative, and in its general properties resembles the ointment of the same name. For most purposes the quantity of oil should be at least doubled.

=Liniment of Nux Vom′ica.= _Syn._ LINIMENTUM NUCIS VOMICÆ, L. _Prep._ (Magendie.) Tincture of nux vomica, 1 fl. oz.; liquor of ammonia, 2 fl. dr.; mix. As a stimulating application to paralysed limbs. The addition of 1/2 fl. dr. each of glycerin and salad oil renders it an excellent application in chronic rheumatism and neuralgia.

=Liniment of Oil of Ergot.= _Syn._ LINIMENTUM OLEI ERGOTÆ. _Prep._ Oil of ergot, 1 dr.; oil of almonds, or sulphuric ether, 3 dr.; mix.

=Liniment of O′pium.= _Syn._ ANODYNE LINIMENT; LINIMENTUM OPII (B. P., Ph. L. & E.), L. OPII or L. ANODYNUM (Ph. D.), L. SAPONIS CUM OPIO, L. _Prep._ 1. (B. P.) Tincture of opium, 1; liniment of soap, 1; mix.

2. Tincture of opium, 2 fl. oz.; soap liniment, 6 fl. oz.; mix.

3. (Ph. E.) Castile soap, 6 oz.; opium, 1-1/2 oz.; rectified spirit, 1 quart; digest for three days, then filter, add of camphor, 3 oz., oil of rosemary, 6 fl. dr., and agitate briskly.

4. (Ph. D.) Soap liniment and tincture of opium, equal parts.

5. (Wholesale.) Soft soap, 1-1/4 lb.; powdered opium and camphor, of each 1/4 lb.; rectified spirit, 1 gall.; digest a week.

_Obs._ This preparation is an excellent anodyne in local pains, rheumatism, neuralgia, sprains, &c.

=Liniment of Phos′phorus.= _Syn._ LINIMENTUM PHOSPHORATUM, L. _Prep._ (Augustin.) Phosphorus, 6 gr.; camphor, 12 gr.; oil of almonds, 1 oz.; dissolve by heat; when cold, decant the clear portion, and add of strongest liquor of ammonia 10 drops. A useful friction in gout, chronic rheumatism, certain obstinate cutaneous affections, &c.

=Liniment de Rosen.= (P. C.) _Prep._ Oil of mace, 4 parts; oil of cloves, 4 parts; oil of juniper, 9 parts. Mix.

=Liniment, Sim′ple.= _Syn._ LINIMENTUM SIMPLEX (Ph. E.), L. _Prep._ (Ph. E.) White wax, 1 oz.; olive oil, 4 fl. oz.; melt together, and stir the mixture until it is cold. Emollient; resembles spermaceti ointment in all except its consistence.

=Liniment of Soap.= _Syn._ OPODELDOC, CAMPHORATED TINCTURE OF SOAP, BALSAM OF S.; LINIMENTUM SAPONIS (B. P., Ph. L. E. & D.) L. SAPONACEUM, TINCTURA SAPONIS CAMPHORATA, BALSAMUM SAPONIS, L. _Prep._ 1. (B. P.) Hard soap (cut small), 2-1/2 oz.; camphor, 1-1/4 oz.; English oil of rosemary, 3 dr.; rectified spirit, 18 oz.; distilled water, 2 oz.; mix the water and spirit, add the other ingredients, digest at a temperature not exceeding 70° Fahr., agitating occasionally for seven days, and filter.

2. (Ph. L.) Castile soap (cut small), 2-1/2 oz.; camphor (small), 10 dr.; spirit of rosemary, 18 fl. oz.; water, 2 fl. oz.; digest with frequent agitation until the solid substances are dissolved.

3. (Ph. E.) Castile soap, 5 oz.; camphor, 2-1/2 oz.; oil of rosemary, 6 fl. dr.; rectified spirit, 1 quart.

4. (Ph. D.) Castile soap (in powder), 2 oz.; camphor, 1 oz.; proof spirit, 16 fl. oz.

5. (LINIMENT SAVONNEAU——P. Cod.) Tincture of soap (P. Cod.) and rectified spirit (·863 or 41 o. p.), of each 8 parts; olive oil, 1 part.

_Obs._ This article, prepared according to the directions of the Pharmacopœia, from ‘soap made of olive oil and soda’ (Castile soap), is apt to gelatinise in cold weather, and to deposit crystals of elaidate and stearate of lime. This may be avoided, when expense is not an objection, by first well drying the soap, employing a spirit of at least 85%, and keeping the preparation in well-closed bottles. A cheaper and better plan is to substitute the ‘soft soap’ of the Ph. L. (‘soap made with olive oil and potassa’) for the Castile soap ordered by the College. The soft soap of commerce imparts to the liniment an unpleasant smell. The following formula, one of those commonly adopted by the wholesale druggists, produces a very good article, though much weaker than that of the Pharmacopœia.

6. (Wholesale.) Camphor (cut small), 1-1/2 lb.; soft soap, 7 lbs.; oil of rosemary, 3 fl. oz.; rectified spirit of wine and water, of each 3-1/2 galls.; digest with occasional agitation for a week, and filter. This is the ‘opodeldoc’ or ‘soap liniment’ of the shops.

_Uses._ Soap liniment is stimulant, discutient, and lubricating, and is a popular remedy in rheumatism, local pains, swellings, bruises, sprains, &c.

7. (With Opium.) See LINIMENT OF OPIUM.

8. (Sulphuretted; LINIMENTUM SAPONIS SULPHURETUM, L. SULPHURO-SAPONACEUM—— Jadelot, L.) Sulphuret of potassium, 3 oz.; soap, 12 oz.; water, q. s.; melt together, and add of olive oil, 12 oz.; oil of origanum, 1 fl. dr.; mix well. An excellent remedy for the itch, and some allied skin diseases.

=Liniment of Strychnia.= (Dr Neligan.) _Syn._ LINIMENTUM STRYCHNIÆ. Strychnia, 30 gr.; olive oil, 1-1/2 fl. oz. Ten drops to be rubbed over the temples in amaurosis.

=Liniment of Sul′phide of Carbon.= _Syn._ LINIMENTUM CARBONIS SULPHURETI, L. _Prep._ 1. From bisulphide of carbon, 1 dr.; camphorated oil, 1 oz.; mix.

2. (Lampadius.) Camphor, 2 dr.; bisulphuret of carbon, 4 fl. dr.; dissolve, and add of rectified spirit, 1 fl. oz. In rheumatism, gouty nodes, &c.

=Liniment of Sulphu′ric Acid.= See LINIMENT, ACID.

=Liniment, Tripharm′ic.= _Syn._ LINIMENTUM TRIPHARMICUM (Ph. L. 1746), L. _Prep._ Take of lead plaster and olive oil, of each 4 oz.; melt, add of strong vinegar, 1 fl. oz., and stir until cold. Cooling and desiccative; in excoriations, burns, &c.

=Liniment of Tur′pentine.= _Syn._ KENTISH’S LINIMENT; LINIMENTUM TEREBINTHINÆ (B. P., Ph. L. & D.), L. TEREBINTHINATUM (Ph. E.), L. _Prep._ 1. (B. P.) Oil of turpentine, 16; camphor, 1; soft soap, 2; dissolve the camphor in the turpentine, then add the soap, and rub till thoroughly mixed.

2. (Ph. L.) Soft soap, 2 oz.; camphor, 1 oz.; oil of turpentine, 10 fl. oz.; shake them together until mixed. Stimulant; in lumbago, cholera, colic, &c.

3. (Ph. L. 1824.) Resin cerate, 6 oz.; oil of turpentine, 4 fl. oz.; mix. An excellent application to burns.

4. (Ph. E.) Resin ointment, 4 oz.; camphor, 4 dr.; dissolve by a gentle heat, and stir in oil of turpentine, 5 fl. oz.

5. (Ph. D.) Oil of turpentine, 5 fl. oz.; resin ointment, 8 oz.; mix by a gentle heat. This forms Dr Kentish’s celebrated application to burns and scalds. The parts are first bathed with warm oil of turpentine or brandy, and then covered with pledgets of lint, smeared with the liniment.

6. (Compound——_a._ B. LINIMENTUM TEREBINTHINÆ ACETICUM.) Oil of turpentine, 1; acetic acid, 1; liniment of camphor, 1; mix.

_b._ (LINIMENTUM TEREBINTHINÆ COMPOSITUM, L.) Acetic: ST JOHN LONG’S LINIMENT; (LINIMENTUM TEREBINTHINÆ ACETICUM, L.) Oil of turpentine, 3 oz.; rose water, 2-1/2 fl. oz.; acetic acid, 5 dr.; oil of lemons, 1 dr.; yolk of egg, 1; make an emulsion. As a counter-irritant in phthisis.

_c._ (Ammoniated——Debreyne.) Lard, 3 oz.; melt, and add, of oil of turpentine and olive oil, of each 1 oz.; when cold, further add of camphorated spirit, 4 fl. dr.; liquor of ammonia, 1 fl. dr. In sciatica, lumbago, &c.

_d._ (Opiated——Recamier.) Oil of turpentine, 1 fl. oz.; oil of chamomile, 2 fl. oz.; tincture of opium, 1 fl. dr. In neuralgia, &c.

_e._ (Sulphuric——Ph. Castr. Ruthena.) Oil of turpentine, 2 oz.; olive oil, 5 oz.; mix, and add of dilute sulphuric acid, 1-1/2 dr. See ACID LINIMENT.

=Liniment of Vera′trine.= _Syn._ LINIMENTUM VERATRIÆ, L. _Prep._ (Brande.) Veratrine, 8 gr.; alcohol, 1/2 fl. oz.; dissolve, and add of soap liniment, 1/2 fl. oz. In neuralgic and rheumatic pains, gout, &c.

=Liniment of Ver′digris.= _Syn._ OXYMEL OF VERDIGRIS; LINIMENTUM ÆRUGINIS (Ph. L.), OXYMEL ÆRUGINIS (Ph. L. 1738), OXYMEL CUPRI SUBACETATIS (Ph. D. 1826), L. _Prep._ (Ph. L.) Verdigris (in powder), 1 oz.; vinegar, 7 fl. oz.; dissolve, filter, through linen, add of honey, 14 oz., and evaporate to a proper consistence.

_Obs._ This preparation is wrongly named a ‘liniment.’ The College, after ‘beating about the bush’ for nearly a century, found a right name for it in 1788; but, as in many other cases, soon abandoned it for another less appropriate.

Oxymel of verdigris is stimulant, detergent, and escharotic. It is applied to indolent ulcers, especially of the throat, by means of a camel-hair pencil; and, diluted with water, it is used as a gargle. Care must be taken to avoid swallowing it, as it occasions vomiting and excessive purging.

=Liniment, Ver′mifuge.= Syn. LINIMENTUM ANTHELMINTICUM, L. VERMIFUGUM, L. _Prep._ Castor oil, 1 oz.; essential oils of wormwood and tansy, of each 1/2 oz.; Dr Peschier’s ethereal tincture of pennyroyal buds, 20 drops; mix. Employed in frictions on the abdomen in cases of worms in children. Its activity may be still further increased by the addition of a little garlic juice. (‘Journ. de Méd.’) An excellent medicine.

=Liniment, Vesicating.= (Dr Montgomery.) _Syn._ LINIMENTUM VESICANS. For children. Prep. Compound camphor liniment, 4 fl. dr.; oil of turpentine, 2 fl. dr. To produce immediate vesication in adults. Mix one part of the strongest liquor ammoniæ, with two of olive oil, and apply six drops on spongio-piline for ten minutes.

=Liniment, Ware’s.= _Prep._ From camphor liniment, 1 oz.; solution of carbonate of potassa, 1 dr. In amaurosis.

=Liniment, White’s.= The old name for spermaceti ointment.

=Liniment, White.= _Syn._ LINIMENTUM ALBUM. _Prep._ Rectified oil of turpentine, 2 oz.; solution of ammonia, 2 oz.; soap liniment, 3 oz.; spirit of rosemary, 1 oz. Mix in the above order, and gradually add with continual agitation, distilled vinegar, 8 oz. For chapped hands.

=Liniment, Wilkinson’s.= _Prep._ (Phœbus.) Prepared chalk, 20 gr.; sulphur, lard, and tar, of each 1/2 oz.; mix, and add of Boyle’s fuming liquor, 10 or 15 drops. In certain chronic skin diseases, neuralgia, &c.

=Linimentum Aconiti.= (B. P.) Aconite root, in powder, 20; camphor, 1; rectified spirit, to percolate, 30. Moisten the root for 3 days, then pack in a percolator, and pour sufficient rectified spirit upon it to produce with the camphor 20.

Strength, 1 in 1. Applied with a camel-hair pencil, alone or mixed in equal proportions, with a soap liniment or compound camphor liniment, and rubbed on the part. Seven parts of this, and 1 part of chloroformum belladonna, and sprinkled thinly on impermeable piline, is the best application for neuralgia or lumbago.

=Linimentum Potassii Iodidi cum Sapone.= (B. P.) Hard soap, in powder, 1-1/2; iodide of potassium, 1-1/2; glycerin, 1; oil of lemon, 1/8; water, 1. Dissolve the soap in 7 of water by heat of a water bath; dissolve the iodide of potassium in the remainder of the water, and mix by trituration the two solutions, and when cold add the oil of lemon, and mix thoroughly.

=LINOLEIC ACID.= C_{16}H_{28}O_{2}. This may be obtained by saponifying linseed oil. It is a liquid acid, and rapidly oxidizes when exposed to the air, becoming converted into oxylinoleic acid, which is incapable of solidification even at low temperatures.

=LIN′SEED.= _Syn._ FLAX SEED; LINI SEMINA, L. The seed of _Linum usitatissimum_ (Linn.), or common flax. (Ph. L.) Oily, emollient, demulcent, and nutritive. Ground to powder (linseed meal; farina lini), it is used for poultices. The cake left after expressing the oil (linseed cake) contains, when of average quality, in 100 parts, moisture, 12·70; oil, 11·32; albumenoids, 28·21; mucilage, &c., 29·42; indigestible fibre, 12·46; ash, 5·89. It is used for feeding cattle. Under the form of tea or infusion it is used as a diluent, and to allay irritation in bronchial, urinary, and other like affections. See INFUSION OF LINSEED.

=LINSEED CAKE.= See LINSEED.

=LINT.= _Syn._ LINTEUM, L. White linen-cloth, scraped by hand or machinery, so as to render it soft and woolly. The hand-made lint is now little used; it was prepared from pieces of old linen-cloth. The machine-made lint is prepared from a fabric woven on purpose. A lint made from cotton (cotton-lint) is now largely manufactured; it is much inferior to the true lint, being a bad conductor of heat. Lint is used for dressing ulcers, either alone or smeared with some suitable ointment or cerate.

=Lint, Medica′ted.= _Syn._ LINTEUM MEDICATUM, L. NIGRUM, L. INFERNALE, L. _Prep._ 1. Nitrate of silver, 20 to 30 gr.; distilled water, 1 fl. oz.; dissolve, saturate dry lint, 1/2 oz., with the solution, and expose it in a saucer or capsule to the light and air, until it has become black and dry.

2. Nitrate of silver and nitrate of copper, of each 1/2 dr.; lint, 1 oz.; water, 1-1/2 fl. oz.; as the last. Used to dress old and indolent ulcers.

=LIP SALVE.= See SALVE.

=LIQUA′TION.= The process of sweating out by heat the more fusible metals of an alloy. Metallurgists avail themselves of this method in assaying and refining the precious metals and procuring antimony and some other metals from their ores.

=LIQUEFA′′CIENTS.= _Syn._ RESOLVENTS; LIQUEFACIENTIA, RESOLVENTIA, L. In _pharmacy_, substances or agents which promote secretion and exhalation, soften and loosen textures, and promote the absorption or removal of enlargements, indurations, &c. To this class belong the alkalies, antimony, bromine, chlorine, iodine, mercury, sulphur, &c., and their preparations.

=LIQUEFAC′TION.= The assumption of the liquid form. It is usually applied to the conversion of a solid into the liquid state, which may arise from increase of temperature (fusion), absorption of water from the atmosphere (deliquescence), or the action of a body already fluid (solution).

=Liquefaction of Gases.= Under the combined influence of pressure and cold, all the gases may be liquefied, and some even solidified. The first satisfactory experiments in this direction were made by Faraday, who succeeded in reducing to the liquid condition eight bodies which had hitherto been regarded as permanent gases, namely, ammonia, carbonic anhydride, chlorine, cyanogen, hydrochloric acid, nitrous oxide, sulphuretted hydrogen, and sulphurous anhydride. His method of proceeding was very simple:——the materials were sealed up in a strong, narrow, glass tube, bent so as to form an obtuse angle, together with a little ‘pressure gauge,’ consisting of a slender tube closed at one end, and having within it, near the open extremity, a globule of mercury. The gas, being disengaged by the application of heat or otherwise, accumulated in the tube, and by its own pressure brought about liquefaction. The force required for this purpose was judged of by the diminution of volume of the air in the pressure gauge. By employing powerful condensing syringes, and an extremely low temperature, Faraday subsequently succeeded in liquefying olefiant gas, hydriodic and hydrobromic acids, phosphuretted hydrogen, and the gaseous fluorides of silicon and boron. He failed, however, with oxygen, hydrogen, nitrogen, nitric oxide, carbonic oxide, and coal-gas, all of which refused to liquefy at the temperature of -166° Fahr., while subjected to pressures varying in different cases from 27 to 58 atmospheres.

Within the last year, however, viz. toward the end of 1877, these hitherto refractory gases have been reduced to the liquid, and, in the case of hydrogen, to the solid state. These results have been accomplished by subjecting the gases to a pressure considerably greater than that employed by Faraday, combined with the expedient of the sudden removal of this pressure, whereby the escaping gas (previously enormously reduced in temperature) in the act of expansion robs the remainder of so much of its heat as to leave it in the fluid condition.

The liquefaction of oxygen was accomplished independently by M. Cailletet, of Paris, and M. Pictet, of Geneva; the French chemist having effected it on December 2nd, 1877, and the Swiss one on the 22nd of the same month.

Simultaneously with Cailletet’s announcement of the liquefaction of oxygen, that of carbonic oxide was made by the same chemist; who, about three weeks after at a meeting in the Paris Academy of Sciences, stated that he had also reduced hydrogen, nitrogen, and atmospheric air to the fluid state.

In the previous November he had been equally successful in converting gaseous nitric oxide into a liquid.

M. Cailletet, in a communication to the Paris Academy of Sciences, read by M. Dumas at a meeting of that body on 24th December, 1877, thus describes the process by which he liquefied the gases oxygen and carbonic oxide.

“If oxygen or pure carbonic oxide be enclosed in a tube such as I have before described, and placed in an apparatus for compression like that which has already been worked before the Academy,[17] and the gas be then lowered in temperature to 29° C., by means of sulphurous acid and at a pressure of about 300 atmospheres, the two gases preserve their gaseous state.

[Footnote 17: This apparatus, which consists of a hollow steel cylinder, to which is attached a strong glass tube, is described in the ‘Comptes Rendus,’ tome 85, p. 851. The gas is forced into it by means of a hydraulic pump with the intervention of a cushion of mercury.]

“But if they are allowed to suddenly expand, this expansion, according to the formula of Poisson, reducing them to a temperature at least 200° C. below their initial temperature, causes them immediately to assume the appearance of an intense fog, which is caused by the liquefaction and perhaps by the solidification of the oxygen or carbonic acid.

“The same phenomenon is also observed, upon the expansion of carbonic acid, and of protoxide and binoxide of nitrogen, when under strong pressure.

“This fog is produced with oxygen, even when the gas is at the ordinary pressure, provided time is allowed for it to part with the heat it acquires in the mere act of compression.

“This I demonstrated by experiments performed on Sunday, the 16th December, at the Chemical Laboratory of the Ecole Normale Supérieure, before a certain number of savants and professors, amongst whom were some members of the Academy of Sciences. I had hoped to find in Paris, together with the materials necessary for the production of a high degree of cold (protoxide of nitrogen or liquid carbonic acid), a pump capable of supplying the place of my compression apparatus at Châtillon-sur-Seine. Unfortunately a pump well fixed and suited to this sort of experiment could not be found in Paris, and I was obliged to send to Châtillon-sur-Seine for the refrigerating substances for collecting the condensed matters on the walls of the tube.

“To know whether oxygen and carbonic oxide are in a liquid or a solid state in the fog would necessitate an optical experiment more easy to imagine than to accomplish, because of the form and the thickness of the tubes containing them. Furthermore, chemical reactions will assure me that the oxygen is not transformed into ozone in the act of compression. I shall reserve the study of all these questions till the apparatus I am now having made is complete.

“Under the same conditions of temperature and pressure, even the most rapid expansion of pure hydrogen gives no trace of nebulous matter. There remains for me only nitrogen to study, the small solubility of which in water induces me to believe that it will prove very refractory to all change of condition.”[18]

[Footnote 18: ‘Comptes Rendus,’ tome 5, p. 1213.]

M. Pictet’s process for liquefying oxygen, although differing in the method of working, is similar in principle to that of M. Cailletet. His paper, which was read at the same sitting of the Academy as M. Cailletet’s, thus describes it:——

“A and B, in the accompanying figure, are two double section and force pumps, coupled together on the compound system, one causing a vacuum in the other in such a manner as to obtain the greatest possible difference between the pressures of suction and forcing.”

The pumps act on anhydrous sulphurous acid contained in the cylindrical receiver c. The pressure in this receiver is such that the sulphurous acid is evaporated from it at a temperature of 65° C. below zero.

The sulphurous acid is forced by the pumps into a condenser, d, cooled by a current of cold water; here it liquefies at the temperature of 25° above zero, and at a pressure of about 2-3/4 atmospheres.

The sulphurous acid returns to the receiver C as it liquefies by the little tube _d_.

E and F are two pumps resembling the preceding, and coupled in the same manner. They act upon carbonic acid contained in a cylindrical receiver H.

The temperature in this latter receiver is such that the carbonic acid evaporates from it at a temperature of 140° C. below zero.

The carbonic acid forced on by the pumps is driven into the condenser K, enclosed in the sulphurous acid receiver C, which has a temperature of 65° below zero; the carbonic acid here becomes liquefied at a pressure of five atmospheres.

The carbonic acid, in proportion as it liquefies, returns to the receptacle H by the small tube _k_.

L is a retort of wrought iron, sufficiently thick to resist a pressure of 500 atmospheres. It contains chlorate of potassium, and is heated in such a manner as to give off pure oxygen. It communicates by a tubulure with an inclined tube, M, made of very thick glass, one metre in length, which is enveloped by the receiver, H, containing carbonic acid at the temperature of 140° below zero.

A tap, N, situated upon the tubulure of the retort, permits of the opening of an orifice, P, which leads into the surrounding air.

After the four pumps have been worked for several hours by means of a steam engine of 15-horse power, and when all the oxygen has been disengaged, the pressure in the glass tube is 320 atmospheres, and the temperature at 140° below zero.

Upon suddenly opening the orifice, P, the oxygen escapes with violence, producing, in doing so, so considerable an expansion and absorption of heat as to cause a liquefied portion to appear in the glass tube, and to spirt out from the orifice when the apparatus is sloped.

It ought to be stated that the quantity of liquefied oxygen contained in the tube one metre long and 0·01 m. in internal diameter, occupied about a third of its length, and issued from the orifice P in the form of a liquid jet.

In a communication to M. Dumas, received two days after the above sitting, M. Pictet described his experiments more fully, prefacing the account by the following very interesting remarks:——“The end to which I have been tending for the last 3 years has been to seek to demonstrate experimentally that molecular cohesion is a general property of bodies without exception.

“If the permanent gases cannot be liquefied, it must be concluded that their constituent particles do not attract each other, and are therefore independent of this law.

“To succeed experimentally in bringing the molecules of a gas into the closest possible proximity, and thus to obtain its liquefaction, certain indispensable conditions are necessary, which I thus sum up:

“1. To have a gas that must be perfectly pure and without a trace of foreign gas.

“2. To have at one’s disposal very powerful means of compression.

“3. To obtain an intense degree of cold, and the abstraction of heat at these low temperatures.

“4. To have a large surface of condensation maintained at these low temperatures.

“5. To have the power of utilising the expansion of the gas under considerable pressure to the atmospheric pressure, which expansion added to the preceding means compels liquefaction.

“With these five conditions fulfilled, we may formulate the following problem.

“When a gas is compressed at 500 or 600 atmospheres, and kept at a temperature of -100° or 140°, and then let expand to the pressure of the atmosphere, one of two things must occur. Either the gas, obeying the action of cohesion, liquefies and yields its heat of condensation to the portion of the gas, which expands and is lost in the gaseous form; or under the hypothesis that cohesion is not a natural law, the gas passes beyond absolute zero, that is to say, it becomes inert, a dust without consistence. The work of expansion would be impossible, and the loss of heat absolute.”

Spite of M. Cailletet’s supposition that nitrogen would prove a very incoercible gas, his experiments showed the contrary, since he found that it easily condensed under a pressure of about 200 atmospheres and at a temperature of 13° C., the conditions as to its sudden expansion being observed.

Hydrogen, the lightest of all the gases, which M. Cailletet could only procure in the form of mist, was unmistakably liquefied by M. Pictet within less than a fortnight afterwards, under a pressure of 650 atmospheres and 140° of cold.

The tap which confined the gas at this pressure, being opened, a jet of a steel blue colour escaped from the orifice, accompanied by a hissing sound, like that given off when a red-hot iron is dipped into cold water. The jet suddenly became intermittent, and a shower of solid particles of the hydrogen fell to the ground with a crackling noise. The hydrogen was obtained by the decomposition of formiate of potash by caustic potash, the gas thus yielded being absolutely pure.

Cailletet states that he succeeded perfectly in liquefying atmospheric air, previously deprived of moisture and carbonic acid, but he omits to mention the pressure and reduction of temperature to which the air was subjected. He liquefied nitric oxide at the pressure of 104 atmospheres and at a temperature of -11° C.

Carbonic anhydride is liquefied on the large scale by condensing it in strong vessels of gun-metal or boiler-plate. Thilorier was the first to procure it in a solid condition. It requires a pressure of between 27 and 28 atmospheres at 32° F. (Adams.) The liquefied acid is colourless and limpid, lighter than water, and four times more expansible than air; it mixes in all proportions with ether, alcohol, naphtha, oil of turpentine, and sulphide of carbon; and is insoluble in water and fat oils. When a jet of liquid carbonic anhydride is allowed to issue into the air from a narrow aperture, such an intense degree of cold is produced by the evaporation of a part, that the remainder freezes to a solid (solid carbonic anhydride), and falls in a shower of snow. This substance, which may be collected, affords a means of producing extreme cold. Mixed with a little ether, and poured upon a mass of mercury, the latter is almost instantly frozen. The temperature of this mixture in the air was found to be -106° Fahr.; when the same mixture was placed beneath the receiver of an air-pump, and exhaustion rapidly performed, the temperature sank to -166°. This degree of cold was employed in Faraday’s last experiments on the liquefaction of gases.

=LIQUEUR.= [Fr.] _Syn._ CORDIAL. A stimulating beverage, formed of weak spirit, aromatised and sweetened. The manufacture of liqueurs constitutes the trade of the ‘compounder,’ ‘rectifier,’ or ‘liquoriste.’

The materials employed in the preparation of liqueurs or cordials are rain or distilled water, white sugar, clean flavourless spirit, and flavouring ingredients. To these may be added the substances employed as ‘finings,’ when artificial clarification is had recourse to.

The utensils and apparatus required in the business are those ordinarily found in the wine and spirit cellar; together with a copper still, furnished with a pewter head and a pewter worm or condenser, when the method ‘by distillation’ is pursued. A barrel, hogshead, or rum puncheon, sawn in two, or simply ‘unheaded,’ as the case may demand, forms an excellent vessel for the solution of the sugar; and 2 or 3 fluted funnels, with some good white flannel, will occasionally be found useful for filtering the aromatic essences used for flavouring. Great care is taken to ensure the whole of the utensils, &c., being perfectly clean and ‘sweet,’ and well ‘seasoned,’ in order that they may neither stain nor flavour the substances placed in contact with them.

In the preparation or compounding of liqueurs, one of the first objects which engages the operator’s attention is the production of an alcoholic solution of the aromatic principles which are to give them their peculiar aroma and flavour. This is done either by simple solution or maceration, as in the manufacture of tinctures and medicated spirits, or by maceration and subsequent distillation. The products, in this country, are called ESSENCES or SPIRITS, and by the French INFUSIONS, and are added to the solution of sugar (SYRUP or CAPILLAIRE) or to the dulcified spirit, in the proportions required. Grain or molasses spirit is the kind usually employed for this purpose in England. As before observed, it should be of the best quality; as, if this is not the case, the raw flavour of the spirit is perceptible in the liquor. Rectified spirit of wine is generally very free from flavour, and when reduced to a proper strength with clear soft water, forms a spirit admirably adapted for the preparation of cordial liquors. Spirit weaker than about 45 o. p., which has been freed from its own essential oil by careful rectification, is known in trade under the title of ‘pure,’ ‘flavourless,’ ‘plain,’ or ‘silent spirit.’ Before macerating the ingredients, if they possess the solid form, they are coarsely pounded, bruised, sliced, or ground, as the peculiar character of the substance may indicate. This is not done until shortly before submitting them to the action of the menstruum; as, after they are bruised they rapidly lose their aromatic properties by exposure to the air. When it is intended to keep them for any time in the divided state they should be preserved in well-corked bottles or jars. The practice of drying the ingredients before pounding them, frequently adopted by ignorant and lazy workmen for the sake of lessening the labour, is, of course, even more destructive to their most valuable qualities than mere exposure to the air. The length of time the ingredients should be digested in the spirit should never be less than 5 or 6 days, but a longer period is preferable when distillation is not employed. In either case the time may be advantageously extended to 10 days or a fortnight, and frequent agitation should be had recourse to during the whole period. When essential oils are employed to convey the flavour, they are first dissolved in a little of the strongest rectified spirit of wine, in the manner explained under ESSENCE; and when added to the spirit, they are mixed up with the whole mass as rapidly and as perfectly as possible. In managing the still, the fire is proportioned to the ponderosity of the oil or flavouring substance, and the receiver is changed before the faints come over; as these are unfitted to be mixed with the cordial. In many cases the addition of a few pounds of common salt to the liquor in the still facilitates the process and improves the product. Ingredients which are not volatile are, of course, always added after distillation. The stronger spirit is reduced to the desired strength by means of either clear soft water or the clarified syrup used for sweetening. The sugar employed should be of the finest quality, and is preferably made into capillaire or syrup before adding it to the aromatised spirit; and not until this last has been rendered perfectly ‘fine’ or transparent, by infiltration or clarification, as the case may demand. Some spirits or infusions, as those of aniseed, caraway, &c., more particularly require this treatment, which is best performed by running them through a clean wine bag, made of rather fine cloth, having previously mixed them with a spoonful or two of magnesia; but in all cases clarification by simple repose should be preferred. Under proper management, liqueurs or cordials prepared of good materials will be found perfectly ‘clear’ or ‘bright’ as soon as made, or will become so after being allowed a few days for defecation; but in the hands of the inexperienced operator, and when the spirit employed is insufficient in strength or quantity, it often happens that they turn out ‘foul’ or ‘milky.’ When this is the case, the liquid may be ‘fined down’ with the whites of 12 to 20 eggs per hogshead; or a little alum, either alone or followed by a little carbonate of sodium or potassium, both dissolved in water, may be added, in the manner described under FININGS.

An excellent and easy way of manufacturing cordial liquors, especially when it is inconvenient to keep a large stock on hand, is by simply ‘aromatising’ and ‘colouring,’ as circumstances or business may demand, spirit 60 or 64 u. p., kept ready sweetened for the purpose. To do this to the best advantage, two descriptions of sweetened spirit should be provided, containing respectively 1 lb. and 3 lbs. of sugar to the gallon. From these, spirit of any intermediate sweetness may be made, which may be flavoured with any essential oil dissolved in alcohol, or any aromatised spirit or ‘infusion’ (see _below_), prepared either by digestion or distillation. As a general rule, the concentrated essences, made by dissolving 1 oz. of the essential oil in 1 pint of the strongest rectified spirit of wine, will be found admirably adapted for this purpose. These essences, which should be kept in well-corked bottles, are employed by dropping them cautiously into the sweetened spirit until the desired flavour is produced. During this operation the liquor should be frequently and violently shaken to produce complete admixture. If by any accident the essence is added in too large a quantity, the resulting ‘milkiness’ or excess of flavour may be removed by the addition of a little more spirit, or by clarification. In this way the majority of the liqueurs in common use may be produced extemporaneously, of nearly equal quality to those prepared by distillation. For those which are coloured, simple digestion of the ingredients is almost universally adopted. The “process by distillation” should, however, be always employed to impart the flavour and aroma of volatile aromatics to the spirit, when expense, labour, and time are of less importance than the production of a superior article.

The French liqueuristes are famed for the preparation of cordials of superior quality, cream-like smoothness, and delicate flavour. Their success chiefly arises from the employment of very pure spirit and sugar (the former in a larger proportion than that adopted by the English compounder), and in the judicious application of the flavouring ingredients. They distinguish their cordials as ‘eaux’ and ‘extraits’ (waters, extracts), or liqueurs which, though sweetened, are entirely devoid of viscidity; and ‘baumes,’ ‘crêmes,’ and ‘huiles’ (balms, creams, oils), which contain sufficient sugar to impart to them a syrupy consistence. The greatest possible attention is given to the preparation of the aromatised or flavouring essences, in France called ‘infusions.’ These are generally made by macerating the aromatic ingredients in spirit at about 2 to 4 u. p. (sp. gr. ·922 to ·925), placed in well-corked glass carboys, or stoneware jars or bottles. The maceration is continued, with occasional agitation, for 3, 4, or even 5 weeks, when the aromatised spirit is either distilled or filtered; generally the former. The outer peel of cedrats, lemons, oranges, limettes, bergamottes, &c., is alone used by our Continental neighbours, and is obtained either by carefully peeling the fruit with a knife, or by ‘oleo-saccharum,’ by rubbing it off with a lump of hard white sugar. Aromatic seeds and woods are bruised by pounding before being submitted to infusion. The substances employed in France to colour liqueurs are, for——blue, soluble Prussian blue, sulphate of indigo (nearly neutralised with chalk), and the juice of blue flowers and berries;——amber, fawn, and brandy colour, burnt sugar or spirit colouring;——green, spinach or parsley leaves (digested in spirit), and mixtures of blue and yellow;——red, powdered cochineal or brazil wood, either alone or mixed with a little alum;——violet, blue violet petals, litmus, or extract of logwood;——purple, the same as violet, only deeper;——yellow, an aqueous infusion of safflower or French berries, and the tinctures of saffron and turmeric.

A frequent cause of failure in the manufacture of liqueurs and cordials is the addition of too much flavouring matter. Persons unaccustomed to the use of strong aromatic essences and essential oils seldom sufficiently estimate their power, and, consequently, are very apt to add too much of them, by which the liqueur is rendered not only disagreeably high flavoured, but, from the excess of oil present, also ‘milky,’ or ‘foul,’ either at once, or, what is nearly as bad, on the addition of water. This source of annoyance, arising entirely from bad manipulation, frequently discourages the tyro, and cuts short his career as a manufacturer. From the viscidity of cordials they are less readily ‘fined down’ than unsweetened liquor, and often give much trouble to clumsy and inexperienced operators. The most certain way to prevent disappointment in this respect is to use too little rather than too much flavouring; for if the quantity proves insufficient, it is readily ‘brought up’ at any time, but the contrary is not effected without some trouble and delay.

A careful attention to the previous remarks will render this branch of the rectifier’s art far more perfect and easy of performance than it is at present, and will, in most cases, produce at once a satisfactory article, ‘fine, sweet, and pleasant.’

The cordials of respectable British ‘compounders’ contain fully 3 lbs. of white lump sugar per gallon, and are of the strength of 60 to 64 u. p. The baumes, crêmes, and huiles imported from the Continent are richer both in spirit and sugar than ours, and to this may be referred much of their superiority. Mere sweetened or cordialised spirits (eaux, of the Fr.) contain only from 1 to 1-1/2 lb. of sugar per gallon.

The purity of liqueurs is determined in the manner noticed under BRANDY, WINE, &c.

The following list embraces nearly all the cordials and liqueurs, both native and imported, met with in trade in this country:——

=Absinthe.= _Syn._ EXTRAIT D’ABSINTHE DE SUISSE; SWISS EXTRACT OF WORMWOOD. _Prep._ From the tops of _Absinthum majus_, 4 lbs.; tops of _Absinthum minus_, 2 lbs.; angelica root, _Calamus aromaticus_, Chinese aniseed, and leaves of dittany of Crete, of each 15 gr.; brandy or spirit at 12 u. p., 4 galls.; macerate for 10 days, then add water, 1 gall.; distil 4 galls. by a gentle heat, and dissolve in the distilled spirit, of crushed white sugar, 2 lbs. Tonic and stomachic.

=Alker′mes.= This liqueur is highly esteemed in some parts of the South of Europe.

_Prep._ 1. Bay leaves and mace, of each 1 lb.; nutmegs and cinnamon, of each 2 oz.; cloves, 1 oz. (all bruised); cognac brandy, 3-1/2 galls.; macerate for 3 weeks, frequently shaking, then distil over 3 galls., and add of clarified spirit of kermes, 18 lbs.; orange-flower water, 1 pint; mix well, and bottle. This is the original formula for the ‘alkermes de Santa Maria Novella,’ which is much valued.

2. Spice, as last; British brandy, 4 galls. water, 1 gall.; macerate as before, and draw over 4 galls., to which add, of capillaire, 2 galls., and sweet spirit of nitre, 1/4 pint. Cassia is often used for cinnamon. Inferior to the last.

=An′iseed Cordial.= _Prep._ 1. From aniseed, 2 oz. (or essential oil, 1-1/2 dr.), and sugar, 3 lbs. per gall. It should not be weaker than about 45 u. p., as at lower strengths it is impossible to produce a full-flavoured article without its being milky, or liable to become so.

2. (ANISETTE DE BORDEAUX.)——_a._ (Foreign.) Aniseed, 4 oz.; coriander and sweet fennel seeds, of each 1 oz. (bruised); rectified spirit, 1/2 gall.; water, 3 quarts; macerate for 5 or 6 days, then draw over 7 pints, and add of lump sugar, 2-1/2 lbs.

_b._ (English.) Oil of aniseed, 15 drops; oils of cassia and caraway, of each 6 drops; rub them with a little sugar, and then dissolve it in spirit (45 u. p.), 3 quarts, by well shaking them together; filter, if necessary, and dissolve in the clear liquor sugar, 1-1/2 lb. See PEPPERMINT (_below_).

=Balm of Molucca.= _Prep._ From mace, 1 dr.; cloves, 1/2 oz.; clean spirit (22 u. p.), 1 gall.; infuse for a week in a well-corked carboy or jar, frequently shaking, colour with burnt sugar q. s., and to the clear tincture add of lump sugar, 4-1/2 lbs.; dissolved in pure soft water, 1/2 gall. On the Continent this takes the place of the ‘cloves’ of the English retailer.

=Bit′ters.= These have generally from 1 to 1-1/2 lb. of sugar per gallon.[19]

[Footnote 19: See article BITTERS.]

=Car′away Cordial.= _Prep._ Generally from the essential oil, with only 2-1/2 lbs. of sugar per gall. 1 fl. dr. of the oil is commonly reckoned equal to 1/4 lb. of the seed. The addition of a very little oil of cassia, and about half as much of essence of lemon or of orange, improves it. See BRANDY (Caraway).

=Ce′drat Cordial.= _Prep._ From essence (oil) of cedrat, 1/4 oz.; pure spirit (at proof), 1 gall.; dissolve, add of water, 3 pints, agitate well; distil 3 quarts, and add an equal measure of clarified syrup. A delicious liqueur. See CRÊME and EAU (_below_).

=Cin′namon Cordial.= _Prep._ This is seldom made with cinnamon, owing to its high price, but with either the essential oil or bark of cassia, with about 2 lbs. of sugar to the gall. It is preferred coloured, and therefore may be very well prepared by simple digestion. The addition of 5 or 6 drops each of essence of lemon and orange peel, with about a spoonful of essence of cardamoms per gall., improves it. 1 oz. of oil of cassia is considered equal to 8 lbs. of the buds or bark. 1 fl. dr. of the oil is enough for 2-1/2 galls. It is coloured with burnt sugar.

=Cit′ron Cordial.= _Prep._ From the oil or peel, with 3 lbs. of sugar per gall., as above. (See _below_.)

=Citronelle.= _Syn._ EAU DE BARBADES. _Prep._ 1. From fresh orange peel, 2 oz.; fresh lemon peel, 4 oz.; cloves, 1/2 dr.; corianders and cinnamon, of each 1 dr.; proof spirit, 4 pints; digest for 10 days, then add of water, 1 quart, and distil 1/2 gall.; to the distilled essence add of white sugar, 2 lbs., dissolved in water, 1 quart.

2. Essence of orange, 1/2 dr.; essence of lemon, 1 dr.; oil of cloves, and cassia, of each 10 drops; oil of coriander, 20 drops; spirit (58 o. p.), 5 pints; agitate until dissolved, then add of distilled or clear soft water, 3 pints; well mix, and filter it through blotting paper, if necessary; lastly add of sugar (dissolved), q. s.

=Clairet.= _Syn._ ROSSALIS DES SIN GRAINES. _Prep._ From aniseed, fennel seed, coriander seed, caraway seed, dill seed, and seeds of the candy-carrot (_Athamantia cretensis_——Linn.), of each (bruised) 1 oz.; proof spirit 1/2 gall.; digest for a week, strain, and add of loaf sugar, 1 lb., dissolved in water, q. s.

=Cloves.= _Syn._ CLOVE CORDIAL. _Prep._ From bruised cloves, 1 oz., or essential oil, 1 fl. dr., to every 3 galls. of proof spirit. If distilled, some common salt should be added, and it should be drawn over with a pretty quick fire. It requires fully 3 lbs. of sugar per gall., and is generally coloured with poppy flowers or burnt sugar. The addition of 1 dr. of bruised pimento, or 5 drops of the oil for every oz. of cloves, improves this cordial. See BALM OF MOLUCCA (_above_).

=Coriander Cordial.= _Prep._ From corianders, as the last. A few sliced oranges improve it.

=Crême d’Anis.= As ANISEED CORDIAL, only richer.

=Crême des Barbades.= As CITRONELLE, adding some of the juice of the oranges, and an additional lb. of sugar per gall.

=Crême de Cacao.= _Prep._ Infuse roasted caracca-cacao nuts (cut small), 1 lb., and vanilla, 1/2 oz., in brandy, 1 gall., for 8 days; strain, and add of thick syrup, 3 quarts.

=Crême de Cedrat.= _Syn._ HUILE DE CEDRAT. _Prep._ From spirit of citron, 1 pint; spirit of cedrat, 1 quart; proof spirit, 3 quarts; white sugar, 16 lbs., dissolved in pure soft water, 2 galls.

=Crême de Macarons.= _Prep._ 1. From cloves, cinnamon, and mace, of each (bruised) 1 dr.; bitter almonds (blanched and beaten to a paste), 7 oz.; spirit (17 u. p.), 1 gall.; digest a week, filter, and add of white sugar, 6 lbs., dissolve in pure water, 2 quarts.

2. Clean spirit (at 24 u. p., sp. gr. ·945), 2 galls.; bitter almonds, 3/4 lb.; cloves, cinnamon, and mace, of each in coarse powder, 1-1/2 dr.; infuse for 10 days, filter, and add of white sugar, 8 lbs.; dissolved in pure water, 1 gall.; lastly, give the liqueur a violet tint with infusion or tincture of litmus and cochineal. An agreeable, nutty-flavoured cordial, but, from containing so much bitter almonds, should be only drank in small quantities at a time. The English use only one half the above quantity of almonds.

=Crême de Naphe.= _Prep._ From sweetened spirit (60 u. p.) containing 3-1/2 lbs. of sugar per gall., 7 quarts; orange-flower water (foreign), 1 quart. Delicious.

=Crême de Noyeau.= See NOYEAU.

=Crême d’Orange.= _Prep._ From oranges, (sliced), 3 dozen; rectified spirit, 2 galls.; digest for 14 days; add, of lump sugar, 28 lbs. (previously dissolved in water, 4-1/2 galls.); tincture of saffron, 1-1/2 fl. oz.; and orange-flower water, 2 quarts.

=Crême de Portugal.= Flavoured with lemon, to which a little oil of bitter almonds is added.

=Curaçao.= _Prep._ From sweetened spirit (at 56 u. p.), containing 3-1/2 lbs. of sugar per gall., flavoured with a tincture made by digesting the ‘oleo-saccharum’ prepared from Seville oranges, 9 in number; cinnamon, 1 dr.; and mace, 3/4 dr., in rectified spirit, 1 pint. It is coloured by digesting in it for a week or 10 days Brazil-wood (in powder), 1 oz., and afterwards mellowing the colour with burnt sugar, q. s.

=Delight of the Mandarins.= From spirit (22 u. p.), 1 gall.; pure soft water, 1/2 gall.; white sugar (crushed small), 4-1/2 lbs.; Chinese aniseed and ambrette or musk seed, of each (bruised) 1/2 oz.; safflower, 1/4 oz.; digested together in a carboy or stone bottle capable of holding double, and agitated well every day for a fortnight.

=Eau de Cedrat.= _Syn._ CEDRAT WATER. As CRÊME DE CEDRAT, but using less sugar.

=Eau de Chasseurs.= See PEPPERMINT (_below_).

=Eau de Vie d’Andaye.= _Syn._ EAU DE VIE D’ANIS; ANISEED LIQUEUR BRANDY. _Prep._ From brandy or proof spirit, 1 gall.; sugar, 3/4 lb.; dissolved in aniseed water, 1 pint.

=Gold Cordial.= _Prep._ From angelica root (sliced), 1 lb.; raisins, 1/2 lb.; coriander seeds, 2 oz.; caraway seeds and cassia, of each 1-1/2 oz.; cloves, 1/2 oz.; figs and sliced liquorice root, of each 4 oz.; proof spirit, 3 galls.; water, 1 gall.; digest 2 days, and distil 3 gallons by a gentle heat; to this add, of sugar, 9 lbs., dissolved in rose water and clean soft water, of each 1 quart; lastly, colour the liquid by steeping in it of bay saffron, 1-1/4 oz. This cordial was once held in much esteem. It derives its name from a small quantity of gold leaf being formerly added to it.

=Huile d’Anis.= See CRÊME D’ANIS (_above_).

=Huile de Vanille.= Flavoured with essence or tincture of vanilla. It is kept in a decanter, and used to flavour liqueurs, grog, &c.

=Huile de Venus.= _Prep._ From the flowers of the wild carrot, 2-1/2 oz., and sugar, 3 lbs. to the gall. It is generally coloured by infusing a little powdered cochineal in it.

=Jargonelle.= _Syn._ JARGONELLE CORDIAL. Flavoured with essence of jargonelle pear (acetate of amyl). Pine-apple cordial and liqueurs from some other fruits are also prepared from the new fruit essences. See ESSENCE.

=Lem′on Cordial.= _Prep._ Digest fresh and dried lemon peel, of each 2 oz., and fresh orange peel, 1 oz., in proof spirit, 1 gall., for a week; strain with expression, add of clear soft water q. s. to reduce it to the desired strength, and lump sugar, 3 lbs. to the gallon. The addition of a little orange-flower or rose water improves it.

=Liquodilla.= Flavoured with oranges and lemons, of each, sliced, 3 in number; with sugar 2-1/2 lbs. per gall.

=Lov′age Cordial.= _Prep._ From the fresh roots of lovage, 1 oz. to the gallon. A fourth of this quantity of the fresh roots of celery and sweet fennel are also commonly added. In some parts a little fresh valerian root and oil of savine are added before distillation. It is much valued by the lower classes in some of the provinces for its stomachic and emmenagogue qualities.

=Oil of Ce′drat.= See CRÊME DE CEDRAT (_above_).

=Orange Cordial.= Like LEMON CORDIAL or CRÊME D’ORANGE, from fresh orange peel, 1/2 lb., to the gallon.

=Parfait Amour.= _Syn._ PERFECT LOVE. _Prep._ Flavoured with the yellow rind of 4 lemons, and a teaspoonful of essence of vanilla to the gallon, with sugar, 3 lbs., and powdered cochineal q. s. to colour.

=Pep′permint.= _Syn._ PEPPERMINT CORDIAL, SPORTSMAN’S C., X. MINT; EAU DE CHASSEURS, Fr. This well-known compound is in greater demand in every part of the kingdom than all the other cordials put together.

_Prep._ 1. From peppermint water and gin or plain spirit (22 u. p.), of each 1 pint; lump sugar, 3/4 lb.

2. (Wholesale.) English oil of peppermint, 5 oz., is added to rectified spirits of wine, 3 pints, and the mixture is agitated well together for some time in a corked bottle capable of holding 4 pints or more; it is then emptied into a cask having a capacity of upwards of 100 galls., and perfectly white and flavourless proof spirit, 36 galls., is poured in, and the whole well agitated for ten minutes; a solution of the best double refined lump sugar, 2-3/4 cwt., in about 35 galls. of pure filtered rain water, is then added, and the contents of the cask well ‘rummaged up’ in the usual manner for at least 15 minutes; sufficient clear rain water to make up the whole quantity to exactly 100 gallons, and holding in solution alum, 5 oz., is next added, and the whole is again well agitated for at least a quarter of an hour, after which the cask is bunged down, and allowed to repose for a fortnight before it is ‘broached’ for sale.

_Obs._ The last formula produces a beautiful article provided the ingredients are of good quality. Care on this point is particularly necessary in reference to the essential oil, which should only be purchased of some known respectable dealer. The sugar should be sufficiently pure to dissolve in a wine-glassful of clear soft water without injuring its transparency, and the cask should be a fresh-emptied gin pipe, or one properly prepared for gin, as, if it gives colour, it will spoil the cordial. When these particulars are attended to, the product is a bright transparent liquor as soon as made, and does not require fining. Should there be the slightest opacity, the addition of 2 oz. of salt of tartar, dissolved in a quart of hot water, will have the effect of ‘clearing it down’ in the course of a few days. The product is 100 galls. of cordial at 64 u. p.

=Pimen′to.= _Syn._ PIMENTO CORDIAL, PIMENTO DRAM. Rather strongly flavoured with allspice or pimento. It has obtained a great repute in the West Indies in diarrhœa, cholera, and bowel complaints generally.

=Rasp′berry Cordial.= _Prep._ From raspberry brandy, capillaire, and water, equal parts. A similar article is prepared by flavouring sweetened spirit with the new ‘raspberry essence.’

=Rat′ifia.= The numerous liqueurs bearing this name are noticed in another part of this volume. See RATIFIA.

=Shrub.= See the article SHRUB in another part of this work.

=Sighs of Love.= _Prep._ 1. From proof spirit flavoured with otto of roses and capillaire, equal parts.

2. From sugar, 6 lbs., pure soft water, q. s. to produce a gallon of syrup, to which add, of eau de rose, 1 pint; proof spirit, 7 pints. It is stained of a pale pink by powdered cochineal. A very pleasant cordial. A drop or two (not more) of essence of ambergris or vanilla improves it.

=Tears of the Widow of Malabar.= _Prep._ As BALM OF MOLUCCA, but employing cloves (bruised), 1/2 oz., mace (shredded), 1 dr., and a teaspoonful of essence of vanilla for flavouring. Some add of orange-flower water, 1/4 pint. It is slightly coloured with burnt sugar.

=Tent.= From plain spirit (22 u. p.) and port wine, of each 1 quart; sherry and soft water, of each 1 pint; orange-flower water and lemon juice, of each 1/4 pint; essence of ambergris, 2 drops (not more); sugar, 2 lbs. See WINE.

=Us′quebaugh.= See the article USQUEBAUGH in another part of this work.

=LIQUEUR DE LA MOTTE.= [Fr.] See DROPS (Golden) and TINCTURE.

=LIQUEUR DORÉE.= [Fr.] _Prep._ Take of cinnamon, bitter orange peel, and Peruvian bark, of each 1/2 oz.; hay saffron, 1/4 oz.; brandy and Malaga wine, of each 3 quarts; digest for a week, strain, and add of lump sugar, 2 lbs. Tonic, stomachic, and stimulant; chiefly used as an agreeable alcoholic dram.

=LIQUEUR DE PRESSAVIN.= [Fr.] _Prep._ From oxide of mercury (freshly precipitated) and cream of tartar, of each 1 oz.; hot water, 1 quart; dissolve and filter. For use 2 spoonfuls of this liquor are added to 1 quart of water.——_Dose._ A wine-glassful 3 or 4 times a day, avoiding the use of common salt. This is simply a solution of potassio-tartrate of mercury, and may be taken in the usual cases in which mercury is administered.

=LIQUODIN′NA.= See LIQUEUR.

=LIQUID-AMBAR.= _Syn._ COPAIBÆ BALSAM. A fluid balsamic juice obtained from the _Liquidamber styraciflua_, an American tree. It closely resembles LIQUID STORAX in its properties, and may be applied to the same purposes. See STYRAX.

=LIQ′UOR.= _Syn._ LIQUOR, L.; LIQUEUR, Fr. This term is given in the London Pharmacopœia to those aqueous solutions commonly though improperly called ‘WATERS,’ ammoniæ liquor potassæ, &c. It is now more correctly applied to the ‘WATERS’ of the British Pharmacopœia. See SOLUTION.

The term ‘liquor’ has also, of late years, been applied to certain concentrated preparations, most of which would be more correctly termed ‘FLUID EXTRACTS,’ as they merely differ from good extracts in their consistence, and from ordinary extracts in containing less starchy matter, albumen, and gum. There is also usually a little spirit added to them to prevent decomposition. Liquors of this kind may be prepared of the finest quality by the same processes that are required for the preparation of good soluble extracts; observing to stop the evaporation as soon as the consistence of treacle is acquired, and when cold, to add 1-4th or 1-5th part of their weight (after evaporation) in rectified spirit. The addition of 3 or 4 drops of the oils of cloves and mustard seed, dissolved in the spirit, will secure them from any risk of ‘moulding’ or fermenting; in fact, with this addition many of them will keep well without spirit, provided they are evaporated sufficiently, and kept in a cool place. The liquors, which are merely concentrated infusions or decoctions, and which, in their consistence, do not even approximate to extracts, may be made in the manner directed under those heads.

Much confusion would be prevented if the terms ‘concentrated decoction,’ ‘concentrated infusion,’ &c., were adopted for those vegetable preparations possessing eight times the usual strength; ‘liquors’ for those of a higher strength, but still sufficiently liquid to be treated as such in dispensing, &c.; and ‘fluid extracts’ for those possessing considerable consistence, and approaching the common extracts in their degree of concentration and mode of preparation. See DECOCTION, INFUSION, ESSENCE, EXTRACT, SOLUTION, &c.

⁂ The following formulæ present some illustrations of the preparation of this class of medicines.

=Liquor of Ammonia.= _Syn._ LIQUOR AMMONIÆ. _Prep._ Strong solution of ammonia, 1 pint; distilled water, 2 pints; mix and preserve in a stoppered bottle. Sp. gr. ·959.

=Liquor of Ammonia, Stronger.= _Syn._ LIQUOR AMMONIÆ FORTIOR. _Prep._ Mix chloride of ammonium in coarse powder 3 lbs., and slaked lime 4 lbs., and introduce the mixture into an iron bottle, placed in a metal pot surrounded by sand. Connect the iron tube which screws air-tight into the bottle in the usual manner, by corks, glass tubes, and caoutchouc collars, with a Woulf’s bottle capable of holding a pint; connect this with a second Woulf’s bottle of the same size, the second bottle with a matrass of the capacity of three pints, in which 22 oz. of distilled water are placed, and the matrass by means of a tube bent twice at right angles, with an ordinary bottle containing distilled water 10 oz. Bottles 1 and 2 are empty, and the latter and the matrass which contains the 22 oz. of distilled water are furnished each with a siphon safety-tube charged with a very short column of mercury.

The heat of a fire, which should be very gradually raised, is to be now applied to the metal pot, and continued until bubbles of condensible gas cease to escape from the extremity of the glass tube which dips into the water of the matrass.

The process being terminated, the matrass will contain about 43 fl. oz. of strong solution of ammonia. Bottles 1 and 2 will now include the first, about 16, the second, about 10 fl. oz. of a coloured ammoniacal liquid.

Place this in a flask closed by a cork, which should be perforated by a siphon safety-tube containing a little mercury, and also by a second safety-tube bent twice at right angles, and made to pass to the bottom of the terminal bottle used in the preceding process. Apply heat to the flask until the coloured liquid it contains is reduced to three fourths of its original bulk. The product now contained in the terminal bottle will be nearly of the strength of solution of ammonia, and may be made exactly so by the addition of the proper quantity of distilled water, or of strong solution of ammonia. Density ·191, contains 32·5 per cent. of ammonia.

_Antidotes._——Vinegar and water followed by acidulated demulcent drinks.

=Liquor, Anodyne.= See SPIRIT OF ETHER.

=Liquor, Antinephritic.= _Syn._ LIQUOR ANTINEPHRITICUS, L. _Prep._ (Adams.) Poppy heads, 6 oz.; water, 1-1/2 pint; boil to one third, strain with pressure, and add of nitrate of potassa, 1 oz.——DOSE, 1 to 2 teaspoonfuls night and morning; in gravel and painful affections of the kidneys and bladder.

=Liquor, Antipodag′ric (Beguin’s).= _Syn._ HOFFMANN’S GOUT LIQUID; LIQUOR ANTIPODAGRICUS HOFFMANNII, L. _Prep._ From Boyle’s fuming liquor, 1 part; spirit of wine, 3 parts. Sudorific.——_Dose_, 20 to 30 drops; or externally, in gout, and other painful affections, either alone or combined with camphor. See AMMONIUM, PERSULPHIDE OF.

=Liquor Antipsor′ic.= _Syn._ LIQUOR ANTIPSORICUS, LOTIO A., L. _Prep._ (Van Mons.) Sulphuret of sodium, 1-1/2 dr.; hydrochlorate of ammonia, 75 gr.; dissolve each separately in water, 1/2 pint, mix the solutions, and filter. In itch and other moist skin diseases.

=Liquor, Bleaching.= See SOLUTION OF CHLORIDE OF LIME.

=Liquor, Blistering.= B. _Syn._ LIQUOR EPISPASTICUS, LINIMENTUM CANTHARIDES. _Prep._ Mix cantharides in powder, 8 oz.; and acetic acid, 4 fl. oz. Pack in a percolator, and after 24 hours pass ether slowly through until 20 fl. oz. are obtained. Keep in a stoppered bottle.

=Liquor, Boyle’s Fu′′ming.= The perhydrosulphate of ammonia.

=Liquor of Calum′ba.= _Syn._ LIQUOR CALUMBÆ, L. Same as CONCENTRATED INFUSION OF CALUMBA.

=Liquor of Cam′phor.= See ESSENCE.

=Liquor of Chiret′ta.= Same as CONCENTRATED INFUSION OF CHIRETTA.

=Liquor of Cincho′na.= _Syn._ LIQUOR OF BARK; CONCENTRATED INFUSION OF BARK, INSPISSATED I. or B.; INSPISSATED I. OF B.; INFUSUM CINCHONÆ SPISSATUM (Ph. L.), L. _Prep._ 1. (Ph. L.) Yellow cinchona bark (bruised), 3 lbs., is macerated in distilled water, 6 pints, at two successive operations, as directed under EXTRACT OF CINCHONA——Ph. L.; the mixed infusions are evaporated by the heat of a water bath to one fourth, and placed aside to settle; the clear portion is decanted, the remainder strained, and the mixed liquid again evaporated until its sp. gr. reaches 1·200; to this, when cold, rectified spirit is dropped in, by degrees, “so that 3 fl. dr. may be added to each fl. oz. of the liquor;” lastly, allow it to repose for 20 days, that the dregs may subside.

_Obs._ It is not at all clear whether the College means 3 fl. dr. of spirit to be added to each fl. oz. of the liquid before its addition, or that it is to be added so that each fl. oz. of the product shall contain that quantity. We presume the former. 1 fl. dr. of this preparation is said to represent fully 4 fl. oz. of the INFUSION OF CINCHONA——Ph. L.; but it is obvious that it must be liable to great variations in strength. “In a general way 1 fl. dr. may be considered equal to 3 fl. oz. of the infusion.” (Pereira.) As commonly met with, this preparation is nearly destitute of the cinchona alkaloids.

2. Yellow cinchona bark, bruised, 56 lbs., and water holding in solution sulphuric acid, 1-1/2 lb., are macerated together, with occasional agitation, in a covered earthen vessel, for 48 hours, after which the liquor is expressed, and the residuum or marc is treated with fresh water; the mixed strained liquid is then evaporated as rapidly as possible in earthenware, to exactly 6 lbs.; to this rectified spirit, 1-1/4 lb., is added, and the whole is set aside for a week or 10 days; the clear portion is, lastly, decanted and preserved in well-closed bottles. The product is very rich in quinine. It is 96 times as strong as the DECOCTION OF CINCHONA——Ph. L., and 12 times as strong as the above preparation of the Ph. L. This preparation resembles the ‘LIQUOR CINCHONÆ’ sold by certain houses in the trade at 24s. per lb., wholesale.

3. Exhaust the bark as above by maceration in 3 successive waters without acid, filter, evaporate the mixed liquors to 7 lbs., and proceed as before. Inferior to the last, and less rich in the cinchona alkaloids. Very thick; scarcely liquid.

4. From PALE BARK:——(LIQUOR CINCHONÆ PALLIDÆ; INFUSUM CINCHONÆ SPISSATUM——Ph. L.) From pale bark, as the last. See INFUSION OF CINCHONA.

=Liquor, Disinfect′ing.= See SOLUTION (Chlorides of Lime, Soda, and Zinc), and DISINFECTING COMPOUNDS.

=Liquor of Er′got.= _Syn._ ESSENCE OF ERGOT OF RYE, CONCENTRATED INFUSION OF E.; ESSENTIA SECALIS CORNUTI, LIQUOR ERGOTÆ, INFUSUM ERGOTÆ CONCENTRATUM, L. _Prep._ Recent ergot of rye (reduced to coarse powder by pounding, or preferably by grinding it in a pepper-mill), 1-1/2 lb., and boiling distilled water, 4 lbs., are digested together in a closed vessel, with frequent agitation until cold, and then put into a wide-mouthed bottle, along with rectified spirit, 2 lbs.; the whole is then allowed to macerate for a week, after which the liquor is expressed and filtered. _Obs._ 4 fl. dr. of this essence are equal to 1 dr. of ergot in substance. It is 8 times the strength of the INFUSION (as usually prepared according to the formula of Pereira and others), and 2-1/2 times the strength of the TINCTURE OF ERGOT of the London Apothecaries’ Hall. This is the only ESSENCE OF LIQUOR OF ERGOT known in the wholesale trade.

=Liquor of Flints.= See SOLUTION.

=Liquor of Gutta Percha.= B. _Syn._ LIQUOR GUTTA PERCHA. Gutta percha in thin slices, 1 oz.; carbonate of lead in fine powder, 1 oz.; chloroform, 8 fl. oz. Add the gutta percha to 6 fl. oz. of chloroform in a stoppered bottle, and shake them frequently till solution has been effected. Then add the carbonate of lead previously mixed with the remainder of the chloroform, and having several times shaken the whole together set the mixture aside, and let it remain at rest until the soluble matter has subsided. Lastly, decant the clear liquid and keep in a well-stoppered bottle.

=Liquor, Libavius’s.= Bichloride of tin.

=Liquor of Mat′ico.= _Syn._ CONCENTRATED INFUSION OF MATICO; LIQUOR MATICONIS, INFUSUM MATICONIS CONCENTRATUM, L. _Prep._ From matico leaves, 1 lb.; rectified spirit, 1/2 pint; distilled water, 32 fl. oz.; digest 10 days, express, and filter. 1 fl. dr. added to 7 fl. dr. of water is equal to 1 fl. oz. of the common INFUSION.

=Liquor of Myrrh.= _Syn._ SOLUTION OF MYRRH; LIQUOR MYRRHÆ, LOCO LIQUAMINIS MYRRHÆ, L. _Prep._ (Ph. Bor.) Extract of myrrh (Ph. Bor.), 1 oz.; distilled water, 5 fl. oz.; mix thoroughly, decant, and strain. It should be of a brownish-yellow colour, and turbid.——_Dose_, 1/2 to 1 fl. dr.

=Liquor of O′pium.= _Syn._ LIQUOR OPII, L. O. CONCENTRATUS, L. OPIATUS, L. See BLACK DROP.[20]

[Footnote 20: Under DROPS, p. 591.]

1. (Messrs Smith.) Opium, 4 oz., is made into an extract, and ‘denarcotised’ by ether; it is then dissolved in alcohol, filtered, evaporated nearly to dryness, and redissolved in water q. s. to furnish 12 oz. of solution; to this is added, of rectified spirit, 2-3/4 oz., with water q. s. to make the whole up to 16 oz.——_Dose_, 3 to 12 drops.

2. (Acetic; LIQUOR OPII ACETICUS, L.) See LAUDANUM (Houlton’s).

3. (Citric; LIQUOR OPII CITRICUS, L.)——_a._ Powdered opium, 1-1/2 oz.; lemon juice, 1-1/2 pint; evaporate to one half, cool, add of rectified spirit, 5 fl. oz., and the next day decant or filter; same strength as ‘LAUDANUM,’

_b._ (LIQUOR MORPHIÆ CITRATIS——Dr Porter.) Opium, 4 oz.; citric acid, 2 oz.; triturate, and add of boiling water, 15 fl. oz.; digest with agitation for 24 hours, and filter. This last has above three times the strength of ‘LAUDANUM,’ It is sadly misnamed.

4. (Hydrochloric; SOLUTION OF MURIATE OF OPIUM; LIQUOR OPII HYDROCHLORICUS, L.——Dr Nichol.) Powdered opium, 1-1/2 oz.; distilled water, 1 pint; hydrochloric acid, 1-1/2 fl. oz.; digest a fortnight, and strain with expression. Same strength as ‘LAUDANUM,’ According to Dr Nichol, this is preferable to every other preparation of opium.

5. (Sedative; BATTLEY’S SEDATIVE SOLUTION OF OPIUM; LIQUOR OPII SEDATIVUS, L.)——_a._ Hard aqueous extract of opium (bruised), 3 oz., is boiled in water, 1-1/2 pint, until dissolved; to the solution, when cold, rectified spirit, 6 oz. is added, together with water, q. s. to make the whole measure exactly 1 quart; the liquor is, lastly, filtered.

_b._ From hard extract of opium, 22 oz.; boiling water, 13 pints; rectified spirit, 3 pints; as the last.

_c._ From extract of opium——Ph. L., 4-1/4 oz.; water, 1 quart; boil till reduced to 34 fl. oz.; cool, filter, and add of rectified spirit, 5 fl. oz., and water, q. s. to make up exactly 1 quart.

_Obs._ The first two formulæ, which vary only in their quantities, are identical with that employed by Mr Battley. As hard extract of opium is not always at hand, we have introduced a formula in which the ordinary extract is ordered. It gives a precisely similar product to the others, provided the cold aqueous decoction is filtered before adding the spirit. Battley’s LIQUOR OPII SEDATIVUS is an excellent preparation, less exciting than opium or laudanum.——_Dose_, 10 to 30 drops. Dr Christison states that 20 drops of Battley’s solution are equal to 30 drops of the common tincture.

=Liquor, Pancreatic= (Van den Corput). _Syn._ LIQUOR PANCREATINI. Pancreatin and carbonate of potash, of each 10 gr.; balm water, 2-1/2 fl. oz.; syrup of orange peel, 5 dr.——_Dose_, 1/2 fl. oz. to 1 fl. oz.

=Liquor of Pepsin.= (Mr Squire.) _Syn._ LIQUOR PEPSINI. _Prep._ 1 drachm of Boudault’s pepsin in 1 oz. of distilled water. Salt must be added if it is to be preserved.——_Dose._ A teaspoonful.

=Liquor of Rhu′barb.= _Syn._ LIQUOR RHEI, INFUSUM RHEI CONCENTRATUM, L. _Prep._ 1. Rhubarb (well bruised), 6-3/4 oz.; water, q. s.; rectified spirit, 1/2 pint; proceed as for INFUSION OF CALUMBA (conc.); to produce a quart. 8 times the usual strength.

2. See INFUSION OF RHUBARB (Concentrated).

3. See EXTRACT OF RHUBARB (Fluid).

=Liquor of Sarsaparil′la.= _Syn._ FLUID EXTRACT OF SARSAPARILLA; LIQUOR SARZÆ, ESSENTIA SARSAPARILLÆ, L. _Prep._ Either the simple or the compound liquor of sarsaparilla may be made from the corresponding decoction, or, preferably, the infusion prepared with water at 125° Fahr., by carefully evaporating it until sufficiently concentrated, and then straining it through flannel, and adding a little spirit. Jamaica sarsaparilla should be alone employed, as the other varieties, especially the Honduras, not only possess less medicinal virtue, and yield less extract, but are very liable to ferment and get mouldy, unless an undue proportion of spirit is added to them. See EXTRACT OF SARSAPARILLA (Fluid).

=Liquor of Sen′na.= _Syn._ LIQUOR SENNÆ, L. Both the FLUID EXTRACT and the CONCENTRATED INFUSION OF SENNA are called by this name, but more generally the former. The following are additional formulæ:——

1. (Duncan.) Senna, 15 lbs.; boiling water, 5 galls.; proceed by the method of displacement, evaporate the product to 10 lbs., add of molasses, 6 lbs. (previously concentrated over a water bath until it begins to congeal on cooling), dissolve, and further add of rectified spirit, 1-1/4 pint, together with water q. s. to make the whole measure exactly 12 pints. Every fl. oz. represents 1 oz. of senna.

2. (Dr Tweedy.) As the last, but using tincture of ginger (prepared with rectified spirit), 1-1/2 pint, instead of the spirit there ordered.

=Liquor of Soap.= _Syn._ LIQUOR SAPONIS, L. See TINCTURE.

=Liquor, Styp′tic.= _Syn._ LIQUOR STYPTICUS, L. _Prep._ (Ph. Slevico-Holsat. 1831.) Alum and sulphate of copper, of each 1-1/2 oz.; sulphuric acid, 1 oz.; water, 1 lb.; dissolve, and filter.

=Liquor of Tarax′acum.= _Syn._ FLUID EXTRACT OF DANDELION; EXTRACTUM TARAXACI FLUIDUM, LIQUOR TARAXACI, L. _Prep._ 1. Dandelion roots (dried), 28 lbs., are rinsed in clean cold water to remove dirt, and then sliced small, and macerated in enough cold water to cover them for 24 hours; the liquid is next pressed out, and after the fecula has subsided the clear portion is decanted, and heated to 180° or 190° Fahr., to coagulate the albumen; the liquid is then filtered while hot and evaporated by steam, or preferably by a current of warm air, until it is reduced to 22-1/2 lbs.; to this rectified spirit, 6 lbs., is added, and after thorough agitation the vessel is set aside for a week or a fortnight, after which the clear portion is gently poured from the sediment and preserved in well-closed bottles in a cool place. A very fine article. It represents an equal weight of the root.

2. The expressed juice of dandelion is heated to near the boiling point, strained, and evaporated, as the last, to a proper consistence; 1/4th or 1/5th of rectified spirit is then added, and the liquid is otherwise treated as before. Very odorous and pale coloured.

3. Dried root (coarsely powered), 1 lb.; water, 1-1/4 pint; rectified spirit, 1/2 pint; digest a week, express the liquor, pass it through a hair sieve into a bottle, and in 10 days decant the clear portion.

4. (Ph. Bor.) Extract of dandelion, 3 parts; water, 1 part (or q. s.); triturated together.

5. (W. Procter.) Fresh root, 2 lbs., is sliced and reduced to a pulp, and macerated with 1/6th of its bulk of rectified spirit for 24 hours; it is then subjected to strong pressure, the marc is treated with water containing a little spirit, 1 pint, and the liquid is again expressed; the mixed product is evaporated to 12 fl. oz., and when cold, rectified spirit, 4 fl. oz. is added, and the whole filtered.

_Obs._ Liquor of taraxacum has a very large sale. The dose is 1 to 2 fl. dr. See EXTRACT.

=Liquor of Valer′ian.= See EXTRACT OF VALERIAN (Fluid).

=Liquor of Vanil′la.= _Syn._ FLUID EXTRACT OF VANILLA; LIQUOR VANILLÆ, EXTRACTUM V. FLUIDUM, L. _Prep._ 1. Vanilla (sliced), 1 lb.; rectified spirit, 3 pints; prepare a tincture either by displacement or maceration, and reduce it, by distillation at the lowest possible temperature, to 1-1/2 lb.; put this into a strong bottle whilst hot, add of white sugar candy (in powder), 1/2 lb., cork down, and agitate the whole until it is nearly cold. Very fine. Used chiefly for its odour and flavour. It represents half its weight of vanilla.

2. (W. Procter.) Vanilla (cut into thin transverse slices), 1 oz.; sugar, 3 oz.; triturate until reduced to fine powder, put it into a strong pint bottle, along with syrup, 1/2 pint; water, 2 oz.; tie down the cork, and set the bottle for half an hour in boiling water; cool, strain, and treat the residue in a like manner with a mixture of water, 6 fl. oz., and rectified spirit, 1 fl. oz.; lastly, mix the two products. Greatly inferior to the last.

=LIQ′UORICE.= _Syn._ STICK LIQUORICE; LIQUORITIA, GLYCYRRHIZÆ RADIX (B. P.), GLYCYRRHIZÆ RADIX, GLYCYRRHIZA (Ph. L. & D.), G. GLABRA (Ph. E.), L. “The root or underground stem of the _Glycyrrhiza glabra_, fresh and dried, cultivated in Britain.” “The recent and the dried root of _Glycyrrhiza glabra_,” or common liquorice. “The fresh root is to be kept buried in dried sand for use.” (Ph. L.) It has a sweetish taste, and is slightly aperient, expectorant, and diuretic. It is a popular demulcent and pectoral. Its extract and solution are much used as a domestic remedy for cough. As a masticatory it allays thirst and irritation.

Composition of the fresh root of liquorice:

Glycyrrhizin 8·60 Gum 26·60 Matter soluble in alcohol, chiefly resin 0·75 Albumen 0·97 Starch 22·91 Woody fibre 13·36 Moisture 26·81 Ash, 3·07 per cent. —— —————— 100·00 (HASSALL.)

Roussin asserts that the sweetness of liquorice root is not due to glycyrrhizin, as has been hitherto assumed, but to an ammoniacal compound of that substance. Glycyrrhizin, when purified four successive times by dissolving it in alcohol, and precipitating the foreign matter accompanying it by ether, is a yellowish substance, insoluble in cold water, and almost tasteless. Treated with dilute solution of potash or soda, it rapidly develops a sweet taste. In liquorice root, however, it is not contained in combination with either of these two alkalies, but appears to exist as an ammoniacal compound, for solutions of potash and soda liberate ammonia, both from the root and the extract. In its compounds with the alkalies glycyrrhizin plays the part of an acid, as it forms true salts capable of undergoing decomposition with most of the metallic salts, and also with the salts of the organic alkaloids. With ammonia it forms two compounds, a basic salt, which yields a deep yellow solution, and another containing less ammonia, the solution of which has an amber colour. The former is produced by dissolving glycyrrhizin in water with an excess of ammonia. Upon evaporating the resulting deep yellow solution to dryness it leaves a yellowish, scaly, shining, brittle, non-hygroscopic residue, which constitutes the second ammoniacal compound. This is readily soluble in cold water, to which it imparts a pale yellow colour and a very sweet taste. The solution turns deep yellow on the addition of a few drops of solution of ammonia, owing to the formation of the basic compound. The pale yellow solution possesses, in a marked degree, the taste of liquorice root, which, indeed, owes its sweetness to this glycyrrhizate of ammonia, or ammoniacal glycyrrhizin, as the author prefers to call it. One gram of this compound imparts the sweet taste of the root to two litres of water.

The author gives the following process for the preparation of the ammoniacal glycyrrhizin in the pure state: The carefully-selected roots, freed from all portions presenting a dark fracture, are scraped, and then well pounded, so as to reduce them to a kind of stringy tow. This substance is macerated in cold distilled water for some hours, pressed, and treated a second time in the same manner. The two liquors are mixed and allowed to stand for some time to deposit the starch. The supernatant liquor is then boiled and filtered, to separate the coagulated albumen. After cooling, sulphuric acid diluted with its weight of water is added gradually, with brisk stirring, until a precipitate is no longer formed. The precipitate, at first gelatinous and flocculent, after standing some time, forms a compact semi-solid mass at the bottom of the vessel. The supernatant liquor is rejected, and after roughly washing the precipitate several times with pure water it is finally kneaded repeatedly in distilled water until all trace of acidity has disappeared. The mass is then well drained and agitated in a flask with three times its weight of 90° alcohol until dissolved, when a similar quantity of 96° to 98° alcohol is added to the syrupy liquid so produced. A little pectic acid is thus precipitated, which is removed by filtration. Ether is then added to the alcoholic liquor as long as a precipitate is formed. After standing twenty-four or even forty-eight hours a blackish pitchy substance is deposited, which adheres to the glass, and allows of the clear liquor being decanted. To this clear liquor is added, in small quantities at a time, alcohol of 90° charged with gaseous ammonia, which determines the formation of a yellow, rather heavy, flocculent precipitate of glycyrrhizate of ammonia. This precipitate is washed rapidly on a fine cloth with a mixture of equal parts of alcohol and ether, pressed and dried in a current of warm air, or over sulphuric acid.

The author suggests the addition of ammoniacal glycyrrhizin to pill masses, powders, or mixtures, and states that its power of masking the taste of nauseous medicines is equal to 100 times its weight of sugar. Sulphate of quinine, sulphate of magnesia, iodide of potassium, and ipecacuanha, lose much of their taste by such an addition.

A dose of cod-liver oil or syrup of iodide of iron is rendered more palatable by being preceded by a small dose of the solid ammoniacal glycerin.[21] Its extract is the common LIQUORICE, SPANISH LIQUORICE, or SPANISH JUICE, of the shops. See EXTRACT, &c.

[Footnote 21: ‘Journal de Pharmacie et de Chimie,’ xii 6-11.]

=LISBON DIET DRINK.= 1. (Foy.) _Prep._ Guaiacum wood, rasped, 1 oz.; sarsaparilla, bruised, 3 oz.; mezereon, sliced, 1/2 oz.; crude antimony (in a rag), 2 oz.; water, 12 pints. Boil down to 8 pints, and add——red sanders, rasped, white sandal, rasped, of each 3 oz.; rosewood, rasped sassafras bark, sliced, of each 1 oz.; liquorice root, sliced, 1/2 oz. Infuse for four hours, strain, and add syrup according to taste.——_Dose_, 1 to 2 pints a day.

2. (Pearson.) Sarsaparilla, bruised, 4 oz.; dried walnut peel, 4 oz.; guaiacum, rasped, 1-1/2 oz.; crude antimony (in a rag), 1/2 oz.; water, 4 pints. Boil down to 3 pints.

=LIST.= The border or selvage torn off a piece of cloth. It is used by the French polishers and law stationers to form their rubbers, and for numerous other purposes.

=LITH′ARGE.= _Syn._ SEMI-VITRIFIED OXIDE OF LEAD; PLUMBI OXYDUM (Ph. L.), PLUMBI OXYDUM SEMI-VITREUM (Ph. D.), LITHARGYRUM (Ph. E.), L. The litharge of commerce is semi-vitrified protoxide of lead, obtained chiefly by scraping off the drops that form on the surface of melted lead exposed to a current of air (dross of lead; plumbum ustum), and heating it to a full red, to melt out any undecomposed metal. The fused oxide, in cooling, forms a yellow or reddish semi-crystalline mass, which readily separates into scales; these, when ground, constitute the ‘powdered litharge’ of the shops. Litharge is also prepared by exposing red lead to a heat sufficiently high to fuse it, and ‘English litharge’ is obtained as a secondary product, by liquefaction, from argentiferous lead ore, when it is often called ‘silver stone.’

_Pur._ “Entirely, or almost entirely, soluble in dilute nitric acid. This solution is blackened by sulphuretted hydrogen. Potassa throws down a white precipitate, which is redissolved by adding the same in excess. If sulphate of soda be added to 100 gr. of this oxide dissolved in nitric acid, 135 gr. of sulphate of lead is precipitated.” (Ph. L.) “50 gr. dissolve entirely, and without effervescence, in 1-1/2 fl. oz. of pyroligneous acid, and the solution precipitated by 53 gr. of phosphate of soda remains precipitable by more of the test.” (Ph. E.) The solution in both acetic and nitric acid should be colourless. It is of great importance to the pharmaceutist to obtain pure litharge, as the slightest impurity will often colour and spoil his lead plaster (EMP. PLUMBI), and solution of diacetate of lead (LIQ. PLUMBI DIACETATIS).

_Uses._ Litharge is employed in pharmacy, to make plasters and several other preparations of lead; by painters as a ‘drier’ for oils; and for various other purposes in the arts.

_Obs._ The litharge of commerce is distinguished by its colour as LITHARGE OF GOLD (LITHARGYRUM AURI, L. AURIUM, L. CHRYSITIS), which is dark coloured and impure, and LITHARGE OF SILVER (SILVER STONE; LITHARGYRUM ARGENTI, L. ARGENTUM, L. ARGYRITIS), which is purer, and paler coloured. The dark colour of the former is generally said to be owing to the presence of red lead. Foreign litharge generally contains copper and iron; and, not infrequently, a little silver and silica. These are readily detected by the usual tests. In grinding litharge, about 1 lb. of olive oil is usually added to each 1 cwt. to prevent dust. The best solvents of litharge are nitric acid and acetic acid. As it slowly absorbs the carbonic acid of the air, it generally effervesces slightly when treated with acids, and this effervescence is stronger in proportion to its age. See LEAD.

=LITH′IUM.= Li. The metallic base of LITHIA, first obtained by Sir H. Davy by exposing hydrate of lithium in contact with mercury to galvanic action, and decomposing the resulting amalgam by distillation. It is now obtained by fusing pure chloride of lithium in a small, thick, porcelain crucible, and decomposing it while in a fused state by a current of electricity. It is a white metal, like sodium, very oxidisable, fusing at 356°, and having a sp. gr. of ·59. It is the lightest metal known. It belongs to the ‘alkaline group,’ of which potassium, sodium, cæsium, and rubidium, are the other members.

Lithium forms salts analogous to those of sodium, but usually somewhat less soluble. They can be distinguished from those of potassium and sodium by the phosphate and carbonate, being only sparingly soluble in water,——from those of barium, strontium, and calcium, by forming crystallisable and soluble salts with sulphuric acid and oxalic acid,——and from those of magnesium, by the solution of its carbonate exhibiting an alkaline reaction. Heated on platinum, they tinge the flame of the blowpipe carmine red. The salts of lithium may generally be formed by dissolving the hydrate or carbonate in dilute acids.

=Lithium, Benzoate.= LiC_{7}H_{5}O_{2},H_{2}O. (Paris Pharm. Society.) Benzoic acid, 122 grams; lithium carbonate, 37 grams. Suspend the benzoic acid in 10 parts of water, add the lithium carbonate, and heat. Solution takes place with effervescence, and upon evaporation, handsome, much flattened, more or less elongated prismatic crystals are obtained.

Lithium benzoate is very soluble in water. One grain of the salt calcined, and then treated with slight excess of sulphuric acid, and heated to redness should give 0·376 gram of lithium sulphate.

=Lithium, Bromide of.= LiBr. To 37 grams of carbonate of lithium suspended in 200 grams of distilled water, 80 grams of bromine are added. A current of sulphuretted hydrogen is then passed through the mixture until the whole of the bromide has disappeared. Hydro-bromic acid is thus formed, which decomposes the carbonate of lithium, bromide of lithium being produced and sulphur set free. The mixture is then gently heated to drive off the excess of sulphuretted hydrogen and to agglutinate the sulphur. After filtration the liquor is concentrated, and if it be desired to obtain the bromide in crystals, the desiccation is finished under a bell jar by means of sulphuric acid.

=Lithium, Car′bonate of.= Li_{2}CO_{3}. _Syn._ CARBONATE OF LITHIA; LITHIÆ CARBONAS (B. P.). _Prep._ To an aqueous solution of sulphate of lithium add a strong solution of carbonate of ammonium, collect the precipitate, drain, and press, wash with a little rectified spirit, and dry. By dissolving it in boiling water, and slowly evaporating the solution, crystals may be obtained.

_Prop., &c._ It resembles carbonate of magnesium in appearance; is soluble in about 100 parts of cold water, and in considerably less of boiling water, and is insoluble in alcohol. The tests for its purity given in the B. P. are——in giving no precipitate with oxalate of calcium or lime water, and leaving, when 10 grains are neutralised with sulphuric acid and ignited, 14·86 grains of dry sulphate. It has been proposed by M. Lipowitz, Dr Garrod, and others, as a solvent for uric acid calculi. According to Biswanger, 1 part of carbonate of lithia in 120 parts of water takes up, at blood-heat, nearly 4 parts of uric acid. Mr Alexander Ure recommends a dilute solution of this substance as an injection in lithic calculus, as it is a better solvent of uric acid than either borax or the alkaline carbonates. “Of all the various menstrua hitherto recommended, none appear to promise more favorably than the carbonate of lithia.” “If by means of injections” (of this solution) “we can reduce a stone at the rate of a grain or more an hour, we shall not merely diminish the bulk of the calculus, but further loosen its cohesion, disintegrate it, so to speak, causing it to crumble down, and be washed away in the stream of urine.” (Mr A. Ure.)——_Dose_, 2 to 5 gr., twice or thrice a day; as an injection, 1 gr. to water, 1 fl. oz.

=Lithium, Citrate of.= Li_{3}C_{6}H_{5}O_{7}. _Syn._ LITHIÆ CITRAS (B. P.). A white deliquescent amorphous powder, made by acting on 50 grains of lithium carbonate with 100 of citric acid, and is readily soluble in 2-1/2 parts of water.

_Tests, &c._ 20 grains burnt at a low red heat until white leave 10·6 grains of carbonate of lithium. Its medical properties are similar to those of the carbonate.——_Dose_, 5 to 16 grains, largely diluted.

=Lithium, Citrate of, Effervescing.= (Paris Pharm. Society.) Citric acid, 40 grams; sodium bicarbonate, 50 grams; lithium bicarbonate, 10 grams. Mix the powders and place them in a flat-bottomed vessel having a large surface; heat to about 100° C., stirring the powder continually until it takes the granular form, then by means of appropriate sieves obtain granules of suitable and uniform size, and preserve the preparation in well-closed bottles.

=Lithium, Oxide of.= Li_{2}O. _Syn._ LITHIA. An alkaline earth found in petalite, &c., and in small quantities in most mineral waters.

_Prep._ Petalite (a silicate of aluminum and lithium) in powder mixed with twice its weight of fluor spar is heated with strong sulphuric acid as long as acid vapours are given off. The residue is treated with ammonia, boiled, and filtered, evaporated to dryness, and heated to redness. The residue consists of sulphate of lithium, from which the oxide is obtained by decomposing it with acetate of barium, filtering and heating after having evaporated the solution to dryness.

This yields the so-called oxide, which is in reality the hydrate, LiHO, and is a white, non-volatile, soluble, caustic solid. The true oxide is a white powder decomposed by water forming the hydrate, and obtainable by igniting the metal in oxygen.

=Lithia, Effervescing Solution of.= _Syn._ LIQUOR LITHIÆ EFFERVESCENS. _Comp._ Water charged with carbonic acid and holding in solution carbonate of lithium. 10 fl. oz. contain 5 grains of the carbonate.——_Props._ Colourless liquid, possessing powerful diuretic properties.——_Use._ Antilithic, for dissolving calculi of uric acid.——_Dose_, 5 to 10 fl. oz.

=LITHOFRACTEUR.= See BLASTING POWDERS.

=LITHOG′RAPHY.= The art of tracing letters, figures, and other designs, on stone, and transferring them to paper by impression. Our notice of this beautiful and useful art must necessarily be brief.

There are two methods of lithography in general use. In the one, a drawing is made on the stone with a lithographic crayon, or with lithographic ink; in the other method the design is made on lithographic paper, which, on being moistened and passed through the press, leaves its design on the surface of the stone, reversed. In either method, water acidulated with nitrous acid, oil of vitriol, or hydrochloric acid, is poured over the stone, and this, by removing the alkali from the chalk or ink, leaves the design on it in a permanent form, at the same time that it ‘etches’ away a portion of the lights, and renders the surface more absorbent of water.

The process of lithographic printing is as follows:——Water is thrown over the stone, the roller charged with printing ink is passed over the surface, the paper is applied, and a copy is obtained by the action of the lithographic press. The same process must be had recourse to for each copy. The nature of the stone is such that it retains with great tenacity the resinous and oily substances contained in the ink or crayon employed to form the design and also absorbs water freely; this, combined with the peculiar affinity between resinous and oily substances, and their mutual power of repelling water, occasions the ink on the printing roller to adhere to the design, and to leave untouched the lights.

The stones are prepared for lithography by polishing in the ordinary way; the style of work for which they are intended determining the degree of labour bestowed upon them. For crayon drawings the surface should have a fine grain, but the finish of the stone must depend upon the desired softness of the intended drawing; for writing or drawing on in ink the surface must receive a higher polish, and must be finished off with pumice-stone and water.

The best lithographic stones are obtained from Solenhofen, near Munich, and from Pappenheim, on the banks of the Danube. The white lias which lies immediately under the blue, near Bath, also yields good lithographic stones, and furnishes the principal portion of those employed in this country. See CRAYONS, INK and PAPER.

=LITHONTRYP′TICS.= _Syn._ LITHOTRYPTICS, LITHONTRYPTICA, L. Under this head are intended numerous substances (LITHICS; LITHICA, L.) used to prevent the formation of urinary calculi, or to dissolve them when already formed. Those employed with the former intention are more correctly termed ANTILITHICS (ANTILITHICA, L.), and those with the latter, LITHONTRYPTICS, or LYTHONLYTICS (LITHONTRYPTICA, LITHONLYTICA, L.).

The following are the principal substances included under this head by pharmacological writers:——Alkalies and their carbonates, benzoic acid, borax, carbonate of lithia, effervescing solution of lithia, carbonic acid, cinnamic acid, diluents (generally), diuretics (generally), juniper, malic acid, Malvern waters, mineral acids, nitrosaccharate of lead, opium, phosphate of soda, phosphoric acid, poppies, turpentines, uva ursi, vegetable acids, vegetable astringents, vegetable bitters, Vichy waters, wall pellitory, water (pure).

=LIT′MUS.= _Syn._ TURNSOLE; LACMUS, LACCA CÆRULEA, L. MUSIVA, L. MUSCI, L. A blue substance prepared by the united influence of water, air, ammonia, and either potassa or soda, from _Rocella tinctoria_, _Lecanora tartarea_, or any of the other tinctorial lichens capable of yielding archil, by a process essentially similar to that adopted for the latter substance, except that chalk is generally used to form the paste, which is moulded into cakes and dried.

_Pur., &c._ “Soluble in both water and alcohol. Its blue colour is reddened by acids, and is restored by the addition of alkalies.” (Ph. L. 1836.) It is extensively used by the dyer as a red and crimson colouring matter, and by the chemist as a test for acids.

The colouring matter of litmus, when purified as much as possible, may be kept for an indefinite period unaltered in glycerin. Litmus is treated with hot water, and the solution, after concentration, is mixed with a sufficient quantity of alcohol (of 80 per cent.) to precipitate the colouring matter. After standing for twenty hours the alcohol is poured off, and carries with it a dirty blue foreign substance, which frequently occurs in litmus, and is not altered by acids. The sediment is treated with hot water, which dissolves it on account of the potassium carbonate which is present.

To remove this carbonate, sulphuric acid is added till the liquid assumes a faint wine tint; it is then heated to boiling for a few minutes, and again rendered blue by the addition of a few drops of lime water. After the lapse of twenty-four hours the liquid is filtered, and evaporated to a syrup, and left all night in a cool place, when the potassium sulphate crystallises out in the form of a crust. It is then filtered through a moist cotton mixed with glycerin, and carefully preserved from damp.[22] See ARCHIL, CUDBEAR, &c.

[Footnote 22: J. C. Martenson, from ‘Chem. Centr.,’ translated into the ‘Journal of the Chemical Society.’]

=LIVE-LONG.= Digestive candy. See CANDYING.

=LIV′ER.= _Syn._ HEPAR, L. A large abdominal viscus, the exclusive duty of which, until recently, was stated by physiologists to be to secrete bile; but the secretion of sugar for combustion in the lungs or capillaries is now said to be one of its chief duties. The liver is subject to several diseases, both functional and organic, among which inflammation (hepatitis) holds the most prominent place. The acute form of this disease is ushered in with pain in the region of the liver, with sickness, costiveness, and a strong, hard, and frequent pulse, with great pain about the clavicle and shoulders. There is cough, oppressed breathing, and often vomiting of bilious matter. The urine is scanty, and of a saffron-yellow colour, and the skin and eyes are also tinged yellow. The treatment consists chiefly in purging with salines accompanied with mercurials, the use of antimonials, and a blister applied over the region of the liver. Bitter tonics, as calumba, cascarilla, and gentian may afterwards be had recourse to; and if the patient resides in a hot climate a change to a temperate one should be made, if possible. Chronic hepatitis requires similar treatment, but of a less active character. The more usual causes of diseases of the liver, besides those common to the other viscera, are residence in a hot climate, and the excessive use of highly seasoned food and alcoholic liquors.

=Liv′er.= _Syn._ HEPAR, L. In _chemistry_ and _pharmacy_, a term formerly applied to numerous substances, on account of their colour; as liver of antimony (HEPAR ANTIMONII), liver of sulphur (HEPAR SULPHURIS), &c.

=Liver, Edible.= The livers of animals, such as the bullock, the calf, and the sheep, contain a large amount of nitrogenous matter,[23] as may be seen from the following analysis by Payen:

[Footnote 23: Hence the instinct that leads man to cook it with a food rich in carbon——such as fat bacon.]

_Composition of Calf’s Liver._

Nitrogenous matter 20·10 Fat 3·58 Carbo-hydrates (amyloid matter) 0·45 Saline matter 1·54 Water 72·33 —————— 98·03

They are generally regarded as indigestible articles of diet, and as such should be avoided by dyspeptics.

It is of great importance to have the livers of animals thoroughly cooked, so as to ensure the destruction of a dangerous parasite——the _Distoma hepatica_, the liver fluke——that frequently infests them.

The foie gras, of which the celebrated Strasbourg pie is made, is the abnormally enlarged or, rather, diseased liver of the goose, brought to its enormous size and fatty condition by subjecting the bird to close confinement in a hot place and overfeeding it.

=LIVER AND BACON.= The liver must be washed, not soaked, then wiped dry and cut into slices. Flour each slice. Remove the rind from the bacon, and cut it into rashers. Let the bacon be fried first, then stand it in a hot dish before the fire during the time the liver is being fried in the melted fat from the bacon. When the liver is cooked place it on the bacon. Next mix a dessert-spoonful of flour into a smooth paste with a cupful of water, stir in it a pinch of pepper and salt, and pour it into the frying-pan; let it just boil, stirring it meanwhile, and, lastly, strain it over the liver and bacon.

=LIXIVIA′TION.= The process of dissolving out or extracting the saline matter of bodies, more especially of ashes, the residua of distillations, &c., by means of ablution or digestion in water. The solution so obtained is called a ‘LYE,’ ‘LEY,’ or ‘LIXIVIUM,’ and the salts resulting from the evaporation of such solutions ‘LIXIVIAL SALTS,’

=LLA′MA.= _Syn._ GUANACO; LAMA, L. A genus of animals of the family _Bovidæ_ and tribe _Camelina_. The llama is confined to South America, and may be regarded as the representative of the camel in the New World. The most important species are _Lama vicugna_ (the VICUNA) and _L. Guanacus_ (the GUANACO). The wool of llamas is woven into stuffs for _ponchos_, and made into cords, sacks, &c. See ALPACA.

=LOAD′STONE.= _Syn._ LODESTONE, MAGNESIAN STONE, MAGNETIC IRONSTONE. Native magnetic oxide of iron (Fe_{3}O_{4}). It is often found massive, frequently crystallised, and occasionally in beds of considerable thickness. Its colour varies from reddish black to deep grey. Native magnets from Arabia, China, and Bengal are commonly of a reddish colour, and are powerfully attractive. Those found in Germany and England have the colour of unwrought iron; those from Macedonia are more black and dull.

=LOAM.= A native mixture of clay, sand, and oxide of iron, with more or less chalk. Loamy soils are of this description. They are called heavy or light, according to the proportion of clay; and sandy, calcareous, or gravelly, just as sand, gravel, or chalk, form a characteristic portion of them.

=LOBEL′IA.= _Syn._ INDIAN TOBACCO; LOBELIA (B. P., Ph. L. E. & D.), L. “The flowering herb of _Lobelia inflata_” (B. P., Ph. L.), or bladder-podded lobelia. The herb has an unpleasant odour, and an acrid, burning, nauseous taste, somewhat resembling that of tobacco. In small doses (1 to 3 gr.) it is expectorant and diaphoretic; in larger doses (5 to 15 gr.) nauseant and emetic; and in excessive doses, poisonous. According to Dr Pereira, its principal value is that of an anti-spasmodic. It has been highly recommended by Dr Elliotson in spasmodic asthma. He commences with small doses, and gradually increases them unless headache or nausea occurs. Others give a full dose at or before the commencement of the fit. It has been also tried in croup, hooping-cough, and other diseases of the respiratory organs, with variable effect.

Lobelia is the panacea of Dr Coffin, the author of the pretended system of medicine irreverently called ‘Coffinism.’

=LOBEL′IC ACID.= The acid existing in decoction of lobelia. It closely resembles gallic acid. It reddens litmus, and is precipitated by several metallic salts.

=LOBEL′INE.= _Syn._ LOBELINA, L. A light yellowish-brown oily substance, found by Calhoun, of Philadelphia, in _Lobelia inflata_. It is volatile, soluble in alcohol, ether, and water; and in oil of turpentine, oil of almonds, and some other fixed oils; with the acids it forms crystallisable salts, which are soluble. It may be obtained from the seeds by the action of alcohol acidulated with acetic acid, evaporating, treating with magnesia and then with ether, and again evaporating. 1 oz. of the seeds furnishes 2 gr. When perfectly pure, 1 gr. will kill a large dog.

=LOB′STERS.= See SHELL FISH.

=LOCK′SOY.= Rice boiled to a paste and drawn into threads. Used to thicken soups. It is imported from China.

=LODGING-HOUSES.= The following sections of the Public Health Act of 1875 embody the regulations in force with regard to _common_ lodging-houses:

(S. 76.) Every local authority shall keep a register, in which shall be entered the names and residences of the keepers of all common lodging-houses within the district of such authority, and the situation of every such house, and the number of lodgers authorised according to this Act to be received therein.

A copy of any entry in such register certified by the person having charge of the register to be a true copy shall be received in all courts and on all occasions as evidence, and shall be sufficient proof of the matter registered without production of the register, or of any document or thing on which the entry is founded; and a certified copy of any such entry shall be supplied gratis by the person having charge of the register to any person applying at a reasonable time for the same.

(S. 77.) A person shall not keep a common lodging-house or receive a lodger therein until the house has been registered in accordance with the provisions of this Act, nor until his name as the keeper thereof has been entered in the register kept under this Act; provided that when the person so registered dies his widow or any member of his family may keep the house as a common lodging-house for not more than four weeks after his death without being registered as the keeper thereof.

(S. 78.) A house shall not be registered as a common lodging-house until it has been inspected and approved for the purpose by some officer of the local authority; and the local authority may refuse to register as the keeper of a common lodging-house a person who does not produce to the local authority a certificate of character in such form as the local authority direct, signed by three inhabitant house-holders of the parish respectively rated to the relief of the poor of the parish within which the lodging-house is situated, for property of the yearly rateable value of £6 or upwards.

(S. 79.) The keeper of every common lodging-house shall, if required in writing by the local authority so to do, affix and keep undefaced and legible a notice with the words, “Registered common lodging-house,” in some conspicuous place on the outside of such house.

The keeper of any such house who, after requisition in writing from the local authority, refuses or neglects to affix or renew such notice, shall be liable to a penalty not exceeding £5, and to a further penalty of 10s. for every day that such refusal or neglect continues after conviction.

(S. 80.) Every local authority shall from time to time make bye-laws:

1. For fixing from time to time, varying the number of lodgers who may be received into a common lodging-house, and for the separation of the sexes therein; and——

2. For promoting cleanliness and ventilation in such houses; and——

3. For the giving of notices and taking precautions in the case of any infectious disease; and——

4. Generally for the well-ordering of such houses.

(S. 81.) Where it appears to any local authority that a common lodging-house is without a proper supply of water for the use of the lodgers, and that such a supply can be furnished thereto at a reasonable rate, the local authority may by notice in writing require the owner or keeper of such house, within a time specified therein, to obtain such supply, and to do all works necessary for that purpose; and if the notice be not complied with accordingly, the local authority may remove such house from the register until it is complied with.

(S. 82.) The keeper of a common lodging-house shall, to the satisfaction of the local authority, limewash the walls and ceilings thereof in the first week of each of the months of April and October in every year. Penalty for neglect, £2 or less.

(S. 83.) The keeper of a common lodging-house in which beggars or vagrants are received to lodge shall from time to time, if required in writing by the local authority so to do, report to the local authority or to such person as the local authority direct, every person who resorted to such house during the preceding day or night, and for that purpose schedules shall be furnished by the local authority to the person so ordered to report, which schedules he shall fill up with the information required, and transmit to the local authority.

(S. 84.) The keeper of a common lodging-house shall, when a person in such house is ill of fever or any infectious disease, give immediate notice thereof to the medical officer of health of the local authority, and also to the poor-law relieving officer of the union or parish in which the common lodging-house is situated.

(S. 85.) The keeper of a common lodging-house, and every other person having or acting in the care or management thereof, shall, at all times when required by any officer of the local authority, give him free access to such house or any part thereof. Penalty for refusing such access, £5 or less.

(S. 86.) Any keeper of a common lodging-house, or other person having or acting in the care or management thereof, who——

1. Receives any lodger in such house without the same being registered under this Act; or——

2. Fails to make a report after he has been furnished by the local authority with schedules for the purpose, in pursuance of this Act, of the persons resorting to such house; or——

3. Fails to give the notices required by this Act, where any person has been confined to his bed in such house by fever or other infectious disease,——

Shall be liable to a penalty not exceeding £5, and in the case of a continuing offence to a further penalty not exceeding £2 for every day during which the offence continues.

(S. 87.) In any proceedings under the provisions of this Act relating to common lodging-houses, if the inmates of any house or part of a house allege that they are members of the same family, the burden of proving such allegation shall lie on the persons making it.

(S. 88.) Where the keeper of a common lodging-house is convicted of a third offence against the provisions of this Act relating to common lodging-houses, the Court before whom the conviction for such third offence takes place may, if it thinks fit, adjudge that he shall not at any time within five years after the conviction, or within such shorter period after the conviction as the court thinks fit, keep, or have, or act in the care or management of a common lodging-house without the previous licence in writing of the local authority, may withhold or grant on such terms or conditions as they think fit.

(S. 89.) For the purposes of this Act the expression ‘common lodging-house’ includes, in any case in which only part of a house is used as a common lodging-house, the part so used of such house.

_Bye-laws as to Houses let as Lodgings._

(S. 90.) The Local Government Board may, if they think fit, by notice published in the ‘London Gazette,’ declare the following enactment to be in force within the district or any part of the district of any local authority, and from and after the publication of such notice such authority shall be empowered to make bye-laws for the following matter (that is to say):

1. For fixing the number, and from time to time varying the number, of persons who may occupy a house or part of a house which is let in lodgings, or occupied by members of more than one family, and for the separation of the sexes in a house so let or occupied.

2. For the registration of houses so let or occupied.

3. For the inspection of such houses.

4. For enforcing drainage and the provision of privy accommodation for such houses, and for promoting cleanliness and ventilation in such houses.

5. For the cleansing and limewashing at stated times of the premises, and for the paving of the courts and courtyards thereof.

6. For the giving of notices and taking of precautions in case of any infectious disease.

This section shall not apply to common lodging-houses within the provisions of this Act, relating to such houses.

=LOG′WOOD.= _Syn._ CAMPEACHY WOOD; HÆMATOXYLUM (Ph. L. E. & D.), HÆMATOXYLI LIGNUM (B. P.), LIGNUM CAMPECHENSE, L. CAMPECHIANUM, L. The heart-wood of _Hæmatoxylon Campechianum_, a native of the coast of Campeachy, but now common in the West Indies and India. It is a valuable astringent, and its decoction, extract, and infusion are useful remedies in chronic diarrhœa and dysentery, and in hæmorrhages, &c. The extract is an efficient substitute for catechu and kino.

Logwood is extensively employed in dyeing and calico printing, for the production of reds, violets, purples, blacks, drabs, &c. It readily yields its colour both to spirit and boiling water. The colouring matter requires a large quantity of water to dissolve it, but when dissolved can be concentrated to any degree by boiling down. The infusion is of a fine red, turning on the purple or violet; acids turn it on the yellow, and alkalies deepen it. To stuffs mordanted with alum it gives various shades of violet and purple, according to the proportions of the materials. By using solution of tin as the mordant, various shades of red, lilac, and violet, may be obtained. The addition of a little Brazil wood is commonly made to brighten the red. With a mordant of sulphate or acetate of iron it dyes black; and with the addition of a little sulphate of copper greys of various shades. It is, however, chiefly employed, in conjunction with gall-nuts, for blacks, to which it imparts a lustre and velvety appearance. Silk is usually turned through the cold decoction, but for wool the decoction is used either hot or boiling. Logwood is one of the cheapest and most easily managed of the dye stuffs. It is also used to make ink. See HEMATOXYLIN, INK, &c.

=LO′HOCH.= See LINCTUS.

=LOR′ICA.= A species of lute applied as a coating to chemical vessels before exposing them to the fire. Its application is called LORICATION. See LUTE.

=LO′TION.= _Syn._ LOTIO, L. An external application, or wash, consisting of water holding in solution medicinal substances. Lotions may be prepared of any soluble medicaments that are capable of exerting their action by contact with the skin. Writers on pharmacology have arranged them in classes, as sedative, anodyne, stimulant, &c., according to their effects. Sedative and refrigerant lotions are commonly employed to allay inflammation;——anodyne and narcotic lotions, to relieve pain;——stimulant lotions, to induce the maturation of tumours, &c.;——detergent lotions, to clean foul ulcers;——repellent and resolvent lotions, to discuss tumours, remove eruptions, &c.;——counter-irritant lotions, to excite a secondary morbid action, with the intention of relieving one already existing. Lotions are usually applied by wetting a piece of linen with them and keeping it on the part affected; or, in slight cases, by moistening the part with the fingers previously dipped into them. Lotions are more agreeable if made with rose water, but are not thereby rendered more efficacious. In all cases, distilled water, or filtered soft water, is alone admissible as the solvent.

As lotions are, in general, mere extemporaneous or magistral preparations, it will, of course, be only necessary here to give the formulæ for a few of those which are the most useful or the most frequently employed. These will serve as examples from which others may be prepared. As a general rule, the medium dose of any substance dissolved in a fluid ounce of distilled water, forms a lotion of the proper strength, under all ordinary circumstances; or, what is the same thing, the medium dose in grains, taken in scruples, is sufficient for a pint of such a lotion. Thus, the dose of sulphate of zinc is 1 to 3 gr., therefore—— (1 + 3)/2 = 2 gr., which is the proportion of sulphate of zinc to be taken for 1 fl. oz. of water, or 40 gr. for 1 pint. Again, the dose of bichloride of mercury is 1/8 to 3/4 gr.; therefore—— (1/8+3/4)/2 = 7/16 gr.; or nearly 1/2 gr. per fl. oz., and 8-1/2 gr. per pint. In this method extreme or unusual doses, as, for instance, those of sulphate of zinc, as an emetic, in poisoning, &c., are not taken into the calculation. In all cases in which lotions are intended for extremely susceptible parts, it is proper to dilute them with an equal bulk of water. When intended for eye-waters (COLLYRIA), they should be diluted with at least 3 to 4 times their bulk of water. See EMBROCATION, LINIMENT, &c.

=Lotion of Ac′etate of Ammo′′nia.= _Syn._ LOTIO AMMONIÆ ACETATIS, L. _Prep._ 1. Solution of acetate of ammonia, 1 part; water, 2 parts.

2. (Hosp. F.) Solution of acetate of ammonia, rectified spirit, and water, equal parts. Discutient and refrigerant. In ordinary inflammations.

=Lotion of Ac′etate of Lead.= _Syn._ LOTIO PLUMBI ACETATIS, L. _Prep._ 1. (Collier.) Acetate of lead, 1 dr.; distilled water, 8 fl. oz. Sometimes a little vinegar is added. In excoriations, burns, sprains, contusions, &c. See SOLUTION OF DIACETATE OF LEAD.

2. Acetate of lead, 2 gr.; distilled water, 1 oz. (Ophthalmic Hospital.)

=Lotion of Ac′etate of Mercury.= _Syn._ LOTIO HYDRARGYRI ACETATIS, L. _Prep._ Acetate of mercury, 1 scruple; distilled water, 1 pint. Mix.

=Lotion of Ac′etate of Zinc.= _Syn._ LOTIO ZINCI ACETATIS, L. _Prep._ 1. (Béral.) Acetate of zinc, 1-1/2 dr.; water, 1 pint. Astringent; similar to lotion of sulphate of zinc.

2. Acetate of zinc, 1 to 2 gr.; water, 1 oz. An astringent collyrium in ophthalmia, and as injection in gonorrhœa after the acute stage has passed. Neither tincture nor wine of opium gives a precipitate with this lotion.

=Lotion, Acetic.= _Syn._ LOTIO ACETI, L. _Prep._ 1. Vinegar, 1 part; water, 2 or 3 parts. For bruises, contusions, &c., and as a general refrigerant application to sound parts.

2. Vinegar, 1 fl. oz.; cold water, 1/2 pint; as a wash in chronic ophthalmia, &c.

=Lotion, Acid.= See LOTIONS OF ACETIC, =Nitric=, and PHOSPHORIC ACID, &c.

=Lotion of Acon′itine.= _Syn._ LOTIO ACONITINÆ, L. _Prep._ (Turnbull.) Aconitine, 8 gr.; rectified spirit, 2 fl. oz. In neuralgia; applied by means of a small piece of sponge mounted at the end of a stick. It must never be employed when the skin is broken or abraded; and it would be wise, in most cases, to dilute it with double its volume of proof spirit.

=Lotion, Al′kaline.= _Syn._ LOTIO ALKALINA, L. POTASSÆ CARBONATIS, L. _Prep._ (P. Cod.) From salt of tartar, 1 oz.; water, 1 pint. Stimulant and detergent. Diluted with an equal bulk of water, it forms an excellent cosmetic wash to remove scurf from the hair. Sometimes it is made with almond milk instead of water.

=Lotion, Almond, Alkaline.= (Dr A. T. Thomson). _Syn._ Solution of potash, 4 fl. oz.; emulsion of bitter almonds, 5-1/2 fl. oz. To remove the scurf in porrigo furfurans, applied twice a day diluted with warm water.

=Lotion of Al′um.= _Syn._ LOTIO ALUMINIS, L. _Prep._ From alum, 1-1/2 dr.; distilled or rose water, 1 pint. Astringent. For sore gums, nipples, excoriations, &c.

=Lotion, Ammonio-Camphorated.= _Syn._ AQUA SEDATIVA, L. EAU SEDATIVE DE RASPAIL; EAU, OU LOTION AMMONIACALE CAMPHRÉE. No. 1. Liquor ammoniæ (·923), 6 parts; camphorated spirit, 1 part; salt, 6 parts; water, 10 parts. No. 2 contains 8 parts, and No. 3 10 parts of ammonia.

=Lotion, Ammoni′acal.= _Syn._ LOTIO AMMONIÆ, L. AMMONIACALIS, L. _Prep._ 1. Liquor of ammonia, 3 fl. dr.; cold water, 5 fl. oz. As a stimulant to indolent ulcers, and in certain skin diseases.

2. (Swediaur.) Liquor of ammonia, spirit of thyme, and spirit of camphor, equal parts. In headaches; applied to the forehead and temples, and in other cases, as a counter-irritant. In most cases it should be used diluted.

3. (Opiated——Dr Kirkland.) Sal volatile, 3-1/2 fl. oz.; tincture of opium, 1/2 fl. oz.; water, 4 fl. oz. Anodyne, stimulant, and resolvent.

=Lotion, Antiphlogis′tic.= _Syn._ LOTIO ANTIPHLOGISTICA, L. _Prep._ 1. (Copland.) Solution of diacetate of lead, 3 fl. dr.; solution of acetate of ammonia, 2 fl. oz.; distilled water, 1 pint. Refrigerant, sedative, and repellant. Used to allay inflammation, &c.

2. (A. T. Thomson.) Opium, 2 dr., distilled vinegar, 1/2 pint. Anodyne and refrigerant; in swelled joints, &c.

=Lotion of Ar′nica.= _Syn._ LOTIO ARNICÆ, L. _Prep._ 1. Tincture of arnica, 1 fl. dr.; rose water, 2-1/2 fl. oz. In contusions, bruises, extravasations, &c.

2. (Niemann.) Arnica flowers, 1/2 oz.; hot vinegar, 3 fl. oz.; boiling water, 5 fl. oz., infuse until cold, and strain. In acute hydrocephalus; or with water, q. s. to measure a pint, as a common lotion.

=Lotion, Arsenical.= _Syn._ LOTIO ARSENICALIS, L. ACIDI ARSENIOSI, L. _Prep._ 1. Arsenious acid, 5 gr.; water, 1 pint. In psoriasis, &c.

2. (Compound——M. le Febre.) Arsenious acid, 8 gr.; boiling water, 16 fl. oz.; dissolve, and add of extract of hemlock, 1 oz.; solution of diacetate of lead, 3 fl. oz.; tincture of opium, 1 fl. dr. Every morning, in cancer.

=Lotion, Astrin′gent.= _Syn._ LOTIO ASTRINGENS, L. See LOTIONS OF ALUM, SULPHATE OF ZINC, &c.

=Lotion, Barlow’s.= _Prep._ From sulphuret of potassium (in powder), 3 dr.; soap (sliced), 1-1/2 dr.; lime water, 7-1/2 fl. oz.; proof spirit, 2 fl. oz. In itch, ringworm, &c.

=Lotion, Bateman’s.= _Prep_. From bichloride of mercury, 2 gr.; compound spirit of lavender, 1 fl. oz.; dissolve, and add of distilled water, 4 fl. oz. In obstinate cutaneous eruptions, more especially those of a papular character.

=Lotion of Belladon′na.= _Syn._ LOTIO BELLADONNÆ, L. _Prep._ (Graefe.) Extract of belladonna, 1/2 dr.; dilute solution of diacetate of lead, 1/2 pint. Applied to tumours and glandular enlargements.

=Lotion of Benzoin.= LOTIO BENZOINI. Tincture of benzoin, 1; rose water, 40. A nice lotion to protect the face from the heat of the sun.

=Lotion of Bichlo′′ride of Mercury.= _Syn._ LOTIO HYDRARGYRI BICHLORIDI, L. H. CHLORIDI CORROSIVI, L. _Prep._ 1. Corrosive sublimate, 5 to 10 gr.; distilled water, 1 pint. The addition of 5 or 6 gr. of hydrochlorate of ammonia, or as many drops of hydrochloric acid, increases the solvent action of the water, and renders the preparation less liable to change. Some persons dissolve the sublimate in 1 or 2 fl. dr. of rectified spirit before adding it to the water; but this is unnecessary. In obstinate eruptions, glandular swelling, obstinate sores, &c.; also as an injection.

2. (Good.) Corrosive sublimate, 1 dr.; sal ammoniac, 2 dr.; nitre, 4 dr.; water, 6 fl. oz.; dissolve. In itch, &c. For use, it should be diluted with about 3 times its bulk of water.

3. (LOTIO HYDRARGYRI AMYGDALINA——St B. Hosp.) Blanched bitter almonds, 1 oz.; water, 1 pint; make an emulsion, and add of bichloride of mercury (dissolved in a little rectified spirit), 10 gr. This resembles GOWLAND’S LOTION, and may be used for it.

=Lotion of Bismuth.= LOTIO BISMUTHI. Nitrate of bismuth, 6 gr.; corrosive sublimate, 1/2 gr.; spirits of camphor, 1-1/2 minim; water, 1 oz. A soothing lotion in chronic skin affections.

=Lotion, Black.= See LOTION, MERCURIAL.

=Lotion of Borax.= _Syn._ LOTIO BORACIS, L. BORACICA, L. _Prep._ 1. (Dr Abercrombie.) Borax, 2-1/2 dr.; distilled vinegar, 1/4 pint. In ringworm.

2. (Copland.) Borax (in powder), 1 dr.; rose water and orange-flower water, of each 3 fl. oz.; dissolve. A fragrant and effective application to sore gums, sore nipples, excoriations, &c.

3. (Dr Johnson.) Borax, 2 dr.; precipitated chalk, 1 oz.; rose water and rectified spirit, of each 3 oz. For sore nipples.

4. (Dr Meigs.) Borax, 1/2 oz.; sulphate of morphia, 6 gr.; rose water, 8 fl. oz. To allay itching and irritation, especially pruritus vulvæ.

5. Borax, 1; rose water, 24. Cosmetic.

=Lotion, Bro′mine.= _Syn._ LOTIO BROMINII, L. _Prep._ (Dr Glover.) Bromine, 1 dr.; water, 1 pint. As an application to scrofulous ulcers.

=Lotion for Burns.= See LINIMENT.

=Lotion, Camphora′ted.= See LOTION, EVAPORATING.

=Lotion of Cap′sicum.= _Syn._ LOTIO CAPSICI, L. _Prep._ (Griffith.) Tinctures of capsicum and camphor, of each 4 fl. oz.; liquor of ammonia, 2 fl. oz. A powerful rubefacient and counter-irritant.

=Lotion of Carbolic Acid.= (Mr Lister.) _Syn._ LOTIO ACIDI CARBOLICI. _Prep._ 1 part of acid in 20 of water is used to promote the healing of wounds, abscesses, ulcers and burns. A weaker solution of 1 in 40 is in common use in the London hospitals. 5 drops to 1 fl. oz. of glycerin forms a good application to eruptions of the skin.

=Lotion of Car′bonate of So′da.= _Syn._ LOTIO SODÆ CARBONATIS, L. _Prep._ From carbonate of soda, 1/2 oz.; water, 1 pint. To allay itching and irritation. See LOTION, ALKALINE.

=Lotion of Cher′ry Laurel.= _Syn._ LOTIO LAURO-CERASI, L. _Prep._ 1. Cherry-laurel water (distilled), 1-1/2 fl. oz.; distilled water, 1/2 pint. Anodyne; useful to allay irritation, &c. Some persons with delicate skin employ it as a wash after shaving.

2. Cherry-laurel water (distilled), 4 oz.; rectified spirit and ether, of each 1 fl. oz.; extract of belladonna, 2 dr.; agitate well together in the cold. An excellent application in neuralgia, painful tumours, &c.

=Lotion for Chilblains.= See CHILBLAIN, LINIMENT, &c.

=Lotion of Chlo′′rate of Soda.= _Syn._ LOTIO SODÆ CHLORATIS, L. _Prep._ (Darling.) Chlorate of soda, 5 dr.; water, 1/2 pint. In pruritus, &c.

=Lotion of Chlo′′ride of Ammonium.= LOTIO AMMONII CHLORIDI. Chloride of ammonium, 1 oz.; rectified spirit, 1 oz.; water, 10 oz. To this vinegar is sometimes added. Used as a dressing for bruises. See also LOTION OF HYDROCHLORATE OF AMMONIA.

=Lotion of Chlo′′ride of Lead.= _Syn._ LOTIO PLUMBI CHLORIDI, L. _Prep._ (Tuson.) Chloride of lead, 1 dr.; hot distilled water, 1 pint; dissolve. In cancerous ulcerations, painful neuralgic tumours, &c.

=Lotion of Chloride of Tin.= _Syn._ LOTIO STANNI CHLORIDI, L. _Prep._ (Nauche.) Chloride of tin, 1 gr.; distilled water, 2 to 3 fl. oz. In cancerous ulcerations.

=Lotion of Chloride of Zinc.= _Syn._ LOTIO ZINCI CHLORIDI, L. _Prep._ 1. Chloride of zinc, 10 gr. (or solution, 1/2 fl. dr.); water, 1 pint. As a disinfectant and preventive lotion.

2. (Voght.) Chloride of zinc, 8 gr.; extract of aloes, 40 gr.; distilled water, 4 fl. oz. In atonic and foul ulcers.

=Lotion, Chlorina′ted.= _Syn._ LOTIO CHLORINATA, L. _Prep._ 1. (LOTIO CALCIS CHLORINATÆ.)——_a._ From chloride of lime, 3 dr.; water, 1 pint; agitate together for some time, and strain through muslin.

_b._ (Derheims.) Chloride of lime, 1 oz.; water, 1 quart; triturate and filter.

2. (LOTIO SODÆ CHLORINATÆ.) From chloride of soda, as the last. They are both excellent washes for foul ulcers, the itch, &c.; and, when diluted for the teeth, to sweeten the breath, remove the smell of tobacco smoke, to prevent infection, and for various purposes. When intended for application to very tender or abraded surfaces, they must be largely diluted with water.

=Lotion of Chlo′′roform.= _Syn._ LOTIO CHLOROFORMI, L. _Prep._ Chloroform (pure), 1-1/2 fl. oz.; rectified spirit and cold distilled water, of each 1/2 pint. Anodyne. A piece of oiled silk should be laid over the rag to prevent evaporation. The lotion made with water, as commonly prescribed, is inert.

=Lotion for Corns.= See CORN.

=Lotion of Crea′sote.= _Syn._ LOTIO CREASOTI, L. _Prep._ 1. Creasote, 2 fl. dr.; liquor of potassa, 3 fl. dr.; water, 1/2 pint.

2. Creasote, 3 fl. dr.; vinegar and water, of each 1/2 pint. In burns, itch, phagedenic ulcerations, ringworm, chancre, &c.

=Lotion of Cy′anide of Potas′sium.= _Syn._ LOTIO POTASSI CYANIDI, L. _Prep._ 1. (Cazenave.) Cyanide of potassium, 10 gr.; emulsion of bitter almonds, 6 fl. oz. In chronic eruptions and other cases attended with much itching or irritation.

2. (Foy.) Cyanide of potassium, 8 gr.; distilled water, 1 fl. oz. In neuralgia, acute rheumatism, &c.; applied by means of compresses of linen. Both the above are poisonous if swallowed.

=Lotion of Delphin′ine.= _Syn._ LOTIO DELPHINIÆ, EMBROCATIO D., L. _Prep._ (Dr Turnbull.) Delphinine, 20 to 60 gr.; rectified spirit, 2 fl. oz. Used as LOTION OF VERATRIA.

=Lotion of Diac′etate of Lead.= _Syn._ GOULARD’S LOTION; LOTIO PLUMBI DIACETATIS, L. The dilute liquor of diacetate of lead (LIQ. PLUMBI DIACETATIS DILUTUS——Ph. L.). See SOLUTION. Also Solution of subacetate of lead (B. P.), 3 minims, with 7 minims to 1 oz. water.

=Lotion, Evap′orating.= _Syn._ LOTIO EVAPORANS, L. VAPORANS, L. SPIRITUS DILUTI, L. _Prep._ 1. (Copland.) Sulphuric ether, rectified spirit, and solution of acetate of ammonia, of each 1-1/2 fl. oz.; rose water, 3-1/2 fl. oz.

2. (Guy’s Hosp.) Rectified spirit, 1 part; water, 5 parts.

3. (Erasmus Wilson.) Rectified spirit, 1 part; water, 4 to 6 parts.

4. (CAMPHORATED——Ware.) Camphor, 1/2 dr.; elder flowers, 1/2 oz.; rectified spirit, 4 oz.; digest 24 hours, and strain.

_Obs._ The above are soothing and refrigerant, if allowed to evaporate by free exposure; stimulant, if the evaporation is prevented by covering the part with the hand, or a piece of oiled silk. They are useful applications in nervous headaches, restlessness, itching and irritability of the skin, &c. “A little rose water added to the simple water makes an agreeable addition, and sometimes camphor water (julep), or a little Goulard’s extract, may be deemed advantageous, when a greater degree of calming effect is required.” (Eras. Wilson.) Eau de Cologne, diluted with an equal quantity of water, is often used as an evaporating lotion.

=Lotion of Gall-nuts.= _Syn._ LOTIO GALLÆ, L. _Prep._ From gall-nuts (bruised), 1/2 oz.; boiling water, 1 pint; infuse until cold, and strain. Astringent. An excellent application to sore nipples, or to strengthen them before suckling; spirit of wine, 3 fl. oz., may be advantageously added to the cold infusion, and a like portion of water omitted, See DECOCTION.

=Lotion of Glyc′erin.= _Syn._ LOTIO GLYCERINI, L. GLYCERINIÆ, L. _Prep._ 1. Glycerin, 1 oz.; water, 1 pint. To allay itching, and remove dryness, &c., in various skin diseases; also in chaps of the nipples, lips, and hands. For the latter purpose the addition of 2 to 3 dr. of borax is recommended by some writers.

2. Glycerin, 1 oz.; thick mucilage, 2 oz.; lime water, 7 oz. In burns, scalds, chaps, excoriations, &c.

3. (Startin.) Glycerin, 1 oz.; extract of belladonna, 1 dr.; soap liniment, 3 oz.; triturate together. In bruises, sprains, and swelled joints; gouty, neuralgic, and rheumatic pains, &c.

4. (Startin.) Trisnitrate of bismuth, 1/2 dr.; tincture of foxglove and dilute nitric acid, of each 1 fl. dr.; glycerin, 4 dr.; rose water, 8-1/2 fl. oz. To allay the itching in prurigo, and some other skin diseases.

_Obs._ Various lotions may be prepared by dissolving active medicinal substances in glycerin.

=Lotion, Goulard’s.= SEE LOTION OF DIACETATE OF LEAD.

=Lotion, Gout.= _Syn._ LOTIO ANTARTHRITICA, L. _Prep._ 1. Glycerin, 1 oz.; extract of belladonna, 3 dr.; veratrine, 10 gr., dissolved in rectified spirit, 2 fl. oz.; mix, and further add, of water, 17 fl. oz. It is poisonous if swallowed.

2. (‘SCUDAMORE’S G. L.’) From camphor mixture, 9 fl. oz.; rectified spirit, 3 fl. oz. The above are applied on rags or compresses, or are poured on the surface of poultices.

=Lotion, Gowland’s.= This celebrated nostrum is prepared as follows:——Take of Jordan almonds, 1 oz.; bitter almonds, 1/2 oz.; blanch them, and make an emulsion in soft water, 1 pint; to this add of bichloride of mercury, 15 gr.; previously dissolved in rectified spirit, 2 fl. dr., together with enough water to make the whole measure 1 pint, and put it into bottles.

_Obs._ This preparation is chiefly used as a cosmetic to improve the complexion; and also as a wash for obstinate eruptions and minor glandular swellings and indurations. As a beautifier of the complexion, it is employed by simply wetting the skin with it, either by means of the corner of a napkin or the fingers dipped into it, after which it is gently wiped off with a dry cloth. Dr Paris represents this nostrum to contain 1/2 dr. of corrosive sublimate in every pint, which is not the case.

=Lotion, Granville’s Counter-irritant.= See LINIMENT OF AMMONIA (Compound).

=Lotion, Hem′lock.= _Syn._ LOTII CONII, L. _Prep._ (Mid. Hosp.) Extract of hemlock, 3 dr.; opium, 1 dr.; boiling water, 1 pint; digest until cold, and strain. Anodyne and resolvent; in glandular enlargements, painful ulcers, cancer, indurations, rheumatism, neuralgia, &c.

=Lotion, Hooping-cough.= (Struve’s.) LOTIO ANTIPERTUSSICA, L. _Prep._ (Paris.) Potassio-tartrate of antimony, 1 dr.; tincture of cantharides, 1 oz.; water, 2 oz. This is a powerful counter-irritant, and should be used with caution; as it is apt to induce a troublesome eruption on the parts to which it is frequently applied.

=Lotion of Hydrochlo′′rate of Ammonia.= _Syn._ LOTIO AMMONIÆ HYDROCHLORATIS, L. _Prep._ 1. (WEAKER.) From sal ammoniac, 1 to 4 dr.; water, 1 pint. As a wash in itch, ulcers, tender feet, swelled joints, &c.

2. (STRONGER.) From sal ammoniac, 1 to 2 oz.; water, 1 pint. In contusions, chronic tumours, extravasations, chilblains, &c., when the skin is not broken. Both are stimulant and resolvent or discutient. Vinegar is often substituted for the whole or part of the water, and sometimes a fifth or sixth part of rectified spirit is added. See also LOTION OF CHLORIDE OF AMMONIUM.

=Lotion, Hydrochlo′′ric.= _Syn._ LOTIO ACIDI HYDROCHLORICI, L. _Prep._ 1. Hydrochloric acid, 1 fl. oz.; water, 1 pint. In lepra, and several other skin diseases.

2. (Foy.) Hydrochloric acid, 1 part; water, 16 parts. In chilblains, when the skin is unbroken.

=Lotion, Hydrocyan′ic.= _Syn._ LOTIO HYDROCYANICI, L. ACIDI HYDROCYANICI, L. _Prep._ 1. (Magendie.) Medicinal hydrocyanic acid, 1 to 2 fl. dr.; lettuce water, 1 pint. In hepatic affections.

2. (Sneider.) Medicinal acid, 1-1/2 fl. dr.; rectified spirit and water, of each 6 fl. oz.

3. (A. T. Thomson.) Medicinal acid and rectified spirit, of each 2 fl. dr.; acetate of lead, 16 gr.; distilled water, 7-1/2 fl. oz. In impetigo, &c.

_Obs._ Lotions of prussic acid are employed to allay pain and irritation in various chronic skin diseases, especially the scaly and itchy eruptions; and in cancer, &c., with variable success. See HYDROCYANIC ACID.

=Lotion of Hyposul′phite of Soda.= _Syn._ LOTIO SODÆ HYPOSULPHITIS, L. _Prep._ (Startin.) Hyposulphite of soda and alum, of each 1-1/2 dr.; eau de Cologne, 1/2 fl. oz.; rose water, 7-1/2 fl. oz.; in the advanced stages of acne.

=Lotion of I′odide of Ar′senic and Mer′cury.= _Syn._ LOTIO ARSENICI ET HYDRARGYRI HYDRIODATIS, L. _Prep._ From Donovan’s solution, 1 part; water, 9 parts. In lepra, psoriasis, and other scaly skin diseases. See SOLUTION.

=Lotion of Iodide of Potas′sium.= _Syn._ LOTIO POTASSII IODIDI, L. _Prep._ 1. From iodide of potassium, 1 to 2 dr.; water, 1 pint. In the usual cases in which ioduretted preparations are employed.

2. (Dr O. Ward.) Iodide of potassium, 1 dr.; water, 3/4 pint. In itch. (See _below_.)

=Lotion of Iodide of Zinc.= _Syn._ LOTIO ZINCI IODIDI, L. _Prep._ (Ross.) iodine, 1-1/2 dr.; zinc filings, 1 dr.; water, 8 fl. oz.; digest with heat until the liquid becomes coloured, then filter. In enlarged tonsils.

=Lotion of I′odine.= _Syn._ LOTIO IODINII, L. _Prep._ From iodine, 2 gr.; rectified spirit, 1 fl. dr.; dissolve, well agitate the solution with distilled water, 1 pint, and filter. An excellent wash for scrofulous ulcers, and in chronic ophthalmia, cutaneous scrofula, and several chronic skin diseases, particularly in highly sensitive habits.

=Lotion of Iodine Compound.= _Syn._ LOTIO IODI COMP., L. _Prep._ 1. Iodide of potassium, 80 gr.; iodine, 60 gr.; water, 1 oz.

2. (Cazenave.) Iodide of potassium and iodide of sulphur, of each 1 dr.; water, 1 pint. In itch; either alone or diluted with an equal bulk of water.

3. (Dauvergne.) Iodine, 3 dr.; iodide of potassium, 6 dr.; water, 3 fl. oz.; dissolve, and label the bottle No. 1. Sulphuret of potassium, 4 oz.; water, 8 fl. oz.; dissolve. For use, a teaspoonful of No. 1, and a table-spoonful of No. 2, are to be added to about a pint of water. In itch, and several other skin diseases.

4. (Lugol.) Iodine, 1 to 2 gr.; iodide of potassium, 3 to 6 gr.; water, 1 pint. In scrofulous ophthalmia, fistulas, &c.; and as a wash in numerous skin diseases.

5. (Righini.) Chloride of lime, 4 dr.; water, 2-1/2 fl. oz.; triturate together, filter into a stoppered bottle, and add of tincture of iodine, 1 dr. With a pint of water it forms an effective application in itch.

6. (Soubeiran.) Iodide of potassium, 1 oz.; iodine, 1/2 oz.; water, 6 oz.; dissolve. Used as iodine paint; also as a caustic to touch the surfaces of scrofulous ulcers, and the eyelids in scrofulous ophthalmia.

7. Iodide of potassium, 1/2 dr.; iodine, 16 gr.; water, 1 pint. This is the common and best form of iodine lotion, but for certain purposes it is used much stronger. (See _above_.)

=Lotion of Iron with Conium.= LOTIO FERRI CUM CONIO. Sulphate of iron, 8 gr.; extract of conium, 8 gr.; water, 1 oz.

=Lotion, Itch.= _Syn._ LOTIO ANTIPSORICA, L. _Prep._ (Cazenave.) Sulphuret of potassium, 1 dr.; soft soap, 2 dr.; water, 8 fl. oz.; dissolve. An excellent remedy for the itch. It leaves little smell behind, and does not soil the linen. (See _above_.)

=Lotion, Kirkland’s.= See LOTION OF MYRRH.

=Lotion of Lemon Juice.= _Syn._ LOTIO SUCCI LIMONIS, L. _Prep._ From the freshly expressed juice of lemon, diluted with 4 or 5 times its bulk of water. To render it more agreeable, rose water may be employed, or a few drops of eau de Cologne added. It is cooling and detergent, and forms an excellent application to foul ulcers, and to allay the itching in numerous cutaneous affections.

=Lotion of Lime Wa′ter.= _Syn._ LOTIO CALCIS SPIRITUOSA, L. _Prep._ (Ph. Chirur.) Rectified spirit, 4 oz.; lime water, 8 fl. oz. See EVAPORATING LOTION (_above_.)

=Lotion, Mammil′lary.= _Syn._ LOTIO BALSAMI PERUVIANI COMPOSITA, L. _Prep._ (Iverg.) Balsam of Peru, 1 dr.; yolk of 1 egg; make an emulsion, and add of spirit of wild thyme, 3 fl. oz. For sore nipples; to be followed, whilst still wet, by a ‘dusting’ with a powder composed of Peruvian bark, 1 dr.; gum Arabic, 2 dr.

=Lotion, Mercu′′rial.= _Prep._ 1. (BLACK WASH, BLACK LOTION, MILD PHAGEDENIC L.; LOTIO NIGRA (B. P.), L. HYDRARGYRI CINEREA, L. H. NIGRA, L. H. CHLORIDI CUM CALCE, L. MERCURIALIS N., AQUA PHAGEDÆNICA, MITIS, L.)

_a._ (B. P.) From calomel, 3 gr.; lime water, 1 oz.; well shaken together.

_b._ (Mid. Hosp.) To the last add of thick mucilage, 1 fl. oz.

_c._ (Guy’s Hospital.) From calomel, 1 dr., lime water, 8 fl. oz.

_Obs._ Black wash is a favourite application to all kinds of syphilitic and scrofulous sores. The bottle should be well shaken before the lotion is applied.

2. YELLOW WASH, Y. LOTION, PHAGEDENIC L.; (LOTIO FLAVA, L. PHAGEDÆNICA, AQUA P., LOTIO HYDRARGYRI FLAVA, L. H. BICHLORIDI CUM CALCE, L.)——_a._ (B. P.) Corrosive sublimate, 18 gr.; lime water, 10 oz.; well shaken together.

_b._ (St B. Hosp.) Corrosive sublimate, 20 gr.; lime water, 6 fl. oz. Used as the last, but it is stronger and more active, from containing a little undecomposed bichloride.

=Lotion of Myrrh.= _Syn._ KIRKLAND’S LOTION; LOTIO MYRRHÆ, L. _Prep._ 1. (Dr Kirkland.) Tincture of myrrh and lime water, equal parts. In scorbutic ulcers and gums.

2. (Compound; LOTIO MYRRHÆ COMPOSITA, L.——Ph. Chirur.) Honey of roses and tincture of myrrh, of each 2 fl. dr.; lime water, 2-1/2 fl. oz. As No. 1; also used as a dentifrice.

=Lotion of Ni′trate of Bis′muth.= _Syn._ LOTIO BISMUTHI NITRATIS, L. _Prep._ (Cutan. Hosp.) Subnitrate or trisnitrate of bismuth, 1/2 dr.; corrosive sublimate, 12 gr.; spirit of camphor, 1/2 fl. dr.; water, 1 pint. In itch, and some other eruptions.

=Lotion of Nitrate of Sil′ver.= _Syn._ LOTIO ARGENTI NITRATIS, L. _Prep._ 1. Nitrate of silver, 15 gr.; nitric acid, 10 drops; distilled water, 1/2 pint. As a wash for indolent ulcers, sore legs, &c.

2. (Jackson.) Nitrate of silver, 10 gr.; water, 1 fl. oz. For bed-sores; applied, at first, twice or thrice a day.

3. (Schreider.) Nitrate of silver, 1/2 dr.; nitric acid, 10 drops; water, 1-1/2 fl. oz. In chilblains, soft corns, &c.

=Lotion of Nitrate of Silver (Strong).= LOTIO ARGENTI NITRATIS FORTIS. Nitrate of silver, 60 gr.; distilled water, 1 oz.

=Lotion of Nitrate of Sil′ver, Etherial.= LOTIO ARGENTI NITRATIS ÆTHEREA. Nitrate of silver, 20 gr.; distilled water, 1 dr.; spirit of nitrous ether, 1 oz.

=Lotion of Ni′tre.= _Syn._ LOTIO POTASSÆ NITRATIS, L. _Prep._ 1. Nitre, 3 dr.; vinegar, 1/4 pint; water, 3/4 pint.

2. Nitre, 2 dr.; sal ammoniac, 1 dr.; vinegar and water, of each 1/2 pint. In sprains, contusions, extravasations, tender feet, chilblains, &c. Diluted with an equal bulk of water, it is a popular application to ‘black eyes.’

=Lotion of Ni′tric Acid.= _Syn._ LOTIO ACIDI, L. ACIDI NITRICI, L. _Prep._ 1. (Collier.) Nitric acid, 1/2 fl. oz.; water, 1 pint. In lepra, and other scaly skin diseases.

2. (Phœbus.) Nitric acid, 1 fl. dr.; laudanum, 1-1/2 fl. dr.; rose water, 1/2 pint. For venereal ulcers.

=Lo′tion of Nitromuriat′ic Acid.= _Syn._ LOTION OF AQUA REGIA. _Prep._ (Copland.) Nitromuriatic acid, 1-1/4 dr.; water, 1 pint. In gangrene and mortification.

=Lotion of Nux Vom′ica.= _Syn._ LOTIO NUCIS VOMICÆ, L. _Prep._ 1. Alcoholic extract of nux vomica, 10 gr.; rectified spirit and water, of each 2-1/2 fl. oz. In amaurosis.

2. (Radius.) Alcoholic extract of nux vomica, 8 gr.; liquor of ammonia (stronger), 1/2 fl. oz.; rectified spirit, 2 fl. oz. In paralysed limbs.

=Lotion of O′pium.= _Syn._ LOTIO OPII, L. OPIATA, L. _Prep._ 1. (Christison.) Opium, 40 gr.; water, 1/4 pint; infuse, add to the filtered liquid a solution of sugar of lead, 40, in water, 1/4 pint, and filter.

2. (St B. Hosp.) Opium, 1-1/2 dr.; boiling water, 1 pint; triturate and strain. Anodyne; the first is also refrigerant and discutient.

=Lotion of Ox′ide of Zinc.= _Syn._ LOTIO ZINCI OXYDI, L. _Prep._ 1. (Augustin.) Oxide of zinc, 1 dr.; elder-flower water, 1-1/2 fl. oz. In pustular erysipelas.

2. (Hosp. F.) Oxide of zinc, 1/2 dr.; mucilage, 2 fl. dr.; water, 6 fl. dr. As an astringent and desiccant, in scrofulous eruptions, excoriations, moist chaps, &c.

=Lotion, Phageden′ic.= See MERCURIAL LOTION (_above_).

=Lotion of Phos′phoric Acid.= _Syn._ LOTIO ACIDI PHOSPHORICI, L. _Prep._ (Pereira.) Dilute phosphoric acid (Ph. L.), 1 fl. oz.; water, 1/2 pint. In caries and fistula.

=Lotion of Potas′sa.= See LOTIO POTASSÆ, L. _Prep._ From liquor of potassa, 1 fl. oz.; water, 1 pint. Detergent; in scorbutic eruptions, and foul ulcers, and to prevent infection.

=Lotion of Potas′sio-tar′trate of An′timony.= _Syn._ LOTIO ANTIMONIALIS, L. ANTIMONII POTASSIO-TARTRATIS, L. RUBEFACIENS, L. _Prep._ 1. Tartar emetic, 1 dr.; tincture of camphor, 2 fl. dr.; water, 1 pint. As a local stimulant. Diluted with twice or thrice its weight of water, it is employed as a collyrium in chronic ophthalmia, and in specks on the cornea.

2. (Sir Wm. Blizard.) Tartar emetic, 20 gr.; boiling water, 1 fl. oz. Used to cleanse foul ulcers, to repress fungous growths and warts, and in ringworm, &c.

3. (Pereira.) Tartar emetic, 1 dr.; boiling water, 1-1/2 fl. oz.; dissolve. Employed as a local irritant instead of the ointment. All the above are rubefacient and counter-irritant. See ANTIMONY.

=Lotion of Quin′ine.= _Syn._ LOTIO QUINÆ, EMBROCATIO Q., L. _Prep._ From disulphate of quinine, 1 dr.; rectified spirit, 5 fl. oz. Applied over the spine in intermittents.

=Lotion, Sapona′ceous.= _Syn._ LOTIO SAPONIS, L. SAPONACEA (Ph. L. 1746), L. _Prep._ From liquor of carbonate of potassa, 1/2 oz.; olive oil, 4 oz.; rose water, 12 oz.; agitate together. Emollient; chiefly as a cosmetic.

=Lotion, Saviard’s.= _Prep._ (Foy.) Caustic potassa, 1 dr.; camphor, 20 gr.; sugar, 1 oz.; water, 1 pint. As a wash for indolent ulcers.

=Lotion, Struve’s.= See HOOPING-COUGH LOTION.

=Lotion of Sul′phate of Cop′per.= _Syn._ LOTIO CUPRI SULPHATIS, L. _Prep._ 1. Blue vitriol, 1 dr.; camphor julep, 1 pint. For phagedenic ulcers, and in itch, &c.

2. (Dr Graves.) Sulphate of copper, 10 gr.; water, 1 fl. oz. In chilblains, ringworm, &c.

3. (Lloyd.) Sulphate of copper, 1 oz.; water, 1 pint. In itch; either alone or diluted.

=Lotion of Sul′phate of Iron.= _Syn._ LOTIO FERRI SULPHATIS. Sulphate of iron, 2 gr.; water, 1 oz.

=Lotion of Sul′phate of Zinc.= _Syn._ LOTIO ZINCI SULPHATIS, L. _Prep._ 1. Sulphate of zinc, 3/4 dr.; water, 1 pint. Astringent; in some chronic skin diseases, as a wash for loose, flabby granulations, and for ulcers that discharge profusely, &c.

2. (Collier.) Sulphate of zinc, 2 dr.; water, 1 pint. As a counter-irritant in pains of the joints, periosteum, old sprains, &c.

=Lotion of Sulphuret of Sodium.= (Dr Barlow.) _Syn._ LOTIO SODII SULPHURETI. _Prep._ Sulphide of sodium, 2 dr.; white soap, 2-1/2 dr.; rectified spirit, 2 dr.; lime water, 7 oz. For ringworm.

=Lotion of Tannin.= (Mr Druitt.) _Syn._ LOTIO TANNINI. _Prep._ Tannic acid, 5 gr.; distilled water, 1 oz.; mix. On lint, covered with oil silk, to sore nipples.

=Lotion of Tar.= _Syn._ LOTIO PICIS LIQUIDÆ, L. _Prep._ (Saunders.) Quicklime, 6 oz.; water, 2-1/2 pints; slake, add of tar, 4 oz., and boil to one half. This liquid may be advantageously employed in various chronic skin diseases, especially those affecting the heads of children. See INFUSION OF TAR.

=Lotion of Valer′ian.= _Syn._ LOTIO VALERIANÆ, EMBROCATIO ANTIHYSTERICA, E. EMMENAGOGA, L. _Prep._ From tincture of valerian and proof spirit, equal parts. In hysteria, suppressions, &c.

=Lotion of Vera′trine.= _Syn._ LOTIO VERATRIÆ, L. _Prep._ (Dr Turnbull.) Veratrine, 20 to 60 gr.; rectified spirit, 2 oz. In gout, rheumatism, &c. It is extremely poisonous, and must only be used where the skin is sound, and then with great caution.

=Lotion of Ver′digris.= _Syn._ LOTIO ÆRUGINIS, L. CUPRI CITRATIS, L. _Prep._ From verdigris, 3 dr.; vinegar, 1/4 pint; water, 3/4 pint. As a wash for indolent, scrofulous, and venereal ulcers.

=Lotion of Vin′egar.= See ACETIC LOTION (_above_).

=Lotion, Yellow.= See MERCURIAL LOTION (_above_).

=LOUSE.= _Syn._ PEDICULUS. There are several species of this offensive parasite infesting the bodies of man and domesticated animals. The three varieties of lice found on the human skin are:——(1) The _Pediculus corporis_, (2) the _P. capitis_, (3) the _P. pubis_.

(1.) The _P. corporis_, the body louse, is of a dirty white colour, and varies from half to two lines in length. Its body is broad and elongated, with the margins divided into lobes, and covered with minute hairs; but it has a narrow thorax, furnished on each side with three legs, which terminate in claws. This creature produces great irritation of the skin, giving rise to a number of little pimples on it, which frequently discharge a watery fluid. It multiplies with extraordinary rapidity.

(2.) The _P. capitis_, the head louse, is much smaller than the above. It is devoid of hairs, with legs large in proportion to its body. It gives rise to a very troublesome eruption, attended with a watery discharge. It is propagated by means of the ova or nits, which are glued to the hairs of the head.

(3.) The _P. pubis_, the crab louse, is a small, round variety, which attaches itself with considerable tenacity to the hairs of the stomach and lower part of the body more particularly, and, like the preceding parasite, glues its eggs to the hairs.

Various applications have been recommended for the destruction of these loathsome parasites; amongst which we may mention sulphur, stavesacre, white precipitate, and cocculus indicus, in the form of ointments; carbolic acid and perchloride of mercury lotions, and tobacco. Benzoic acid has been found of service in allaying the irritation. Diligent washing with soap and water should be had recourse to previous to applying any of the above remedies, and should the head be infested, the hair should be cut short, and frequently combed with a small toothcomb.

Pediculi are sometimes conveyed from filthy to cleanly persons by means of dirty water-closets, chairs, sheets, brushes and combs, and in various other ways.

School children frequently obtain them in consequence of their heads being brought into too close contact with the heads of other children infested by them.

=LOZ′ENGE.= _Syn._ TROCHE; TROCHISCUS, TABELLA, L.; TABLETTE, Fr. A small cake, often medicated, consisting principally of powdered sugar, made into a mass with some glutinous liquid, without the aid of heat, and dried. The form given to lozenges (TROCHE, TABELLÆ, TROCHISCI, TABLETTES) is generally that of a small round tablet or flattened cylinder; but originally they were exclusively made in the shape of a lozenge or rhomb, from which circumstance their familiar name is derived. LOZENGES are distinguished from DROPS OR PASTILLES by the non-employment of heat in their preparation; and from PASTES, by the latter being formed of vegetable juice or pulp, and having a softer consistence.

In the preparation of lozenges the dry ingredients, separately reduced to a very fine powder, are first perfectly mixed together, and then beaten into a stiff paste with the glutinous liquid employed to give them form; the mass is next rolled out to a desired thickness, and cut into pieces of the proper shape by means of a small cylinder or punch of steel or tin-plate, called a ‘lozenge-cutter.’ The newly formed lozenges are lastly dried by placing them on an inverted sieve or frame covered with paper in a dry, warm, and airy situation, and are frequently turned until they become hard and brittle, due care being taken to preserve them from dust and dirt. To prevent the mass adhering to the fingers and utensils during the process of manufacture, a little finely powdered starch, or a very little olive oil, scented with the same aromatic as that contained in the lozenges, may be used. Mucilage of gum Arabic or of gum tragacanth, thin isinglass size, or the strained white of egg, are the substances usually employed to make the pulverulent materials adhere together. A strained decoction of Irish moss is now frequently used for the same purpose, for inferior qualities. The larger the proportion of gum which enters into the composition of lozenges, the slower they dissolve in the mouth; hence powdered gum is frequently added to the other materials to increase their quality in this respect, as well as to give an additional solidity to those which, like chalk, for instance, are of a peculiarly dry or crumbly nature. Starch and potato flour are often added to lozenge-masses in lieu of a portion of the sugar, and even plaster of Paris is not unfrequently employed to give them weight; frauds which are readily detected in the manner noticed under GUM and SUGAR.

As a general rule, MEDICATED LOZENGES should weigh from 8 to 10 gr. each, and a medium dose of their active ingredient should be distributed through the bulk of 6 to 8 of them, in which case 3 to 5 of them may be safely taken as a dose, or sucked during the lapse of 3 or 4 hours. This will be useful in the preparation of those for which no established proportions are given. In ‘sending out’ compounds of this class containing active medicaments, as morphia or opium, the retailer as well as the manufacturer should be careful that the quantity contained in each lozenge is plainly marked on the label.

In lozenges intended for MOUTH COSMETICS or to perfume the breath, ambergris is generally regarded as the most appropriate perfume; but hard smokers frequently prefer cloves and cinnamon, and some ladies give the preference to roses, orange flowers, and orris or violets.

Lozenges are coloured with the same stains as are used for liqueurs and sweetmeats.

Lozenges, as well as all other similar articles of confectionery, should be preserved in well-closed glass bottles, or jars, or in tin canisters, so as to be perfectly excluded from the air and damp.

=Lozenges, Absor′bent.= TROCHISCI ANTACIDI, L. _Prep._ 1. Take of precipitated chalk, 1/4 lb.; gum Arabic, 2 oz.; double refined white sugar, 14 oz.; all in impalpable powder; oil of nutmeg, 1/2 fl. dr.; pass the mixture through a fine sieve, beat it up with mucilage q. s., roll the mass into a thin sheet, and cut it into lozenges; lastly, dry them by exposing them on a sheet of white paper to the air, out of contact with dust.

2. As the last, but substituting heavy carbonate of magnesia, 1-1/2 oz., for an equal weight of chalk. In diarrhœa, heartburn, acidity, &c. See LOZENGES, CHALK, MAGNESIA, L., SODA, &c.

=Lozenges, Aca′cia.= See LOZENGES, GUM.

=Lozenges, Acid′ulated.= _Syn._ ACIDULATED LEMON LOZENGES, TARTARIC ACID L.; TROCHISCI ACIDI TARTARICI (Ph. E.), L. _Prep._ From tartaric acid, 2 dr.; oil of lemon, 10 drops; white sugar, 8 oz.; mucilage, q. s. to make a lozenge mass. The same ingredients mixed with heat form ACIDULATED or ACID DROPS. Both are useful in coughs, hoarseness, sore throats, &c. See LOZENGES, CAYENNE, CITRIC ACID, ROSE, &c.

=Lozenges, Al′kaline.= See LOZENGES, SODA, VICHY, &c.

=Lozenges, A′lum.= _Syn._ TROCHISCI ALUMINIS, L. Each lozenge contains 1-1/2 gr. of alum. As an astringent. See LOZENGES, ASTRINGENT.

=Lozenges, An′iseed.= _Syn._ TROCHISCI ANISI, L. _Prep._ From oil of aniseed, 1-1/2 fl. dr.; finest white sugar, 1 lb.; mucilage, q. s. Carminative and stomachic. In colic, griping, &c.; and as a pectoral.

=Lozenges, Anthelmin′tic.= See LOZENGES, WORM.

=Lozenges, Antimonial.= _Syn._ TROCHISCI ANTIMONIALES, MORSULI STIBII KUNKELII, L.; TABLETTES DE KUNKEL, Fr. _Prep._ (P. Cod.) Levigated sulphuret of antimony and cardamom seeds, of each 1 oz.; almonds (blanched), 2 oz.; cinnamon, 1/2 oz.; sugar, 13 oz.; mucilage of tragacanth, q. s.; to be divided into 15-gr. lozenges. As an alterative.

=Lozenges, Ape′′rient.= _Syn._ TROCHISCI APERIENTES, L. Each lozenge contains 1 gr. each of calomel and scammony, and 2 gr. of jalap; or, instead of the last, 1/4 gr. of jalapine. 2 to 3 for a dose.

=Lozenges, Astrin′gent.= _Syn._ TROCHISCI ASTRINGENTES, L. Each lozenge contains 1-1/2 gr. of alum and 2 gr. of catechu. In spitting of blood, relaxed uvula, sore throat, &c. See LOZENGES, ALUM.

=Lozenges, Bark.= _Syn._ TROCHISCI CINCHONÆ, L. _Prep._ (P. Cod.) Cinchona, 2 oz.; cinnamon, 2 dr.; white sugar, 14 oz.; mucilage of gum tragacanth, q. s.; mix, and divide into 16-gr. lozenges. Tonic.

=Lozenges, Bath.= _Syn._ DAWSON’S LOZENGES. From extract of liquorice and gum Arabic, of each 1-1/2 oz.; sugar, 17 oz. It is both rolled into lozenges and formed into pipes. Demulcent; in tickling coughs, &c.

=Lozenges, Benzoic Acid.= (Th. Hosp.) _Syn._ TROCHISCI ACIDI BENZOICI. _Prep._ Benzoic acid in powder, 175 gr.; tragacanth in powder, 70 gr.; refined sugar in powder, 280 gr.; red currant paste, a sufficient quantity to make 1 lb. Divide into 350 lozenges, and dry at a moderate heat in a hot-air chamber. A valuable stimulant and voice lozenge in nervomuscular weakness of the throat.

=Lozenges, Bicarbonate of Soda.= TROCHISCI SODÆ BICARBONATIS. Bicarbonate of soda, in powder, 3600 gr. (8-1/4 oz.); refined sugar, 25 oz.; gum acacia, in powder, 1 oz.; mucilage, 2 oz.; distilled water, 1 oz.; mix, and form in 720 lozenges. Each lozenge contains 5 gr. of bicarbonate of soda.——_Dose_, 1 to 6 lozenges.

=Lozenges, Bis′muth.= _Syn._ TROCHISCI BISMUTHI, L. _Prep._ 1. (B. P.) Subnitrate of bismuth, 346 gr.; carbonate of magnesia, 4 oz.; precipitated chalk, 6 oz.; sugar, 29 oz.; gum acacia, 1 oz.; mucilage, 2 oz.; rose water, a sufficiency; make 720 lozenges. Each lozenge contains 2 gr. of subnitrate of bismuth.——_Dose_, 1 to 6 lozenges.

2. (Trousseau.) Each lozenge contains 1 gr. of subnitrate of bismuth. Tonic and antispasmodic; in chronic dyspepsia, gastrodynia, nausea, cramp of the stomach, &c.

=Lozenges, Black Cur′rant.= TROCHISCI RIBIS NIGRI, L. _Prep._ From inspissated juice of black currants and sugar, of each, in powder, 1 lb.; tartaric acid, 1/4 oz.; mucilage, q. s. In hoarseness, &c.

=Lozenges, Bo′′rax.= _Syn._ TROCHISCI BORACIS, L. Each lozenge contains 3 gr. of borax. One occasionally in aphthous sore mouth, sore throat, &c.

=Lozenges, Bromide of Ammonium.= Each lozenge contains 2 gr. of bromide of ammonium.——_Dose_, 1 to 3 lozenges. In hooping-cough.

=Lozenges, Burnt Sponge.= _Syn._ TROCHISCI SPONGIÆ, T. S. USTÆ, L. _Prep._ (P. Cod.) Burnt sponge, 4 oz.; sugar, 12 oz.; mucilage of tragacanth, q. s.; divide into 12-gr. lozenges. In scrofula, glandular enlargements, &c.

=Lozenges, Caca′o.= _Syn._ TROCHISCI BUTYRI CACAO, L. Each lozenge contains 1-3rd of its weight of pure cacao butter. In habitual constipation; and in phthisis, scrofula, &c., instead of cod-liver oil; taken _ad libitum_. They are usually scented with roses.

=Lozenges, Caffe′ine.= _Syn._ TROCHISCI CAFFEINÆ, L. Each lozenge contains 1/4 gr. of caffeine and 1/2 gr. of citric acid. In hemicrania, hypochondriasis, &c.

=Lozenges, Cal′omel.= _Syn._ WORM LOZENGES; TROCHISCI CALOMELANOS, T. HYDRARGYRI CHLORIDI, L. _Prep._ (P. Cod.) Each lozenge contains 1 gr. of calomel. Alterative, &c. They afford a simple way of introducing mercury into the system. During their use salt food and acid liquors should be avoided. When given for worms they should be followed, in a few hours, by a purge.

=Lozenges, Cam′phor.= _Syn._ TROCHISCI CAMPHORÆ, L. Each lozenge contains 3/4 gr. of (finely powdered) camphor. They must be kept in a well-corked bottle.

=Lozenges of Carbolic Acid.= (Th. Hosp.) _Syn._ TROCHISCI ACIDI CARBOLICI. _Prep._ Carbolic acid, 350 gr.; gum Arabic, 220 gr.; refined sugar, 12-1/2 oz.; mucilage, 1 oz.; distilled water q. s. to make 1 lb. Divide into 350 lozenges, and finish as with benzoic acid lozenges.

=Lozenges, Car′bonate of Lime.= See LOZENGES, CHALK.

=Lozenges, Cat′echu.= _Syn._ CACHOU LOZENGES; TROCHISCI CATECHU (B. P.), T. DE TERRA JAPONICA, L.; TABLETTES DE CACHOU, Fr. _Prep._ 1. (Ph. E. 1744.) Catechu, 2 oz.; tragacanth, 1/2 oz.; white sugar, 12 oz.; rose water, q. s.

2. (P. Cod.) Extract of catechu, 4 oz.; sugar, 16 oz.; mucilage of gum tragacanth q. s.; for 10-gr. lozenges.

3. (TRO. CATECHU ET MAGNESIÆ——P. Cod.) Magnesia, 2 oz.; powdered catechu, 1 oz.; sugar, 13 oz.; mucilage of gum tragacanth (made with cinnamon water), q. s. to mix.

4. (PERFUMED.) See CACHOU AROMATISÉ and PASTILS.

5. (B. P.) Pale catechu, in powder, 720 gr.; refined sugar, in powder, 25 oz.; gum Arabic, in powder, 1 oz.; mucilage, 2 oz.; distilled water, a sufficiency; divide into 720 lozenges. Each lozenge contains 1 gr. of catechu.——_Dose_, 1 to 3 lozenges.

_Obs._ All the above are taken in diarrhœa, in relaxation of the uvula, in irritation of the larynx, and as cosmetics to fasten the teeth, and disguise a fetid breath. The one containing magnesia (No. 3) is also sucked in dyspepsia, acidity, and heartburn.

=Lozenges, Cayenne′.= _Syn._ TROCHISCI CAPSICI, L. Flavoured with essence or tincture of capsicum or cayenne, with a very concentrated Chili vinegar, or a little pure soluble cayenne pepper.

2. (ACIDULATED.) To each lb. add of tartaric acid, 1/2 oz. Both are used in dyspepsia, and to promote digestion and create an appetite. They have also been recommended in temporary deafness arising from exposure to cold. They are generally tinged of a light pink or red colour.

=Lozenges, Chalk.= _Syn._ HEARTBURN LOZENGES; TROCHISCI CRETÆ; (Ph. E.), T. CARDIALGICI, TABELLÆ CARDIALGICÆ, L. _Prep._ (Ph. E.) Prepared chalk, 4 oz.; gum Arabic, 1 oz.; nutmeg, 1 dr.; white sugar, 6 oz.; rose or orange-flower water, q. s. Antacid and absorbent. 3 or 4 sucked _ad libitum_; in heartburn, dyspepsia, diarrhœa, acidity of the stomach and bowels, &c.

=Lozenges, Char′coal.= _Syn._ TROCHISCI CARBONIS, L. _Prep._ 1. (P. Cod.) Prepared charcoal, 4 oz.; white sugar, 12 oz., mucilage, q. s. to mix. In diarrhœa, cholera, dyspepsia, &c.

2. (TRO. CARBONAS CUM CHOCOLAT——M. Chevallier.) Charcoal and white sugar, of each 1 oz.; chocolate, 3 oz.; mucilage of gum tragacanth, q. s. to mix. Nutritious; used as the last.

=Lozenges, Ching’s Worm.= _Prep._ 1. (YELLOW.) From saffron, 1/2 oz.; boiling water, 1 pint; infuse, strain, add, of calomel, 1 lb.; powdered white sugar, 28 lbs.; mix well, make a mass with mucilage of tragacanth, and divide it into 7000 lozenges. Each lozenge contains 1 gr. of calomel.

2. (BROWN.) From calomel, 7 oz.; resinous extract of jalap, 3-1/2 lbs.; white sugar, 10 lbs.; mucilage of tragacanth, q. s.; mix, and divide into 6125 lozenges. Each lozenge contains 1/2 gr. of calomel and 3-1/2 gr. of resinous extract of jalap. 1 to 6 of the yellow lozenges over night, as a vermifuge, followed by an equal number of the brown ones the next morning fasting.

=Lozenges, Chlo′′rate of Potassa.= _Syn._ TROCHISCI POTASSÆ CHLORATIS, L. _Prep._ 1. Each lozenge contains 1-1/2 gr. of chlorate of potassa. In phthisis, sore throat, &c. 6 to 12 a day.

2. (B. P.) Chlorate of potash, in powder, 3600 gr. (8-1/4 oz.); refined sugar, in powder, 25 oz.; gum acacia, in powder, 1 oz.; mucilage, 2 oz., distilled water, 1 oz., or a sufficiency; mix the powders, and add the mucilage and water to form a proper mass; divide in 720 lozenges. Each lozenge contains 5 gr. of chlorate of potash.——_Dose_, 1 to 6 lozenges.

=Lozenges, Chloride of Ammonium.= Each lozenge contains 2 to 3 gr. of chloride of ammonium. Used in bronchitis.——_Dose_, 2 to 4 lozenges.

=Lozenges, Chlo′′ride of Gold.= 1. (TROCHISCI AURI CHLORIDI, L.) Each lozenge contains 1/40 gr. of neutral chloride of gold. 2 to 4 daily; in scrofula, cancer, &c.

2. (With SODA; TROCHISCI AURI ET SODII CHLORIDI, T. SODII AURO-CHLORIDI, L.——Chrestien.) Each lozenge contains 1/16th gr. of soda-chloride of gold. Two daily; as the last.

=Lozenges, Chloride of Lime.= _Syn._ TROCHISCI CALCIS CHLORIDI, T. C. CHLORINATÆ, L. Each lozenge contains 1/4 gr. of dry chloride of lime. They are frequently tinged with a little carmine. Used to sweeten the breath and whiten the teeth. They do not keep well.

=Lozenges of Chlorinated Soda.= _Syn._ TROCHISCI SODÆ CHLORINATÆ. _Prep._ Solution of chloride of soda, 1 fl. dr.; sugar, 10 dr.; gum Arabic, 2 dr.; mucilage of tragacanth, q. s. (1/2 dr. of camphor may be added). To be held in the mouth during infection.

=Lozenges, Choc′olate.= _Syn._ TROCHISCI CHOCOLATÆ, L. From vanilla chocolate pressed into sheets, and cut into pieces whilst hot.

=Lozenges, Cincho′na.= _Syn._ TROCHISCI CINCHONÆ EXTRACTI, L. Each lozenge contains 1-1/2 gr. of dry extract of bark. A little cinnamon or nutmeg is often added. See BARK LOZENGES.

=Lozenges, Cin′namon.= _Syn._ TROCHISCI CINNAMONI, L. From cinnamon (in fine powder), 1 oz., or the essential oil, 1 fl. dr., to each lb. of sugar. Carminative and stomachic. CASSIA LOZENGES are made in the same way, and are frequently substituted for them.

=Lozenges, Ci′trate of Iron.= _Syn._ TROCHISCI FERRI CITRATIS, L. Each lozenge contains 1-1/2 gr. of ammonio-citrate of iron. As a mild chalybeate tonic. They are sometimes made with equal parts of sugar and vanilla chocolate.

=Lozenges, Citrate of Magne′sia.= _Syn._ TROCHISCI MAGNESIÆ CITRATIS, L. Each 15-gr. lozenge contains 5 gr. of pure citrate of magnesia. Laxative.

=Lozenges, Cit′ric Acid.= _Syn._ TROCHISCI ACIDI CITRICI, L. _Prep._ (P. Cod.) Citric acid, 3 dr.; sugar, 16 oz.; essence of lemon, 16 drops; mucilage of tragacanth, q. s.; mix, and divide into 12-gr. lozenges. In coughs, hoarseness, &c.

=Lozenges, Clove.= _Syn._ TROCHISCI CARYOPHILLI, L. From cloves (powdered along with sugar), 2 oz., or essential oil, 1 fl. dr., to each lb. of sugar. They are frequently coloured. Carminative and stomachic; also used as a restorative after fatigue, added to chocolate to improve its flavour, and sucked to sweeten the breath.

=Lozenges, Cough.= _Syn._ PECTORAL LOZENGES, PULMONIC L.; TROCHISCI ANTICATARRHALES, L. _Prep._ 1. Black-currant lozenge-mass, 1 lb.; ipecacuanha (in very fine powder), 2 dr. For 12-gr. lozenges.

2. To the last add of powdered opium and camphor, 1-1/2 dr.

3. To either No. 1 or 2 add of oil of aniseed, 1-1/2 fl. dr.

4. (TABLETTES DE TRONCHIN.) From powdered gum Arabic, 8 oz.; oil of aniseed, 16 drops; extract of opium, 12 gr.; kermes mineral, 1 dr.; pure extract of liquorice, 2 oz.; white sugar, 32 oz.; water, q. s.; mix, and divide into 10-gr. lozenges.

5. (TABLETTES DE VANDAMME.) From benzoic acid, 1 dr.; orris powder, 2 dr.; gum Arabic (powdered), 1 oz.; starch, 2 oz.; sugar, 16 oz.; water, q. s.; mix and divide into 15-gr. lozenges.

6. Each lozenge contains 1/2 gr. of lactucarium, 1/8 gr. of powdered ipecacuanha, and 1/12 gr. of powdered squills, together with 1/3rd of their weight of pure extract of liquorice.

_Obs._ To render the above serviceable in coughs, hoarseness, &c., the bowels should be kept gently open with some mild aperient, and a light diet adopted, with abstinence from stimulating liquors. See LOZENGES, EMETINE, IPECACUANHA, &c.

=Lozenges, Cro′ton Oil.= _Syn._ TROCHISCI CROTONIS, L. _Prep._ (Soubeiran.) Croton oil, 5 drops; powdered starch, 40 gr.; white sugar, 1 dr.; chocolate, 2 dr.; divide into 30 lozenges; 5 or 6 generally prove cathartic.

=Lozenges, Cu′bebine.= _Syn._ TROCHISCI CUBEBINI, L. _Prep._ (Ph. Hamb.) Copaiba and extract of cubebs, of each 6 oz.; yolks of 3 eggs; mix, add of powdered marshmallow root, 6 oz.; make it into pipes of 12 gr. each, and roll them in sugar. In gleet, &c., and in affections of the mucous membranes of the throat and fauces. Lablonye orders them to be made of sugar, and flavoured with oil of peppermint.

=Lozenges, Cu′bebs.= _Syn._ TROCHISCI CUBEBÆ, L. _Prep._ 1. (Spitta.) Cubebs, 2 dr.; balsam of tolu, 6 gr.; mix, and add of extract of liquorice, 1 oz.; syrup of tolu, 1 dr.; powdered gum, q. s.; divide into 10-gr. lozenges. One of these, allowed to melt gradually in the mouth, is said to alleviate the obstruction in the nose, in coryza.

2. (U. S.) _Prep._ Oleoresin of cubebs, 1/2 fl. oz. o. m.; oil of sassafras, 1 fl. dr.; extract of liquorice in powder, 4 oz.; gum Arabic in powder, 3 oz.; sugar in fine powder, 3 oz.; syrup of tolu, q. s. Divide into 480 lozenges.

=Lozenges of Cyanide of Gold.= (Chrestien.) _Syn._ TROCHISCI AURI CYANIDI. _Prep._ Cyanide of gold, 2 gr.; chocolate paste, 1 oz. Made into 24 lozenges. From 1 to 4 in the day.

=Lozenges, D′Arcet’s.= See LOZENGES, VICHY.

=Lozenges, Diges′tive.= See LOZENGES, RHUBARB, GINGER, CANDY, DIGESTIVE, &c.

=Lozenges, Edinburgh.= _Prep._ From extract of poppies, 2 oz.; powdered tragacanth, 4 oz.; sugar, 10 oz.; rose water, q. s. to form a lozenge-mass.

=Lozenges, Emet′ine.= _Syn._ TROCHISCI EMETINÆ, L. _Prep._ (Magendie.)——1. From impure or coloured emetine, 32 gr. (or pure emetine, 8 gr.); white sugar, 2 oz.; mucilage, q. s. to mix; divide into 64 lozenges. Emetic.——_Dose_, 1 for a child, and 4 for an adult. They are generally tinged of a pink colour with carmine.

2. From impure or coloured emetine, 32 gr. (or pure emetine, 8 gr.); sugar, 4 oz.; mucilage, q. s.; divide into 256 lozenges. Pectoral. One every hour, or oftener, for an adult. The last are intended to take the place of ipecacuanha lozenges, but are rather stronger.

=Lozenges, Escharot′ic.= _Syn._ TROCHISCI ESCHAROTICI, L. _Prep._ (P. Cod.) Corrosive sublimate, 2 dr.; starch, 4 dr.; mucilage of tragacanth, q. s.; mix, and divide into 3-gr. oat-shaped granules. For external use only. See CAUSTIC (Zinc).

=Lozenges, Ferrocy′anide of Iron.= _Syn._ TROCHISCI FERRI FERROCYANIDI, T. CÆRULEI, L. Each lozenge contains 1-1/2 gr. of pure Prussian blue. Alterative, febrifuge, and tonic; in epilepsy, intermittents, diseases of the ganglionic system, &c.

=Lozenges, Fruit.= _Prep._ From juice of black currants (boiled to the consistence of an extract), 1 lb.; juice of red currants (similarly treated), 1/2 lb.; powdered gum tragacanth, 1/4 lb.; sugar, 3 lbs.; raspberry syrup, q. s.; pear essence, a few drops. Resemble black currant lozenges, but are more agreeable.

=Lozenges, Garana′.= See LOZENGES, PAULLINIA.

=Lozenges, Gin′ger.= _Syn._ TROCHISCI ZINGIBERIS, L. _Prep._ From the best unbleached Jamaica ginger and gum Arabic, of each, in very fine powder, 1-1/2 oz.; double refined lump sugar, 1 lb.; rose water (tinged with saffron), q. s. A still finer quality may be made by using an equivalent proportion of essence of ginger, instead of the powder. Inferior qualities are prepared with coarser sugar to which some starch is often added. Ginger lozenges are carminative and stomachic, and are useful in flatulency, loss of appetite, &c.

=Lozenges, Gold.= _Syn._ TROCHISCI AURI, L. Each lozenge contains 1/16 gr. of pulverulent gold.

=Lozenges, Gum.= _Syn._ TROCHISCI ACACIÆ (Ph. E.), T. GUMMI ARABICI, T. GUMMOSI, L. _Prep._ 1. (Ph. E.) Gum Arabic, 4 oz.; starch, 1 oz.; white sugar, 12 oz. (all in very fine powder); rose water, q. s.

2. (P. Cod.) Gum Arabic, 1 lb.; sugar, 3 lbs.; orange-flower water, 2 fl. oz.

3. (Transparent.) From the same materials, but employing a gentle heat. Demulcent; used to allay tickling coughs.

=Lozenges, Guaiacum.= (Th. Hosp.) _Syn._ TROCHISCI GUAIACI. _Prep._ Guaiacum resin in powder, 700 gr.; tragacanth, 70 gr.; sugar, 280 gr.; black currant paste, q. s. Divide into 350 lozenges, and finish as benzoic acid lozenges.

=Lozenges, Gum Tra′gacanth.= _Syn._ TROCHISCI TRAGACANTHÆ, T. GUMMI T., L. _Prep._ (Ph. E. 1744.) Compound powder of tragacanth, 3 oz.; sugar, 12 oz.; rose water, 4 fl. oz. Resemble the last, but are more durable in the mouth.

=Lozenges, Heart′burn.= See LOZENGES, CHALK, &c.

=Lozenges, Iceland Moss.= _Syn._ TROCHISCI LICHENIS, L. (P. Cod.) Contain half their weight of dried and powdered lichen jelly. Resemble gum lozenges.

=Lozenges, Indian Hemp.= _Syn._ TROCHISCI CANNABIS, D. C. INDICI, L. (Ebriard.) Each lozenge contains 1/12 gr. of extract of Indian hemp.

=Lozenges, I′odide of Iron.= _Syn._ TROCHISCI FERRI IODIDI, L. Each lozenge contains 1/2 gr. of dry iodide of iron. 12 to 20 daily; in amenorrhœa, chlorosis, scrofulous debility, &c. They are generally flavoured with a little nutmeg or cinnamon.

=Lozenges, Iodide of Potassium.= _Syn._ TROCHISCI POTASSI IODIDI, L. Each lozenge contains 1 gr. of iodide of potassium, flavoured with nutmeg or cinnamon. 10 to 15 daily; in scrofula, indurations, &c. One of the best ways of taking iodide of potassium.

=Lozenges, Ipecacuan′ha.= _Syn._ TROCHISCI IPECACUANHÆ;, L. _Prep._ 1. (B. P.) Mix ipecacuanha in powder, 180 gr.; refined sugar in powder, 25 oz.; gum acacia in powder, 1 oz.; add mucilage of acacia, 2 fl. oz., and distilled water, 1 oz., or sufficient to form a proper mass. Divide into 720 lozenges, and dry in a hot-air chamber with a moderate heat. Each lozenge contains 1/4 gr. of ipecacuanha.

2. (P. Cod., Hamb. do., and Ph. U. S.) Each lozenge contains 1/4 gr. of ipecacuanha.

3. (TRO. IPECAC. CUM CAMPHORÂ.) Each lozenge contains 1/2 gr. of camphor, and 1/4 gr. of ipecacuanha.

4. (TRO. IPECAC. CUM CHOCOLAT——P. Cod.) Each lozenge contains 1 gr. of ipecacuanha, and 12 gr. of chocolate _à la vanilla_. The above are pectoral and expectorant, and are very useful in tickling and chronic coughs, hoarseness, &c.

=Lozenges, Ipecacuanha and Morphia.= _Syn._ TROCHISCI IPECACUANHÆ ET MORPHIÆ (B. P.). Each lozenge contains 1/12 gr. ipecacuanha and 1/36 gr. hydrochlorate morphia.——_Dose_, 1 to 6 lozenges. See LOZENGES, MORPHIA AND IPECACUANHA.

=Lozenges, I′ron.= _Syn._ TROCHISCI FERRI, T. CHALYBEATI, L. 1. Each lozenge contains 1 gr. of Quevenne’s iron. See LOZENGES, REDUCED IRON.

2. (TRO. FERRI CARBONATIS.) Each lozenge contains 1-1/2 gr. of saccharine carbonate of iron. They are both mild and excellent chalybeates. See LOZENGES, STEEL.

=Lozenges, Ju′jube.= See PASTE, JUJUBE.

=Lozenges, Ker′mes Mineral.= _Syn._ TROCHISCI KERMETIS, L. _Prep._ 1. (P. Cod.) Each lozenge contains 1/6 gr. of kermes mineral, and about 3/4 gr. of gum, made up with sugar and orange-flower water. Diaphoretic and expectorant.

2. (Compound.) As the last, but with the addition of 1/6 gr. of opium, 1/4 gr. of squills, and 1/2 gr. of ipecacuanha. Anodyne and expectorant; both are very useful in catarrhs.

=Lozenges, Lactate of Iron.= _Syn._ TROCHISCI FERRI LACTATIS, L. _Prep._ (Cap.) Each lozenge contains 1 gr. of lactate of iron. Tonic. Useful in debility, accompanied with a diseased state of the organs of digestion.

=Lozenges, Lac′tic Ac′id.= _Syn._ TROCHISCI ACIDI LACTICI, L. Each lozenge contains 1 gr. of lactic acid to about 12 gr. of sugar. They are best flavoured with vanilla or nutmeg. In dyspepsia, &c., especially in gouty subjects. Those prepared by Magendie’s formulæ contain a larger proportion of acid, but are much too sour for frequent use.

=Lozenges, Lactuca′′rium.= _Syn._ TROCHISCI LACTUCARII, L. _Prep._ (Ph. E.) Prepared with lactucarium in the same manner as the opium lozenges, Ph. E. Each of these lozenges contains from 1/6 to 1/7 gr. of lactucarium. Anodyne and demulcent. Used to allay tickling coughs, &c.

=Lozenges, Lavender.= _Syn._ TROCHISCI LAVANDULÆ, L. From 3/4 fl. dr. of Mitcham oil of lavender to each lb. of sugar, and tinged red with liquid lake or carmine; or violet, with litmus or indigo. Used chiefly to scent the breath. Those of the shops are generally deficient in odour.

=Lozenges, Lem′on.= _Syn._ TROCHISCI LIMONIS, T. LIMONUM, L. _Prep._ 1. From 1-1/2 fl. dr. of oil of lemon to each lb. of double refined white sugar.

2. (Acidulated.) See LOZENGES, CITRIC and TARTARIC.

_Obs._ Lemon lozenges and drops are agreeable sweetmeats, and those that are acidulated are often very useful to promote expectoration in coughs, &c. The last are also made into drops as well as lozenges, when they form the ‘ACIDULATED LEMON DROPS’ of the shops. Those that are made of citric acid are by far the most wholesome. Both lemon lozenges and drops are generally coloured with infusion of saffron or turmeric.

=Lozenges, Lettuce.= _Syn._ TROCHISCI LACTUCÆ, L. _Prep._ From extract of lettuce, extract of liquorice, gum, and sugar, equal parts. Anodyne and demulcent; in obstinate cough without expectoration. See LOZENGES, LACTUCARIUM.

=Lozenges, Lichen.= See LOZENGES, ICELAND MOSS.

=Lozenges, Liquorice.= _Syn._ BLACK LOZENGES; TROCHISCI GLYCYRRHIZÆ, T. G. GLABRÆ, T. BECHICI NIGRI, L. _Prep._ 1. (Ph. E.) Extract of liquorice and gum acacia, of each 6 oz; white sugar, 12 oz.; dissolve in water, q. s.; evaporate into a paste, and form into lozenges. Pectoral and demulcent. Useful to allay tickling coughs and remove hoarseness.

2. (With OPIUM.) See LOZENGES, OPIUM.

=Lozenges, Magne′sia.= _Syn._ HEARTBURN LOZENGES; TROCHISCI MAGNESIÆ (Ph. E.), L. _Prep._ 1. (Ph. E.) Carbonate of magnesia, 6 oz.; powdered white sugar, 3 oz.; oil of nutmeg, 20 drops; mucilage of tragacanth, q. s. to mix.

2. (Ph. U. S.) Calcined magnesia, 4 oz.; sugar, 12 oz.; nutmeg, 1 dr.; mucilage of tragacanth, q. s.; for 10-gr. lozenges.

3. (Wholesale.) Calcined magnesia, 3 oz.; powdered gum tragacanth, 1 oz.; double refined lump sugar, 3/4 lb.; rose or orange-flower water, q. s. to make a lozenge mass.

_Obs._ Magnesia lozenges are very useful in heartburn, acidity, and indigestion. The confectioners generally omit the nutmeg, and make their mucilage with either rose or orange-flower water, or else add the dry gum to the mass, and then mix up the powders with one or other of these liquids. It is also an improvement to use calcined magnesia, which is about twice as strong as the carbonate, and consequently less need be employed.

=Lozenges, Manna.= _Syn._ TROCHISCI MANNÆ, L. _Prep._ (Van Mons.) Powdered tragacanth, 1 dr.; white sugar, 12 oz.; manna, 3 oz.; orange-flower water, q. s. to mix. Demulcent, and in large numbers slightly laxative.

=Lozenges, Marshmallow.= _Syn._ TROCHISCI ALTHÆÆ, L.; TABLETTES DE GUIMAUVE, Fr. _Prep._ (P. Cod.) Marshmallow root (decorticated and finely powdered), 2 oz.; sugar, 14 oz.; mucilage of tragacanth (made with orange-flower water), q. s. Demulcent and expectorant. Useful to allay the irritation in cough, &c. The preparations of marshmallow have always been highly esteemed as pectorals by the vulgar.

=Lozenges, Min′ium.= _Syn._ TROCHISCI MINII (Ph. E. 1744), L. _Prep._ From red lead, 1 dr.; corrosive sublimate, 2 dr.; crumb of bread, 1 oz.; rose water, q. s.; to be made up into oat-like grains. For external use only.

=Lozenges, Morphia.= _Syn._ TROCHISCI MORPHIÆ (B. P., Ph. E.), T. M. HYDROCHLORATIS, L. _Prep._ 1. (Ph. E.) Hydrochlorate of morphia, 20 gr.; tincture of tolu, 1/2 fl. oz.; powdered white sugar, 25 oz.; dissolve the hydrochlorate in a little warm water, mix it with the tincture and the sugar, make a mass with mucilage of gum tragacanth, q. s., and divide it into 15-gr. lozenges. Each lozenge contains about 1/40 gr. of hydrochlorate of morphia. Used as opium lozenges, but are pleasanter. The morphia lozenges of the shop generally contain 1/24 gr. of hydrochlorate of morphia. (Pereira.)

2. (With IPECACUANHA, TROCHISCI MORPHIÆ ET IPECACUANHÆ——Ph. E.) As the last, adding of ipecacuanha, 1 dr. Each lozenge contains about 1/40 gr. of hydrochlorate of morphia, and 1/13 gr. of ipecacuanha. Anodyne and expectorant; in tickling coughs, &c., and to allay pain.

3. Hydrochlorate of morphia, 20 gr.; tincture of tolu, 1/2 oz.; refined sugar, in powder, 24 oz.; gum Arabic, in powder, 1 oz.; mucilage, 2 oz., or a sufficiency; boiling distilled water, 1/2 oz. Divide the mass into 720 lozenges. Each lozenge contains 1/36 gr. of hydrochlorate of morphia.——_Dose_, 1 or 2 occasionally, for cough.

=Lozenges, Morphia and Ipecacuanha.= _Syn._ TROCHISCI MORPHIÆ ET IPECACUANHÆ (B. P.) Hydrochlorate of morphia, 20 gr.; ipecacuanha, in fine powder, 24 oz.; tincture of tolu, 1/2 oz.; refined sugar, in powder, 24 oz.; gum Arabic, in powder, 1 oz.; mucilage, 2 oz., or a sufficiency; distilled water, 1/2 oz.; divide the mass into 720 lozenges. Each lozenge contains 1/36 gr. of hydrochlorate of morphia and 1/12 gr. of ipecacuanha.——_Dose_, 1 or 2 occasionally, for cough.

=Lozenges of Naphthalin.= (Dupasquier.) _Syn._ TROCHISCI NAPHTHALINI. _Prep._ Naphthalin, 5 scruples; sugar, 20 oz.; oil of aniseed to flavour; form a mass with mucilage of tragacanth, and divide into lozenges of 15 gr. each. Expectorant, and may be taken to the extent of 20 a day.

=Lozenges, Ni′tre.= _Syn._ TROCHISCI NITRICI, L. _Prep._ 1. (Ph. E. 1783.) Nitre, 3 oz.; white sugar, 9 oz.; mucilage of tragacanth, q. s. to mix. Diuretic; but chiefly sucked, without swallowing, to remove incipient sore throat.

2. Camphorated; TROCHISCI NITRI CAMPHORATI, L.——Chaussier. Each lozenge contains 1/8 gr. of opium, 1/2 gr. of camphor, and 1 gr. of nitre. In hoarseness, sore throat, &c.

=Lozenges, Nut′meg.= _Syn._ TROCHISCI MYRISTICÆ, L. From oil of nutmeg, 1 fl. dr., to each lb. of sugar, and coloured with infusion of saffron. Carminative and stomachic; in colic, &c.

=Lozenges, O′pium.= _Syn._ ANODYNE LOZENGES; TROCHISCI OPII (Ph. E.), T. GLYCYRRHIZÆ CUM OPIO, L. _Prep._ 1. (B. P., Ph. E.) Opium (strained), 2 dr.; tincture of tolu, 1/2 oz.; triturate together, add of powdered sugar, 6 oz.; extract of liquorice (soft) and powdered gum acacia, of each 5 oz.; mix, and divide into 10-gr. lozenges. Each lozenge contains 1/6 to 1/7 gr. of opium. Used to allay tickling cough and irritation of the fauces, and as an anodyne and hypnotic.

2. (Ph. U. S.) Opium (in fine powder), 2 dr.; extract of liquorice, gum Arabic, and sugar, of each 5 oz.; oil of aniseed, 1/2 fl. dr.; water, q. s.; divide into 6-gr. lozenges. Each lozenge contains 1/10 gr. of opium. As the last.

3. Extract of opium, 72 gr.; tincture of tolu, 1/2 oz.; refined sugar (in powder), 2 oz.; extract of liquorice, 6 oz.; distilled water, a sufficiency. Divide the mass into 720 lozenges. Each lozenge contains 1/10 gr. of extract of opium.——_Dose_, 1 to 2 lozenges.

=Lozenges, Or′ange.= _Syn._ TROCHISCI AURANTII, L. From oil of orange, 1-1/2 fl. dr. to each lb. of sugar, and infusion of saffron for colouring. By adding nitric or tartaric acid, 3 dr. ‘ACIDULATED ORANGE LOZENGES’ will be formed.

=Lozenges, Orange-flow′er.= _Syn._ TROCHISCI AURANTII FLORUM, L. _Prep._ (P. Cod.) Powdered sugar, 1 lb.; neroli, 1 dr.; orange-flower water, q. s.; make it into drops (pastilli); or, omit the water, and make it into lozenges with mucilage of tragacanth made with orange-flower water. Delightfully fragrant.

=Lozenges, Or′ris-root.= _Syn._ TROCHISCI IRIDIS, L. _Prep._ From orris-root (in very fine powder), 1 oz.; sugar, 1 lb.; mucilage of tragacanth, q. s. to mix. Used to perfume the breath.

=Lozenges Ox′alate of Potassa.= _Syn._ TROCHISCI POTASSÆ OXALATIS, T. P. SUPER-OXALATIS, L. As ACIDULATED LOZENGES, but using quadraoxalate of potassa (salt of sorrel) instead of tartaric acid. (See _below_.)

=Lozenges, Oxal′ic Acid.= _Syn._ TROCHISCI ACIDI OXALICI, L. As ACIDULATED LOZENGES, but using oxalic acid instead of tartaric acid. The last two are refrigerant, but their use is objectionable, especially for patients who labour under the oxalic diathesis. In large quantities they are poisonous.

=Lozenges, Paregor′ic.= _Syn._ TROCHISCI PAREGORICI, L. Medicated with 2 fl. oz. of paregoric and 2 dr. of tartaric acid, to each lb. of sugar, and tinged of a pink colour with lake or cochineal. As a pectoral in catarrhs, &c.

=Lozenges, Paullin′ia.= _Syn._ TROCHISCI PAULLINIÆ, T. GUARANÆ, L. _Prep._ (Dr Gavrelle.) Each lozenge contains nearly 1/2 gr. of extract of garana or paullinia, and is flavoured with vanilla. 12 to 20 daily, as an alterative and tonic; in chlorosis, diarrhœa.

=Lozenges, Pec′toral.= _Syn._ TROCHISCI PECTORALES, T. BECHICI, L. _Prep._ 1. (Dr Grunn.) Powdered squills, 4 parts; extract of lettuce, 8 parts; ipecacuanha, 18 parts; manna, 125 parts; sugar, 250 parts; mucilage of tragacanth, q. s. to mix.

2. (Magendie.) See LOZENGES, EMETINE.

3. (BLACK; T. BECHICI NIGRI.) See LOZENGES, LIQUORICE.

4. (WHITE; T. BECHICI ALBI.) Orris root, 4 dr.; liquorice powder, 6 dr.; starch, 1-1/2 oz.; sugar, 18 oz.; mucilage of tragacanth, q. s. to make a lozenge-mass.

5. (YELLOW; T. BECHICI FLAVI.) Powdered orris root, 6 dr.; starch, 4 dr.; liquorice powder, 3 dr.; saffron, 2 dr.; sugar, 8 oz.; mucilage of tragacanth, q. s. to mix.

_Obs._ All the above are used as demulcents in coughs, colds, &c. Nos. 1 and 2 are anodyne as well as demulcent. For other formulæ see LOZENGES, COUGH, LIQUORICE, OPIUM, &c.

=Lozenges, Pel′litory.= _Syn._ TROCHISCI PYRETHRI, L. _Prep._ From pellitory, mastic, and tragacanth, of each in fine powder, equal parts; orange-flower water, q. s. to mix. In toothache.

=Lozenges, Pep′permint.= _Syn._ TROCHISCI MENTHÆ PIPERITÆ, L. _Prep._ 1. (P. Cod.) Oil of peppermint, 1 dr.; powdered sugar, 16 oz.; mucilage of tragacanth, q. s.

2. (Ph. U. S.) Oil of peppermint, 1 fl. dr.; sugar, 12 oz.; mucilage of tragacanth, q. s.

3. (Wholesale.) 1 fl. dr. of the finest Mitcham oil of peppermint to each lb. of the finest double refined white sugar, with mucilage of either gum Arabic or tragacanth to mix.

_Obs._ The best peppermint lozenges are made of the very finest double refined sugar and of English oil of peppermint only; carefully mixed up with very clean mucilage. The commoner qualities are made by employing inferior lump sugar and foreign oil of peppermint, or, what is better, English oil of peppermint, but in a less proportion than for the better sorts. The addition of starch, in quantity varying from 1/6 to 2/9 of the whole mass, is also commonly made to them; and in the cheapest varieties even plaster of Paris or chalk is occasionally introduced by unprincipled makers. The addition of a very small quantity of blue smalts, reduced to an impalpable powder, is commonly made to the sugar, to increase its whiteness. ‘TRANSPARENT’ or ‘SEMI-TRANSPARENT PEPPERMINT LOZENGES’ are made from the same materials as the opaque ones; but the sugar is not reduced to quite so fine a powder, and the cake is rolled thinner before cutting it. A little oil of almonds or of olives is also occasionally mixed with the ingredients, to promote the transparency; but it tends to render the lozenges less white.

Peppermint lozenges and drops are useful in flatulency, nausea, and griping; and judging from the enormous and constantly increasing demand for them, they are more highly esteemed by the public than all other lozenges and confections.

=Lozenges, Pontefract.= These are made of the purest refined juice or extract of liquorice, and have long been esteemed as a demulcent.

=Lozenges, Pop′py.= _Syn._ TROCHISCI PAPAVERIS, L. _Prep._ From extract of poppies, 3 oz.; sugar, 15 oz.; powdered gum tragacanth, 2 oz.; rose water, q. s. to mix. Used in coughs as an anodyne and demulcent, in lieu of opium lozenges.

=Lozenges, Pulmon′ic.= See LOZENGES, COUGH, PECTORAL, WAFERS, &c.

=Lozenges, Quin′ine.= _Syn._ =Trochisci quininæ sulphatis=, L. _Prep._ (Soubeiran.) Each lozenge contains about 1/10 gr. of sulphate (disulphate) of quinine. Tonic and stomachic in dyspepsia, &c.; but to render them useful, the quantity of the alkaloid should be doubled.

=Lozenges, Reduced Iron.= _Syn._ TROCHISCI FERRI REDACTI. (B. P.) Reduced iron, 720 gr.; refined sugar, in powder, 25 oz.; gum Arabic, in powder, 1 oz.; mucilage, 2 oz.; distilled water, 1 oz., or a sufficiency. Mix the iron, sugar, and gum, and add the mucilage and water to form a proper mass. Divide into 720 lozenges, and dry them in a hot-air chamber with a moderate heat. Each lozenge contains 1 gr. of reduced iron.——_Dose_, 1 to 6 lozenges.

=Lozenges, Reduced Iron, with Chocolate.= (Bouchardat.) _Syn._ TROCHISCI CHOCOLATÆ ET FERRI. _Prep._ Fine chocolate, 14 oz.; iron reduced by hydrogen, 1 oz. Soften the chocolate by heat, mix with the iron, and divide into lozenges of 15-1/2 gr. each. Levigated iron filings are sometimes substituted for the reduced iron; others direct the peroxide.

=Lozenges of Rhatany.= (Th. Hosp.) _Syn._ TROCHISCI KRAMERIÆ. _Prep._ Extract of rhatany in powder, 1050 gr.; tragacanth, 70 gr.; sugar, 280 gr.; red currant paste, q. s. Mix, and divide into 350 lozenges, and finish as in benzoic acid lozenges.

=Lozenges, Rhu′barb.= _Syn._ DIGESTIVE LOZENGES; TROCHISCI RHEI, L. _Prep._ (P. Cod.) Powdered rhubarb, 1 oz.; sugar, 11 oz.; mucilage of tragacanth, q. s.; divide into 12-gr. lozenges. Stomachic and laxative. Sucked before dinner, they excite the appetite, and, after it, promote digestion. They are frequently aromatised with a little cinnamon or vanilla. See CANDY (Digestive).

=Lozenges, Rose.= _Syn._ TROCHISCI ROSÆ, L. _Prep._ 1. (ACIDULATED; T. R. ACIDÆ.) From otto, 5 to 10 drops; citric or tartaric acid, 3 dr.; sugar, 1 lb.; mucilage, q. s.

2. (Ph. E. 1746.) Red-rose leaves (powdered), 1 oz.; sugar, 12 oz.; mucilage, q. s.

3. (PÂTE DE ROSE LOZENGES.) As No. 1, omitting one half of the acid.

4. (RED; T. R. RUBRI.) As No. 1; but coloured with liquid lake, or infusion of cochineal.

_Obs._ Some makers add of starch, 4 oz., substitute oil of rhodium for otto of roses, and use mucilage made with rose water; but the quality of course suffers. They are chiefly used to perfume the breath.

=Lozenges, Saf′fron.= _Syn._ TROCHISCI CROCI, L. _Prep._ From hay saffron (in fine powder), 1 oz.; white sugar, 1 lb.; mucilage of gum tragacanth, q. s. to mix. Anodyne, pectoral, and emmenagogue; but chiefly used to raise the spirits in hypochondriasis.

=Lozenges, San′tonine.= _Syn._ TASTELESS WORM LOZENGES; TROCHISCI SANTONINI, L. Each lozenge contains 1/2 gr. (nearly) of santonine. 5 to 10 daily, as a vermifuge.

=Lozenges, Scammony.= (Bourières.) _Syn._ TROCHISCI SCAMMONII. _Prep._ Resin of scammony, 4 dr.; calomel, 4 dr.; sugar, 6 oz.; tragacanth, 1/2 dr.; tincture of vanilla, 40 minims. Make into 300 lozenges. 1 or 2 for a child; 2 to 4 for an adult.

=Lozenges, So′da.= _Syn._ TROCHISCI SODÆ BICARBONATIS (Ph. E.), L. _Prep._ 1. (Ph. E.) Bicarbonate of soda, 1 oz.; powdered gum Arabic, 1/2 oz.; sugar, 3 oz.; mucilage, q. s.

2. (Wholesale.) From bicarbonate of soda and powdered gum tragacanth, of each 2 oz.; double refined lump sugar, 3/4 lb.; rose water, q. s. to mix. In acidity, heartburn, &c. See LOZENGES, VICHY.

3. (With GINGER); TROCHISCI SODÆ ET ZINGIBERIS, L. To the last, add of ginger (in very fine powder), 1-1/2 oz.; powdered gum, 1/2 oz.

=Lozenges of Soluble Tartar.= (Guibort.) _Syn._ TROCHISCI TARTARI SOLUBILIS. _Prep._ Borotartrate of potash, 1 oz.; sugar, 7 oz.; mucilage of tragacanth, q. s.; flavoured with lemon.

=Lozenges, Squills.= _Syn._ TROCHISCI SCILLÆ, L. 1. Each lozenge contains 1/8 gr. of powdered squills and 2 gr. of extract of liquorice.

2. (With IPECACUANHA); TROCHISCI SCILLÆ ET IPECACUANHÆ, L. As the last, adding for each lozenge 1/4 gr. of powdered ipecacuanha. Both the above are useful cough lozenges.

=Lozenges, Starch.= _Syn._ TROCHISCI ALIMY, T. BECHICI ALBI. L. See PECTORAL LOZENGES.

=Lozenges, Steel.= _Syn._ TROCHISCI FERRI, T. CHALYBEATI, L. _Prep._ (P. Cod.) Levigated iron filings, 1 oz.; sugar, 10 oz.; cinnamon, 2 dr.; mucilage of tragacanth, q. s.; mix, and divide into 480 lozenges. Tonic. See LOZENGES, IRON.

=Lozenges, Sul′phur.= _Syn._ TROCHISCI SULPHURIS, L. _Prep._ (P. Cod.) From sulphur (pure precipitate), 2 oz.; sugar, 16 oz.; mucilage of tragacanth (made with rose water), q. s. to mix. Useful in piles and some skin diseases.

=Lozenges, Tannic Acid.= _Syn._ TROCHISCI ACIDI TANNICI (B. P.) Tannic acid, 360 gr.; tincture of tolu, 1/2 oz,; refined sugar, 25 oz.; gum acacia, 1 oz.; mucilage, 2 oz.; distilled water, 1 oz. Dissolve the tannic acid in the water; add first the tincture of tolu previously mixed with the mucilage, then the gum and the sugar, also previously well mixed. Form the whole into a proper mass, divide into 720 lozenges, and dry them in a hot-air chamber with a moderate heat. Each lozenge contains 1/2 gr. of tannic acid.——_Dose_, 1 to 6 lozenges.

=Lozenges, Tarta′ric Acid.= See LOZENGES, ACIDULATED.

=Lozenges, Tolu′.= _Syn._ BALSAMIC LOZENGES; TROCHISCI TOLUTANI, T. BALSAMICÆ, L. _Prep._ 1. (P. Cod.) Balsam of tolu and rectified spirit, of each 1 oz.; dissolve, add of water, 2 fl. oz., heat the mixture in a water bath, and filter; make a mucilage with the filtered liquid, and gum tragacanth (in powder), 80 gr.; add of sugar, 16 oz.; make a mass, and cut it into lozenges.

2. (Wholesale.) As the last, but using only one half the weight of balsam of tolu. Pectoral and balsamic.

=Lozenges, Tronchin’s.= _Syn._ TABLETTES DE TRONCHIN, Fr. See LOZENGES, COUGH.

=Lozenges, Vanil′la.= _Syn._ TROCHISCI VANILLÆ, L. _Prep._ 1. Essence of vanilla, 3 fl. dr., to each lb. of sugar.

2. (Guibourt.) From vanilla triturated to a fine powder with 7 times its weight of sugar. Antispasmodic, nervine, and stomachic. Used to sweeten the breath, to flavour chocolate, &c.

=Lozenges, Vichy.= _Syn._ D’ARCET’S LOZENGES; TROCHISCI SODÆ, L.; PASTILLES DE VICHY, Fr. _Prep._ 1. (P. Cod.) Bicarbonate of soda, 1 oz.; powdered sugar, 19 oz.; mucilage of gum tragacanth, q. s.; mix, and divide into 20-gr. lozenges.

2. (D’Arcet.) As the last, adding a little oil of peppermint to give a slight flavour. Antacid or absorbent; in heartburn, &c.

=Lozenges, Vi′olet.= _Syn._ TROCHISCI VIOLÆ, T. VIOLARUM, L. _Prep._ Orris lozenges coloured with the juice of violets.

=Lozenges, Wistar’s Cough.= _Prep._ Gum Arabic, extract of liquorice, and sugar, of each 2-1/2 oz.; powdered opium, 1 dr.; oil of aniseed, 40 drops; for 60 lozenges. One, three or four times a day.

=Lozenges Worm.= _Syn._ TROCHISCI ANTHELMINTICI, MORSULI CONTRA VERMES, L. Most of the advertised nostrums under this name have a basis of calomel (about 1 gr. per lozenge), and require to be followed by a purge a few hours afterwards.

1. (Ph. Austr. 1836.) Ethereal extract of wormseed, 1 dr.; jalap, starch, and sugar, of each 2 dr.; mucilage of gum tragacanth, q. s.; divide into 60 lozenges.

2. (Ph. Dan. 1840.) Wormseed, 1 oz.; ethiops mineral and jalap, of each 3 dr.; cinnamon, 2 dr.; sugar, 7 oz.; rose water, q. s. See LOZENGES, CALOMEL, CHING’S, SANTONIN, &c. (_above_).

=Lozenges, Zinc.= _Syn._ TROCHISCI ZINCI, T. Z. SULPHATIS, L. _Prep._ (Dr Copland.) Each lozenge contains 1/2 gr. of sulphate of zinc. Antispasmodic, expectorant, and tonic, and in quantity emetic.

=LUBRICATING COMPOUNDS.= See ANTI-ATTRITION.

=LU′CIFERS.= See MATCHES.

=LUMBA′GO.= Rheumatism of the loins. It is distinguished from nephritis, or inflammation of the kidneys, by the pain being aggravated on stooping. The treatment consists of strong stimulant embrocations or liniments, or of blisters over the parts affected, with active aperients, warmth, and diaphoretics (as Dover’s powder) at bedtime. The hot or vapour bath often gives almost immediate relief. See LINIMENT OF BELLADONNA and CHLOROFORM. See RHEUMATISM.

=LU′MINOUS PHIAL.= See PHOSPHORUS.

=LU′NA, CORNEA.= [L.] _Syn._ HORN SILVER. Fused chloride of silver.

=LU′NAR, CAUSTIC.= Fused nitrate of silver. See CAUSTIC and SILVER.

=LUNCHEONS, HOT, by the River Side.= We extract the following from ‘Land and Water’:——“In cold weather, by river side or on mountain or moor, when not too far from home, a hot lunch is often a _desideratum_, but one not easily accomplished without a more or less complicated apparatus and the trouble of lighting a fire——often an impossibility from the want of dry wood. A hot, substantial meal at the end of a hard day’s work is often difficult to get when the time of return home may depend entirely on the humour of the fish; and for either purpose nothing will beat the homely Hot Pot, or ‘Paté de Lancashire,’ as I have seen it pretentiously termed, though the latter name does not convey any of the comforting, cheering sensation to the inner man contained in the simpler denomination. I have never seen a good recipe for it, so append my own. Take a strong glazed earthenware jar of a cylindrical form, ten inches deep and twelve broad. At the bottom of this place a layer, about an inch thick, of potatoes cut into pieces, sprinkle with a little salt; on these place a layer of four or five mutton chops, season with salt and pepper, and a teaspoonful of Worcester sauce. Pour in enough broth, stock, or water to nearly cover the chops; then add another layer of potatoes (rather thicker than the first), on which place two or three chops, and two kidneys, cut into smallish pieces for the sake of the gravy. If mushrooms are procurable, add a few with each layer of meat, or, in place of these, a few oysters. Season, and continue the meat and potatoes in alternate layers until within an inch of the top, when cover with small potatoes whole, or large ones cut into halves or quarters; bake slowly in the oven till the potatoes are quite soft inside, and brown and well cooked at the top, when the dish is ready. If it is not wanted at once, it may easily be kept hot, and the addition of a little stock will prevent its getting dry. To serve out-of-doors, wrap up in cloths, and carry in a small hamper lined with straw, when it will keep steaming hot for an hour or more. One of the great excellences of this dish lies in the fact that all the aroma of the meat is retained, while the potatoes absorb any superfluous gravy. Sliced onions will improve the flavour for those who like them, especially when mushrooms cannot be got. I have tested the appreciation of this dish among a grouse-driving party on the Yorkshire moors on a raw December day, and there was no dissentient voice as to its merits when thankfully discussed over the subsequent pipe. I have found it not ungrateful, after a long day’s fishing, nearly up to my waist in water, when the dinner ordered for six, with a view of taking an evening basket, would have been ruined before my arrival at eleven, had it consisted of aught else; nay, I have assisted at more than one bachelor supper in chambers, where it formed the dish of the evening, and mid-day, evening, or night I have always found it good.”

=LUNGS.= In _anatomy_, the organ of respiration occupying the thorax or chest. See RESPIRATION.

=LU′PULIN.= _Syn._ LUPULINA, LUPULINE. Under this name two products are known, namely, 1. (LUPULINIC GRAINS, L. GLANDS.) The yellow powder obtained from the dried strobiles or catkins of the hops, by gently rubbing and sifting them.——_Dose_, 5 to 10 gr.; as an anodyne, tonic, &c.

2. The aromatic bitter principle of hops.

_Prep._ The aqueous extract of the yellow powder or lupulinic grains of the strobiles, along with a little lime, are treated with rectified spirit; the filtered tincture is evaporated to dryness, redissolved in water, and the solution is again filtered, and evaporated to dryness; the residuum is, lastly, washed with ether, and allowed to dry.

_Prop., &c._ The latter product is a yellowish-white, bitter, uncrystallisable substance, soluble in 20 parts of water, very soluble in alcohol, and slightly so in ether. The yellow powder above alluded to (No. 1) is improperly called lupulin; a name which appears more appropriate to the pure bitter principle than to the lupulinic grains.

_Adult._ The lupulin sold to brewers is largely adulterated with quassia. In some samples, lately examined, the quassia amounted to 70 per cent.

=LU′PUS.= In _pathology_, a disease affecting the skin, remarkable for eating away the parts which it attacks with extreme rapidity. It is generally confined to the face, and commences with small, spreading ulcerations, which become more or less concealed beneath bran-like scabs, and end in ragged ulcers, which gradually destroy the skin and muscular tissue to a considerable depth.

=LUS′TRE.= See PLUMBAGO.

=LUTE.= _Syn._ LUTING; LUTUM, CÆMENTUM, L. A composition employed to secure the joints of chemical vessels, or as a covering to protect them from the violence of the fire.

_Prep._ 1. Linseed meal, either alone or mixed with an equal weight of whiting, and made into a stiff paste with water. It soon becomes very hard and tough.

2. Ground almond cake, from which the oil has been pressed, mixed up as the last. Both the above are much used for stills, retorts, and other vessels that are not exposed to a heat higher than about 320° Fahr. They are capable of resisting the action of the fumes of volatile oils, spirits, weak acids, &c., for some time.

3. Fresh-slaked lime made into a paste with strained bullock’s blood or size. As the last.

4. Plaster of Paris made into a paste with water, and at once applied. It bears a nearly red heat, but becomes rather porous and friable.

5. Powdered clay or whiting made into putty with water and boiled linseed oil. This is commonly known as ‘fat lute.’

6. A mixture of powdered clay and ground bricks, made up with water or a solution of borax. For joining crucibles, &c., which are to be exposed to a strong heat.

7. Pipe-clay and horse-dung, made into a paste with water. As a coating for glass vessels, to preserve them from injury from exposure to the fire. This composition is used by the pipe-makers, and will stand unharmed the extremest heat of their kiln for 24 hours. It is applied by spreading it on paper.

8. As the last, but employing shredded tow or plumbago for horse-dung.

_Obs._ For the joints of small vessels, as tubes, &c., especially those of glass or earthenware, pieces of vulcanized Indian tubing, slipped over and tied above and below the joint, are very convenient substitutes for lutes, and have the advantage of lasting for a long time, and bearing uninjured the heat at which oil of vitriol boils. Flat rings or “washers” of vulcanised rubber are also excellent for still heads, &c., whenever the parts can be pinched together by screws or clamps.

=LYCOPO′DIUM.= The fine powder known in commerce under this name consists of the minute spores of the common club moss, or _Lycopodium clavatum_. It is exceedingly combustible; thrown suddenly from a powder-puff or bellows across the flame of a candle, it produces the imitation flashes of lightning of our theatres. The powder is also employed as a ‘dusting powder’ in excoriations, and to roll up boluses and pills.

According to M. Paul Cazeneuve, pine pollen is occasionally substituted for lycopodium.

=MACARO′NI.= This only differs from VERMICELLI in the size of the pipes, which are about as large as a goose-quill. When properly dressed it is very wholesome and nutritious. A pleasant dish may be made by boiling macaroni in water until soft, either with or without a little salt, draining off the water, and then stewing it with a little butter, cream, or milk, and grated cheese, adding spice to palate. It may be made into a ‘form’ and browned before the fire.

=MAC′AROONS (English).= _Prep._ Take of sweet almonds, 1 lb.; blanch and beat them to a paste, add of lump sugar 1-1/4 lb.; whites of 6 eggs; the grated yellow peel of 2 lemons; mix well, make it into ‘forms,’ cover with wafer paper, and bake in a moderate oven.

=MACE.= _Syn._ MACIS, L. The tough membranous, lacerated covering (ariliode) of the NUTMEG. It has a flavour and odour more agreeable than that of nutmeg, which in its general properties it resembles. It is used as a flavouring by cooks, confectioners, and liqueuristes; and in medicine as a carminative. See OIL, &c.

=MACERA′TION.= _Syn._ MACERATIO, L. The steeping of a substance in cold water, for the purpose of extracting the portion soluble in that menstruum. The word is also frequently applied to the infusion of organic substances in alcohol or ether, or in water, either alkalised or acidulated.

=MACKEREL.= The _Scomber Scombrus_ (Linn.), a well-known spiny-finned sea-fish, much esteemed at certain seasons for the table. Though nutritious, it is very apt to disagree with delicate stomachs, and occasionally induces symptoms resembling those of poisoning.

=MAD′DER.= _Syn._ RUBIA, RUBIÆ RADIX, L. The root of _Rubia tinctorum_ (Linn.), or dyer’s madder. The best madder has the size of a common goose-quill, a reddish appearance, and a strong odour. As soon as the roots are taken from the ground they are picked and dried; and before use they are ground in a mill. Levant, Turkey, and Smyrna madder is imported whole; French, Dutch, and Zealand madder, ground. The finest quality of ground madder is called ‘crop’ or ‘grappe,’ ‘ombro’ and ‘gamene’ are inferior sorts, and ‘mull’ the worst.

Madder contains several distinct principles as——madder red, or alizarin;——madder purple, or purpurin;——madder orange, or rubiacin; madder yellow, or xanthin, &c. The first of these (noticed _below_) is by far the most important.

_Pur._ Madder is frequently adulterated with logwood, Brazil wood, and other dye-stuffs of inferior value; and also, not unfrequently, with brickdust, red ochre clay, sand, mahogany sawdust, bran, &c. These admixtures may be detected as follows:——

1. When dried at 212° Fahr., and then incinerated, not more than 10% to 12% of ash should be left.

2. It should not lose more than 50% to 56% by exhaustion with cold water.

3. When assayed for alizarin (see _below_), the quantity of this substance obtained should be equal to that from a sample of the same kind of madder which is known to be pure, and which has been treated in precisely the same manner. The operation may be conducted as follows:——500 gr. of the sample are weighed, and, after being dried by the heat of boiling water or steam, are gradually added to an equal weight of concentrated sulphuric acid, contained in a glass vessel, and stirred with a glass rod; after a few hours the charred mass is washed with cold water, collected on a filter, and dried by the heat of boiling water; the carbonised mass (‘garacine’) is next powdered, and treated with successive portions of rectified spirit, to which a little ether has been added, at first in the cold, and afterwards with heat, until the liquid is no longer coloured by it, when the mixed tincture is filtered, and evaporated (distilled) to dryness; the weight of the residuum, divided by 5, gives the percentage of red colouring matter present. Or,——The dried carbonized matter is exhausted by boiling it in a solution of 1 part of alum in 5 or 6 parts of water, and the decoction, after being filtered whilst in the boiling state, is treated with sulphuric acid as long as a precipitate falls, which is washed, dried, and weighed as before.

_Uses, &c._ Madder has been given in jaundice and rickets, and as an emmenagogue.——_Dose_, 1/2 dr. to 2 dr., twice or thrice a day. It is principally employed as a dye-stuff. See RED DYES, IVORY, PURPURIN, &c., also _below_.

=MADDER RED.= _Syn._ ALIZARIN. C_{14}H_{8}O_{4}. 2Aq. The red colouring principle of madder, first obtained in a separate form by Robiquet.

_Prep._ 1. The aqueous decoction of madder is treated with dilute sulphuric acid as long as a precipitate falls, which, after being washed, is boiled in a solution of chloride of aluminum as long as it gives out colour; the liquid is then filtered, precipitated with hydrochloric acid, and the precipitate washed and dried. It may be purified from a little adhering purpurin, by dissolving it in alcohol, again throwing it down with hydrate of aluminum, boiling the precipitate with a strong solution of soda, and separating the alizarin from its combination with alumina by means of hydrochloric acid; it is lastly crystallised from alcohol.

2. (Meillet.) Alum, 3 parts, is dissolved in water at 140° Fahr., 30 parts, and madder, 13 parts, added to the solution; the whole is then gently boiled for 30 or 40 minutes, after which it is thrown upon a filter, and submitted to strong pressure; this treatment is repeated with fresh solutions a second and a third time; the mixed filtrates are then decanted, and when nearly cold, oil of vitriol, 1 part, diluted with twice its bulk of water, is added, care being taken to stir the liquid all the time; the supernatant fluid is next decanted, and the residuum well washed, and, lastly, dried in the air. If required quite pure, it is dissolved, whilst still moist, in a solution of 1-1/2 times its weight of carbonate of potassa in 15 parts of water, and, after reprecipitation with sulphuric acid, is washed and dried as before.

3. (Robiquet & Colin.) Powdered madder is exhausted with water of a temperature not exceeding 68° Fahr., and, after being dried, 1 part of it is boiled for 15 or 20 minutes in a solution of alum, 8 parts, in water, 40 parts; the liquid is filtered whilst boiling, the marc well washed with a fresh solution of alum, the mixed liquids precipitated with sulphuric acid, and the precipitate washed and dried, as before.

_Obs._ Alizarin has recently been produced artificially by Graebe and Liebermann from anthracene (C_{14}H_{10}), a liquid hydrocarbon existing in coal-tar. For a description of the process see ALIZARIN, ARTIFICIAL.

4. Madder exhausted by 2 or 3 macerations in 5 or 6 times its weight of cold water, is submitted to strong pressure, to remove adhering water, and the marc, whilst still moist, is mixed with half its weight of oil of vitriol diluted with an equal quantity of water; the whole is kept at the temperature of 212° for an hour, and after being mixed with cold water is thrown on a linen strainer, well washed with cold water, and dried.

5. From powdered madder and oil of vitriol, equal parts, without heat, as described under MADDER.

6. (F. Steiner.) The ‘used madder’ of the dye-works is run into filters, and precipitated with sulphuric acid; the matter thus obtained is put into bags and rendered as dry as possible by hydraulic pressure; the pressed cake is next crumbled to pieces, placed in a leaden vessel, and treated with 1-5th of its weight of oil of vitriol, afterwards assisting the action of the acid by introducing steam to the mixture; the resulting dark brown carbonized mass is, lastly, well washed, dried, powdered, and mixed with about 5% of carbonate of soda, when it is ready for sale.

_Obs._ The last three formulæ produce the ‘GARANCE’ or ‘GARANCINE’ of commerce, now so extensively used in dyeing.

_Prop., &c._ Pure anhydrous alizarin crystallises in magnificent orange-red crystals, which may be fused and sublimed; it is freely soluble in alkaline solutions, which it colours purple or violet; and, in oil of vitriol, giving a rich red colour; water throws it down from the last unchanged; it is also soluble in hot alcohol, a hot solution of alum, and, less freely, in hot water. Hydrated alizarin occurs in small scales resembling mosaic gold. When impure, it generally forms shining reddish-brown scales. Commercial ‘garancine’ is a deep-brown or puce-coloured powder, and will probably, ere long, entirely supersede crude madder for dyeing. The properties of garancine as a dye-stuff are precisely similar to those of madder. A solution of alum added to a solution of alizarin, and precipitated by carbonate of potassa, furnishes a rose lake; which, after being washed with water and dried, possesses a most charming tint.

=MAGILP′.= _Syn._ MEGELLUP. A mixture of pale linseed oil and mastic varnish, employed by artists as a ‘vehicle’ for their colours. The proportions vary according to the work. It is thinned with turpentine.

=MAG′ISTERY.= _Syn._ MAGISTERIUM, L. The old name of precipitates. The following are the principal substances to which this term has been applied:——MAGISTERY OF ALUM, hydrate of alumina; M. OF BISMUTH, sub-nitrate of bismuth; M. OF DIAPHORETIC ANTIMONY, washed diaphoretic antimony; M. OF OPIUM (Ludolph’s), crude morphia; M. OF LAPIS CALAMINARIS or M. OF ZINC, hydrated oxide of zinc.

=MAGNESIA.= See MAGNESIUM, OXIDE OF.

=Magnesia, Hydrate of.= (P. Cod.) _Syn._ MAGNESIÆ HYDRAS. Obtained by boiling magnesia in 20 or 30 times its weight of water for 20 minutes, draining on a linen cloth and drying. It contains 31 per cent. of water.

=Magnesia, Lactate of= (Ph. Ger.) _Syn._ MAGNESIÆ LACTAS. _Prep._ Mix 1 oz. (by weight) of lactic acid in 10 oz. of distilled water, just made slightly warm, and add light carbonate of magnesia enough to neutralise it. Filter and evaporate till crystals form.

=MAGNE′SIAN APE′′RIENT (Effervescing).= _Prep._ 1. Heavy carbonate of magnesia, 2 lbs.; tartaric acid and double refined lump sugar, of each 1-1/2 lb.; bicarbonate of soda (dried without heat), 1 lb.; each separately dried and in very fine powder; essential oils of orange and lemon, of each 1/2 fl. dr.; mix well in a warm, dry situation, pass the whole through a sieve, put it into warm, dry bottles, and keep them well corked.

2. As the last, but substituting calcined magnesia, 1 lb., for the heavy carbonate, and adding sugar, 3/4 lb. The preceding furnish a very pleasant effervescing saline draught.

3. (MOXON’S.)——_a._ Take of sulphate of magnesia, 2 lbs.; dry it by a gradually increased heat, powder, add of tartaric acid (also dried and powdered), 1-1/4 lb.; calcined magnesia, 1/2 lb.; finely powdered white sugar, 3 lbs.; bicarbonate of soda (dried without heat), 1 lb.; essence of lemon, 1 dr.; mix, and proceed as before.

_b._ (Durande.) Carbonate of magnesia, 1 part; bicarbonate of soda, tartrate of soda and potassa (sel de Seignette), and tartaric acid, of each 2 parts; mix as before.

_c._ (Pharm. Journ.) Sulphate of magnesia and bicarbonate of soda, of each 1 lb.; tartaric acid, 1/2 lb.; mix as before. The last two are much less agreeable than the others.

4. Carbonate of magnesia, 2 parts; calcined magnesia, 4 parts; citric acid, 13 parts; lump sugar, 25 parts; essence of lemon, q. s. to flavour. Very agreeable. This is known as ‘ROGÉS PURGATIF,’

_Obs._ The above are very useful and popular medicines in indigestion, heartburn, nausea, habitual costiveness, dyspepsia, &c.——_Dose_, 1/2 to 2 dessert-spoonfuls, thrown into tumbler 3 parts filled with cold water, rapidly stirred and drank whilst effervescing, early in the morning fasting, or between breakfast and dinner.

=MAGNESIAN LEMONADE′.= See CITRATE OF MAGNESIA and LEMONADE (Aperient).

=MAGNESIUM.= Mg. _Syn._ MAGNIUM, TALCIUM. The metallic radical of magnesia. The existence of this metal was demonstrated by Sir H. Davy in 1808; but it was first obtained in sufficient quantity to examine its properties by Bussy in 1830.

_Prep._ 5 or 6 pieces of sodium, about the size of peas, are introduced into a test-tube, and covered with small fragments of chloride of magnesium; the latter is then heated to near its point of fusion, when the flame of the lamp is applied to the sodium, so that its vapour may pass through the stratum of heated chloride; when the vivid incandescence that follows is over, and the whole has become cold, the mass is thrown into water, and the insoluble metallic portion collected and dried.

Commercial magnesium is prepared by evaporating solution of the chlorides of sodium and magnesium, in the proportion of 1 to 3, to dryness, mixing with one quarter of its weight of fluor spar and a like amount of sodium, and heating to bright redness in an iron crucible of proper construction.

On a larger scale it is prepared by heating to redness a mixture of chloride of magnesium, 9 parts; fused chloride of sodium, 1-1/2 parts; fluoride of calcium, 1-1/2 parts; and sodium in slices, 1-1/2 parts.

_Prop., &c._ In colour and lustre it resembles silver, but in chemical properties is more like zinc; its sp. gr. is only 1·743; it is malleable; fusible at a red heat, and can be distilled like zinc; unaffected by dry air and by cold water; burns with brilliancy when heated to dull redness in air or oxygen gas, yielding oxide of magnesium; inflames spontaneously in chlorine, yielding chloride of magnesium; it dissolves in the acids with the evolution of hydrogen gas, and pure salts of magnesium result.

It has been used somewhat extensively as an illuminating agent for photographing at night, and also for the purpose of affording a brilliant light for microscopic and magic lantern effects.

=Magnesium, Bromide.= _Syn._ MAGNESII BROMIDUM. To bromide of iron in solution add calcined magnesia in excess, heat the mixture, filter, and evaporate the clear solution to dryness.

=Magnesium, Carbonate of (Light).= _Syn._ LIGHT CARBONATE OF MAGNESIA; CARBONATE OF MAGNESIA; MAGNESIA; MAGNESIÆ CARBONAS LEVIS (B. P.). 3MgCO_{3}.MgO.5H_{2}O. _Prep._ 1. (Ph. L.) Sulphate of magnesium, 4 lbs., and carbonate of sodium, 4 lbs. 9 oz.; boiling distilled water, 4 galls.; dissolve the salts separately in one half the water, filter, mix the solutions, and boil for 2 hours, constantly stirring with a spatula, distilled water being frequently added to compensate for that lost by evaporation; lastly, the solution being poured off, wash the precipitated powder with boiling distilled water, and dry it. The formulæ of the Ph. E. & D. are essentially the same, except that the ebullition is limited to from 10 to 20 minutes.

2. (B. P.) Similar to the foregoing except that precipitation takes place in the cold. The formula of this compound is (Mg.CO_{3})_{3}. Mg(HO)_{2}.4(H_{2}O).

3. (HENRY’S.) Ordinary carbonate of magnesia, the washing of which has been finished with a little rose water.

4. Add a solution of carbonate of potassium or sodium to the bittern or residuary liquor of the sea-salt works, and well wash and dry the precipitate as before. This is known in commerce as ‘Scotch magnesia.’

_Obs._ The carbonate of magnesia of commerce is usually made up into cakes or dice while drying; or it is permitted to drain and dry in masses, which are then cut into squares with a thin knife. It is powdered by simply rubbing it through a wire sieve. The presence of iron in the solution of the sulphate of magnesium, when the crude salt is employed, and which is destructive to the beauty of the preparation may be got rid of by the addition of lime water until the liquor acquires a slight alkaline reaction, and subsequent decantation after repose.

=Magnesium, Carbonate of (Heavy).= _Syn._ HEAVY CARBONATE OF MAGNESIA; MAGNESIÆ CARBONAS (B. P.). 3MgCO_{3}.MgO.5H_{2}O. _Prep._ 1. Apothecaries’ Hall. A saturated solution of sulphate of magnesium, 1 part, is diluted with water, 3 parts, and the mixture heated to the boiling point; a cold saturated solution of carbonate of sodium, 1 part (all by measure), is then added, and the whole is boiled with constant agitation until effervescence ceases; boiling water is next freely poured in, and after assiduous stirring for a few minutes, and repose, the clear liquid is decanted, and the precipitate thrown on a linen cloth and thoroughly washed with hot water; it is, lastly, drained, and dried in an iron pot.

2. (Ph. D.) Dissolve sulphate of magnesium, 10 oz., in boiling distilled water, 1/2 pint; and carbonate of sodium (cryst.), 12 oz., in boiling distilled water, 1 pint; mix the two solutions, and evaporate the whole to dryness by the heat of a sand bath; then add of boiling water 1 quart, digest with agitation for half an hour, and wash the insoluble residuum as before; lastly, drain it, and dry it at the temperature of boiling water.

3. (B. P.) White granular powder precipitated from a boiling solution of sulphate of magnesium by a solution of carbonate of sodium, the whole evaporated to dryness, and the dry residue digested in water, collected on a filter, and washed.

_Prop._ The ordinary or light carbonate of magnesia is a white, inodorous, tasteless powder, possessing similar properties to calcined magnesia, except effervescing with acids, and having less saturating power. An ounce measure is filled by 45 to 48 gr. of the powder lightly placed in it. The heavy carbonate is sometimes fully thrice as dense (see _below_), but in other respects is similar.

_Dose._ As an antacid, 1/2 to a whole teaspoonful, 3 or 4 times daily; as a laxative 1/2 dr. to 2 dr. It is commonly taken in milk. It is apt to produce flatulence, but in other respects is preferable to calcined magnesia.

_General Remarks._ Although commonly called ‘carbonate of magnesia,’ the above substance, whether in the light or heavy form, appears to be a compound of carbonate with hydrate, in proportions which are not perfectly constant. (For B. P. formula see preceding article.) On account of the excess of base in its composition it was formerly regarded as a subsalt (subcarbonate of magnesia). A great deal has been written uselessly respecting the preparation of these carbonates, about which, however, there is neither mystery nor difficulty, as some writers would lead their readers to suppose. If the solutions are very dilute, the precipitate is exceedingly light and bulky; if otherwise, it is denser. By employing nearly saturated solutions, and then heating them and mixing them together whilst very hot, a very heavy precipitate is obtained, but it is apt to be gritty or crystalline. The same occurs when cold solutions are mixed, and no heat is employed. The lightest precipitate is obtained from cold, highly dilute solutions, and subsequent ebullition of the mixture.

Mr Pattinson, a chemist of Gateshead, prepares a very beautiful and pure heavy carbonate from magnesian limestone. The latter is calcined at a dull red heat (not hotter) for some time, by which the carbonic anhydride is expelled from the carbonate of magnesium, but not from the carbonate of calcium, which hence continues insoluble. The calcined mass is next reduced to a milk with water in a suitable cistern, and the carbonic anhydride resulting from its own calcination forced into it under powerful pressure. The result is a saturated solution of carbonate of magnesia, the lime remaining unacted on so long as the magnesium is in excess. The solution by evaporation yields the heavy carbonate, whilst carbonic anhydride is expelled, and may be again used in the same manufacture. 154 to 160 gr. of the heavy carbonate are required to fill an ounce measure when lightly placed in it, by which it appears to be fully thrice as dense as the light carbonate. The bicarbonate of magnesium (magnesiæ bicarbonas, L.) exists only in solution. The so-called ‘fluid magnesias’ of Murray, Dinneford, Husband, &c., are solutions of this salt. The small prismatic crystals which are deposited when ‘fluid magnesia’ is exposed to the air for some time consist of hydrated neutral carbonate, and not bicarbonate, as is sometimes stated.

=Magnesium, Chloride of.= MgCl_{2}. _Syn._ MAGNESII CHLORIDUM, L. _Prep._ (Liebig.) By dissolving magnesia in hydrochloric acid, evaporating to dryness, adding an equal weight of chloride of ammonium, projecting the mixture into a red-hot platinum crucible, and continuing the heat till a state of tranquil fusion is attained. On cooling, it forms a transparent, colourless, and very deliquescent mass, which is anhydrous, and soluble in alcohol.

_Obs._ Without the addition of the chloride of ammonium it is impossible to expel the last portion of the water without at the same time driving off the chlorine, in which case nothing but magnesia is left. The fused mass should be poured out on a clean stone, and when solid broken into pieces, and at once transferred to a warm, dry bottle. The P. Cod. orders the solution to be evaporated to the sp. gr. 1·384, and to be put, whilst still hot, into a wide-mouthed flask to crystallise.——_Dose_, 1 to 4 dr.; as a laxative.

=Magnesium, Cit′rate of.= Mg_{3}(C_{6}H_{5}O_{7})_{2}. _Syn._ MAGNESIÆ CITRAS. L. _Prep._ There is some difficulty in obtaining this salt in an eligible form for medicinal purposes. When precipitated from a solution it is insoluble. The following formulæ can be highly recommended.

1. (Parrish.) Dissolve crystallised citric acid, 100 gr., in water, 15 drops, and its own ‘water of crystallisation’ by the aid of heat; then stir in calcined magnesia, 35 gr.; a pasty mass will result, which soon hardens, and may be powdered for use.

_Obs._ The chief practical difficulty in this process results from the great comparative bulk of the magnesia, and the very small quantity of the fused mass with which it is to be incorporated. A part of the magnesia is almost unavoidably left uncombined, and the salt is consequently not neutral. The uncombined earth should be dusted off the mass before powdering the latter. A high temperature must be avoided.

2. (Robiquet.) Citric acid, 35-1/4 parts, is powdered and dissolved in boiling water, 10-5/8 parts; when the solution is cold, and before it crystallises, it is poured in a wide earthen vessel, kept cold by surrounding it with water; then, by means of a sieve, carbonate of magnesium, 21-1/6 parts, is distributed evenly and rapidly over the surface without stirring; when the reaction ceases the mixture is beaten rapidly as long as it retains its pasty consistence. The salt should be dried at a temperature not exceeding 70° Fahr.

3. (Effervescing; MAGNESIÆ CITRAS EFFERVESCENS, L.)——_a._ Citric acid (dried and powdered), 7 parts; heavy carbonate of magnesium, 5 parts; mix, and preserve in well-corked bottles.

_b._ (Ellis.) Mix powdered citric acid, 2-1/2 oz., with powdered sugar, 8 oz.; triturate to a fine powder, and drive off the water of crystallisation by the heat of a water bath; add citrate of magnesium (prepared by fusion), 4 oz., and oil of lemons, 10 drops, and mix intimately; then add bicarbonate of sodium, 3 oz., and again triturate until the whole forms a fine powder, which must be preserved in stoppered bottles. From 1 to 3 tablespoonfuls, mixed in a tumbler of water, furnishes an effervescing draught in which the undissolved portion is so nicely suspended, that it can be taken without inconvenience.

_c._ (Ph. Germ.) Light carbonate of magnesia, 25 oz.; citric acid, 75 oz.; distilled water, q. s.; mix into a thick paste and dry at 86° Fahr. With 14 oz. of the dried mass mix bicarbonate of soda, 13 oz.; citric acid, 6 oz.; sugar, 3 oz. Sprinkle over the mixture enough rectified spirit so as to make it sufficiently moist to be granulated by rubbing through a tinned iron sieve.

_d._ (Extemporaneous.) Citric acid (cryst.), 20 gr.; carbonate of magnesium, 14 gr.; mix in a tumbler of cold water, and drink the mixture whilst effervescing. A pleasant saline.

_Obs._ A dry white powder, sometimes sold as citrate of magnesia in the shops, is quite a different preparation to the above, and does not contain a particle of citric acid. The following formula is that of a wholesale London drug-house that does largely in this article:——

Calcined magnesia, magnesium oxide, 1-1/4 lb. (or carbonate, 2 lbs.); powdered tartaric acid, 1-1/2 lb.; bicarbonate of sodium, 1 lb.; dry each article by a gentle heat, then mix them, pass the mixture through a fine sieve in a warm dry room, and keep it in well-corked bottles. A few drops of essence of lemon and 3 lbs. of finely powdered sugar are commonly added to the above quantity. This addition renders it more agreeable.

_Prop., &c._ Citrate of magnesium is a mild and agreeable laxative; its secondary effects resemble those of the carbonate.——_Dose._ As a purgative, 1/2 to 1 oz. The dose of the effervescing citrate must depend on the quantity of magnesia present. A solution of this salt in water, sweetened and flavoured with lemon, forms magnesian lemonade.

=Magnesium, Boro-cit′rate of.= _Syn._ MAGNESIÆ BORO-CITRAS, L. _Prep._ (Cadet.) Boracic acid (in powder), 113 gr.; oxide of magnesium, 80 gr.; mix in a porcelain capsule, and add enough of a solution of citric acid, 260 gr., in water, 3-1/2 pints, to form a thin paste; then add the remainder of the citric solution, and gently evaporate, with constant stirring, to dryness. A cooling saline, and, in small doses, emmenagogue and lithontriptic.——_Dose._ As an aperient, 3 to 6 dr.

=Magnesium, Oxide of.= MgO. _Syn._ OXIDE OF MAGNESIUM, CALCINED MAGNESIA, MAGNESIA (B. P., Ph. L.).

_Prep._ 1. (B. P.) Magnesium carbonate, heated in a crucible until all the carbonic anhydride is driven off.

_Prop., &c._ White heavy powder, scarcely soluble in water, but readily soluble in acids without effervescence. Its solution in hydrochloric acid, neutralised by a mixed solution of ammonia and ammonium chloride, gives a copious crystalline precipitate when sodium phosphate is added to it. See next preparation.

=Magnesia levis= (B. P.) _Syn._ LIGHT MAGNESIA. _Prep._ (B. P.) 1. Light carbonate of magnesium heated in a Cornish crucible until all the carbonic anhydride is driven off.

A bulky white powder, differing from the magnesia (B. P.) only in its density, the volume occupied by the same weight being 3-1/2 to 1.

The properties of the two varieties of magnesium oxide are identical, and are used in medicine as antacids, laxatives, and antilithics, and much used in dyspepsia, heartburn, &c.——_Dose_, 10 to 20 gr. as an antacid and 20 to 60 gr. as a purgative.

=Magnesium, Phos′phate of.= MgHPO_{4}.6Aq. _Syn._ MAGNESIÆ PHOSPHAS, L. _Prep._ From the mixed solutions of phosphate of sodium and sulphate of magnesium, allowed to stand for some time. Small, colourless, prismatic crystals, which, according to Graham, are soluble in about 1000 parts of cold water. Phosphate of magnesium exists in the grains of the cereals, and in considerable quantity in beer. It is also found in guano.

=Magnesium and Ammo′′nium, Phosphate of.= MgNH_{4}.PO_{4}, 6 Aq. _Syn._ AMMONIO-PHOSPHATE OF MAGNESIA; MAGNESIÆ ET AMMONIÆ PHOSPHAS, L. This compound falls as a white crystalline precipitate whenever ammonia or carbonate of ammonium is added, in excess, to a solution of a salt of magnesium which has been previously mixed with a soluble phosphate, as that of soda. It subsides immediately from concentrated solutions, but only after some time from very dilute ones.

_Prop., &c._ Ammonio-phosphate of magnesium is very slightly soluble in pure water; when heated, it is resolved into pyrophosphate of magnesium, and is vitrified at a strong red heat. It is found in wheaten bran, guano, potatoes, &c., and occasionally forms one of the varieties of urinary calculi.

=Magnesium, Sil′icates of.= There are several native silicates of magnesia, more or less pure, of which, however, none is directly employed in medicine. Meerschaum and steatite or soapstone are well-known varieties. Serpentine is a compound of silicate and hydrate of magnesium. The minerals augite and hornblende are double salts of silicic acid, magnesium, and calcium with some ferrous oxide. The beautiful crystallised mineral called chrysolite is a silicate of magnesium, coloured with ferrous oxide. Jade is a double silicate of magnesium and aluminum, coloured with chromic oxide.

=Magnesium, Sulphate of.= MgSO_{4}, 7 Aq. _Syn._ EPSOM SALT, MAGNESIÆ SULPHAS (B. P. Ph. L. E. & D.), SAL EPSOMENSIS, L. This compound was originally extracted from the saline springs of Epsom, Surrey, by Dr Grew, in 1695. It is now exclusively prepared on the large scale, and from either magnesian limestone or the residual liquor of the sea-salt works.

_Prep._ 1. From dolomite or magnesian limestone.——_a._ The mineral, broken into fragments, is heated with a sufficient quantity of dilute sulphuric acid to convert its carbonates into sulphates; the sulphate of magnesium is washed out of the mass with hot water, and the solution, after defecation, is evaporated and crystallised.

_b._ The ‘limestone,’ either simply broken into fragments or else calcined (burnt), and its constituents quicklime and oxide magnesium converted into hydrates by sprinkling (slaking) it with water, is treated with a sufficient quantity of dilute hydrochloric acid to dissolve out all the calcium hydrate without touching the magnesium hydrate; the residuum of the latter, after being washed and drained, is dissolved in dilute sulphuric acid, and crystallised as before.

2. From bittern.——_a._ The residual liquor or mother-water of sea-salt is boiled for some hours in the pans which are used during the summer for the concentration of brine; the saline solution is then skimmed and decanted from some common salt which has been deposited, after which it is concentrated by evaporation, and, finally, run into wooden coolers; in about 36 hours, 1-8th part of Epsom salts usually crystallises out. This is called ‘singles.’ By re-dissolving this in water, and re-crystallisation, ‘doubles,’ or Epsom salts fit for the market, are obtained. A second crop of crystals may be procured by adding sulphuric acid to the mother-liquor, and re-concentrating the solution, but this is seldom had recourse to in England. Bittern yields fully 5 parts of sulphate of magnesia for every 100 parts of common salt that has been previously obtained from it.

_b._ A concentrated solution of sulphate of sodium is added to bittern, in equivalent proportion to that of the chloride of magnesium in it, and the mixed solution is evaporated at the temperature of 122° Fahr. (Ure); cubical crystals of common salt are deposited as the evaporation proceeds, after which, by further concentration and repose, regular crystals of sulphate of magnesia are obtained.

_c._ A sufficient quantity of calcined and slaked magnesian limestone is boiled in bittern to decompose the magnesium salts, and the liquid is evaporated, &c., as before. This is a very economical process.

_Prop._ Small acicular crystals, or (by careful crystallisation) large four-sided rhombic prisms; colourless; odourless, transparent; slightly efflorescent; extremely bitter and nauseous; when heated, it fuses in its water of crystallisation, the larger portion of which readily passes off, but one equivalent of water is energetically retained; at a high temperature it runs into a species of white enamel; it dissolves in its own weight of cold water, and in 3-4ths of that quantity of boiling water; it is insoluble in both alcohol and ether. Sp. gr. 1·66.

_Pur._ Sulphate of magnesium is soluble in an equal weight of water at 60° Fahr., by which it may be distinguished from sulphate of sodium, which is much more soluble.

An aqueous solution in the cold is not precipitated by oxalate of ammonium. The precipitate given by carbonate of sodium from a solution of 100 gr. should, after well washing and heating to redness, weigh 16·26 gr. (B. P.)

Digested in alcohol, the filtered liquid does not yield a precipitate with nitrate of silver nor burn with a yellow flame, and evaporates without residue. “Not deliquescent in the air.” (Ph. L.) 100 gr. of the pure crystallised sulphate yields 16-1/4 gr. of calcined magnesium oxide. (Pereira.) 10 gr., dissolved in 1 fl. oz. of water, and treated with a solution of carbonate of ammonium, are not entirely precipitated by 280 minims of solution of phosphate of sodium. (Ph. E.)

_Uses, &c._ Sulphate of magnesium is an excellent cooling purgative, and sometimes proves diuretic and diaphoretic.——_Dose_, 1 dr. to 1 oz., as a purgative, or an antidote in poisoning by lead. Large doses should be avoided. Instances are on record of their having proved fatal. Dr Christison mentions the case of a boy 10 years old who swallowed 2 oz. of salts, and died within 10 minutes. The best antidote is an emetic. A small quantity of Epsom salts, largely diluted with water (as a drachm to 1/2 pint or 3/4 pint), will usually purge as much as the common dose. This increase of power has been shown by Liebig to result rather from the quantity of water than the salt. Pure water is greedily taken up by the absorbents; but water holding in solution saline matter is rejected by those vessels, and consequently passes off by the intestines.

_Obs._ Oxalic acid has occasionally been mistaken for Epsom salt, with fatal results. They may be readily distinguished from each other by the following characteristics:——

EPSOM SALT. | OXALIC ACID. Tastes extremely bitter | Tastes extremely sour. and nauseous. | | Volatilises when heated Does not volatilise | on platinum foil. when heated on platinum | foil. Does not | Produces milkiness produce milkiness | when dissolved in when dissolved in | _hard_ water. _hard_ water. |

=Magnesium, Tar′trate of.= _Syn._ MAGNESIÆ TARTRAS, MAGNESIA TARTARICA, L. _Prep._ By saturating a solution of tartaric acid with carbonate of magnesium, and gently evaporating to dryness. It is only very slightly soluble in water.——_Dose_, 20 to 60 gr., or more; in painful chronic maladies of the spleen. (Pereira, ex Radmacher.) The effervescing tartrate of magnesium, commonly sold under the name citrate, has already been noticed.

=Magnesium and Potas′sium, Tartrate of.= _Syn._ POTASSIO-TARTRATE OF MAGNESIA; MAGNESIÆ POTASSIO-TARTRAS, M. ET POTASSÆ TARTRAS, L. _Prep._ From acid tartrate of potassium (in powder), 7 parts; carbonate of magnesium, 2 parts; water, 165 parts; boiled until the solution is complete, and then evaporated and crystallised. A mild aperient.——_Dose_, 1 to 5 dr.; in scurvy, &c.

=MAG′NET.= _Syn._ MAGNES, L. Besides its application to the loadstone, this name was formerly given to several compounds used in medicine.——ARSENICAL MAGNET (MAGNES ARSENICALIS), a substance once used as a caustic, consisted of common antimony, sulphur, and arsenious acid, fused together until they formed a sort of glass. MAGNES EPILEPSIÆ was native cinnabar.

=MAHOG′ANY.= This is the wood of _Swietenia Mahogoni_ (Linn.), a native of the hotter parts of the new world. It is chiefly imported from Honduras and Cuba. The extract is astringent, and has been used in tanning, and as a substitute for cinchona bark. The wood is chiefly employed for furniture and ornamental purposes, and, occasionally, in ship-building.

Imitations of mahogany are made by staining the surface of the inferior woods by one or other of the following methods:

1. Warm the wood by the fire, then wash it over with aquafortis, let it stand 24 hours to dry, and polish it with linseed oil reddened by digesting alkanet root in it; or, instead of the latter, give the wood a coat of varnish, or French polish which has been tinged of a mahogany colour with a little aloes and annotta.

2. Socotrine aloes, 1 oz.; dragon’s blood, 1/2 oz.; rectified spirit, 1 pint; dissolve, and apply 2 or 3 coats to the surface of the wood, previously well smoothed and polished; lastly, finish it off with wax or oil tinged with alkanet root.

3. Logwood, 2 oz.; madder, 8 oz.; fustic, 1 oz.; water, 1 gall.; boil 2 hours, and apply it several times to the wood boiling hot; when dry, slightly brush it over with a solution of pearlash, 1 oz.; in water, 1 quart; dry, and polish as before.

4. As the last, but using a decoction of logwood, 1 lb., in water, 5 pints. The tint may be brightened by adding a little vinegar or oxalic acid, and darkened by a few grains of copperas.

Stains and spots may be taken out of mahogany furniture with a little aquafortis or oxalic acid and water, by rubbing the part with the liquid by means of a cork till the colour is restored; observing afterwards to well wash the wood with water, and to dry it and polish it as before.

=MAIZE.= _Syn._ INDIAN CORN. The seeds of _Zea Mays_ (Linn.). Like the other corn plants, it belongs to the Grass family (_Graminaceæ_), and has albuminous grains sufficiently large and farinaceous to be ground into flour.

Maize is extremely nutritious, and although it is poorer in albumenoid matters than wheat, it is, of all the cereal grains, the richest in fatty oil, of which it contains about 9%. (Dumas and Payen.) It is remarkable for its fattening quality on animals, but is apt to excite slight diarrhœa in those unaccustomed to its use. Its meal is the ‘POLENTA’ of the shops. The peculiar starch prepared from it is known as ‘CORN FLOUR,’ In America the young ears are roasted and boiled for food.

The centesimal composition of maize is as follows:——Flesh formers (albumenoid bodies), 9·9; heat and fat formers (starch, dextrin, and fat), 71·2, fibre, 4·0; ash, 1·4; water, 13·5.

Letheby says of maize: “The grain is said to cause disease when eaten for a long time, and without other meal——the symptoms being a scaly eruption upon the hands, great prostration of the vital powers, and death after a year or so, with extreme emaciation.

These effects have been frequently observed amongst the peasants of Italy, who use the meal as their chief food, but I am not aware of any such effects having been seen in Ireland, where it is often the only article of diet for months together.”

Millions of bushels are grown every year in the United States of America, and large quantities are continually imported into England, where it is held in high esteem by cattle breeders, it being much cheaper than many of our home-grown productions. It is occasionally given to horses as a substitute for oats.

=MALAG′MA.= In _pharmacy_, a poultice or emollient application.

=MA′LIC ACID.= H_{3}C_{4}H_{3}O_{5}. _Syn._ ACIDUM MALICUM, L. This acid exists in the juice of many fruits and plants, either alone or associated with other acids, or with potassa or lime. In the juice of the garden rhubarb it exists in great abundance, being associated with acid oxalate of potassa.

_Prep._ (Everitt.) The stalks of common garden rhubarb are peeled, and ground or grated to a pulp, which is subjected to pressure; the juice is heated to the boiling point, neutralised with carbonate of potassa, mixed with acetate of lime, and the insoluble oxalate of lime which falls is removed by filtration; to the clear and nearly colourless liquid, solution of acetate of lead is next added as long as a precipitate (‘malate of lead’) continues to form; this is collected on a filter, washed, diffused through water, and decomposed by sulphuric acid, avoiding excess, the last portion of lead being thrown down by a stream of sulphuretted hydrogen; the filtered liquid is, lastly, carefully evaporated to the consistence of a syrup, and left in a dry atmosphere until it becomes converted into a solid and somewhat crystalline mass of malic acid. If perfectly pure malic acid is required, the malate of lead must be crystallised before decomposing it with sulphuretted hydrogen. _Prod._ 20,000 gr. of the peeled stalks yield 12,500 gr. of juice, of which one imperial gallon contains 11,139-1/4 gr. of dry malic acid.

_Obs._ By a similar process malic acid may be prepared from the juice of thee berries of the mountain ash (_Sorbus aucuparia_), just when they commence to ripen, or from the juice of apples, pears, &c.

_Prop., &c._ Malic acid is slightly deliquescent, very soluble in water, soluble in alcohol, and has a pleasant acidulous taste. The aqueous infusion soon gets mouldy by keeping. When kept fused for some time at a low heat, it is converted into fumaric acid; and when quickly distilled, it yields maleic acid, while fumaric acid is left in the retort. With the bases malic acid forms salts called malates. Of these the acid malate of ammonia is in large, beautiful crystals; malate of lead is insoluble in cold water, but dissolves in warm dilute acid, from which it separates on cooling in brilliant silvery crystals; acid malate of lime also forms very beautiful crystals, freely soluble in water; neutral malate of lime is only sparingly soluble in water; the first is obtained by dissolving the latter in hot dilute nitric acid, and allowing the solution to cool very slowly.

=MALLEABIL′ITY.= The peculiar property of metals which renders them capable of extension under the hammer.

=MALT.= _Syn._ BINA, BYNE, BRASIUM, MALTUM, L. The name given to different kinds of grain, such as barley, bere or bigg, oats, rye, maize, &c., which have become sweet, from the conversion of a portion of their starch into sugar, in consequence of incipient germination artificially produced. Barley is the grain usually employed for this purpose.

_Var._ Independently of variations of quality, or of the grain from which it is formed, malt is distinguished into varieties depending on the heat of the kiln employed for its desiccation. When dried at a temperature ranging between 90° and 120° Fahr., it constitutes ‘PALE MALT,’ when all the moisture has exhaled, and the heat is raised to from 125° to 135°, ‘YELLOW,’ or ‘PALE AMBER MALT,’ is formed; when the heat ranges between 140° and 160°, the product receives the name of ‘AMBER MALT,’ at 160° to 180°, ‘AMBER-BROWN,’ or ‘PALE BROWN MALT,’ is obtained. ROASTED, PATENT, or BLACK MALT, and CRYSTALLISED MALT, are prepared by a process similar to that of roasting coffee. The malt is placed in sheet-iron cylinders over a strong fire, and the cylinders made to revolve at the rate of about 20 revolutions per minute if roasted malt is required, or 120 for crystallised malt. In the former case the finished malt has a dark brown colour; in the latter, the interior of the grain becomes dark brown, whilst the husk assumes a pale amber hue. The temperature must never exceed 420°, or the malt will become entirely carbonised.

_Qual._ Good malt has an agreeable smell and a sweet taste. It is friable, and when broken discloses a floury kernel. Its husk is thin, clean, and unshrivelled in appearance, and the acrospire is seen extending up the back of the grain, beneath the skin. The admixture of unmalted with malted grain may be discovered, and roughly estimated, by throwing a little into water, malt floats on water, but barley sinks in it. The only certain method, however, of determining the value of malt is to ascertain the amount of soluble matter which it contains, by direct experiment. This varies from 62 to 70%, and for good malt is never less than 66 to 67%. If we assume the quarter of malt at 324 lbs., and the average quantity of soluble matter at 66%, then the total weight of soluble matter will be fully 213-3/4 lbs. per quarter; but as this, “in taking on the form of gum and sugar” during the process of mashing, “chemically combines with the elements of water, so the extract, if evaporated to dryness, would reach very nearly 231 lbs.; and this reduced to the basis of a barrel of 36 gallons, becomes in the language of the brewer, 87 lbs. per barrel, which, however, merely means that the wort from a quarter of malt, if evaporated down to the bulk of a barrel of 36 gallons, would weigh 87 lbs. more than a barrel of water.” (Ure.)

_Assay._ 1. A small quantity of the sample being ground in a coffee or pepper mill, 100 gr. are accurately weighed, and dried by exposure for about 1 hour at the temperature of boiling water. The loss in weight, in grains, indicates the quantity of moisture per cent. This, in good malt, should not exceed 6-1/2 gr.

2. A second 100 gr. is taken and stirred up with about 1/2 pint of cold water; the mixture is then exposed to the heat of boiling water for about 40 minutes; after which it is thrown on a weighed filter, and the undissolved portion washed with a little hot water; the undissolved portion, with the filter, is then dried at 212° Fahr., and weighed. The loss in weight, less the percentage of moisture last found, taken in grains, gives the percentage of soluble matter. This should not be less than 66 gr. The same result will be arrived at by evaporating the filtered liquid and ‘washings’ to dryness, and weighing the residuum.

3. A third 100 gr. is taken and mashed with about 1/2 pint of water at 160° Fahr., for 2 or 3 hours; the liquid is then drained off, the residue gently squeezed, and the strained liquid evaporated to dryness, as before, and weighed. This gives the percentage of saccharine matter, and should not be less than about 71 gr., taking the above average of malt as the standard of calculation.

_Uses, &c._ Malt is chiefly employed in the arts of brewing and distillation. Both roasted and crystallised malt are merely used to colour the worts produced from pale malt. 1 lb. of roasted malt, mashed with 79 lbs. of pale malt, imparts to the liquor the colour and flavour of ‘porter.’ The paler varieties of malt contain the largest quantity of saccharine matter. After the malt has been kiln-dried, the rootlets may be removed by means of a sieve. Before malt is mashed for beer it must be broken up, and the law requires that it be bruised or crushed by smooth metal rollers, and not ground by millstones. It has also been proposed to employ malt, instead of raw grain, for fattening domestic animals, and as food for their young and those in a sickly state. Infusion of malt (sweet wort, malt tea) is laxative, and has been recommended as an antiscorbutic and tonic. It has been given with great advantage in scurvy; but for this purpose good, well-hopped, mild beer is equally serviceable and more agreeable. See BREWING, DISTILLATION, FERMENTATION, &c.

=MALT LIQ′UORS.= The qualities of ale, beer, and porter, as beverages, the detection of their adulteration, and the methods of preparing them, are described under their respective names and in the article upon ‘BREWING’; the present article will, therefore, be confined to a short notice of the cellar management, and the diseases of malt liquors generally.

AGE. The appearance and flavour to which this term is applied can, of course, be only given to the liquor by properly storing it for a sufficient time. Fraudulent brewers and publicans, however, frequently add a little oil of vitriol (diluted with water) to new beer, by which it assumes the character of an inferior liquor of the class 1 or 2 years old. Copperas, alum, sliced onions, Seville oranges, and cucumbers, are also frequently employed by brewers for the same purpose.

BOTTLING. Clean, sweet, and dry bottles, and sound and good corks, should be had in readiness. The liquor to be bottled should be perfectly clear; and if it be not so, it must be submitted to the operation of ‘fining.’ When quite fine, and in good condition, the bung of the cask should be left out all night, and the next day the liquor should be put into bottles, which, after remaining 12 or 24 hours, covered with sheets of paper to keep out the flies and dust, must be securely corked down. Porter is generally wired over. The wire for this purpose should be ‘annealed,’ and not resilient. If the liquor is intended for exportation to a hot climate, the bottles should remain filled for 2 or 3 days, or more, before corking them. The stock of bottled liquor should be stored in a cool situation; and a small quantity, to meet present demands only, should be set on their sides in a warmer place to ripen. October beer should not be bottled before Midsummer, nor March beer till Christmas.

CLOUDINESS. Add a handful of hops boiled in a gallon of the beer, and in a fortnight fine it down.

FINING. See CLARIFICATION and BREWING.

FLATNESS. When the liquor is new, or has still much undecomposed sugar left in it, a sufficient remedy is to remove it into a warmer situation for a few days. When this is not the case, 2 or 3 pounds of moist sugar (foots) may be ‘rummaged’ into each hogshead. In this way a second fermentation is set up, and in a few days the liquor becomes brisk, and carries a head. This is the plan commonly adopted by publicans. On the small scale the addition of a few grains of carbonate of soda, or of prepared chalk, to each glass, is commonly made for the same purpose; but in this case the liquor must be drunk within a few minutes, else it becomes again flat and insipid. This may be adopted for home-brewed beer which has become sour and vapid.

FOXING OR BUCKING. The spontaneous souring of worts or beer during their fermentation or ripening, to which this name is applied, may generally be remedied by adding to the liquor some fresh hops (scalded), along with some black mustard seed (bruised). Some persons use a little made mustard, or a solution of alum or of catechu, and in a week or 10 days afterwards further add some treacle, or moist sugar.

Frosted beer is recovered by change of situation; by the addition of some hops boiled in a little sweet wort; or by adding a little moist sugar or treacle to induce a fresh fermentation.

HEADING. This is added to thin and vapid beer to make it bear a frothy head. The most innocent, pleasant, and effective addition of this sort is a mixture of pure ammonio-citrate of iron and salt of tartar, about equal parts in the proportion of only a few grains to a quart.

IMPROVING. This is the trade synonym of ‘ADULTERATION’ and ‘DOCTORING,’ Nevertheless there are cases in which ‘improvement’ may be made without affecting the wholesome character of the liquor. Of this kind is the addition of hops, spices, &c., during the maturation of beer that exhibits a tendency to deteriorate. For this purpose some persons cut a half quartern loaf into slices, and after toasting them very high, place them in a coarse linen bag along with 1/2 lb. of hops, and 2 oz. each of bruised ginger, cloves, and mustard seed, and suspend the bag by means of a string a few inches below the surface of the beer (a hogshead), which is then bunged close. The addition of a little ground capsicum in the same way is also a real improvement to beer, when judiciously made.

MUSTINESS. To each hogshead, racked into clean casks, add 1 lb. of new hops boiled in a gallon of the liquor, along with 7 lbs. of newly-burnt charcoal (coarsely bruised, and the fine dust sifted off), and a 4-lb. loaf of bread cut into thin slices and toasted rather black; ‘rouse up’ well every day for a week, then stir in of moist sugar 3 or 4 lbs., and bung down for a fortnight.

RECOVERING. This is said of unsaleable beer when rendered saleable, by giving it ‘head’ or removing its ‘tartness.’

RIPENING. This term is applied to the regular maturation of beer. It is also used to express the means by which liquors already mature are rendered brisk, sparkling, or fit and agreeable for immediate use. In the language of the cellar, malt liquors are said to be ‘up’ when they are well charged with gaseous matter, and bear a frothy head. These qualities depend on the undecomposed sugar undergoing fermentation, which, when active, can only be of comparatively short duration, and should, therefore, be repressed rather than excited in beers not required for immediate consumption. When we desire to give ‘briskness’ to these liquors, whether in cask or bottle, it is only necessary to expose them for a few days to a slight elevation of temperature, by removing them, for instance, to a warmer apartment. This is the plan successfully adopted by bottlers. The addition of a small lump of white sugar to each bottle of ale or beer, or a teaspoonful of moist sugar to each bottle of porter, just before corking it, will render it fit for drinking in a few days in ordinary weather, and in 2 or 3 days in the heat of summer. A raisin or a lump of sugar candy is often added to each bottle with a like intention. The Parisians bottle their beer one day and sell it the next. For this purpose, in addition to the sugar as above, they add 2 or 3 drops of yeast. Such bottled liquor must, however, be drunk within a week, or else stored in a very cold place, as it will otherwise burst the bottles or blow out the corks.

ROPINESS. A little infusion of catechu or of oak bark, and some fresh hops, may be added to the beer, which in a fortnight should be rummaged well, and the next day ‘fined’ down.

SOURNESS. Powdered chalk, carbonate of soda, salt of tartar, or pearlash, is commonly added by the publicans to the beer, until the acidity is nearly removed, when 4 or 5 lbs. of moist sugar or foots per hogshead are ‘rummaged’ in, together with sufficient water to disburse double the amount of the outlay and trouble. Such beer must be soon put on draught, as it is very apt to get flat by keeping. Oyster shells and egg shells are also frequently used by brewers for the same purpose. To remove the acidity of beer, on the small scale, a few grains of carbonate of soda per glass may be added just before drinking it.

STORING. The situation of the beer-cellar should be such as to maintain its contents at a permanently uniform temperature, ranging between 44° and 50° Fahr., a condition which can only be ensured by choosing for its locality an underground apartment, or one in the centre of the basement portion of a large building.

VAMPING. Half fill casks with the old liquor, fill them up with some newly brewed, and bung close for 3 weeks or a month.

=MALTIN.= A nitrogenous ferment obtained from malt, which it is believed by Dubrunfaut to be the active principle, and is more energetic than diastase. The above chemist states it may be precipitated from extract of malt, by the addition of two molecules of alcohol at 90 per cent. According to Dubrunfaut maltin exists in all cereal grains, and in the water of rivers and brooks; but not in the well water of Paris.

=MALTING.= The method of converting barley, wheat, oats, or any other description of grain into malt. There are four successive stages in the process of malting, viz., steeping, couching, flooring, and kiln-drying.

1. _Steeping or moistening._——The grain is placed in a large wooden or stone cistern, and sufficient water run in to cover it. Here it remains for a period of from 40 to 60 hours, depending on the temperature of the weather, or until it becomes soft enough to be easily pierced with a needle, or crushed between the thumb and finger without yielding a milky juice. While in steep the grain swells, increasing nearly one fifth in bulk, and about 50 per cent. in weight. The water is then drained off, and the grain is ready for the next operation.

2. _Couching or germinating._——From the cistern the swollen barley is thrown out into the couch frame to the depth of from 14 or 20 inches, where heat is generated and germination induced. Here it is allowed to remain for from 20 to 30 hours, according to the state of the weather, until the acrospire or pumule shoots forth. Were the grain to remain long in the couch, particularly in warm weather, it would be either unduly forced or turn sour. Whilst in couch it rises in temperature about 15 degrees, and gives off some of its extra moisture. This is called sweating, and as the rootlets now begin to shoot out, means must be taken to check the germination.

3. _Flooring or regulating._——This consists in spreading the heated barley on the floor at different depths, according as it is required to increase or retard germination. During this stage of the operation the art of the maltster may be more properly said to commence, as now all his judgment is brought into requisition. The grain must be turned three or four times a day, and at each turning the layer is spread out more and more, until it is reduced to the depth of about three or four inches. The chief object to be attained by this operation is a regular germination of the grain.

4. _Kiln-drying._——The sprouted barley is next spread in a thin layer on the malt kiln, and heat applied. The temperature to which the kiln is raised varies according to the purpose for which the malt is required, the difference between pale, amber, and brown malt depending solely on the degree of heat to which each has been subjected, and the manner in which the heat has been applied (see MALT). If the malt were not kiln-dried it would not keep, but would become mouldy. By the process of drying, the vitality of the seed is destroyed, and it may then be preserved without suffering further change.

_Product._——Good barley yields about 80% by weight and 109% by measure, of dried and sifted malt. Of the loss by weight 12% must be referred to water existing in the raw grain.

=MAN′′GANESE.= Mn. _Syn._ MANGANESIUM, L. A hard, brittle metal, discovered by Gahn in the black oxide of manganese of commerce.

_Prep._ Reduce manganous carbonate to fine powder, make it into a paste with oil, adding about 1-10th of its weight of calcined borax, place the mixture in a Hessian crucible lined with charcoal, lute on the cover, and expose it to the strongest heat of a smith’s forge for 2 hours; when cold, break the crucible and preserve the metallic button in naphtha.

_Obs._ The product is probably a carbide of manganese, just as steel is a carbide of iron. Deville has lately prepared pure manganese by reducing the pure oxide by means of an insufficient quantity of sugar charcoal in a crucible made of caustic lime.

_Prop._ As prepared by Deville, metallic manganese has a reddish lustre, like bismuth; it is very hard and brittle; when powdered, it decomposes water, even at the lowest temperature. Dilute sulphuric acid dissolves it with great energy, evolving hydrogen. Sp. gr. 7·13. In an oxidised state manganese is abundant in the mineral kingdom, and traces of it have been found in the ashes of plants and in mineral waters.

The salts of manganese may be easily prepared in a state of purity by dissolving the precipitated carbonate in the acids. Most of them are soluble, and several are crystallisable.

_Tests._ Manganous salts are distinguished as follows:——The hydrates of potassium and sodium give white precipitates insoluble in excess, and rapidly turning brown. The presence of ammonium salts interferes with these tests. Ammonia gives similar results.

Ferrocyanide of potassium gives a white precipitate. Sulphuretted hydrogen gives no precipitate in acid solutions, and precipitates neutral solutions only imperfectly; but in alkaline solutions it gives a bright, flesh-coloured, insoluble precipitate, which becomes dark brown on exposure to the air. Sulphide of ammonium, in neutral solutions, also yields a similar precipitate, which is very characteristic. A compound of manganese fused with borax in the outer flame of the blowpipe gives a bead, which appears of a violet-red colour whilst hot, and upon cooling acquires an amethystine tint; this colour is lost by fusion in the inner flame. Heated upon platinum foil with a little carbonate of sodium, in the outer flame, it yields a green mass whilst hot, which becomes bluish green when cold.

=Manganous Ace′tate.= Mn(C_{2}H_{3}O_{2})_{2}. _Syn._ ACETATE OF PROTOXIDE OF MANGANESE; MANGANII ACETAS, L. _Prep._ 1. By neutralising concentrated acetic acid with manganous carbonate, and evaporating the solution so that crystals may form.

_Prop., &c._ The crystals, when pure, are of a pale red colour; permanent in the air; soluble in alcohol, and 3-1/2 parts of water, and possess an astringent and metallic taste.——_Dose_, 5 to 10 gr., as an alterative, hæmatinic, &c.

=Manganous Car′bonate.= MnCO_{3}. _Syn._ CARBONATE OF PROTOXIDE OF MANGANESE; MANGANESII CARBONAS, L. _Prep._ Reduce the black oxide of manganese of commerce to fine powder, and after washing it in water acidulated with hydrochloric acid, dissolve it in strong hydrochloric acid, and evaporate the resulting solution to dryness; dissolve the residue in water, and add to the solution sufficient sodium carbonate to precipitate all the iron present; digest the mixed precipitate in the remainder of the liquid, filter, add ammonium sulphide until it begins to produce a flesh-coloured precipitate, then filter, and add sodium carbonate as long as a precipitate falls; lastly, well wash the newly-formed carbonate in water, and dry it by a gentle heat.

2. By directly precipitating a solution of the chloride with sodium carbonate, and washing and drying the powder as before.

_Prop., &c._ A pale buff or cream-coloured powder; insoluble in water; freely soluble in acids; exposed to a strong heat, it loses its carbonic acid, absorbs oxygen, and is converted into the red oxide. It is chiefly employed in the preparation of the other salts of manganese.

=Manganous Chlo′′ride.= MnCl_{2}. _Syn._ PROTOCHLORIDE OF MANGANESE, MURIATE OF M.; MANGANESII CHLORIDUM, L. _Prep._ 1. By saturating hydrochloric acid with manganous carbonate; the solution is greatly concentrated by evaporation, when crystals may be obtained, or it is at once evaporated to dryness; in either case the product must be placed in warm, dry, stoppered bottles, and preserved from the air.

2. From the dark brown residual liquid of the process of obtaining chlorine from binoxide of manganese and hydrochloric acid; this liquid is evaporated to dryness, and then slowly heated to dull redness in an earthen vessel, with constant stirring, and kept at that temperature for a short time; the greyish-looking powder thus obtained is treated with water, and the solution separated from the ferric oxide and other insoluble matter by filtration; if any iron still remains, a little manganous carbonate is added, and the whole boiled for a few minutes; the filtered solution is then treated as before. This is the least expensive and most convenient source of this salt.

_Prop., &c._ Rose-coloured tabular crystals; inodorous; very soluble both in water and alcohol; very deliquescent; when gradually heated to fusion the whole of the water is expelled, and at a red heat it slowly suffers decomposition. Astringent, tonic, hæmatinic, and alterative.——_Dose_, 3 to 10 gr.; in scorbutic, syphilitic, and certain chronic cutaneous affections; anæmia, chlorosis, &c.

=Manganous Hydrate.= Mn(HO)_{2}. _Syn._ HYDRATED PROTOXIDE OF MANGANESE. _Prep._ Formed by adding potassium hydrate to manganous sulphate, and filtering and drying the precipitate in vacuo. White powder rapidly absorbing oxygen and burning first green and then brown from formation of higher oxides.

=Manganous I′odide.= MnI_{2}. _Syn._ MANGANESII IODIDUM, L. _Prep._ By dissolving the carbonate in hydriodic acid and evaporating the filtered liquid in vacuo or out of contact with air.——_Dose_, 1 to 3 gr.; in anæmia, chlorosis, &c., occurring in scrofulous subjects.

=Manganous Oxide.= MnO. _Syn._ PROTOXIDE OF MANGANESE. _Prep._ By passing a current of hydrogen over manganous carbonate heated to whiteness in a porcelain tube. Olive-green powder rapidly oxidising on exposure to air, and soluble in acids forming manganous salts.

There are four other oxides and two oxyhydrates that may be treated of here, but of which only the peroxide and the manganates and permanganates are of practical importance.

=Manganous-manganic Oxide.= Mn_{3}O_{4}, or MnO.Mn_{2}O_{3}. _Syn._ RED OXIDE OF MANGANESE, PROTOSESQUIOXIDE OF MANGANESE. Found native as “Hansmanite”. It is produced by igniting manganous carbonate, or manganic oxide, or manganic peroxide. Reddish-brown, coloured crystals or powder, and communicates an amethyst colour to glass when fused with it.

=Manganous-manganic Peroxide.= Mn_{4}O_{7} or MnO_{3}.Mn_{2}O_{3}. _Syn._ INTERMEDIATE, OXIDE OF MANGANESE. Found native as “Varvicile,” as a black hard crystalline mass. Decomposed when heated into a lower oxide and oxygen.

=Manganous Phosphate.= MnH.PO_{4} + 6Aq. _Syn._ PHOSPHATE OF PROTOXIDE OF MANGANESE; MANGANESII PHOSPHAS, L. _Prep._ By precipitating a solution of manganous sulphate with a solution of sodium phosphate. It must be preserved from the air.——_Dose_, 3 to 12 gr.; in anæmia, rickets, &c.

=Manganous Sul′phate.= MnSO_{4}. _Syn._ SULPHATE OF PROTOXIDE OF MANGANESE; MANGANESII SULPHAS, L. _Prep._ 1. By dissolving manganous carbonate in dilute sulphuric acid, and evaporating the filtered solution so that crystals may form, or at once gently evaporating it to dryness. Pure.

2. (Commercial.) By igniting manganic peroxide (pyrolusite) mixed with about 1-10th of its weight of powdered coal in an iron crucible or gas-retort, and digesting the residuum of the calcination in sulphuric acid, with the addition after a time of a little hydrochloric acid; the solution of manganous sulphate thus obtained, after defecation, is evaporated to dryness, and heated to redness as before; the mass, after ignition, is crushed small, and treated with water; the solution is nearly pure, the whole of the iron having been reduced into the state of insoluble peroxide. Used by the calico printers. Cloth steeped in the solution, and afterwards passed through a solution of chloride of lime, is dyed of a permanent brown.

_Prop., &c._ Pale rose-coloured crystals of the formulæ MnSO_{4}, 7Aq.; MnSO_{4}, 5Aq.; or MnSO_{4}, 4Aq.; according to the method of crystallising, furnishing a solution of a rich amethystine colour. With sulphate of potassa it forms a double salt (‘manganese alum’).——_Dose._ As an alterative and tonic, 5 to 10 gr.; as a cholagogue cathartic, 1 to 2 dr., dissolved in water, either alone or combined with infusion of senna. According to Ure, its action is prompt and soon over; 1 dr. of it occasions, after the lapse of an hour or so, one or more liquid bilious stools. In large doses it occasions vomiting, and in excessive doses it destroys life by its caustic action on the stomach. (Dr G. C. Mitscherlich.) It has been administered with manifest advantage in torpor of the liver, gout, jaundice, syphilis, and certain skin diseases; and, combined with iron, in anæmia, chlorosis, rickets, &c.

=Manganous Tar′trate.= MnC_{4}H_{4}O_{6}. _Syn._ MANGANESII TARTRAS, L. _Prep._ By saturating a solution of tartaric acid with most manganous carbonate. Alterative and tonic.——_Dose_, 4 to 12 gr.

=Manganate of Barium.= BaMnO_{4}. Green insoluble powder, obtained by fusing barium hydrate, potassium chlorate, and manganic peroxide together, and washing the product.

=Manganate of Potassium.= K_{2}MnO_{4}. Finely powdered manganic peroxide, potassium chlorate, and potassium hydrate, made into a thick paste with water, and heated to dull redness. The fused product is treated with a small quantity of water, and crystallised by evaporation in vacuo.

Dark green, almost black crystals, readily soluble in water, but decomposed by excess, or by acids into manganic peroxide, and potassium permanganate.

=Manganate of Sodium.= Na_{2}MnO_{4}. Prepared on the large scale by heating a mixture of manganic peroxide and sodium hydrate to redness in a current of air. Used in strong solution as a disinfectant under the name of “Condy’s green fluid.”

=Manganic Acid.= H_{2}MnO_{4}. This acid has not yet been obtained free, but some of its salts are extensively employed as disinfectants, as “green Condy’s fluid.” The chief compounds are the following:——

=Manganic Hydrate.= Mn_{2}(HO)_{6}. _Syn._ HYDRATED SESQUIOXIDE OF MANGANESE. Found native as “manganite,” in reddish-brown crystals. _Prep._ By passing a current of air through recently precipitated and moist manganous hydrate. Soft dark brown powder converted into the oxide by heat.

=Manganic Oxide.= Mn_{2}O_{3}. _Syn._ SESQUIOXIDE OF MANGANESE. Found native as “Braumite,” and readily formed by exposing manganous hydrate to the action of air, and drying, or by gently igniting the peroxide brown or black powder decomposed by heat.

=Manganic Peroxide.= MnO_{2}. _Syn._ PERMANGANIC OXIDE, BINOXIDE OF MANGANESE, PEROXIDE OF MANGANESE, BLACK OXIDE OF MANGANESE, OXIDE OF MANGANESE, MANGANESII OXIDUM NIGRUM (B. P.), MANGANESII BINOXYDUM (Ph. L.), MANGANESE OXYDUM (Ph. E.).

It is the only oxide of manganese that is directly employed in the arts. It is a very plentiful mineral production, and is found in great abundance in some parts of the West of England. The manganese of the shop is prepared by washing, to remove the earthy matter, and grinding in mills. The blackest samples are esteemed the best. It is chiefly used to supply oxygen gas, and in the manufacture of glass and chlorine; in dyeing and to form the salts of manganese. It has been occasionally employed in medicine, chiefly externally in itch and porrigo, made into an ointment with lard. It has been highly recommended by Dr Erigeler in scrofula. Others have employed it as an alterative and tonic with variable success. When slowly introduced into the system during a lengthened period, it is said to produce paralysis of the motor nerves. (Dr Coupar.)——_Dose_, 3 to 12 gr., or more, thrice daily, made into pills.

_Pur._ Native binoxide of manganese (pyrolusite) is usually contaminated with variable proportions of argillaceous matter, calcium carbonate, ferric oxide, silica, and barium sulphate, all of which lower its value as a source of oxygen, and for the preparation of chlorine. The richness of this ore can, therefore, be only determined by an assay for its principal ingredient.

_Assay._ There are several methods adopted for this purpose, among which the following recommend themselves as being the most accurate and convenient.

1. A portion of the mineral being reduced to very fine powder, 50 gr. of it are put into the little apparatus employed for the analysis of carbonates described at page 406, together with about 1/2 fl. oz. of cold water, and 100 gr. of strong hydrochloric acid, the latter contained in the little tube (_b_); 50 gr. of crystallised oxalic acid are then added, the cork carrying the chloride of calcium tube fitted in, and the whole quickly and accurately weighed or counterpoised; the apparatus is next inclined so that the acid contained in the small tube may be mixed with the other contents of the flask, and the reaction of the ingredients is promoted by the application of a gentle heat; the disengaged chlorine resulting from the mutual decomposition of the hydrochloric acid and the manganic peroxide converts the oxalic acid into carbonic acid gas, which is dried in its passage through the chloride of calcium tube before it escapes into the air. As soon as the reaction is complete, and the residual gas has been driven off by a momentary ebullition, the apparatus is allowed to cool, when it is again carefully and accurately weighed. The loss of weight in grains, if doubled, at once indicates the percentage richness of the mineral examined in manganic peroxide; or, more correctly, every grain of carbonic anhydride evolved represents 1·982 gr. of the peroxide.

2. (Fresenius and Will.) The apparatus employed is the ‘alkalimeter’ figured at page 30. The operation is similar to that adopted for the assay of alkalies, and is a modification of the oxalic acid and sulphuric acid test for manganese, originally devised by M. Berthier. The standard weight of manganic peroxide recommended to be taken by Fresenius and Will is 2·91 grammes, along with 6·5 to 7 grammes of neutral potassium oxalate. The process, with quantities altered to adapt it for employment in the laboratories of these countries, is as follows:——Manganic peroxide (in very fine powder), 50 gr.; neutral potassium oxalate (in powder), 120 gr.; these are put into the flask _A_ (see _engr._, p. 31), along with sufficient water to about 1-4th fill it; the flask _A_ and _B_ (the latter containing the sulphuric acid) are then corked air-tight, and thus connected in one apparatus, the whole is accurately weighed. The opening of the tube _b_ being closed by a small lump of wax, a little sulphuric acid is sucked over from the flask _B_ into the flask _A_; the disengagement of oxygen from the manganese immediately commences and this reacting upon the oxalic acid present, converts it into carbonic anhydride gas, which passing through the concentrated sulphuric acid in the flask _B_, which robs it of moisture, finally escapes from the apparatus through the tube _d_. As soon as the disengagement of carbonic acid ceases, the operator sucks over a fresh portion of sulphuric acid, and this is repeated at short intervals, until bubbles of gas are no longer disengaged. The little wax stopper is now removed, and suction is applied at _h_ until all the carbonic acid in the apparatus is replaced by common air. When the whole has become cold it is again weighed. The loss of weight, doubled, indicates the amount of pure manganic peroxide, in the sample, as before.

3. (Otto.) 50 gr. of the sample reduced to very fine powder are mixed in a glass flask, with hydrochloric acid 1-1/2 fl. oz., diluted with 1/2 oz. of cold water, and portions of ferrous sulphate, from a weighed sample, immediately added, at first in excess, but afterwards in smaller doses, until the liquid ceases to give a blue precipitate with red prussiate of potash, or to evolve the odour of chlorine; heat being employed towards the end of the process. The quantity of ferrous sulphate consumed is now ascertained by again weighing the sample. If the peroxide examined was pure, the loss of weight will be 317 gr.; but if otherwise, the percentage of the pure peroxide may be obtained by the rule of three. Thus: suppose only 298 gr. of the sulphate were consumed, then

317 : 100 :: 298 : 94,

and the richness of the sample would be 94%. The percentage value of the oxide for evolving chlorine may be obtained by multiplying the weight of the consumed ferrous sulphate by ·2588, which, in the above case, would give 76% of chlorine. For this purpose, as well as for chlorometry, the ferrous sulphate is best prepared by precipitating it from its aqueous solution with alcohol, and drying it out of contact with air until it loses its alcoholic odour.

_Obs._ Before applying the above processes it is absolutely necessary that we ascertain whether the peroxide examined contains any carbonates, as the presence of these would vitiate the results. This is readily determined by treating it with a little dilute nitric acid:——if effervescence ensues, one or more carbonates are present, and the sample, after being weighed, must be digested for some time in dilute nitric acid in excess, and then carefully collected on a filter, washed, and dried. It may then be assayed as before. The loss of weight indicates the quantity of carbonates present, with sufficient accuracy for technical purposes. The determination of this point is the more important, as these contaminations not merely lessen the richness of the mineral in pure manganic peroxide, but also cause a considerable waste of acid when it is employed in the manufacture of chlorine.

=Permanganic Acid.= HMnO_{4}. Obtained by distilling cautiously potassium permanganate and sulphuric acid. Dark violet-black liquid, green by reflected light, and rapidly absorbing water forming a violet solution. Oxidises organic matter with explosive violence.

=Permanganate of Barium.= Ba(MnO)_{45}. Black soluble prisms, formed by decomposing silver permanganate by means of barium chloride, and cautiously evaporating.

=Permanganate of Potassium.= KMnO_{4}. _Prep._ Potassium chlorate, or nitrate, and potassium hydrate are made into a paste with water, and manganic peroxide added; the mass is dried and heated to redness. The residue is boiled with water, filtered through asbestos, and evaporated down and recrystallised.

Dark purple, red, almost black anhydrous long prisms, readily soluble in 16 pints of water. Decomposed in presence of acids by most organic matter.

=Permanganate of Silver.= AgMnO_{4}. _Prep._ Precipitate a strong solution of silver nitrate by means of a concentrated solution of potassium permanganate. Small black prisms, soluble in 100 parts of water, with a purple colour.

=Permanganate of Sodium.= NaMnO_{4}. Obtained as a dark purple liquid by passing a current of carbonic anhydride through sodium manganate. Condy’s red fluid is chiefly a sodium permanganate dissolved in water.

=MANGE.= An eruptive disease, corresponding to the itch in man, resulting from the burrowing into the skin of minute animalcules (mites or _acari_), and common to several domestic animals, more especially the dog and horse. Like the itch, it is contagious. The causes are confinement, dirt, and bad living. The treatment should consist in the immediate removal of the cause, the frequent use of soft soap and water, followed by frictions with sulphur ointment, solution of chloride of lime or sporokton, the administration of purgatives, and a change to a restorative diet. Dun states that in India a very efficient remedy for mange is employed by the native farriers, which consists of castor oil seeds well bruised, steeped for twelve hours in sour milk, and rubbed into the skin, previously thoroughly cleansed with soap and water. “The itchiness disappears almost immediately and the acari are speedily destroyed.” A dressing consisting of 1 oz. of chloride of zinc (Burnett’s disinfectant fluid) and 1 quart of water may also be applied with advantage.

=MAN′′GEL WUR′ZEL.= _Syn._ MANGOLD-WURZEL, HYBRID BEET, ROOT OF SCARCITY. The _Beta vulgaris_, var. _campestris_, a variety of the common beet. The root abounds in sugar, and has been used in Germany as a substitute for bread in times of scarcity. In these countries it is chiefly cultivated as food for cattle. The young leaves are eaten as spinach. The percentage composition of mangold wurzel is as follows:——Flesh-formers (albumenoid bodies), 1·54; heat and fat-formers (sugar, &c.) 8·60; indigestible fibre, 1·12; ash, 0·96; 87·78.

=MAN′HEIM GOLD.= A gold-coloured brass. See GOLD (Dutch).

=MAN′NA= _Syn._ MANNA (B. P., Ph. L., E., & D.), L. A concrete exudation from the stem of _Fraxinus ornus_ and _F. rotundifolia_, obtained by incision. (B. P.) “The juice flowing from the incised bark” of “_Fraxinus rotundifolia_ and _F. ornus_, hardened by the air.” (Ph. L.) The finest variety of this drug is known as flake manna, and occurs in pieces varying from 1 to 6 inches long, 1 or 2 inches wide, and 1/2 to 1 inch thick. It has a yellowish-white or cream colour; an odour somewhat resembling honey, but less pleasant, a sweet, mawkish taste; and is light, porous, and friable. It is laxative in doses of 1 to 2 oz.

=Manna Factitious=, made of a mixture of sugar, starch, and honey, with a very small quantity of scammony to give it odour and flavour, and to render it purgative, has been lately very extensively offered in trade, and met with a ready sale.

=MAN′NACROUP.= A granular preparation of wheat deprived of bran, used as an article of food for children and invalids. (Brande.)

=MAN′NITE.= C_{6}H_{14}O_{6}. _Syn._ MANNA SUGAR, MUSHROOM S.; MANNITA, L. A sweet, crystallisable substance, found in manna and in several other vegetable productions. It has been formed artificially by the action of sodium-amalgam upon an alkaline solution of cane sugar.

_Prep._ 1. Digest manna in boiling rectified spirit, and filter or decant the solution whilst hot; the mannite crystallises as the liquid cools in tufts of slender, colourless needles.

2. (Ruspini.) Manna, 6 lbs.; cold water (in which the white of an egg has been beaten), 3 lbs.; mix, boil for a few minutes, and strain the syrup through linen whilst hot; the strained liquid will form a semi-crystalline mass on cooling; submit this to strong pressure in a cloth, mix the cake with its own weight of cold water, and again press it; dissolve the cake thus obtained in boiling water, add a little animal charcoal, and filter the mixture into a porcelain dish set over the fire; lastly, evaporate the filtrate to a pellicle, and set the syrup aside to crystallise. Large quadrangular prisms; perfectly white and transparent.

_Prop., &c._ Mannite has a powerfully sweet and agreeable taste; dissolves in 5 parts of cold water and about half that quantity of boiling water; freely soluble in hot, and slightly so in cold alcohol; fuses by heat without loss of weight; with sulphuric acid it combines to form a new acid compound. It is distinguished from the true sugars by its aqueous solution not being susceptible of the vinous fermentation, and not possessing the property of rotary polarisation. When pure, it is perfectly destitute of purgative properties. It is now extensively imported from Italy, and is chiefly used to cover the taste of nauseous medicines, and as a sweetmeat.

=MANURES′.= Substances added to soils to increase their fertility. The food of vegetables, as far as their organic structure is concerned, consists entirely of inorganic compounds; and no organised body can serve for the nutrition of vegetables until it has been, by the process of decay, resolved into certain inorganic substances. These are carbonic acid, water, and ammonia, which are well known to be the final products of putrefaction. But even when these are applied to vegetables, their growth will not proceed unless certain mineral substances are likewise furnished in small quantities, either by the soil or the water used to moisten it. Almost every plant, when burned, leaves ashes, which commonly contain silica, potassa, and phosphate of lime; often, also, magnesia, soda, sulphates, and oxide of iron. These mineral bodies appear to be essential to the existence of the vegetable tissues; so that plants will not grow in soils destitute of them, however abundantly supplied with carbonic acid, ammonia, and water. The carbon of plants is wholly derived from carbonic acid, which is either absorbed from the atmosphere, and from rain water, by the leaves, or from the moisture and air in the soil, by the roots. Its carbon is retained and assimilated with the body of the plant, while its oxygen is given out in the gaseous form; this decomposition being always effected under the influence of light at ordinary temperatures. The hydrogen and oxygen of vegetables, which, when combined with carbon, constitute the ligneous, starchy, gummy, saccharine, oily, and resinous matters of plants, are derived from water chiefly absorbed by the roots from the soil. The nitrogen of vegetables is derived chiefly, if not exclusively, from ammonia, which is supplied to them in rain, and in manures, and which remain in the soil till absorbed by the roots.

According to the celebrated ‘mineral theory’ of agriculture advanced by Liebig a soil is fertile or barren for any given plant according as it contains those mineral substances that enter into its composition. Thus, “the ashes of wheat-straw contain much silica and potassa, whilst the ashes of the seeds contain phosphate of magnesia. Hence, if a soil is deficient in any one of these, it will not yield wheat. On the other hand, a good crop of wheat will exhaust the soil of these substances, and it will not yield a second crop till they have been restored, either by manure or by the gradual action of the weather in disintegrating the subsoil. Hence the benefit derived from fallows and from the rotation of crops.

“When, by an extraordinary supply of any one mineral ingredient, or of ammonia, a large crop has been obtained, it is not to be expected that a repetition of the same individual manure next year will produce the same effect. It must be remembered that the unusual crop has exhausted the soil probably of all the other mineral ingredients, and that they also must be restored before a second crop can be obtained.

“The salt most essential to the growth of the potato is the double phosphate of ammonia and magnesia; that chiefly required for hay is phosphate of lime; while for almost all plants potassa and ammonia are highly beneficial.”

From these principles we “may deduce a few valuable conclusions in regard to the chemistry of agriculture. First, by examining the ashes of a thriving plant, we discover the mineral ingredients which must exist in a soil to render it fertile for that plant. Secondly, by examining a soil, we can say at once whether it is fertile in regard to any plants the ashes of which have been examined. Thirdly, when we know the defects of a soil, the deficient matters may be easily obtained and added to it, unmixed with such as are not required. Fourthly, the straw, leaves, &c., of any plant, are the best manure for that plant, since every vegetable extracts from the soil such matters alone as are essential to it. This important principle has been amply verified by the success attending the use of wheat-straw, or its ashes, as manure for wheat, and of the chippings of the vines as a manure for the vineyard. When these are used (in the proper quantity) no other manure is required. Fifthly, in the rotation of crops, those should be made to follow which require different materials; or a crop which extracts little or no mineral matter, such as peas, should come after one which exhausts the soil of its phosphates and potassa.” (Liebig.)

The experiments of Messrs Lawes and Gilbert have forced upon them opinions differing from those of Baron Liebig on some important points in relation to his ‘mineral theory,’ which endeavours to prove that “the crops on a field diminish or increase in exact proportion to the diminution or increase of the mineral substances conveyed to it in manure.” The results obtained by the English investigators appear to prove that it is impossible to get good crops by using mineral manures alone, and that nitrogenous manures (farm-yard manure, guano, ammoniacal salts, &c.) are fertilising agents of the highest order.

Of the chemical manures now so much used bone-dust is, perhaps, the most important, as it supplies the phosphates which have been extracted by successive crops of grass and corn, the whole of the bones of the cattle fed on these crops having been derived from the soil; its gelatin also yields ammonia by putrefaction. Guano acts as a source of ammonia, containing much oxalate and urate of ammonia, with some phosphates. Nightsoil and urine, especially the latter, are most valuable for the ammonia they yield, as well as for the phosphates and potassa; but are very much neglected in this country, although their importance is fully appreciated in Belgium, France, and China. Nitrate of soda is valued as a source of nitrogen.

All organic substances may be employed as manures; preference being, however, given to those abounding in nitrogen, and which readily decay when mixed with the soil.

The analysis of manures, soils, and the ashes of plants, for the purpose of ascertaining their composition and comparative value, is not easily performed by the inexperienced; but a rough approximation to their contents, sufficiently accurate for all practical purposes, may be generally made by any intelligent person with proper care and attention. See AGRICULTURE, BONE-DUST, GUANO, &c.

=Manures, Artificial.= Various formulæ belonging to this head will be found dispersed, under their respective names, throughout this work. The following are additional ones:——

1. (Anderson.) Sulphate of ammonia, common salt, and oil of vitriol, of each 10 parts; chloride of potassium, 15 parts; gypsum and sulphate of potassa, of each 17 parts; saltpetre, 20 parts; crude Epsom salts, 25 parts; sulphate of soda, 33 parts. For clover.

2. (Huxtable.) Crude potash, 28 lbs.; common salt, 1 cwt.; bone-dust and gypsum, of each 2 cwt.; wood-ashes, 15 bushels. For either corn, turnips, or grass.

3. (Johnstone.) Sulphate of soda (dry), 11 lbs.; wood-ashes, 28 lbs.; common salt, 3/4 cwt.; crude sulphate of ammonia, 1 cwt.; bone-dust, 7 bushels. As a substitute for guano.

4. (Lawes’ ‘Superphosphate.’) See COPROLITE.

5. (Fertilising powder.) A mixture of very fine bone-dust, 18 parts; calcined gypsum, and sulphate of ammonia, of each 1 part. The seed is ordered to be steeped in the ‘drainings’ from a dunghill, and after being drained, but whilst still wet, to be sprinkled with the powder, and then dried. See FLOWERS, LIME (Superphosphate), &c.

=MANUSCRIPTS, Faded, to Restore.= One of the methods in use for the restoration of old or faded writing is to expose it to the vapours of hydrosulphate of ammonia (hydrosulphide of ammonium) until the ink becomes darkened by the formation of sulphide of iron. Another consists in carefully washing, or sponging, the faded manuscript over with a weak solution of the ammonic sulphide, and as soon as the characters become legible, soaking it in water so as to remove the remaining sulphide, and then drying it between folds of blotting paper. A third plan, and one attended with less risk to the paper, is to brush over the manuscript with a moderately strong aqueous solution of gallo-tannic acid, to wash with water, and afterwards to dry it at a temperature of about 150° Fahr.

The solution of gallo-tannic acid may be obtained by making a strong infusion of bruised nutgalls in boiling water, and when cold, straining it. Some old and mediæval manuscripts are written in inks made of carbon. To such the above treatment is inapplicable; being suited only to those traced in ordinary writing ink. For parchments the latter method is preferable.

=MAPS.= These, as well as architect’s and engineer’s designs, plans, sections, drawings, &c., may be tinted with any of the simple liquid colours mentioned under ‘VELVET COLOURS,’ preference being given to the most transparent ones, which will not obscure the lines beneath them. To prevent the colours from sinking and spreading, which they usually do on common paper, the latter should be wetted 2 or 3 times with a sponge dipped in alum water (3 or 4 oz. to the pint), or with a solution of white size, observing to dry it carefully after each coat. This tends to give lustre and beauty to the colours. The colours for this purpose should also be thickened with a little gum water. Before varnishing maps after colouring them, 2 or 3 coats of clean size should be applied with a soft brush——the first one to the back.

=MARASCHI′NO= (-kēno). _Syn._ MARASQUIN, Fr. A delicate liqueur spirit distilled from a peculiar cherry growing in Dalmatia, and afterwards sweetened with sugar. The best is from Zara, and is obtained from the marasca cherry only. An inferior quality is distilled from a mixture of cherries and the juice of liquorice root.

=MAR′BLE.= _Syn._ LIMESTONE, HARD CARBONATE OF LIME; MARMOR, CALCIS CARBONAS DURUS, M. ALBUM (B. P., Ph. E. & D.), L. Marbles are merely purer and more compact varieties of limestone, which admit of being sawn into slabs, and are susceptible of a fine polish. White marble is employed for the preparation of carbonic acid and some of the salts of lime. It contains about 65% of lime. Sp. gr. 2·70 to 2·85. The tests of its purity are the same as those already noticed under CHALK.

Marble is best cleaned with a little soap-and-water, to which some ox-gall may be added. Acids should be avoided. Oil and grease may be generally removed by spreading a paste made of soft soap, caustic potash lye, and fullers earth over the part, and allowing it to remain there for a few days; after which it must be washed off with clean water. Or, equal parts of American potash (crude carbonate of potash) and whiting are made into a moderately stiff paste with a sufficiency of boiling water, and applied to the marble with a brush. At the end of two or three days the paste is removed and the marble washed with soap-and-water. Any defect of polish may be brought up with tripoli, followed by putty powder, both being used along with water.

Marble is mended with one or other of the compounds noticed under CEMENTS.

Marble may be stained or dyed of various colours by applying coloured solutions or tincture to the stone, made sufficiently hot to make the liquid just simmer on the surface. The following are the substances usually employed for this purpose:——

BLUE. Tincture or solution of litmus, or an alkaline solution of indigo.

BROWN. Tincture of logwood.

CRIMSON. A solution of alkanet root in oil of turpentine.

FLESH COLOUR. Wax tinged with alkanet root, and applied to the marble hot enough to melt it freely.

GOLD COLOUR. A mixture of equal parts of white vitriol, sal ammoniac, and verdigris, each in fine powder, and carefully applied.

GREEN. An alkaline solution or tincture of sap green, or wax strongly coloured with verdigris; or the stone is first stained blue, and then the materials for yellow stain are applied.

RED. Tincture of dragon’s blood, alkanet root, or cochineal.

YELLOW. Tincture of gamboge, turmeric, or saffron; or wax coloured with annotta. Success in the application of these colours requires considerable experience. By their skilful use, however, a very pleasing effect, both of colour and grain, may be produced.

=MARBLING (of Books, &c.).= The edges and covers of books are ‘marbled’ by laying the colour on them with a brush, or by means of a wooden trough containing mucilage, as follows:——Provide a wooden trough, 2 inches deep, 6 inches wide, and the length of a super-royal sheet; boil in a brass or copper pan any quantity of linseed and water until a thick mucilage is formed; strain this into the trough, and let it cool; then grind on a marble slab any of the following colours in table beer. For——blue, Prussian blue or indigo;——red, rose-pink, vermilion, or drop lake;——yellow, king’s yellow, yellow ochre, &c.;——white, flake white;——black, ivory black, or burnt lampblack;——brown umber, burnt u., terra di sienna, burnt s.; black mixed with yellow or red also makes brown;——green, blue and yellow mixed;——purple, red and blue mixed. For each colour provide two cups——one for the ground colours, the other to mix them with the ox-gall, which must be used to thin them at discretion. If too much gall is used the colours spread; when they keep their place on the surface of the trough, on being moved with a quill, they are fit for use. All things being in readiness, the prepared colours are successively sprinkled on the surface of the mucilage in the trough with a brush, and are waved or drawn about with a quill or a stick according to taste. When the design is thus formed, the book, tied tightly between cutting boards of the same size, is lightly pressed with its edge on the surface of the liquid pattern, and then withdrawn and dried. The covers may be marbled in the same way, only the liquid colours must be allowed to run over them. The film of colour in the trough may be as thin as possible; and if any remains after the marbling, it may be taken off by applying paper to it before you prepare for marbling again. This process has been called FRENCH MARBLING.

To diversify the effect, a little sweet oil is often mixed with the colours before sprinkling them on, by which means a light halo or circle appears round each spot. In like manner spirit of turpentine, sprinkled on the surface of the trough, produces white spots. By staining the covers with any of the liquid dyes, and then dropping on them, or running over them, drops of the ordinary liquid mordants, a very pleasing effect may be produced. Vinegar black, or a solution of green copperas, thus applied to common leather, produces black spots or streaks, and gives a similar effect with most of the light dyes. A solution of alum or of tin in like manner produces bright spots or streaks, and soda or potash water dark ones. This style has been called EGYPTIAN MARBLE.——SOAP MARBLING is done by throwing on the colours, ground with a little white soap to a proper consistence, by means of a brush. It is much used for book-edges, stationery, sheets of paper, ladies’ fancy work, &c.——THREAD MARBLE is given by first covering the edge uniformly of one colour, then laying pieces of thick thread irregularly on different parts of it, and giving it a fine dark sprinkle. When well managed the effect is very pleasing.——RICE MARBLE is given in a similar way to the last by using rice.——TREE MARBLE is done on leather book-covers, &c., by bending the board a little in the centre, and running the marbling liquid over it in the form of vegetation. The knots are given by rubbing the end of a candle on those parts of the cover.——WAX MARBLE is given in a similar way to thread marble, but using melted wax, which is removed after the book is sprinkled and dried; or a sponge charged with blue, green, or red may be passed over. This, also, is much used for stationery work, especially for folios and quartos. The ‘vinegar black’ of the bookbinders is merely a solution of acetate of iron, made by steeping a few rusty nails or some iron filings in vinegar. All the ordinary liquid colours that do not contain strong acids or alkalies may be used, either alone or thickened with a little gum, for marbling or sprinkling books.

SPRINKLING is performed by simply dipping a stiff-haired painter’s brush into the colour, and suddenly striking it against a small stick held in the left hand over the work. By this means the colour is evenly scattered without producing ‘blurs’ or ‘blots.’

PAPER, PASTEBOARD, &c., in sheets, are marbled and sprinkled in a similar manner to that above described, but in this case the gum trough must, of course, be longer.

=MARGAR′IC ACID.= This term was formerly applied to a mixture of palmitic and stearic acids, produced by decomposing the alkaline soaps of solid fats with an acid, but it is now given to a fatty acid which can only be obtained artificially.

=MAR′GARIN.= _Syn._ MARGARATE OF GLYCERYL. A constituent formerly supposed to exist in solid fats, but now regarded as a mixture of stearin and palmitin.

=MARINE′ ACID.= See HYDROCHLORIC ACID.

=MARL.= A natural mixture of clay and chalk, with sand. It is characterised by effervescing with acids. According to the predominance of one or other of its component parts, it is called argillaceous, calcareous, or sandy marl. It is very generally employed as a manure for sandy soils, more particularly in Norfolk. See SOILS.

=MAR′MALADE.= Originally a conserve made of quinces and sugar; now commonly applied to the conserves of other fruit, more especially to those of oranges and lemons.

_Prep._ Marmalades are made either by pounding the pulped fruit in a mortar with an equal or a rather larger quantity of powdered white sugar, or by mixing them together by heat, passing them through a hair sieve whilst hot, and then putting them into pots or glasses. The fruit-pulps are obtained by rubbing the fruit through a fine hair sieve, either at once or after it has been softened by simmering it for a short time along with a little water. When heat is employed in mixing the ingredients, the evaporation should be continued until the marmalade ‘jellies’ on cooling. See CONSERVES, CONFECTIONS, ELECTUARIES, JAMS, JELLIES, and _below_.

=Marmalade, Apricot.= From equal parts of pulp and sugar.

=Marmalade, Mixed.= From plums, pears, and apples, variously flavoured to palate.

=Marmalade, Orange.= _Prep._ 1. From oranges (either Seville or St Michael’s, or a mixture of the two), by boiling the peels in syrup until soft, then pulping them through a sieve, adding as much white sugar, and boiling them with the former syrup and the juice of the fruit to a proper consistence.

2. By melting the confection of orange peel (Ph. L.), either with or without the addition of some orange or lemon juice, and then passing it through a sieve.

3. (CANDIED ORANGE MARMALADE.) From candied orange peel, boiled in an equal weight each of sugar and water, and then passed through a sieve.

4. (SCOTCH MARMALADE.)——_a._ Seville orange juice, 1 quart; yellow peel of the fruit, grated; honey, 2 lbs.; boil to a proper consistence.

_b._ Seville oranges, 8 lbs.; peel them as thinly as possible, then squeeze out the juice, boil it on the yellow peels for 1/4 of an hour, strain, add white sugar, 7 lbs., and boil to a proper consistence.

=Marmalade, Quince.= _Syn._ DIACYDONIUM. From quince flesh or pulp and sugar, equal parts; or from the juice (miva cydoniorum, gelatina c.), by boiling it to half, adding an equal quantity of white wine and 2/3rds of its weight of sugar, and gently evaporating the mixture.

=Marmalade, Tomato.= Like APRICOT MARMALADE, adding a few slices of onion and a little parsley.

=MARMORA′TUM.= Finely powdered marble and quicklime, well beaten together; used as a cement or mortar.

=MAR′ROW (Beef).= This is extensively employed by the perfumers in the preparation of various pomades and other cosmetics, on account of its furnishing an exceedingly bland fat, which is not so much disposed to rancidity as the other fats. It is prepared for use by soaking and working it for some time in lukewarm water, and afterwards melting it in a water bath, and straining it through a piece of muslin whilst hot. When scented it is esteemed equal to bear’s grease for promoting the growth of the hair.

=MARSH GAS.= Light carbonetted hydrogen.

=MARSH’S TEST.= See ARSENIOUS ACID.

=MARSHMALLOW.= _Syn._ ALTHÆA (Ph. L. & E.), L. The root (leaves and root——Ph. E.) of _Althæa officinalis_, Linn., or common marshmallow. (Ph. L.) It is emollient and demulcent; the decoction is useful in irritation of the respiratory and urinary organs, and of the alimentary canal. The flowers as well as the root are reputed pectoral.

=MARTIN’S POWDER.= A mixture of white arsenic and the powdered stems of _Orobanche virginiana_ (Linn.), a plant common in Virginia. An American quack remedy for cancer.

=MASS.= _Syn._ MASSA, L. This term is commonly applied in pharmacy and veterinary medicine to certain preparations which are not made up into their ultimate form. Thus, we have ‘ball-masses,’ ‘pill-masses,’ &c.; of which, for convenience, large quantities are prepared at a time, and are kept in pots or jars, ready to be divided into balls or pills, as the demands of business may require. (See _below_.)

=MASSES (Veterinary).=[24]

[Footnote 24: Reprinted from Tuson’s ‘Veterinary Pharmacopœia.’]

=Massa Aloes.= MASS OF ALOES. _Syn._ CATHARTIC MASS. _Prep._ Take of Barbadoes aloes, in small pieces, 8 parts; glycerin, 2 parts; ginger, in powder, 1 part; melt together in a water bath, and thoroughly incorporate by frequent stirring.——_Use._ Cathartic for the horse.——_Dose._ From 6 to 8 dr.

=Massa Aloes Composita.= COMPOUND MASS OF ALOES. _Syn._ ALTERATIVE MASS. _Prep._ Take of Barbadoes aloes, in powder, 1 oz.; soft soap, 1 oz.; common mass, 6 oz.; thoroughly incorporate by beating in a mortar, so as to form a mass.——_Use._ Alterative for the horse.——_Dose_, 1 oz.

=Massa Antimonii Tartarata Composita.= COMPOUND MASS OF TARTARATED ANTIMONY. _Syn._ FEVER BALL. _Prep._ Take of tartrated antimony, in powder, 1/2 dr.; camphor, in powder, 1/2 dr.; nitrate of potash, in powder, 2 dr.; common mass, a sufficiency; mix so as to form a bolus.——_Use._ Febrifuge for the horse.——_Dose._ The above mixture constitutes 1 dose.

=Massa Belladonnæ Composita.= COMPOUND MASS OF BELLADONNA. _Syn._ COUGH BALL. _Prep._ Take of extract of belladonna, 1/2 to 1 dr.; Barbadoes aloes, in powder, 1 dr.; nitrate of potash, in powder, 2 dr.; common mass, a sufficiency; mix so as to form a bolus.——_Use._ For the horse in chronic cough.——_Dose._ The above mixture constitutes 1 dose.

=Massa Cathechu Composita.= COMPOUND MASS OF CATECHU. _Syn._ ASTRINGENT MASS. _Prep._ Take of extract of catechu, in fine powder, 1 oz.; cinnamon bark, in fine powder, 1 oz.; common mass, 6 oz.; mix.——_Use._ Astringent for the horse.——_Dose_, 1 oz., in the form of a bolus.

=Massa Communis.= COMMON MASS. _Prep._ Take of linseed, finely ground, and treacle, of each equal parts; mix together so as to form a mass.——_Use._ An excipient for medicinal agents when they are to be administered in the form of bolus.

=Massa Cupri Sulphatis.= MASS OF SULPHATE OF COPPER. _Syn._ TONIC MASS. _Prep._ Take of sulphate of copper, finely powdered, 1 oz.; ginger, in powder, 1 oz.; common mass, 6 oz.; mix.——_Use._ Tonic for the horse.——_Dose_, 6 to 8 dr.

=Massa Digitalis Composita.= COMPOUND MASS OF DIGITALIS. _Syn._ COUGH BALL. _Prep._ Take of Barbadoes aloes, in powder, 2 oz.; digitalis, 1 oz.; common mass, 13 oz.; mix.——_Use._ For the horse in chronic cough.——_Dose_, 1 oz. once or twice a day.

=Massa Ferri Sulphatis.= MASS OF SULPHATE OF IRON. _Syn._ TONIC MASS. _Prep._ Take of sulphate of iron, in powder, 2 oz.; ginger, in powder, 1 oz.; common mass, 5 oz.; mix.——_Use._ Tonic for the horse.——_Dose_, 6 to 8 dr.

=Massa Resinæ Composita.= COMPOUND MASS OF RESIN. _Syn._ DIURETIC MASS. _Prep._ Take of resin, in powder, nitrate of potash, in powder, hard soap, of each equal parts; mix.——_Use._ Diuretic for the horse.——_Dose_, 1 oz.

=Massa Zingiberis Composita.= COMPOUND MASS OF GINGER. _Syn._ CORDIAL MASS. _Prep._ Take of ginger, in powder, gentian root, in powder, treacle, of each equal parts, a sufficiency; mix so as to form a mass.——_Use._ Stomachic for the horse.——_Dose_, 1 oz.

=MAS′SICOT.= _Syn._ MASTICOT, YELLOW PROTOXIDE OF LEAD; PLUMBI OXYDUM FLAVUM, CERUSSA CITRINA, L. The dross that forms on melted lead exposed to a current of air, roasted until it acquires a uniform yellow colour. Artists often apply the same name to white lead roasted until it turns yellow. Used as a pigment.

=MAS′TIC.= _Syn._ MASTICH, GUM MASTIC; MASTICHE, L. The “resin flowing from the incised bark of _Pistacia Lentiscus_, var. _Chia_.” (Ph. L.) It occurs in pale yellowish, transparent, rounded tears, which soften between the teeth when chewed, and giving out a bitter, aromatic taste. Sp. gr. 1·07. It is soluble in both rectified spirit and oil of turpentine, forming varnishes. It is chiefly used as a ‘masticatory,’ to strengthen and preserve the teeth, and perfume the breath.

=Mastic.= Fine mortar or cement used for plastering walls, in which the ingredients, in a pulverulent state, are mixed up, either entirely or with a considerable portion of linseed oil. It sets very hard, and is ready to receive paint in a few days. See CEMENTS.

=MASTICA′TION.= The act of chewing food, by which it not only becomes comminuted, but mixed with the saliva, and reduced to a form fit for swallowing. It has been justly regarded by the highest authorities as the first process of digestion, and one without which the powers of the stomach are overtasked, and often performed with difficulty. Hence the prevalence of dyspepsia and bowel complaints among persons with bad teeth, or who ‘bolt’ their food without chewing it.

=MAS′TICATORIES.= _Syn._ MASTICATORIA, L. Substances taken by chewing them. They are employed as intoxicants, cosmetics, and medicinals; generally with the first intention. The principal masticatory used in this country is tobacco. In Turkey, and several other Eastern nations, opium is taken in a similar manner. In India, a mixture of areca nut, betel leaf, and lime, performs the same duties; whilst in some other parts of the world preparations of the cacao are employed. As cosmetics, orris root, cassia, cinnamon, and sandal wood are frequently chewed to scent the breath. Among medicinals, mastic and myrrh are frequently chewed to strengthen the teeth and gums; pellitory, to relieve the toothache; and rhubarb, ginger, and gentian, to relieve dyspepsia and promote the appetite.

_Prep._ 1. (Augustin.) Mastic, pellitory (both in powder), and white wax, of each 1 dr.; mixed by heat and divided into 6 balls. In toothache, loose teeth, &c.

2. (W. Cooley.) Mastic, myrrh, and white wax, of each 1 part; rhubarb, ginger, and extract of gentian, of each 2 parts; beaten up with tincture of tolu, q. s., and divided into boluses or lozenges of 10 gr. each. One or two to be chewed an hour before dinner; in dyspepsia, defective appetite, &c.

3. (Quincy.) Mastic, 3 oz.; pellitory and stavesacre seed, of each 2 dr.; cubebs and nutmegs, of each 1 dr.; angelica root, 1/2 dr.; melted wax, q. s. to make it into small balls. As a stimulant to the gums, and in toothache.

4. Opium, ginger, rhubarb, mastic, pellitory of Spain, and orris root, of each 1 dr.; melted spermaceti, q. s. to mix; for 6-gr. pills. As the last, and in toothache and painful gums.

=MAS′TICOT.= See MASSICOT.

=MATCHES (Cooper’s).= _Syn._ SWEETENING MATCHES. These are made by dipping strips of coarse linen or canvas into melted brimstone. For use, the brimstone on one of them is set on fire, and the match is then at once suspended in the cask, and the bung loosely set in its place. After the lapse of 2 or 3 hours the match is removed and the cask filled with liquor. Some persons pour a gallon or two of the liquor into the cask before ‘matching’ it. The object is to allay excessive fermentation. The operation is commonly adopted in the Western Counties for cider intended for shipment, or other long exposure during transport. It is also occasionally employed for inferior and ‘doctored’ wines.

=MATCHES (Instantaneous Light).= Of these there are several varieties, of which the one best known, and most extensively used, is the common phosphorus match, known as the ‘congreve’ or ‘lucifer.’[25] We need not describe the ‘chemical matches,’ ‘phosphorus bottles,’ and ‘prometheans,’ in use during the early part of the present century, as these are quite obsolete. We will simply sketch the general process of manufacture now in use for phosphorus matches:

[Footnote 25: The original ‘LUCIFERS,’ or ‘LIGHT-BEARING MATCHES,’ invented in 1826, consisted of strips of pasteboard, or flat splints of wood, tipped first with sulphur, and then with a mixture of sulphide of antimony and chlorate of potassa, and were ignited by drawing them briskly through folded glass-paper. They required a considerable effort to ignite them, and the composition was apt to be torn off by the violence of the friction. The term ‘lucifer’ having become familiar, was applied to the simpler and more effective match afterwards introduced under the names of ‘CONGREVE’ and ‘CONGREVE LIGHT,’]

_Manuf._ The wooden splints are cut by steam machinery from the very best quality of pine planks, perfectly dried at a temperature of 400° Fahr. English splints are of two sizes——‘large’ and ‘minnikins,’ the former 2-1/4 inches longer, and the latter somewhat shorter. In the manufacture double-lengths are used, so that each splint may be coated with the igniting composition at both ends, and then cut asunder in the middle to form two matches. In England the splints are usually cut square in form, but in Germany they are cylindrical, being prepared by forcing the wood through circular holes in a steel plate. The ends of the double splints having been slightly charred by contact with a red-hot plate, are coated with sulphur by dipping them to the requisite depth in the melted material. In some cases the ends are saturated with melted wax or paraffin instead of sulphur. The splints are then arranged in a frame between grooved boards in such a manner that the prepared ends project on each side of the frame. These projecting ends are then tipped with the phosphorus composition, which is spread to a uniform depth of about 1/8 inch on a smooth slab of stone, kept warm by means of steam beneath. When partially dry, the tipped splints are taken from the frames, cut through the middle, and placed in heaps of 100, ready for ‘boxing.’

The different compositions for tipping the matches in use in different countries and factories all consist essentially of emulsions of phosphorus in a solution of glue or gum, with or without other matters for increasing the combustibility, for colouring, &c. In England the composition contains a considerable quantity of chlorate of potassa, which imparts a snapping and flaming quality to the matches tipped with it, and but little phosphorus, on account of the moisture of the climate. In Germany the proportion of phosphorus used is much larger, and nitre, or some metallic peroxide, replaces chlorate of potassa. The German matches light quietly with a mild lambent flame, and are injured quickly by damp. The following formulæ have been selected:

1. (ENGLISH.) Fine glue, 2 parts, broken into small pieces, and soaked in water till quite soft, is added to water, 4 parts, and heated by means of a water bath until it is quite fluid, and at a temperature of 200° to 212° Fahr. The vessel is then removed from the fire, and phosphorus, 1-1/2 to 2 parts, is gradually added, the mixture being agitated briskly and continually with a ‘stirrer’ having wooden pegs or bristles projecting at its lower end. When a uniform emulsion is obtained, chlorate of potassa, 4 to 5 parts, powdered glass, 3 to 4 parts, and red lead, smalt, or other colouring matter, a sufficient quantity (all in a state of very fine powder) are added, one at a time, to prevent accidents, and the stirring continued until the mixture is comparatively cool.

According to Mr G. Gore, the above proportions are those of the best quality of English composition. The matches tipped with it deflagrate with a snapping noise. (See _above_.)

2. (GERMAN.)——_a._ (Böttger.) Dissolve gum Arabic, 16 parts, in the least possible quantity of water, add of phosphorus (in powder), 9 parts, and mix by trituration; then add of nitre, 14 parts; vermillion or binoxide of manganese, 16 parts, and form the whole into a paste, as directed above; into this the matches are to be dipped, and then exposed to dry. As soon as the matches are quite dry they are to be dipped into very dilute copal varnish or lac varnish, and again exposed to dry, by which means they are rendered waterproof, or at least less likely to suffer from exposure in damp weather.

_b._ (Böttger.) Glue, 6 parts, is soaked in a little cold water for 24 hours, after which it is liquefied by trituration in a heated mortar; phosphorus, 4 parts, is now added, and rubbed down at a heat not exceeding 150° Fahr.; nitre (in fine powder), 10 parts, is next mixed in, and afterwards red ochre, 5 parts, and smalt, 2 parts, are further added, and the whole formed into a uniform paste, into which the matches are dipped, as before. Cheaper than the last.

_c._ (Diesel.) Phosphorus, 17 parts; glue, 21 parts; red lead, 24 parts; nitre, 38 parts. Proceed as above.

_Obs._ Matches tipped with the above (_a_, _b_, and _c_) inflame without fulmination when rubbed against a rough surface, and are hence termed ‘noiseless matches’ by the makers.

3. (SAFETY MATCHES.) The latest improvement of note in the manufacture of matches is that of Landstrom, of Jonkoping, in Sweden, adopted by Messrs Bryant and May (Patent). It consists in dividing the ingredient of the match-mixture into two separate compositions, one being placed on the ends of the splints, as usual, and the other, which contains the phosphorus, being spread in a thin layer upon the end or lid of the box. The following are the compositions used by the patentee:——_a._ (For the splints.) Chlorate of potassa, 6 parts; sulphuret of antimony, 2 to 3 parts; glue, 1 part.——_b._ (For the friction surface.) Amorphous phosphorus, 10 parts; sulphuret of antimony or peroxide of manganese, 8 parts; glue, 3 to 6 parts; spread thinly upon the surface, which has been previously made rough by a coating of glue and sand.

By thus dividing the composition the danger of fire arising from ignition of the matches by accidental friction is avoided, as neither the portion on the splint nor that on the box can be ignited by rubbing against an unprepared surface. Again, by using the innocuous red or amorphous phosphorus, the danger of poisoning is entirely prevented.

=MATÉ.= _Syn._ PARAGUAY TEA. This is the dried leaf of a small shrub, the _Ilex Paraguayenses_, or Brazilian holly, growing in Paraguay and Brazil; by the inhabitants of which places, as well as South America generally, it is largely employed in the form of a beverage as tea. Its active ingredient, _Paraguaine_, formerly supposed to be a distinct principle, has from further researches into its composition been discovered to be identical with theine and caffeine——the alkaloids of tea and coffee.

Mr Wanklyn ascribes the following composition to maté:——

Moisture 6·72 Ash 5·86 Soluble organic matter 25·10 Insoluble organic matter 62·32 —————— 100·00

=MATE′′RIA MED′ICA.= A collective name of the various substances, natural and artificial, employed as medicines or in the cure of disease. In its more extended sense it includes the science which treats of their sources, properties, classification, and applications. The _materia medica of the Pharmacopœia_ is a mere list, with occasional notes, “embracing the animal, vegetable, and chemical substances, whether existing naturally, prepared in officinal chemical preparations, or sold in wholesale trade, which we (the College) direct to be used either in curing diseases or in preparing medicines.” (Ph. L.)

=MAT′ICO.= _Syn._ SOLDIER’S HERB; MATECO (B. P., Ph. D.); MATICA, HERBA MATICÆ, L. The dried leaves of a Peruvian plant, generally believed to be the _Artanthe elongata_, one of the _Piperaceæ_. The leaves have been employed with considerable success as a mechanical external styptic; applied to leech-bites, slight cuts, and other wounds, &c., and pressed on with the fingers, they seldom fail to arrest the bleeding. Matico has also been much lauded as an internal astringent and styptic, in hæmorrhages from the lungs, stomach, bowels, uterus, &c.; but as it is nearly destitute of astringent properties, its virtues in these cases must have been inferred from its external action. As an aromatic, bitter stimulant, closely resembling the peppers, it has been proposed as a substitute for cubebs and black pepper, in the treatment of diseases of the mucous membranes, piles, &c.——_Dose_, 1/2 to 2 dr.; in powder; or under the form of infusion, tincture, or boluses.

=MATURA′TION.= Growing ripe. Amongst surgeons this term is applied to the process of suppuration, or that which succeeds inflammation, and by which pus or matter is collected in an abscess. Warmth, irritation, and a liberal diet promote this change; cold, sedatives, and depletion, retard it. The maturation of fermented liquor is noticed under BREWING, MALT LIQUORS, WINES, &c.

=MEAD.= _Syn._ MELLINA, L. An old English liquor, made from the combs from which the honey has been drained, by boiling them in water, and fermenting the saccharine solution thus obtained. It is commonly confounded with metheglin. Some persons add 1 oz. of hops to each gallon; and, after fermentation, a little brandy. It is then called sack mead, See METHEGLIN.

=MEAL.= The substance of edible grain ground to powder, without being bolted or sifted. Barley meal and oat meal are the common substances of this class in England. In North America the term is commonly applied to ground Indian corn, whether bolted or not. (Goodrich.) The four resolvent meals of old pharmacy (_quatuor farinæ resolventes_) are those of barley, beans, linseed, and rye.

=MEALS.= The “periods of taking food, usually adopted, in conformity with convenience and the recurrences of hunger, are those which are best adapted to the purposes of health; namely, the morning meal, the midday meal, and the evening meal.” “That these are the proper periods for meals is evident from the fact of their maintaining their place amid the changes which fashion is constantly introducing.” “If we look at these periods in another point of view, we shall find an interval of four hours left between them for the act of digestion and subsequent rest of the stomach. Digestion will claim between two and three hours of the interval; the remaining hour is all that the stomach gets of rest, enough, perhaps, but not too much, not to be justly infringed.” (Eras. Wilson.)

=MEA′SLES.= _Syn._ RUBEOLA, MORBILLI, L. This very common disease is characterised by feverishness, chilliness, shivering, head-pains, swelling and inflammation of the eyes, shedding of sharp tears, with painful sensibility to light, oppressive cough, difficulty of breathing, and sometimes vomiting or diarrhœa. These are followed about the fourth day by a crimson rash upon the skin, in irregular crescents or circles, and by small red points or spots, which are perceptible to the touch, and which, after four or five days, go off with desquamation of the cuticle. The fever, cough, &c., often continue for some time; and unless there have been some considerable evacuations, either by perspiration or vomiting, they frequently return with increased violence, and occasion great distress and danger.

_Treat._ When there are no urgent local symptoms, mild aperients, antimonial diaphoretics, and diluents, should be had recourse to; but when the inflammatory symptoms are emergent, and the lungs are weak, especially in plethoric habits, blood may be taken. The cough may be relieved by expectorants, demulcents, and small doses of opium; and the diarrhœa by the administration of the compound powder of chalk and opium; the looseness of the bowels, however, had better not be interfered with, unless it be extreme.

Measles are most prevalent in the middle of winter, and though common to individuals of all ages, are most frequent amongst children. The plethoric, and those of a scrofulous habit, or one which has a syphilitic taint, suffer most from them.

Like the smallpox, the measles are contagious, and seldom attack the same person more than once during life. See RASH.

=MEASURE.= _Syn._ MENSURA, L. The unit or standard by which we estimate extension, whether of length, superficies, or volume. The following tables represent the values and proportions of the principal measures employed in commerce and the arts:——

TABLE I. _English Lineal Measures._

+---------+----------+----------+-----------+------------+--------------+ | Inches. | Feet. | Yards. | Poles. | Furlongs. | Miles. | +---------+----------+----------+-----------+------------+--------------+ | 1· | ·083 | ·028 | ·00505 | ·00012626 | ·0000157828 | | 12· | 1· | ·333 | ·06060 | ·00151515 | ·00018939 | | 36· | 3· | 1· | ·1818 | ·004545 | ·00056818 | | 198· | 16·5 | 5·5 | 1· | ·025 | ·003125 | | 7920· | 660· | 220· | 40· | 1· | ·125 | | 63360· | 5280· | 1760· | 320· | 8· | 1· | +---------+----------+----------+-----------+------------+--------------+

⁂ The unit of the above table is the yard, of which no legal standard has existed since that established by the statute of 1824 was destroyed by the fire which consumed the two Houses of Parliament in 1834.

TABLE II. _English Measures of Superficies._

+----------+-----------+--------------+-------------+-------------+ | Square | Square | Poles. | Roods. | Acres. | | Feet. | Yards. | | | | +----------+-----------+--------------+-------------+-------------+ | | | | | | | 1· | ·1111 | ·00367309 | ·000091827 | ·000022957 | | 9· | 1· | ·0330579 | ·000826448 | ·000206612 | | 272·25 | 30·25 | 1· | ·025 | ·00625 | | 10890· | 1210· | 40· | 1· | ·25 | | 43560· | 4840· | 160· | 4· | 1· | +----------+-----------+--------------+-------------+-------------+

TABLE III. _English Measure of Volume.——The_ IMPERIAL STANDARD, _and the relative value of its divisions, including those used in Medicine, with their_ EQUIVALENTS _in avoirdupois and troy weight._

+------+-------------+------------+-------------+------------+-----------+-------+--------+-----------+-----------------------+ |[minims] fʒ | f℥ | O. | Oij. | C. | | | | | |Minims| | | | | | | | | Equivalents in | | or | Fluid | Fluid | | | | | | | _distilled water_, at | |drops.| Drachms. | Ounces. | Pints. | Quarts. | Gallons. | Pecks.|Bushels.| Quarters. | 62° Fahr., in | +------+-------------+------------+-------------+------------+-----------+-------+--------+-----------+/---------/\----------\| | | | | | | | | | | Troy | Avoird. | | | | | | | | | | | grains. | weight. | | | | | | | | | | +-----------+-----------+ | 1·| ·01666666| ·00208333| ·00010416| ·00005208| ·00001302| —— | —— | —— | ·91146| | | 60·| 1· | ·125 | ·00625 | ·003125 | ·00078125| —— | —— | —— | 54·6875 |_lb._ _oz._| | 480·| 8· | 1· | ·05 | ·025 | ·00625 | —— | —— | —— | 437·5 | 1 | | 9600·| 160· | 20· | 1· | ·5 | ·125 | ·0625| ·015625| ·001953125| 8750· | 1 4 | |19200·| 320· | 40· | 2· | 1· | ·25 | ·125 | ·03125 | ·00390625 |17500· | 2 8 | |76800·|1280· | 160· | 8· | 4· | 1· | ·5 | ·125 | ·015625 |70000· | 10 | | |2560· | 320· | 16· | 8· | 2· | 1· | ·25 | ·03125 | —— | 20 | | | |1280· | 64· | 32· | 8· | 4· |1· | ·125 | —— | 80 | | | | | 512· |256· |64· |32· |8· |1· | —— | 640 | +------+-------------+------------+-------------+------------+-----------+-------+--------+-----------+-----------+-----------+

⁂ The standard unit of the above table is the gallon, which is declared, by statute, to be capable of “containing ten pounds avoirdupois weight of distilled water, weighed in the air at the temperature of 62° Fahr., the barometer being at 30 inches.” The pound avoirdupois contains 7000 grains, and it is declared that a cubic inch of distilled water, under the above conditions, weighs 252·458 grains; hence the capacity of the imperial gallon and its divisions are as follows:——

Imperial gallon = 277·274 cubic inches. ” quart = 69·3185 ” ” pint = 34·65925 ” Fluid ounce = 1·73296 ” ” drachm = ·21662 ”

‡‡‡ The imperial gallon is 1-5th larger than the old wine gallon,——1-60th smaller than the old beer gallon, and——1-32nd larger than the old dry-measure gallon.

TABLE IV. _French Metrical or Decimal Measures of Length._

+----------+---------+------------------------------------------------+ | | | Equivalents in | | | |/---------------------/\-----------------------\| | Names. | Eq. in |English Inches,| English Long Measure, | | | Mètres. |at 32° Fahr. | at 62° Fahr. | +----------+---------+---------------+--------------------------------+ | | | |Miles. Fur. Yds. Feet. Inch.| |Millimètre| ·001| ·03937 | | |Centimètre| ·01 | ·39371 | | |Décimètre | ·1 | 3·93708 | | |Mètre | 1· | 39·37079 | 1 0 3·37 | |Decamètre | 10· | 393·70790 | 10 2 9·7 | |Hectomètre| 100· | 3937·07900 | 109 1 1·078| |Kilomètre | 1000· | 39370·79000 | 4 213 1 10·3 | |Myriamètre|10000· | 393707·90000 | 6 1 156 0 9·17 | +----------+---------+---------------+--------------------------------+

⁂ The standard unit of the above table is the mètre, which has been determined to be 39·37079 inches, at 32° Fahr. (Capt. Kater); the English foot is taken at 62° Fahr. The true length of the mètre, reduced to the latter temperature, is 39·370091 English inches; a number which varies from that in the table only at the fourth decimal figure. It will be perceived that the principle of nomenclature adopted in applying the names, was to prefix the Greek numerals to the decimal multiples, and the Latin numerals to the decimal subdivisions.

TABLE V. _French Metrical or Decimal Measures of Volume._

+----------+---------+---------+--------------------------------------+ | Names. | Eq. in | Eq. in | | | | Litres. |English | Equivalent in English Measures. | | | | Cubic | | | | | Inches | | +----------+---------+---------+--------------------------------------+ | | | |_Gall._ _Pints._ _Oz._ _Dr._ _Minims._| |Millilitre| ·001| ·0610| 16·9 | |Centilitre| ·01 | ·6103| 2 49· | |Decilitre | ·1 | 6·1028| 3 4 10·36 | |Litre | 1· | 61·028 | 1 15 1 43·69 | |Decalitre | 10· | 610·28 | 2 1 12 1 16·9 | |Hectolitre| 100· |6102·8 | 22 0 1 4 49· | |Kilolitre | 1000· |61028· | 220 0 16 6 40· | |Myrialitre|10000· |610280· |2201 (=275-1/8 _bushels_). | +----------+---------+---------+--------------------------------------+

⁂ The standard unit in the above table is the litre, or the cube of the 1/10 of a mètre. The French centiare contains 1 square mètre,——the are, 100 do.,——the hectare, 10,000 do. The old Paris pint is equal to 1·678 English imperial pint.

‡‡‡ The capacity of solids and aëriform fluids is taken in cubic inches, or feet, in England. In France, the stere, or mètre cube, equal to 35·31658 English cubic feet, is the standard unit.

TABLE VI. _Miscellaneous Measures and their Equivalents:_

Tea or coffee spoonful (average) = 1 fl. dr. Dessert spoonful ” = 2 ” Table spoonful ” = 4 ” Wine-glassful ” = 2 fl. oz. Tea-cupful ” = 5 ” Breakfast-cupful ” = 8 ” Tumblerful ” = 8 ” Basinful ” = 12 ” Thimbleful ” = 3/4 fl. dr. Pinch (of leaves and flowers) ” = 1 dr. Handful (of leaves and flowers) ” = 10 ” Cubic inch of water, at 62° Fahr. = 252·458 gr. Cubic foot of water, at 62° Fahr. = 62·32106 lb. ———— Line = 1/12 inch. Barleycorn = 1/3 ” Hand = 4 ” Chain = 4 poles or 22 yards.

=MEAT.= The muscular tissue or flesh of the principal animals constituting the food of man may be said to be composed of the same proximate principles, and, given an equal digestibility and power of being assimilated, may be also said to have an equally nutritive value.

Since meat, however, is generally eaten with a certain amount of fat, which accompanies it in varying quantity, the capacity of the meat for forming muscle will, of course, be in inverse proportion to the amount of fat it contains; on the contrary, its power of raising the bodily temperature will be in direct proportion. Moleschott (quoted by Parkes) gives the following as the mean composition of fresh beef, as determined by all the Continental chemists:——

Water 73·4 Soluble albumen and hæmatin 2·25 Insoluble albuminous substances 15·20 Gelatinous substances 3·30 Fat 2·87 Extractive matter 1·38 Creatin 0·068 Ash 1·6

Dr Parkes remarks of the amount of fat given in the above analysis “that it is evidently too low.”

In the above table we recognise in the albuminous and gelatinous substances the source of the muscular tissue of the human organism. The ash contains the chlorides, carbonates, and phosphates of potassium, sodium, and calcium. From these salts are derived the hydrochloric acid of the gastric juice, the sodium of the bile, and the calcium phosphate and carbonate of the skeleton. Iron is also present, and this finds its way into the blood.

The flavour of meat is much influenced by the food of the animal. The flesh of the Pampas pig is found to be rank and disagreeable when the animal is killed in its wild state; if, however, the food be changed for the better, the flesh becomes altogether different and quite eatable. The pork of pigs fed on flesh is said to give off a strong odour, the fat at the same time being unusually soft. Soft fat is also said to form in animals that have been fed on oily foods.

When meat is roasted, the fire gradually coagulates the albumen of the joint, the coagulation commencing at the surface, and spreading by degrees to the interior. Unless the roasting be continued long enough, sufficient heat will not reach the parts nearest the centre to effect their coagulation; and if under these circumstances the meat be removed from the fire, the uncoagulated or inner parts will present the well-known red and juicy appearance known as ‘underdone.’ Although a certain quantity of the gravy (which consists of the soluble and saline ingredients) escapes in the process, the greater part is retained. The brown agreeably sapid substance formed on the outside of the meat is known as _osmazome_, and which is concentrated gravy. The melting fat which collects below forms the dripping. The loss in the meat is principally water.

The chemical effects of boiling are explained under the article devoted to that subject.

Meat generally loses from 30 to 40 per cent., and sometimes as much as 60 per cent. in weight, by cooking.

The amount of bone varies, being seldom less than 8 per cent. It amounts in the neck and brisket to about 10 per cent. and from one third to sometimes half the total weight in shins and legs of beef.

The most economical parts are the round and thick flank, next to these the brisket and sticking-piece, and lastly, the leg.

In choosing mutton and pork, selection should be made of the leg, after this of the shoulder.[26]

[Footnote 26: Letheby.]

“Oxen,” says M. Bizet, “yield of _best quality_ beef 57 per cent. of meat, and 43 per cent. waste. The waste includes the internal viscera, &c. _Second quality_ of beef, 54 per cent. meat and 46 per cent. waste; _third quality_ beef, 51 per cent. meat and 49 per cent. waste. In milking-cows, 46 per cent. meat and 54 per cent. waste. Calves yield 60 per cent. meat, and 40 per cent. loss; and sheep yield 50 per cent. meat, and 50 per cent. loss.” Dr Parkes differs from Bizet as to the latter’s value of the meat of the calf. He says the flesh of young animals loses from 40 to 50 per cent. in cooking.

It seems to be agreed, however, that animals when slaughtered should be neither too young nor too old. The flesh of young animals, although more tender, is less digestible than that of older ones; it is also poorer in salts, fat, and an albuminous substance called _syntonin_.

=Consumption of Meat.= Dr Letheby, writing in 1868, says that in London “the indoor operatives eat it to the extent of 14·8 oz. per adult weekly; 70 per cent. of English farm labourers consume it, and to the extent of 16 oz. per man weekly; 60 per cent. of the Scotch, 30 of the Welsh, and 20 of the Irish also eat it. The Scotch probably have a larger allowance than the English, considering that braxy mutton[27] is the perquisite of the Scotch labourer; but the Welsh have only an average amount of 2-1/2 oz. per adult weekly; and the Irish allowance is still less. It is difficult to obtain accurate returns of the quantity of meat consumed in London; but if the computation of Dr Wynter is correct, it is not less than 30-3/4 oz. per head weekly, or about 4-1/2 oz. per day for every man, woman, and child. In Paris, according to M. Armand Husson, who has carefully collected the _octroi_ returns, “it is rather more than 49 oz. per head weekly, or just 7 oz. a day.” Bondin states that throughout France the consumption is about 50 grammes daily, or under 1-3/4 oz.

[Footnote 27: See further on.]

Dr Letheby, in his work ‘On Food,’ gives the following as the characteristics of good meat:——

“1st. It is neither of a pale pink colour nor of a deep purple tint, for the former is a sign of disease, and the latter indicates that the animal has not been slaughtered, but has died with the blood in it, or has suffered from acute fever.

“2nd. It has a marked appearance from the ramifications of little veins of fat among the muscles.

“3rd. It should be firm and elastic to the touch, and should scarcely moisten the fingers——bad meat being wet, and sodden and flabby, with the fat looking like jelly or wet parchment.

“4th. It should have little or no odour, and the odour should not be disagreeable, for diseased meat has a sickly cadaverous smell, and sometimes a smell of physic. This is very discoverable when the meat is chopped up and drenched with warm water.

“5th. It should not shrink or waste much in cooking.

“6th. It should not run to water, or become very wet on standing for a day or so, but should, on the contrary, dry upon the surface.

“7th. When dried at a temperature of 212° or thereabout, it should not lose more than from 70 to 74 per cent. of its weight, whereas bad meat will often lose as much as 80 per cent.

“Other properties of a more refined character will also serve for the recognition of bad meat, as that the juice of the flesh is alkaline or neutral to test-paper, instead of being distinctly acid, and the muscular fibre, when examined under the microscope is found to be sodden and ill-defined.”

_Unsound meat——diseased meat._ Dr Letheby, in his ‘Lectures on Food,’ published in 1868, states that the seizure and condemnation, in London, of meat unfit for human food, during a period extending over seven years, amounted to 700 tons per annum, or to about 1-750th of the whole quantity consumed. These 700 tons he dissects into lbs. as follows:——“805,653 lbs. were diseased, 568,375 lbs. were putrid, and 193,782 lbs. were from animals that had not been slaughtered, but had died from accident or disease. It consisted of 6640 sheep and lambs, 1025 calves, 2896 pigs, 9104 quarters of beef, and 21,976 joints of meat.”

He admits, however, that this amount, owing to the difficulties and inefficiency of the mode of supervision, bears a very insignificant proportion to the actual quantity which escaped detection, and which was, therefore, partaken of as food. Professor Gamgee says that one fifth of the meat eaten in the metropolis is diseased. In 1863 the bodies of an enormous number of animals suffering from _rinderpest_, as well as from _pleuro-pneumonia_, were consumed in London; and we know that thousands of sheep die every year, in the country, of _rot_; the inference from which latter fact is that, since the carcases are neither eaten there nor buried on the spot, they are sent up to, and thrown upon, the London markets. The worst specimens find their way to the poorer neighbourhoods, where, as might be expected, their low price ensures a ready sale for them. These sales, it is said, mostly take place at night.

The above statements, which, if we exclude Professor Gamgee’s figures, do not solve the problem as to the quantity of unsound meat consumed in London, not unreasonably justify the assumption that it is very considerable; and this being admitted, we should be prepared to learn that it was a fertile source of disease of a more or less dangerous character.

There is, however, such extensive divergence in the various data bearing upon this point, that no satisfactory solution of it can be said to be afforded. Thus, Livingstone states that, when in South Africa, he found that neither Englishmen nor natives could partake of the flesh of animals affected with _pleuro-pneumonia_ without its giving rise to malignant carbuncle, and sometimes, in the case of the natives, to death, and Dr Letheby attributes the increased number of carbuncles and phlegmons amongst our population to the importation from Holland of cattle suffering from the same disease. On the contrary, Dr Parkes says he was informed, on excellent authority, that the Caffres invariably consume the flesh of their cattle that die of the same epidemic, without the production of any ill effects. Again, there are numerous well-attested cases in which the flesh of sheep which have died from _braxy_ (a disease that makes great ravages amongst the flocks in Scotland) is constantly eaten without injurious results by the Scotch shepherd. The malady causes death in the sheep from the blood coagulating in the vital organs, and the sheep that so dies becomes the property of the shepherd, who, after removing the offal, is careful to cut out the dark congealed blood before cooking it.[28] Sometimes he salts down the carcase. In cases, however, where thorough cooking or an observance of the above precautions have been neglected, very dangerous and disastrous consequences have ensued. During the late siege of Paris large quantities of the flesh of horses with glanders appear to have been eaten with no evil consequences: and Mr Blyth, in his ‘Dictionary of Hygiène,’ quotes a similar case from Tardieu, who states that 300 army horses affected with glanders (_morve_) were led to St Germain, near Paris, and killed. For several days they served to feed the poor of the town without causing any injury to health.

[Footnote 28: Letheby.]

A similar exemption from any evil effect following the consumption of diseased flesh is recorded by Professor Brucke, of Vienna.

Not many years since the cattle of a locality in Bohemia, being attacked by _rinderpest_, were ordered by the Government to be slaughtered, after which they were buried. The poor people dug up the diseased carcases, cooked the meat, and ate it, with no injurious result.

Parent Duchâtelet cites a case where the flesh of seven cows attacked with rabies was eaten without injury; and Letheby states that pigs with scarlet fever and spotted typhus have been used for food with equally harmless results. The flesh of sheep with smallpox had been found to produce vomiting and diarrhœa, sometimes accompanied with fever.

One obvious suggestion of the immunity from disease recorded in part of the cases above given is that the injurious properties of the flesh had been destroyed by the heat to which it had been subjected in the process of cooking, combined with the antiseptic and protective power of the gastric juice. The subject, however, has not been sufficiently examined to warrant the conclusion that every kind of unsound meat may be rendered innocuous by culinary means.

But even were this so the idea of partaking of meat which had once been unsound, from whatever cause, and, as in the instances above quoted, with the pustules of smallpox, the spots generated by typhus, and the rash of scarlet fever upon it, becomes unspeakably repulsive and revolting. But we must not be misled because of the difficulty of reconciling the contradictory statements above given, nor by the evidence some of them appear to afford as to the innocuous character of diseased meat, since it is just possible that closer and more prolonged observation of the facts may have led to different conclusions. Thus, for example, pork, infested with that formidable entozoon, the _Trichina spiralis_, had been partaken of for years, under the impression that it was a perfectly healthy food, until Dr Zencker, of Dresden, discovered that the parasite was the cause of a frightful disease, which he called _Trichinosis_, and which had hitherto baffled all attempts to find out its origin. Dr Letheby, writing on this subject, says: “I have often had occasion to investigate cases of mysterious disease, which had undoubtedly been caused by unsound meat. One of these, of more than ordinary interest, occurred in the month of November, 1860. The history of it is this:——A forequarter of cow-beef was purchased in Newgate Market by a sausage-maker who lived in Kingsland, and who immediately converted it into sausage-meat. Sixty-six persons were known to have eaten of that meat, and sixty-four of them were attacked with sickness, diarrhœa, and great prostration of vital powers. One of them died; and at the request of the coroner I made a searching inquiry into the matter, and I ascertained that the meat was diseased, and that it, and it alone, had been the cause of all the mischief.”[29]

[Footnote 29: Letheby, ‘Lectures on Food,’ Longman and Co.]

Here are two instances in which but for subsequent investigation the evil effects narrated would not have been debited to diseased meat, but to some other cause.

“One of the principal and by far the most prolific sources of food-poisoning is the sausage, the eating of which, in Germany more particularly, has caused the death of a number of persons.

The sausages in which these poisonous qualities occasionally develop themselves are the large kinds made in Wurtemburg, in which district alone they have caused the deaths of more than 150 out of 400 persons during the last fifty years. The poisonous character of the sausage is said to develop itself generally in the spring, when it becomes musty, and also soft in the interior. It is then found to be acid to test paper, and to have a very disagreeable and tainted flavour.

Should it be eaten when in this state, after from about twelve to twenty-four hours the patient is attacked with severe intestinal irritation in the form of pains in the stomach and bowels by vomitings, and diarrhœa.

To these symptoms succeed great depression, coldness in the limbs, weak and irregular pulse, and frequent fainting fits. Should the sufferer be attacked with convulsions, and difficult respiration, the seizure generally ends in death. The nature of the poisonous substance that gives rise to these effects in the sausage has not yet been determined. Liebig believed them to be due to the presence in the meat of a particular animal ferment, which he conceived acted on the blood by catalysis, and thus rendered it diseased. Others have surmised that a poisonous organic alkaloid may have been produced in the decaying meat; and others again that the effects may have been caused by some deleterious substance of a fatty nature. M. Van den Corput was of opinion that the mischief was due to the presence in the meat of a poisonous fungus, which he calls a _sarcina botulina_. This last theory receives support from the fact that a peculiar mouldiness is always to be observed in these dangerous sausages, and that this is coincident with the development of their poisonous qualities.

Several effects have been produced by other kinds of animal food——as veal, bacon, ham, salt-beef, salt-fish, cheese, &c., and the food has usually been in a decayed and mouldy condition. It would be tedious if I were to detail, or even to enumerate the cases recorded by medico-legal writers; but I may perhaps refer to a few of them. In 1839 there was a popular fête at Zurich, and about 600 persons partook of a repast of cold roast veal and ham. In a few hours most of them were suffering from pain in the stomach, with vomiting and diarrhœa; and before a week had elapsed nearly all of them were seriously ill in bed. They complained of shiverings, giddiness, headache and burning fever. In a few cases there was delirium, and when they terminated fatally there was extreme prostration of the vital powers. Careful inquiry was instituted into the matter, and the only discoverable cause of the mischief was incipient putrefaction and slight mouldiness of the meat.” A case is recorded by Dr Geisler of eight persons who became ill from eating bacon which was mouldy; and another by M. Ollivier of the death of four persons out of eight, all of whom had partaken of partially decomposed mutton.

If some of the foregoing statements fail to demonstrate that the act of partaking of diseased meat is a necessary source of danger to health, there can be no such doubt as to the pernicious and perilous consequences which ensue when meat is consumed containing in its tissues the ova and larvæ of certain parasitic creatures. If the fleshy part of a piece of measly pork be carefully examined, it will be found to be more or less dotted about with a number of little bladder-like spots, in size about as large as a hemp-seed.[30]

[Footnote 30: See article “Cysticerci.”]

If now we carefully rupture one of these little bodies or cysts, there will be found in it a minute worm, which under the microscope will be seen to have a head from which proceed a number of little hooks that perform a very disagreeable office should the parasite be taken into the human stomach by any one making a meal off measly and undercooked pork. For, then, being liberated from its sac, or nidus, by the action of the gastric juice of the stomach on this latter, the creature passes into the intestines. To these it attaches itself by means of the hooklets on its head, and instantly becomes a tapeworm, which grows by a succession of jointed segments it is able to develop, and each one of which is capable of becoming a separate and prolific tapeworm filled with countless eggs.

These eggs reach the land through the agency of manure (for they are found in the intestines of the horse), and from this source they get into the stomachs of pigs and oxen, where they hatch not into tapeworm, or _tenia_, but, travelling through the animal’s stomach, burrow into its muscular tissue. Here they establish and envelop themselves in the little cyst or small bladder-like substance, whose presence, as explained, constitutes the condition called “measly” pork, and here they remain dormant until such time as, taken into the stomach, they may again become tapeworms, to be again expelled and to perpetuate by their ova the round of metamorphosis. From the circumstance of their being met with enclosed in little sacs or cysts, these parasites have been termed _Cysticerci_. The variety of them we have just been considering as occurring in pork is called the _Cysticercus cellulosæ_, whilst the tapeworm to which it gives rise is known as the _Tinea solium_.

Another variety of _Cysticercus_ is met with in the flesh of the ox, the cow, and the calf. In the human body this also develops into a tapeworm called the _Tinea mediocanellata_. Tapeworm is a very common disease in Russia and Abyssinia, and its prevalence is no doubt due to the habit of giving the children in those countries raw meat to suck, under the impression that the child is strengthened in consequence. From experiments made by Dr Lewis it was found that a temperature of 150° F., maintained for five minutes, was sufficient to destroy these cysticerci.

Another and more formidable entozoon, communicable by unsound meat, is the _Echinococcus hominis_,[31] which represents one of the metamorphoses of the _Tinea echinococcus_, the tapeworm of the dog. In Iceland, where a sixth of the population are said to suffer from the ravages of the _Echinococcus hominis_, it is the custom to feed the dogs on the flesh of slaughtered animals affected with this parasite, which in the body of the dog develops into a tapeworm. The innumerable eggs which the worm produces are, however, incapable of being hatched in the dog’s intestines. They have to find another and more suitable habitat, and this is secured for them as follows:——Segments of the tapeworm, with their countless ova, being voided with dog’s excrement, fall into the running water, and on to the fields and pastures, whence they gain their entrance into the stomachs of human beings, oxen, and sheep. Here the eggs become hatched, not into tapeworms, but into _Echinococci hominis_, or prospective tapeworms. Burrowing through the membranes of the stomach, the echinococcus establishes itself most commonly in the liver, but not unfrequently in the spleen, heart, lungs, and even the bones of man. In the animal economy they enclose themselves in little sacs or cysts, and give rise to the most alarming and painful diseases, which hitherto have proved incurable. They attack the brain in sheep, and are the cause of the disease known as “staggers.” Sheep are also infested by another parasite known as the _Distoma hepatica_, the ravages of which give rise in the sheep to that devastating disease——“the rot.” The creature is also known by the name of the “liver-fluke,” since it principally attacks this important organ in the animal. The liver-fluke is of constant occurrence in the livers of diseased sheep, and unless destroyed by thorough cooking will of course pass into the human economy. The embryo fluke gains admission to the sheep’s body through the instrumentality of small snails, to the shells of which it attaches itself. In wet weather the snails crawl over the grass of the meadow which forms the pastures of the sheep, and are swallowed by it. Once in the sheep’s stomach the embryo becomes a fluke, and commences its depredations on the animal’s liver. After this, the reason why the rot attacks sheep after a continuance of wet weather will be evident.

[Footnote 31: See article “Echinococcus hominis.”]

The most terrible of all the meat parasites is a minute worm about 1/30th of an inch long, found in the flesh of pork. This creature, which is named the _Trichina spiralis_ (from the form it assumes when coiled up in the little cyst or capsule which encloses it), when it gets conveyed into the human stomach with improperly cooked or underdone pork, soon becomes liberated from its confinement owing to the destruction of its envelope by the gastric juice. Once in the stomach the parasite grows rapidly, giving birth to innumerable young _trichinæ_, which, by first boring through the membranes of the alimentary canal, pierce their way through the different parts of the body into the muscular tissue, where they become encysted, and where they remain until conditions favorable to their liberation again occur.

Until such time, however, as they have become enclosed in the cyst, their movements give rise to indescribable torture, and to a disease known as _trichinosis_, of which it has been estimated more than 50 per cent. of those attacked by it die. The symptoms of trichinosis commence with loss of appetite, vomiting, and diarrhœa, succeeded after a few days by great fever——resembling, according to Dr Aitken, that of typhoid or typhus. As might be expected the pains in the limbs are extreme. Boils and dropsical swellings are not unusual concomitants of the malady.

Hitherto this frightful disease has been mostly confined to Germany, where there have been several outbreaks of it since its discovery in 1860 by Dr Zencker. Feidler says that only free _trichinæ_ are killed by a temperature of 155° F.; and that when they are in their cysts a greater heat may be necessary. From what has been said the importance of efficient cooking must become manifest. There must always be risk in underdone pork, whether boiled or roasted. In the pig, the trichina, if present, may always be found in the muscles of the eye. In Germany the makers of pork sausages are now said to have these muscles subjected to a microscopic examination previous to using the meat, which, of course, is rejected if the examination has been unfavorable.

The trichinæ, if present in the flesh of pork, may be seen as small round specks by the naked eye, the surrounding flesh itself being rather darker than usual owing to the inflammation set up in it. All doubt, however, on this point may be removed by having recourse to the microscope. Dr Parkes says a power of 50 to 100 diameters is sufficient, and that “the best plan is to take a thin slice of flesh, put it into liquor potassæ (1 part to 8 of water), and let it stand for a few minutes till the muscle becomes clear; it must not be left too long, otherwise the trichinæ will be destroyed. The white specks come out clearly and the worm will be seen coiled up. If the capsule is too dense to allow the worm to be seen, a drop or two of weak hydrochloric acid should be added. If the meat be very fat a little ether or benzine may be put on it in the first place.”

_Legislation relative to meat inspection and seizure._——The law recognising the importance of the supply of pure and wholesome meat gives considerable powers to the different sanitary officers who are appointed to inspect it. See FOOD, INSPECTION OF.

=MEAT, AUSTRALIAN.= See MEAT PRESERVING.

=MEAT BISCUITS.= _Prep._ 1. The flour is mixed up with a rich fluid extract of meat, and the dough is cut into pieces and baked in the usual manner.

2. Wheaten flour (or preferably the whole meal), 3 parts; fresh lean beef or other flesh (minced and pulped), 2 parts; thoroughly incorporate the two by hand-kneading or machinery, and bake the pieces in a moderately heated oven. Both the above are very nutritious; the last more especially so. 1 oz. makes a pint of good soup.

=MEAT, COLD, to Stew.= Let the cold meat be cut into slices about half an inch thick. Take two large-sized onions, and fry them in a wineglass of vinegar; when done, pour them on to the meat; then place the whole in a stewpan, and pour over sufficient water to cover it. After stewing about half an hour add sufficient flour and butter to thicken the gravy, and also pepper, salt, and ketchup, to flavour; then let it simmer gently for another half an hour. Serve up with a little boiled rice around it.

=MEAT EXTRACTS.= Some preparations of this nature have been already noticed under the heads ESSENCE and EXTRACT; the following are additional and highly valuable formulæ:——

_Prep._ 1. (Dr Breslau.) Young ox-flesh (free from fat) is minced small, and well beaten in a marble mortar, at first alone, and afterwards with a little cold or lukewarm water; the whole is then submitted to the action of a press, and the solid residuum is treated in the same manner, with a little more cold water; the juice (reddish in colour) is now heated to coagulate the albumen, strained, and finally evaporated in a water bath to the consistence of an extract. As ordinary flesh contains only 1% of kreatine, while that of the heart, according to Dr Gregory, contains from 1·37% to 1·41%, this is the part employed by Dr Breslau. The product possesses an agreeable odour and taste; and is easily soluble in water.

2. (Falkland.) Fresh lean beef (or other flesh), recently killed, is minced very fine, and digested, with agitation, in cold water, 1 pint, to which hydrochloric acid, 6 drops, and common salt, 1 dr., have been added; after about an hour the whole is thrown upon a fine hair sieve, and the liquid portion allowed to drain off without pressure, the first portions that pass through being returned until the fluid, at first turbid, becomes quite clear and transparent; when all the liquid has passed through, cold water, 1/4 pint, is gently poured on, in small portions at a time, and allowed to drain through into that previously collected. The product is about 3/4 pint of cold extract of flesh, having a red colour, and a pleasant, soup-like taste. It is administered cold to the invalid——a teacupful at a time, and must on no account be warmed, as the application of even a very slight heat causes its decomposition and the separation of a solid mass of coagulated albumen. This cold extract of flesh is not only much more nutritious than ordinary beef tea, but also contains a certain quantity of the red colouring matter of blood, in which there is a much larger proportion of the iron requisite for the formation of blood-particles. The hydrochloric acid also greatly facilitates the process of digestion. This formula is a modification of the one recently recommended by Liebig for the preparation of a highly nutritive and restorative food for invalids.

3. (EXTRACTUM SANGUINIS BOVIS——Dr Mauthner.) Pass fresh blood (caught from the slaughtered animal) through a sieve, evaporate it to dryness in a water bath, and when cold rub it to powder.——_Dose_, 10 to 20 gr., or more, per diem, in a little water.

_Obs._ The above preparations are intended to supersede the inefficient compounds——beef tea, meat soups, &c.——during sickness and convalescence. MM. Breslau and Mauthner describe their extracts of flesh and blood as being peculiarly advantageous in scrofulous exhaustion, exhaustion from anæmia, diarrhœa, &c. The extract of Falkland or Liebig is represented as having been employed both in the hospitals and in private practice at Munich with the most extraordinary success. It is said to be capable of assimilation with the least possible expenditure of the vital force.

=Meat, Fluid.= This preparation consists of lean meat, in which the albumen has been changed so as to be non-coagulable by heat, and the fibrin and gelatin from their normal insoluble condition to one admitting of their being dissolved in water.

In this soluble condition, the first stage effected in stomach digestion, the several bodies are known as peptones or albuminose, and the proportion of their simple constituents remains the same as in ordinary fibrin, albumen, and gelatin.

The alteration is effected by finely mincing meat and digesting it with peptone, hydrochloric acid, and water, at a temperature of about 100° Fahr., until dissolved.

The solution is then filtered, the bitter principle, formed during the digestion, removed by the addition of a little pancreatic emulsion, and the liquor, which has been neutralised by the addition of carbonate of soda, evaporated to a thick syrup or extractive consistence.

Fluid meat is the only preparation which entirely represents, and yields the amount of nourishment afforded by, lean meat; it differs altogether from beef tea and extracts of meat, as all these contain only a small portion of the different constituents of meat. A patent has been granted to its inventor, Mr Darby.

=Meat, Liebig’s Extract of.= _Syn._ EXTRACT OF FLESH, EXTRACTUM CARNO. This preparation is an aqueous infusion evaporated to the consistence of a thick paste, of those principles of meat which are soluble in water.[32]

[Footnote 32: “Altered as they be by the Application of Heat.” Deane and Brady, ‘Pharmaceutical Journal,’ Oct. 1866.]

It is chiefly composed of alkaline phosphates and chlorides, a nitrogenous crystalline base known as kreatine, various extractive matters, which it has been surmised may have originated in the decomposition of certain nitrogenous bodies, and possibly of a small quantity of lactic acid, as it contains neither albumen nor fibrin, two of the most important and nutritious ingredients of flesh; it must not, therefore, be regarded as a concentrated form of meat. Liebig says that it requires 34 lbs. of meat to yield 1 lb. of this extract——a statement which, as Dr Pavy justly remarks, shows how completely the substance of the meat which constitutes its real nutritive portion must be excluded. This absence of direct nutrient power, now admitted by physiologists, whilst disqualifying the extract as a substitute for meat, does not, however, preclude its use in certain cases of indisposition requiring the administration of a stimulant or restorative, in which circumstances it has been found a useful and valuable remedy, and has been suggested as a partial substitute for brandy where there is considerable exhaustion or weakness, accompanied with cerebral depression and lowness of spirits. In this latter respect its action seems analogous to strong tea.

In the vast pastures of Australia and the pampas of South America are countless herds of oxen and sheep, whose numbers far exceed the food requirements of the comparatively sparse population of those districts. The fat, horns, hoofs, bones, skins, and wool of these cattle, which form the chief part of the wealth of those countries, are exported principally to Europe. Until within a few years, however, no means had been adopted for the utilisation of the superfluous flesh of the animals, beyond employing it as a manure. By manufacturing it, however, into “extract of meat,” this waste has been remedied, and immense works for its preparation are now erected both in South America and in Australia. The process followed by the different makers, although varying in some particulars, is essentially the same, and consists in extracting by water, either hot, cold, or in the form of the steam, those portions of the meat which are soluble in that fluid, and subsequently evaporating the solution so obtained until it becomes of a proper consistence to be put into jars. The extract so obtained keeps well (if all the fat and gelatin are removed), and is most conveniently adapted for exportation. It is said that the extract as being obtained from cattle that have had English progenitors possesses a flavour superior to that which comes from South America, where the animals are of a different and inferior breed.

The following interesting description of the manufacture of “Liebig’s Extract of Meat” is taken from the Buenos Ayres ‘Standard’ of September, 1867. The establishment, of which it is a description, is at Fray Bentos, on the Uruguay, South America. “The new factory is a building which covers about 20,000 square feet, and is roofed in iron and glass. We first enter a large flagged hall, kept dark, cool, and extremely clean, where the meat is weighed, and passed through apertures to the meat-cutting machines. We next come to the beef-cutting hall, where are four powerful meat-cutters, especially designed by the company’s general manager, M. Geibert; each machine can cut the meat of 200 bullocks per hour. The meat being cut is passed to ‘digerators’ made of wrought iron; each one holds about 12,000 lbs. of beef; there are nine of these digerators, and three more have to be put up. Here the meat is digerated by high-pressure steam of 75 lbs. per square inch; from this the liquid which contains the extract and the fat of the meat proceeds in tubes to a range of ‘fat separators’ of peculiar construction. Here the fat is separated in the hot state from the extract, as no time can be lost for cool operation, otherwise decomposition would set in in a very short time.

“We proceed downstairs to an immense hall, sixty feet high, where the fat separators are working; below them is a range of five cast-iron clarifiers, 1000 gallons each, worked by high-pressure steam through Hallet’s tube system.

“Each clarifier is provided with a very ingenious steam-tap. In the monstrous clarifiers the albumen, fibrin, and phosphates are separated. From hence the liquid extract is raised by means of air-pumps, driven by two thirty horse-power engines, up to two vessels about twenty feet above the clarifiers; thence the liquid runs to the other large evaporators. Now we ascend the staircase reaching the hall, where two immense sets of four vacuum apparatus are at work, evaporating the extract by a very low temperature; here the liquid passes several filtering processes before being evaporated in vacuo. We now ascend some steps and enter the ready-making hall, separated by a wire gauze wall, and all the windows, doors, &c., guarded by the same to exclude flies and dust. The ventilation is maintained by patent fans, and the place is extremely clean. Here are placed five ready-making pans constructed of steel plates, with a system of steel discs revolving in the liquid extract.

“These five pans, by medium of discs, 100 in each pan, effect in one minute more than two million square feet evaporating surface.

“Here concludes the manufacturing process. The extract is now withdrawn in large cans and deposited for the following day.

“Ascending a few steps we enter the decrystallising and packing hall, where two large cast-iron tanks are placed, provided with hot water baths under their bottoms; in these tanks the extract is thrown in quantities of 10,000 lbs. at once, and here decrystallising is made a homogeneous mass and of uniform quality. Now samples are taken and analysed by the chemist of the establishment, Dr Seekamp, under whose charge the chemical and technical operations are performed.

“It may be mentioned that the company’s butcher killed at the rate of 80 oxen per hour; separating by a small double-edged knife the vertebræ, the animal drops down instantaneously on a waggon, and is conducted to a place where 150 men are occupied dressing the meat for the factory, cutting each ox into six pieces; 400 are being worked per day.”

Mr Tooth at a meeting before the “Food Committee” held at the Society of Arts in January, 1868, said that he did not claim any difference in the composition of his article (which was made in Australia) as compared with that made by the South American Company.

In the annexed table the composition of some of the extracts of meat of commerce is given:——

+--------------+-------------+-------+---------------+----------+----------+ | | Liebig’s | Tooth,|French Company,|Whitehead.|Twentyman.| | | Company. |Sydney.|South America. | | | +--------------+------+------+-------+---------------+----------+----------+ |Water | 18·56| 16·00| 17·06 | 16·50 | 24·49 | 20·81 | |Extractive, | | | | | | | | soluble in | | | | | | | | alcohol | 45·43| 53·00| 51·28 | 28·00 | 22·08 | 13·37 | |Extractive, | | | | | | | | insoluble | 13·93| 13·00| 10·57 | 46·00 | 44·47 | 59·10 | |Mineral matter| 22·08| 18·00| 21·09 | 9·50 | 8·96 | 6·72 | | +------+------+-------+---------------+----------+----------+ | |100·00|100·00|100·00 | 100·00 | 100·00 | 100·00 | +--------------+------+------+-------+---------------+----------+----------+

The following are the characteristics of extract of meat of good quality. It should always have an acid reaction, its colour should be a pale yellowish brown, and it should have an agreeable meat-like odour and taste. It should be entirely soluble in cold water, and should be free from albumen, fat, and gelatin.

=Meat Pie.= Stew 2 lbs. of beef steak with one small onion, the gravy from which is to be thickened with flour, and flavoured with pepper and salt. Put it into a baking dish, and cover with a lard crust. It should be baked for one hour. The addition of two kidneys will greatly improve the pie.

=Meat (Australian) Pie.= Take 2 lbs. of Australian meat, or 1-1/2 lb. of meat and 1/2 lb. of kidney. Season to taste, pour in a little water, cover with a lard crust, and bake _not more_ than half an hour.

=MEAT PRESERVING.= “The Belgian _Musée de l’Industrie_ notes the following methods of preserving meats as the most deserving of attention amongst those communicated to the French Academy of Sciences, and published in the _Comptes Rendus_. 1. M. Bundet’s method, by which the meat is kept in water acidulated with carbolic acid in the proportion of 1 to 5 parts of acid per 1000 of water. A series of experiments proved that all kinds of meat could thus be kept fresh for lengthened periods, without acquiring an ill taste or odour.

“The meat may be placed in barrels or air-tight tin cases, filled with acidulated water of the strength above specified, and headed up; or the pieces may be packed in barrels or cases in alternate layers with charcoal, pounded small, and saturated with water containing 5/1000 of carbolic acid. The charcoal serves as a vehicle for the antiseptic fluid, and as an absorbent of any gaseous matters given off by the meat. The latter should be wrapped in thin linen covers to prevent the charcoal working its way into the tissues.

“This method, it is suggested, might be employed in curing pork in place of ‘salting,’ or of the more lengthy and costly process of ‘smoking,’ and also for the preservation of poultry, game, butter, eggs, &c.

“2. In the case of South American meat M. Baudet proposes the use of large sacks of caoutchouc. The meat should be packed in them, with alternate layers of charcoal as above described, and each sack, when filled, should be hermetically closed by drawing another empty caoutchouc sack, cap-wise, over it. The caoutchouc, it is supposed, would fetch enough in the market——its low price notwithstanding——to cover expenses of packing and freight, and so permit the meat to be sold in Europe at a very small advance on cost price. If intended for use a second time, the empty bags should be steeped in boiling water for a few minutes, to remove any organic impurities adhering to them.

“3. M. Gorge’s method, which is in use in La Plata, consists in washing and drying the meat, and afterwards steeping in successive waters containing hydrochloric acid and sulphite of soda, and then packing it in air-tight cases holding 1, 5, or 10 kilog. each. Meat thus treated requires to be soaked in warm water for about half an hour before use.

“4. M. Leon Soubeiran has recommended braying and drying, in the fashion adopted by the Chinese and Mongols, as described by M. Simon, French consul in China, in a communication made by him to the Société d’Acclimatation. The _pemmican_ of our Arctic voyagers and the _charqui_ of South America are familiar examples of meat preserved by analogous processes. The late M. Payen, a distinguished member of the Academy, insisted upon the great perfection to which this system might be carried by the aid of hot-air stoves and suitable apparatus.”

Besides the foregoing, numerous patents have from time to time been taken out, and processes proposed for the preservation of meat; so as to enable it to be sent from those distant countries, such as South America, Australia, Canada, &c., where it is greatly in excess of the wants of the population, to other lands, in which the supply is as much below the demand, and the meat at such a price as to preclude its being regularly used as an article of food by the body of the people.

As the putrefactive changes set up in dead flesh are dependent upon the combined influences of moisture, air, and a certain temperature, it follows that most of the various methods of meat preservation resolve themselves into so many different efforts to remove the meat from the operation of one of the conditions above specified as necessary for its decomposition.

The _charqui_ or jerked beef of South America affords an example of meat preserved by means of being deprived of moisture. It occurs in thongs or strips which have been prepared by placing freshly killed meat between layers of salt and drying them in the sun. _Charqui_, although it retains its soundness for a great length of time, and is rendered eatable by soaking in water and prolonged cooking, is difficult of digestion and wanting in flavour, and if any fat be associated with it, this is liable to become rancid.

_Pemmican_ is meat which, after being dried and powdered, is mixed with sugar and certain spices, both of which assist to preserve the meat as well as to improve its flavour, and to remove the tendency to rancidity caused by any fat that may be accidentally present.

Another process for the preservation of meat by means of desiccation is that of MM. Blumenthal and Chollet, who, in 1854, obtained a patent for preparing tablets composed of dried meat and vegetables, which, after being several times dipped into rich soup, were dried in warm air after each immersion.

At a meeting of the Food Committee, held at the Society of Arts, in May, 1868, specimens of dried beef and mutton in powder, from Brisbane, were shown by Mr Orr, who said they had been dried on tinned plates by means of steam. Dr A. S. Taylor, F.R.S., who examined the sample, found it perfectly fresh and good. It had been prepared at least six months previously.

At a subsequent meeting, the Committee reported that the soup prepared from this desiccated meat, with the addition of a small quantity of vegetables, was considered very successful, and the Committee were of opinion that meat so preserved was likely to prove a valuable and cheap addition to the food resources of the people.

The specimen from which the soup was made had been in the Society’s possession, and formed part of the contents of a tin opened upwards of two years ago. The preservation was perfect.

We have only space briefly to describe some of the more prominent of the processes which have been devised for the preservation of meat by excluding atmospheric air.

Mr Tallerman, a large importer of Australian meat, stated in evidence before the Food Committee of the Society of Arts, in May, 1870, that in the preservation of the meat he sent over to this country he had recourse to a very old practice, which was that of packing the joints in fat, the meat being previously salted or cured. Instead of the meat being packed in brine, the casks with the meat are filled up with melted fat.

In Mr Warrington’s patent, which dates from 1846, it is proposed that animal substances shall be preserved by enveloping them in a layer of glue, gelatin, or concentrated meat gravy, or otherwise by dipping them in warm solutions of such substances, or by wrapping them in waterproof cloth, or by covering them with caoutchouc, gutta percha, or varnish, or thin cream of plaster of Paris, which when set was saturated with melted suet, wax, or stearin.

The patent of Prof. Redwood, which resembles Mr Warrington’s in seeking to exclude atmospheric air by surrounding the meat with an impervious substance, claimed the use of paraffin for this purpose, the paraffin being afterwards coated with a mixture of gelatin and treacle, or gelatin and glycerin. The paraffin is easily removed from the meat by plunging this latter into boiling water, which dissolves the outer coating of gelatin mixture, and at the same time melts the paraffin and liberates the enclosed joint.

Messrs Jones and Trevethick’s patent consisted in exhausting of air the vessel containing the meat, then forcing into it a mixture of nitrogen and sulphurous acids, and subsequently soldering the apertures. Dr Letheby says meat, fish, and poultry preserved in this manner have been found good after seven or eight years; and specimens of them were exhibited in the London Exhibition of 1862.

The removal, however, of atmospheric air from the vessels containing the meat it is designed to preserve is now principally accomplished by means of steam. The germ of this idea originated with M. Pierre Antonie Angilbert more than half a century ago, but the modification of Angilbert’s process, which in principle is that generally adopted by the importers of Australian and South American _cooked_ meat, as well as by the English preparers of the article, originated with Messrs Goldner and Wertheimer, nearly forty years since, and, briefly, is as follows:——The freshly killed meat is placed in tins, with a certain quantity of cold water. The tins and their contents are then securely soldered down, with the exception of a small opening not larger than a pin-hole, which is left in the lid. The tins are next placed in a bath of chloride of calcium, the effect of which is to heat the water in them up to the boiling point, and after a certain time to more or less cook the meat contained in them. When the meat is thought to be sufficiently cooked, and whilst the steam arising from the boiling water is escaping from the aperture, this last is carefully soldered down, the steam not only having driven out all the atmospheric air from the vessel, but in the act of escaping having prevented the ingress of any from without. To still further guard against the entrance of air, the tins are covered over with a thick coating of paint.

Previously to their being allowed to leave the preserving works they are tested by being placed for some time in an apartment in which the temperature is sufficiently high to set up putrefactive action in the meat if any air has been left in the tins, the evidence of which would be the bulging out of the tins, owing to the liberation of certain gaseous products of decomposition. When no distension from inside takes place, the result is considered satisfactory, and the vessels are regarded as properly and hermetically sealed. In some cases the vessels, instead of being heated in a bath of chloride of calcium, are exposed to the action of steam. If the operation be successfully performed, the meat so prepared will keep perfectly good avid sound for years.

Mr Richard Jones effects the removal of the air from the vessels containing the meat as follows:——The meat is put into the tins and entirely soldered up, with the exception of a small tube about the size of a quill, which is soldered on the top of the tin. This tube is placed in connection with a vacuum chamber, and the air exhausted from the tin by means of it. In cooking the meat he also employs a chloride of calcium bath.

Dr Letheby, in one of his Canton Lectures on Food, delivered in 1865, speaking on this part of the subject, and on the above method of meat preservation, says:——“To-night, through the kindness of Messrs Crosse and Blackwell, I am able to show you a specimen of preserved mutton which has been in the case forty-four years, and you will perceive that it is in excellent condition. It formed part of the stores supplied by Messrs Donkin and Gamble, in 1824, to His Majesty’s Exploring ship _Fury_, which was wrecked in Prince Regent’s Inlet in 1825, when the cases were landed with the other stores, and left upon the beach.

“Eight years afterwards, in August, 1833, they were found by Sir John Ross in the same condition as they were left; and he wrote to Mr Gamble at the end of that year, saying, ‘that the provisions were still in a perfect state of preservation, although annually exposed to a temperature of 92° below and 80° above zero.’ Some of the cases were left untouched by Sir John Ross; and after a further interval of sixteen years the place was visited by a party from Her Majesty’s ship _Investigator_, when, according to a letter from the captain, Sir James Ross, ‘the provisions were in excellent condition, after having lain upon the beach, exposed to the action of the sun, and all kinds of weather, for a period of nearly a quarter of a century.’ Messrs Crosse and Blackwell have placed the original letters in my hands for perusal, and they show beyond all doubt that meat preserved in this manner will keep good for nearly half a century——in fact, the case of boiled mutton now before you has been preserved for forty——four years.”

The generality of the samples of preserved meat from Australia are excellent in quality and flavour,[33] except that in most cases the meat has been overcooked, which has arisen from the too prolonged contact of the meat with the steam, which it is judged necessary shall be generated in such quantities as to ensure the certainty of the exclusion of the air. Another inconvenience attending the process, viz. the liability of the sides of the tin to collapse, owing to the vacuum formed in its interior, has been remedied by the introduction into the vessel of some inert gas, such as carbonic acid, or nitrogen.

[Footnote 33: The Food Committee of the Society of Arts, who have carefully and impartially examined numerous samples of Australian and South American preserved meat, say: “It is perfectly sweet and fresh, but somewhat insipid from overcooking, and it seems likely the flavour could be improved if the duration of exposure to heat could be shortened without endangering the preservation.”]

Preserved meat at the present time forms a very considerable article of export both from Australia and South America. In the former country there are several establishments of a colossal character, where the work of tinning the meat is carried on, in many of which establishments hundreds of cattle are slaughtered daily. The largest establishments of the kind are at Sydney and Melbourne, whence extensive shipments are being constantly made. The following figures are taken from the Board of Trade returns:——

_Value of Meat preserved otherwise than by Salting._

Imports from Total Australia. Imports.

1871 £481,093 £610,228 1872 657,945 816,463 1873 557,552 733,331 1874 509,698 757,001 1875 249,611 592,196

Since 1876 tinned meat has been imported from North America.

Several methods have been proposed for the preservation of meat by subjecting it to such conditions that the surrounding temperature should be sufficiently low to arrest putrefaction. In Mr Harrison’s process the reduction of temperature was effected by the application of melting ice and salt, made to run down the outside of the iron chambers containing the meat. It is affirmed that although the joints submitted to this treatment were solidly frozen, no loss of either flavour or immediate decomposition of the meat took place. Mr Harrison’s experiment was perfectly successful in Australia, but broke down during the voyage of a large cargo of meat shipped from Australia in 1873, owing to a defect in the construction of the ice chamber of the vessel and the failure of the supply of ice.

Of other forms of refrigeration applied for this purpose we may mention the process of M. Tellier, by which he proposes to place (on ship-board or elsewhere) joints of meat in a chamber through which a current of air charged with ether or other volatile substance may be passed, with a view to reduce the temperature to 30° F. Also that of M. Poggiale, from whose report to the Paris Academy of Medicine it appears that in chambers contrived on principles similar to M. Tellier’s, all kinds of butcher’s meat and poultry have been hung for ten weeks, at the end of which time they were found perfectly fresh and wholesome. The agent used in the latter case for the production of cold was methylic ether.

The process, however, of refrigeration which has proved not only the most, but in every respect successful, was first satisfactorily carried out since 1876, in which time large cargoes of dead meat have been constantly sent to our metropolitan markets, as well as to Glasgow, from New York. The following extract from the ‘Dundee Advertiser’ gives some interesting details of this process:——

“As to dead meat, the first sale was held on the 5th of June, when 100 carcases of beef and 72 of mutton were disposed of. Since then there has never been a smaller supply, and on the average about 150 carcases have been sold weekly. Last week 210 carcases were sold, and on Wednesday evening there were no fewer than 33 lorries, each laden with three tons of butcher’s meat. The freight paid for carriage to Glasgow, Liverpool, and London, last week amounted to £1900. Altogether, since the importation began, a million and a quarter pounds of dead meat have been sold in Glasgow. The result of this importation has been a reduction in retail price of 1d. per lb., instead of an increase in price, which must have taken place without the increased supply.

“The oxen are collected chiefly in the states of Illinois and Kentucky. They are there reared in enormous numbers on the prairies. Before they reach New York they are driven over railway for fully a thousand miles. Those animals the carcases of which are to be sent to this country are killed the day before the departure of the steamer. As soon as the carcases are dressed they are put into a cooling room capable of containing 500, and subject to a constant current of cold air, supplied by means of a 25 horse-power engine. This sets the beef and extracts the animal heat. Each carcase is next cut into quarters, and these are sewn up in canvas, and during the night transferred on board the vessel. Six of the Anchor Line mail steamers have been fitted up with refrigeration compartments, constructed on a patented principle specially for the conveyance of meat.

“After the quarters have been hung up in the room the door is hermetically closed. Adjoining the compartment is a chamber filled with ice. Air tubes are connected with the beef room, and through them the animal heat ascends, and by means of a powerful engine it is blown across the ice, and returned to the beef room in a cold state. A temperature of about 38° is thus maintained in the beef-room. If it were to get so low as 32°——freezing-point——the meat would be seriously injured.[34] The heat is, therefore, regulated by a thermometer, and when the temperature gets too low, the speed of the engine is slackened, the normal degree of cold being thus maintained almost without variation during the voyage. Cattle killed on Thursday in New York are sold that day fortnight in Glasgow.”

[Footnote 34: Mr Harrison’s experiments make this statement doubtful.]

The first patent for the preservation of food by means of ice was granted to Mr John Ling in 1845.

Lastly, mention must not be omitted of another method for the preservation of meat, which consists in the application to it of certain antiseptic substances, the action of which in preventing putrefaction is due to their power of destroying minute parasitic organisms of low animal or vegetable life, that would otherwise attack and set up decomposition in the meat. Our ordinary salted meats owe their immunity from decay, as is well known, to the presence in their tissues of common salt. Meat preserved, however, by this means is tough, indigestible, and wanting in many of its most important soluble constituents, which, dissolving part of the salt, run off from the meat and are lost.

Amongst other agents which have been found serviceable as antiseptics, and for which from time to time numerous patents have been taken out, are nitrate of potash, acetate and hydrochlorate of ammonia, the sulphates of soda and potash, and bisulphate of lime. The writer remembers partaking, some years since, of some Canadian turkey, which had been preserved by means of this latter substance, and the turkey having been killed some two months before being eaten. It was perfectly sound and of excellent flavour. In this instance the bird had been sent from Canada, with several others, packed in waterproof casks, filled up with a weak solution of bisulphite of lime.

In some cases the saline solution is merely brushed over the outside of the meat; whilst in others it is injected into the substance of the flesh.

Thiebierge’s process consists in dipping the joints for five minutes into dilute sulphuric acid, of the strength of about ten of water to one of acid. The meat after being taken out is carefully wiped and dried, and is then hung up for keeping.

Sulphurous acid also forms the subject of several patents for the preservation of meat. In the process of Laury, for which a patent was taken out in 1854, the gas was introduced into the vessels containing the food. In that of Belford, for which a provisional specification was granted the same year, the meat was soaked for 24 hours in a solution of sulphurous and hydrochloric acids (the latter being in the proportion of a hundredth of the volume of the former). The addition of the hydrochloric acid was made with the intention of decomposing any alkaline sulphites that might be formed by the combination of the alkaline salts of the meat with the sulphurous acid.

Dr Dewar’s process, which is very similar to the foregoing, proposes, instead of exposing the meat to sulphurous acid fumigation, to immerse it in a solution of the acid of the same strength as that of the British Pharmacopœia. On being taken out of the liquid the meat, or other article, is, as speedily as possible, dried at a temperature not exceeding 140° F., so that the albumen may be preserved simply in a desiccated, and not in a coagulated condition.

In the patent of Demait, which dates from 1855, the meat was directed to be hung up in a properly constructed chamber, and exposed for some time to the action of the gas. More recently, Professor Gamgee has taken out a patent, which is a modification of Demait’s, and which consists in hanging up the carcase of the animal, previously killed when under the influence of carbonic oxide, in a chamber filled with this latter gas, to which a little sulphurous acid has been added, the chamber having been first exhausted of air. The carcase is allowed to remain in the chamber from 24 to 48 hours, after which it is hung in dry air. It is stated that meat subjected to the above treatment has been found perfectly sound and eatable after an interval of five months.

M. Lanjorrois proposes to preserve animal substances from decay by the addition to them of 1 per cent. of magenta. He states the process had been applied to slices of beef, which, after being kept for several months, yielded, after being washed and boiled, very good soup. Commenting on this suggestion for the preservation of meat, the ‘Chemical News’ very sensibly and properly remarks: “It is to be hoped the magenta employed will be free from arsenic.”

The patent of M. de la Peyrouse (which dates from 1873) also consists in excluding the air by enveloping meat in fat. In this process, however, the fat is mixed, when in a melting condition, with a certain quantity of the carbonates of sodium, potassium, and ammonium, as well as with some chlorides of magnesium and aluminium, with the object of preventing the fat becoming rancid and decomposing, and thus imparting a disagreeable flavour to the meat.

In M. George’s process the meat is partially dried, and then steeped in successive waters containing hydrochloric acid and sulphate of soda.

=MECON′IC ACID.= H_{3}C_{7}HO_{7}. _Syn._ ACIDUM MECONICUM, L. A peculiar acid, first obtained by Sertuerner from opium, in 1804.

_Prep._ Meconate of lime is suspended in warm water, and treated with hydrochloric acid. Impure meconic acid crystallises on cooling, and may be purified by repeated treatment in the same way with hydrochloric acid. Its purity is ascertained by its leaving no residue when heated in a platinum or glass capsule.

_Prop._ Meconic acid forms beautiful pearly scales; possesses a sour astringent taste; is soluble in boiling water, and to a less extent in cold; it is also soluble in alcohol. With the acids it forms salts called ‘meconates,’ most of which are crystallisable. Meconate of lime is obtained by heating a solution of chloride of calcium with an infusion of opium made with cold water, and neutralised by powdered marble, and collecting the precipitate. Meconate of potassa is prepared by direct solution of the base in the impure acid obtained from meconate of lime till the liquor turns green, heat being applied, when the salt crystallises out as the liquid cools; it may be purified by pressure and recrystallisation.

_Tests._ Meconic acid is characterised by——1. Turning ferric salts red, and the red colour not being destroyed by the action of corrosive sublimate.——2. Precipitating a weak solution of ammonio-sulphate of copper green.——3. With acetate of lead, nitrate of silver, and chloride of barium, it gives white precipitates, which are soluble in nitric acid.——4. It is not reddened by chloride of gold.

=MEC′ONIN.= C_{10}H_{10}O_{4}. A white, crystalline, odourless, neutral substance, discovered by Couerbe in opium.

=MECO′NIUM.= See OPIUM.

=MED′ICINES.= However skilful the medical practitioner may be, and however judicious his treatment, both are interfered with, and their value more or less neutralised, if the remedies he orders are not administered precisely according to his instructions. It is the duty of the attendant on the sick to follow implicitly the directions of the physician, as well in exactly complying with his orders as in doing nothing that she has not been ordered to do. At the same time there are exceptions to this rule, in which a suspension of the remedy, or a deviation from the order of the physician, is not only allowable, but is absolutely required. Thus, from idiosyncrasy or some other cause, the remedy in the doses ordered may have no effect, or may produce one widely different from that intended or expected. In such cases it is evident that a strict adherence to the direction of the physician would be productive of evil; but he should be immediately apprised of the circumstance. The common practice of neglecting to administer the doses of medicine at the prescribed time, or after prescribed intervals, and then, to compensate for the omission, giving the medicine more frequently or in larger doses, cannot be too severely censured, as destructive to the welfare of the patient and injurious to the credit of the physician.

For the purpose of disguising the taste of medicine, or lessening their nauseating properties, Dr Pollio has recommended a means founded on the physiological fact that a strong impression on the nerves (whether of vision, hearing, or taste) renders that which follows less perceptible than under the usual circumstances. Instead, therefore, of applying to the mouth agreeable substances after swallowing nauseous medicines, we should prepare it beforehand, in order that the taste of the medicine may not be perceived. Aromatic substances, as orange or lemon peel, &c., chewed just before taking medicine, effectually prevent castor oil, &c., being tasted. In preparing the mouth for bitters, liquorice is the only sweet that should be used, the others creating a peculiarly disagreeable compound taste. We have noticed already the effect of oil of orange peel in correcting the nauseating qualities of copaiba. See DOSE and PRESCRIBING.

=MEDICINES FOR PASSENGER SHIPS.= The annexed scale of medicines, medical stores, and instruments for ships clearing under the Passengers Acts, other than steamships engaged in the North Atlantic trade, has been issued and caused to be published by the Board of Trade, and is intended to supersede the scales hitherto in force.

The quantities mentioned in the scale are for every 100 passengers, when the length of the passage, computed according to the Passengers Act, is 100 days and upwards. Half the quantity of medicines indicated, but the same kind and quantity of medical stores should be taken when the passage is less than 100 days.

_N.B.——There is a separate scale for North Atlantic steam passenger ships._

The medicines are to be prepared according to the British Pharmacopœia, to be plainly labelled in English, and the average doses for an adult stated, according to the British Pharmacopœia.

All bottles are to be stoppered, and all medicines indicated thus (*) are to be marked with a red poison label. All fluid quantities are to be measured by _fluid_ lbs., oz., or dr.

Lbs. oz. dr. Acid, Acetic 0 6 0 *Acid, Carbolic 0 1 0 *Acid, Carbolic (a powder containing not less than 20 per cent. of pure carbolic or cresylic acid) 112 0 0 Acid, Citric 0 3 0 Acid, Gallic 0 1 0 Acid, Hydrocyanic Dil. 0 0 4 Acid, Nitric 0 1 0 Acid, Sulph. Dil. 0 6 0 Æther 0 1 0 Alumen 0 1 0 Ammon. Carb. 0 6 0 Amylum 1 0 0 Argent. Nit. (Stick) 0 0 2 Calx Chlorate 7 0 0 Camphor 0 6 0 Charta Epispatica, 4 sq. ft., in case *Chlor. of Zinc (Burnett’s sol. of) 16 0 0 *Chloroform 0 8 0 Copaiba 0 8 0 Creosote 0 0 2 Cupri Sulph. 0 1 0 Emp. Cantharidis 0 1 0 Ferri et Quiniæ Cit. 0 1 0 Ferri Sulph. 0 0 4 Glycerin 0 6 0 Glycerin Acid. Tannic 0 4 0 *Hydrat. Chloral 0 1 6 Hydrarg. cum Cretâ 0 0 4 Hydrarg. Subchloridi 0 0 4 Lini Farina 6 0 0 Lin. Camph. 0 8 0 Lin. Opii 0 2 0 Lin. Saponis 1 0 0 *Liq. Atropiæ 0 0 1 Liq. Calcis 1 0 0 *Liq. Morphiæ Acetatis 0 1 0 *Liq. Plumbi Subacetatis 0 2 0 Liq. Potassæ 0 2 0 *Liq. Potassæ Permanganatis (B. P. or Condy’s Crimson Fluid) 3 0 0 Magnes. Sulph. 4 0 0 Mist. Sennæ Co. (omit Extract of Liquorice and substitute Aromatic Spirit of Ammonia, 1 oz. to 1 pint of the mixture) 3 0 0 Ol. Croton 0 0 1 Ol. Lini 0 8 0 Ol. Menthæ Pip. 0 0 2 Ol. Morrhuæ 3 0 0 Ol. Olivæ 1 0 0 Ol. Ricini 2 0 0 Ol. Terebinthinæ 1 0 0 *Opium 1 0 0 Plumbi Acetatis 0 1 0 Potassæ Bicarb. Pulv. 0 4 0 Potassii Iodid. 0 2 0 Pulv. Antimonialis 0 0 3 *Pulv. Astringens (double the quantity indicated to be taken to all tropical ports. Pulv. Catechu Co., Pulv. Cretæ Arom. cum Opiô——equal parts) 1 0 0 Pulv. Cretæ Arom. cum Opiô. 0 2 0 Pulv. Ipecac. 0 2 0 Pulv. Ipecac. Co. 0 2 0 Pulv. Jalapæ Co. 0 3 0 Pulv. Potassæ Nitratis 0 4 0 Pulv. Rhei Co. 0 4 0 Pulv. Scammon. Co. 0 0 6 Quiniæ Sulph. (double the quantity indicated to be taken to all tropical ports) 0 1 0 Sodæ Bicarb. 1 0 0 Sp. Æther. Nitrosi 0 8 0 Sp. Ammon. Arom. 0 8 0 Sp. Rectif. 0 4 0 Sp. Sulphur Sublimatum 3 0 0 Syr. Ferri Iodidi 0 4 0 *Sol. Morphiæ Acetat. (a neutral solution containing 4 grains in a drachm, and so marked. To be labelled——for hypodermic injection) 0 0 4 Tr. Arnicæ 0 6 0 Tr. Camphoræ Co. 0 8 0 Tr. Digitalis 0 0 6 Tr. Ergotæ 0 6 0 Tr. Ferri Perchloridi 0 4 0 *Tr. Opii 0 6 0 Tr. Scillæ 0 2 0 Tr. Valerian. Ammon. 0 3 0 Ung. Cetacei 1 0 0 Ung. Hydrargyri 0 2 0 Ung. Hydrargyri Ox. Rub. 0 1 0 Ung. Sulph. 1 0 0 Ung. Zinci 0 2 0 Vin. Colchici 0 1 0 Vin. Ipecac. 0 1 0 Zinci Sulphatis 0 1 0 Desiccated Soup 4 0 0

_All pills to be made and marked +5+ grains._ Pil. Aloes cum Myrrhâ 2 doz. Pil. Col. c. Hyoscy 4 doz. Pil. Hydrarg. 3 doz. Pil. Ipecac. cum Scillâ 5 doz. Pil. Quiniæ 6 doz. Pil. Sapon. Co. 6 doz.

_Medical Stores._ Lint 10 oz. Tow 1 lb. Adhesive Plaster 3 yds. Male Syringe 1 Male Syringe Glass 1 Female Syringe 1 Phials (assorted) 2 doz. Phial corks 6 doz. Sponges 3 Bed-pan 1 Paper of Pins 1 Hernia Truss, 36 in., reversible 1 Paper of Pill Boxes 1 Gallipots 6 Leg and Arm Bandages 6 Calico 3 yds. Flannel Bandages, 7 yds. long, 6 in. wide 2 Flannel 2 yds. Triangular Bandages, base 48 in., sides 33 in. each 2 † Minim Measures 2 † 1 oz. Measures 1 † 2 oz. Measures 1 † Set of Splints 1 † Waterproof sheeting 4 yds. † Oiled Silk 1 yd. † Enema Syringe and Stomach Pump 1 † Box of Small Scales and Weights 1 † Wedgwood Mortar and Pestle 1 Wedgwood Funnel 1 † Spatulas 2 † Authorised Book of Directions for Medicine Chests 1 † British Pharmacopœia 1

† One set only of these articles required, irrespective of number of passengers.

N.B.——Only one set of instruments required, without regard to the number of surgeons, passengers, or the length of the voyage.

_Instruments._

I { 1 Tenaculum. n { 1 Artery Forceps. { 1 Operating ditto. P { 1 Finger Knife. o { 1 Curve Bistoury, Probe Point. c { 1 Curve Bistoury, Spear Point. k { 2 Probes. e { 1 Silver Director. t { 1 Caustic Case. { 1 Scissors. C { 1 Spatula. a { 12 Needles. s { 1 Skein Ligature Silk. e { 3 Lancets. 1 Amputating Saw. 2 Amputating Knives. 1 Bone Forceps. 3 Tooth Forceps. 1 Skull Forceps. 1 Trephine. 1 Elevator. 1 Hey’s Saw. 1 Trephine Brush. 2 Scalpels. 1 Hernia Knife. 2 Trocars and Canulas. 1 Aneurism Needle. 1 Hernia Director. 1 Tourniquet. 2 Silver Catheters (Nos. 4 and 8). 4 Elastic Gum Catheters (Nos. 3, 5, and 7). 1 Clinical Thermometer. 1 Hypodermic Syringe. 1 dozen charged Tubes for Vaccination. 1 Set of Midwifery Instruments.

=MEER′SCHAUM.= _Syn._ ECUME DE MER, L. A native silicate of magnesia. It has a sp. gr. ranging between 2·6 to 3·4; is readily acted on by acids, and fuses before a powerful blowpipe into a white enamel. The finest qualities are found in Greece and Turkey. Its principal application is to the manufacture of tobacco-pipes. The Germans prepare their pipes for sale by soaking them in tallow, then in white wax, and, finally, by polishing them with shavegrass. Genuine meerschaum pipes are distinguished from mock ones by the beautiful brown colour which they assume after being smoked for some time. Of late years some of the pipemakers have produced a composition clay pipe, which closely resembles meerschaum in appearance, and is “warranted to colour well.” The composition, which is comparatively valueless, is made up into pipes of suitable patterns, which are frequently sold to the ignorant for “meerschaums.” See CEMENTS, HYDRAULIC.

=ME′GRIM.= _Syn._ MEAGRIM, HEMICRANIA, L. A pain affecting one side of the head only, often periodic, like an ague, and generally of a nervous, hysterical, or bilious character. It is clavus when there is a strong pulsation, conveying the sensation of a nail piercing the part. See HEADACHE.

=MEG′RIMS.= _Syn._ MEAGRIMS, VERTIGO. In veterinary medicine this term is applied to horses which when at work reel, then stand for a minute dull and stupid, or fall to the ground, and lie partially insensible for a few minutes. “Horses subject to this affection should be driven with a breastplate or pipe collar, so as to prevent pressure on the veins carrying the blood from the head; the bowels should be kept in good order; an occasional laxative is advisable, and a course, either of arsenic or quinine, or of arsenic and iron.” (Dun.)

=MEL′ANCHOLY.= See HYPOCHONDRIASIS and INSANITY.

=MELIS′SIC ALCOHOL.= A substance obtained by Brodie from beeswax. By oxidation it yields ‘melissic acid.’

=MELLA′GO.= The old name for a medicine having the consistence of honey, with a somewhat sweetish taste. Mellago taraxaci is fluid extract of dandelion.

=MELTING-POINT.= The temperature at which solids assume the liquid form.

=MEN′STRUUM.= [L.] A solvent or dissolvent. The principal MENSTRUA employed in chemistry and pharmacy to extract the active principles of bodies by digestion, decoction, infusion, or maceration, are water, alcohol, oils, and solutions of the acids and alkalies.

=MERCU′′RIAL BAL′SAM.= See OINTMENT OF NITRATE OF MERCURY.

=MERCU′′RIAL DISEASE′.= _Syn._ MORBUS MERCURIALIS, HYDRARGYRIASIS, L. This results from the injudicious or excessive use of mercury, or exposure to the fumes of this metal. The common and leading symptoms are a disagreeable coppery taste; excessive salivation; sponginess, tumefaction, and ulceration of the gums; swollen tongue; loosening of the teeth; exfoliation of the jaws; remarkably offensive breath; debility; emaciation; ending (when not arrested) in death from exhaustion. Fever, cachexia, violent purging and griping, a species of eczema (ECZEMA MERCURIALE, LEPRA MERCURIALIS), and other forms of skin disease, are also phases of the same affection, the first of which occasionally proves fatal under the influence of sudden and violent physical exertion.

The treatment, in ordinary cases, may consist in free exposure to the open air, avoiding either heat or cold; the administration of saline aperients, as Epsom salts, phosphate of soda, &c.; the free use of lemon juice and water as a common drink; with weak gargles or washes of chloride of soda or chloride of lime to the gums, mouth, and throat. Severe cases often resist every variety of treatment, and instances are recorded in the medical journals in which the use of even small doses of mercurials, administered by the faculty, have, owing to the peculiar idiosyncrasy of the patients, been followed by the most horrible sufferings, terminating in death.

=MER′CURY.= Hg. _Syn._ QUICKSILVER, HYDRARGYRUM (B. P., Ph. L. E. and D.); MERCURE, VIF ARGENT, Fr.; QUECKSILBER, Ger. A remarkable metal, which has been known from a very early period. The Romans employed it as a medicine externally, as did the Arabs; but the Hindoos were probably the first to prescribe it internally.

_Sources._ The most important are the mines of Idria, in Carniola; Almaden, in New Castile; and New Almaden, in California, where it exists combined with sulphur, under the form of cinnabar. From this ore the pure metal is obtained by distilling it with lime or iron filings, in iron retorts, by which the sulphur it contains is seized and retained, while the mercury rises in the state of vapour, and is condensed in suitable receivers. Quicksilver is commonly imported in cylindrical iron bottles; containing 1/2 cwt. to 1 cwt. each. It is also imported in small quantities from China, contained in bamboo bottles holding about 20 lbs. each.

_Prep._ Mercury, as imported, is usually sufficiently pure for medicinal purposes without any further preparation. Mere mechanical impurities, as floating dust, dirt, &c., may be got rid of by squeezing the metal through chamois leather or flannel, or by filtering it through a small hole in the apex of an inverted cone of paper. It can be further cleaned by shaking well with a little strong nitric acid, washing with distilled water, and drying by blotting paper, or filtering through warm chamois leather.

_Prop., &c._ Mercury, at all common temperatures, is a heavy liquid, possessing a nearly silver-white colour, and a brilliant metallic lustre; solidifies (freezes) at -40° Fahr., and is then ductile, malleable, and tenacious; boils at 662° Fahr., and escapes in colourless transparent vapour, of great density; it also volatilises slowly at the ordinary temperature of the atmosphere. The presence of minute quantities of lead and zinc greatly retard its evaporation at its boiling heat. It unites with oxygen, chlorine, iodine, &c., forming numerous compounds. With the metals it unites to form AMALGAMS. The only acids which act directly on metallic mercury are the sulphuric and nitric, but for this purpose the former must be heated and concentrated. Nitric acid, however, even when dilute and in the cold, dissolves it freely. Pure mercury is unalterable in the air at ordinary temperatures. Sp. gr. 13·59 at 60° Fahr.; about 14· when in the solid state.

_Uses, &c._ Mercury is applied to various purposes in the arts; as the amalgamation of gold and silver, ‘wash gilding,’ the silvering of looking-glasses, the manufacture of barometers and thermometers, and the preparation of several very valuable medicines. In its metallic state it appears to be inert when swallowed, unless it meets with much acidity in the alimentary canal, or is in a state of minute division; its compounds are, however, all of them more or less poisonous.

Mercury has been employed in one or other of its forms in almost _all_ diseases; but each of its numerous preparations is supposed to have some peculiarity of action of its own, combined with that common to all the compounds of this metal. The mercurials form, indeed, one of the most important classes of the materia medica.

_Tests._ 1. _Metallic mercury_ is detected by its liquid condition and volatility; and, when in a finely divided or pulverulent state, by the microscope, or by staining a piece of copper white when the two are rubbed together.

Mercury, when present in combination, can be detected as under:

When intimately mixed with anhydrous sodium carbonate, and heated in a small test-tube, under a layer of the carbonate, decomposition ensues, and a crust of grey sublimate forms on the cooler portion of the tube. When examined by a lens this crust is seen to consist of minute metallic globules. By friction with a bright glass or iron rod these are united into globules, which are visible to the naked eye.

A perfectly clean and bright piece of copper, immersed in a slightly acid solution of mercury, becomes in a short time covered with a grey or whitish stain, which assumes a silvery lustre when gently rubbed with a piece of soft cork or leather, and is removed by the subsequent application of heat. A single drop of liquid may be tested on a bright copper coin in this way.

The plate of copper with the deposit of mercury, obtained as above, after being washed with a weak solution of ammonia, and in distilled water, and dried by pressure between the folds of bibulous paper, may be cut into small pieces, and heated in a test-tube, in order to obtain metallic globules. When the suspected solution contains organic matter, bright copper filings may be employed, and the process modified so as nearly to resemble Reinsch’s test for arsenious acid. According to Orfila, “scraped copper plate” is capable of detecting the presence of 1/80000th part of corrosive sublimate in a solution. MM. Trousseau and Reveil state that a plate of yellow copper (brass) is even more susceptible than one of red copper.

(Smithson’s electrolytic test.) This consists in the use of a polished wire or plate of gold or copper round which a strip or thread of zinc or tin is wound in a spiral direction. The suspected liquid is acidulated with a few drops of hydrochloric acid, and after immersion for a longer or a shorter period (as half an hour to an hour or two), the gold will have become white if any mercury is present. The coil of zinc or tin is then removed from the gold, and the latter, after being washed and dried between the folds of bibulous paper, is heated in a test-tube, to obtain metallic globules, as before.

An ingenious extemporaneous application of the electrolytic test may be made as follows:——Place a drop or two of the suspected liquid on a clean and bright gold or copper coin, and apply a bright key, so that it may at once touch the edge of the coin and the solution. (See _engr._) An electric current will then be established as before, and a white spot of reduced mercury will appear on the surface of the metal, which may be recognised in the manner already explained.

The salts of mercury are divided into two classes——mercurous, where mercury is a monad element, and unites with one atom of chlorine; and mercuric salts, where it plays the part of a dyad element, or unites with two atoms. The latter of these will be taken first.

=Mercury, Pure.= (Ph. B.) _Syn._ HYDRARGYRUM PURUM. Place commercial mercury, 3 lbs., in a glass retort or iron bottle, and applying heat cause 2-1/2 lbs. of the metal to distil over into a flask employed as a receiver. Boil on this for five minutes hydrochloric acid, 3 dr., diluted with distilled water, 9 fl. dr., and having by repeated affusions of distilled water, and decantations, removed every trace of acid, let the mercury be transferred to a porcelain capsule, and dried first by filtering paper, and finally on a water bath.

=Mercuric Salts.= _Tests._ Sulphuretted hydrogen and ammonium sulphide, added in very small quantities, produce on agitation a perfectly white precipitate, which acquires successively a yellow, orange, and brownish-red colour, as more of the test is added; and, ultimately, when the test is added in considerable excess, an intensely black colour. This precipitate is insoluble in excess of the precipitant, potassium hydrate, potassium cyanide, hydrochloric acid, or nitric acid, even when boiling; but it dissolves readily and completely in potassium sulphide and in ‘aqua regia’ with decomposition. These reactions are characteristic.

Ammonia gives a white precipitate.

Potassium hydrate gives a reddish precipitate, turning yellow when the test is added in excess. The presence of ammonia causes the precipitate to be white, and when the solution contains much acid both reactions are imperfect.

Alkaline carbonates give a brick-red precipitate.

Potassium iodide gives a scarlet precipitate, which is soluble in excess, and in alcohol, and solution of sodium chloride.

The alkaline bicarbonates either do not disturb the solution, or only cause a slight degree of opalescence.

=Mercuric Acetate.= Hg(C_{2}H_{3}O_{2})_{2}. _Syn._ PROTACETATE OF MERCURY. _Prep._ By dissolving mercuric oxide in warm acetic acid. It crystallises in brilliant micaceous lamina, soluble in their own weight of cold water, and somewhat more soluble in boiling water. According to Robiquet, this is the basis of Keyser’s antivenereal pills, which do not contain subacetate of mercury, as has been asserted.

=Mercuric Bromide.= HgBr_{2}. _Syn._ PROTOBROMIDE OF MERCURY, HYDRARGYRI BIBROMIDUM. _Prep._ Two equal parts of bromine and mercury and sublime. Soluble reddish mass; resembles the iodide in its action.——_Dose_, 1/20 to 1/8 gr.

=Mercuric Chloride.= HgCl_{2}. _Syn._ PROTOCHLORIDE OF MERCURY, PERCHLORIDE OF MERCURY, BICHLORIDE OF MERCURY, CORROSIVE SUBLIMATE; HYDRARGYRI PERCHLORIDUM (B. P.), HYDRARGYRI BICHLORIDUM (Ph. L.), SUBLIMATUS CORROSIVUS (Ph. E.), SUBLIMATUM CORROSIVUM (Ph. D.), HYDRARGYRI CHLORIDUM CORROSIVUM (Ph. U. S.), HYDRARGYRI MURIAS CORROSIVUS, L. This is the ‘corrosive sublimate’ of the shops.

_Prep._ 1. (Ph. L.) Mercury, 2 lbs.; sulphuric acid, 21-1/2 fl. oz.; boil to dryness, and rub the residuum, when cold, with sodium chloride, 1-1/2 lb., in an earthenware mortar; lastly, sublime by a gradually increased heat.

2. (Ph. E.) Mercury, 4 oz.; sulphuric acid, 2 fl. oz. 3 fl. dr.; pure nitric acid, 1/2 fl. oz.; dissolve, add of sodium chloride, 3 oz., and sublime as before.

3. (Ph. D.) ‘Persulphate of mercury’ (mercuric sulphate), 2 parts; dried sodium chloride, 1 part; triturate, &c., as before.

4. (Ph. B.) Reduce sulphate of mercury, 20 oz., and chloride of sodium, dried, 16 oz., each to fine powder, and having mixed them add black oxide of manganese, in fine powder, 1 oz., thoroughly by trituration in a mortar, place the mixture in an apparatus adapted for sublimation, and apply sufficient heat to cause vapours of perchloride of mercury to rise into the less heated part of the apparatus arranged for their condensation.

_Obs._ In preparing corrosive sublimate, as well as calomel, by the common process, the solution of the mercury is usually made in an iron pot, set in a furnace under a chimney, to carry off the fumes; and the sublimation is conducted in an earthen alembic placed in a sand bath, or in an iron pot, covered with a semi-spherical earthen head. Corrosive sublimate may also be made by the direct solution of mercuric oxide in hydrochloric acid, or by bringing its constituents together in the state of vapour. The latter plan was patented by the late Dr A. T. Thomson.

_Prop._ The mercuric chloride of commerce occurs in white, semi-transparent, crystalline masses, of considerable density; it possesses an intense coppery taste, is soluble in about 16 parts of cold, and in 3 parts of boiling water; the boiling solution deposits its excess of salt in long white prisms as it cools; soluble in alcohol and ether, in the latter so much so that it has even the property of withdrawing it from its aqueous solutions; the addition of hydrochloric acid, ammonious chloride or camphor, increases its solubility in all these menstrua. It is decomposed by contact with nearly all metallic bodies, and in solution by various organic substances, and by exposure to light. Sp. gr. 5·2 (5·14 to 5·42——Liebig). It melts at about 509° Fahr., and boils and volatilises at a higher temperature.

_Tests._ The presence of mercuric chloride may, under most circumstances, be readily detected by the tests given. To distinguish it from other salts, special tests for chlorine or hydrochloric acid must be applied. If on filtering the solution, acidulating it with dilute nitric acid, and testing it with silver nitrate, a cloudy white precipitate be formed, which is insoluble in excess of the precipitant, and in nitric acid, but soluble in ammonia water, and blackened by lengthened exposure to light, corrosive sublimate is shown to be present in the substance examined. Calomel, the only compound of mercury with chlorine besides corrosive sublimate, is an insoluble powder, which could not, therefore, be found in the filtered liquid. Calomel, or the white precipitate formed by the mercurous salt, with hydrochloric acid and the soluble chlorides, is soluble in excess of the precipitant, and is not only insoluble in liquor of ammonia, but is immediately blackened by it.

For the purpose of demonstrating the presence of corrosive sublimate in a highly coloured liquid, or one loaded with organic matter, it is necessary to agitate it for some minutes with an equal volume of ether. After repose for a short time, the ethereal solution is decanted, and allowed to evaporate spontaneously. The residuum (if any) contains the corrosive sublimate, which, after being dissolved in distilled water, is readily recognised by the above characteristics.

When the substance under examination consists of food, or the contents of the digestive canal, or of animal tissue, it is in general necessary to destroy the organic matter in a nearly similar way to that described under ARSENIOUS ACID. The process adopted by Devergie for this purpose consists in dissolving the substance in concentrated hydrochloric acid, and passing a stream of chlorine through the liquid.——Flandin first carbonises the mass with 1/3 or 1/2 its weight of concentrated sulphuric acid, at 212° Fahr., and then saturates the acid in the cold, with dry ‘chloride of lime,’ added in fragments, assisting the action by stirring, and further adding, by degrees, as the matter thickens and becomes white, a sufficient quantity of distilled water.——Lassaigne boils the suspected mixture for some time with a solution of sodium chloride; a method which, according to Orfila, is not sufficiently delicate to withdraw minute portions of mercury from flesh.——Millon agitates organic liquids (more especially blood, milk, &c.) in large flasks containing gaseous chlorine, which is frequently renewed.——Orfila either dissolves the matter in aqua regia, and passes a stream of chlorine through the liquid, or he carbonises it by means of concentrated sulphuric acid, in close vessels.——Personne proceeds by a similar method, but avoids raising the temperature of the substances operated on.——Reveil employs either the last method or that of Millon. In all cases it is advisable to operate in close vessels, on account of the volatility of the bichloride; Orfila’s apparatus consists of a matrass, provided with a bent tube, the one end of which is plunged into a jar of cold distilled water. The corrosive sublimate is found both in the volatilised matter and in the carbonised residuum, and is extracted from the latter by boiling it for 15 or 20 minutes in aqua regia.

When the organic matter has been destroyed by any of the above processes, and a colourless and filtered solution in distilled water obtained, the usual tests may be at once applied. But in this way we can only detect the presence of mercury, but are unable to decide in what way it has entered the system, although we may infer it from other circumstances. It is, therefore, absolutely necessary, in all medico-legal investigations, to previously employ ether (see _above_), in order that we may be enabled to examine the deleterious matter in its original form, or that in which it was swallowed.

_Uses, &c._ Mercuric chloride is employed as an alterative, diaphoretic, and resolvent, in the chronic forms of secondary syphilis, rheumatism, scrofula, cancer, old dropsies, numerous skin diseases, &c.; and externally, as a caustic, in cancer, and made into an ointment, lotion, or injection, in a vast number of skin diseases, ulcers, gleet, &c., and as a preventive of contagion. It acts quicker than the other preparations of mercury, and it is less apt to induce salivation; but it has been said that its effects are less apparent.——_Dose_, 1/10 to 1/4 gr., either made into a pill, or in solution. It is highly poisonous, and must be exhibited and handled with the greatest caution. Its use is contra-indicated in cases complicated with pulmonary affections or nervous derangement.

_Pois._——1. _Symptoms._ Strong coppery or metallic taste; intense pain in the mouth, pharynx, œsophagus, stomach, and intestines; nausea, vomiting (often bloody), diarrhœa, and (sometimes) violent dysentery (these evacuations are generally more frequent than in poisoning by other metallic compounds). After a certain time there is generally an abatement of the severity of the symptoms; the circulation becomes slower, the pulse small and thready, the respiration gentle, and the skin cold; syncope then supervenes, and great general insensibility, always commencing at the pelvic extremities; and sometimes convulsions occur; the secretion of urine is generally diminished, sometimes even entirely suppressed; but the patients always urinate if the sublimate has been employed in a very diluted state, and if drinks have been administered. Death often appears to result from the shock to the nervous system, from intense exhaustion, or from mortification or intense inflammation of the primæ viæ. Poisoning by corrosive sublimate is distinguished from that by arsenic, by the countenance being flushed, and even swollen; whereas, in poisoning by arsenic, it is wholly contracted and ghastly, and by the whitened condition of the epithelium of the mouth.

2. _Antidotes._ White of egg, hydrated ferric sulphide or ferrous sulphide, and gluten, are each of them powerful antidotes. White of egg has proved efficacious in numerous cases. It requires the white of one egg to decompose 4 gr. of corrosive sublimate. (Peschier.) The recently precipitated protosulphuret of iron is, however, according to Mialhe, the antidote par excellence, not only to corrosive sublimate, but to the salts of lead and copper. The gluten of wheat has also been recommended (Taddei); or, what is equally efficacious, wheat flour mixed up with water. When any of the above are not at hand, copious draughts of milk may be substituted. Iron filings have been occasionally used as an antidote. All these substances should be taken in considerable quantities; the dose should be frequently repeated, and the general treatment similar to that in cases of poisoning by arsenic. Vomiting should be, in all cases, immediately induced, to remove, if possible, the poisonous matter from the stomach.

=Mercuric-ammonium Chloride.= HgNH_{2}Cl. _Syn._ AMMONIO-CHLORIDE OF MERCURY, AMMONIATED CHLORIDE OF MERCURY, WHITE PRECIPITATE, LEMERY’S W. P., COSMETIC MERCURY; HYDRARGYRI AMMONIATUM (B. P.), HYDRARGYRI AMMONIO-CHLORIDUM (Ph. L.), HYDRARGYRUM PRECIPITATUM ALBUM (Ph. E.)

_Prep._ 1. (Ph. L.) Mercuric chloride, 6 oz.; distilled water, 3 quarts; dissolve, with heat, and when the solution has cooled, add of liquor of ammonia 8 fl. oz., frequently shaking it; lastly, wash the precipitate with water, and dry it. The formulæ of the Ph. E. & D. are nearly similar.

2. Mercuric chloride and ammonium chloride, of each 1/2 lb.; water, 3 quarts; dissolve, and precipitate with solution of potassium hydrate, q. s.

_Prop., &c._ A white, inodorous, light mass, or powder; insoluble in alcohol, partially soluble in boiling water, and wholly dissolved by sulphuric, nitric, and hydrochloric acids, without effervescence. It is totally dissipated by heat. When heated with solution of potash, it exhales ammonia, and assumes a yellow colour. Used to make an ointment, which is employed in herpes, porrigo, itch, and other skin diseases, &c.; and by the lower orders as a dusting powder to destroy pediculi, an application which, from its liberal employment, is not always a safe one. It is highly poisonous, and must not be swallowed.

=Mercuric and Ammonium Chloride.= NH_{4}Cl,HgCl_{2}. _Syn._ CHLORIDE OF MERCURY AND AMMONIUM, SAL ALEMBROTH; HYDRARGYRI ET AMMONII CHLORIDIUM, L. _Prep._ (P. Cod.) From mercuric chloride and ammonium chloride, equal parts, triturated together. “The object in adding the ammonium chloride here is to render the corrosive sublimate more soluble in water. The action of the latter is not otherwise altered.” (Redwood.) It is chiefly used for lotions and injections.

=Mercuric and Quinine Chloride.= _Syn._ CHLORIDE OF MERCURY AND QUININE; HYDRARGYRI ET QUINÆ CHLORIDUM, L. _Prep._ (M’Dermott.) From mercuric chloride, 1 part; quinine chloride, 3 parts; separately formed into saturated solutions with water and then mixed; the crystalline precipitate is collected and dried by a gentle heat.——_Dose_, 1/8 to 1/2 gr., made into a pill with crum of bread; daily, as an alterative in debilitated habits; or combined with opium thrice daily, to produce salivation.

=Mercuric Cyanide.= HgCy_{2} or Hg(CN)_{2}. _Syn._ CYANIDE OF MERCURY; HYDRARGYRI CYANIDUM, H. BICYANIDUM, H. CYANURETUM (Ph. U. S.), L. _Prep._ 1. (Pb. L. 1836.) Ferric ferrocyanide (pure Prussian blue), 8 oz.; mercuric oxide, 10 oz.; distilled water, 4 pints; boil for half an hour, filter, evaporate, and crystallise; wash what remains frequently with boiling distilled water, and again evaporate, that crystals may form. This is Proust’s process. The formula of the Ph. U. S. is similar.

2. (Ph. D. 1826.) Prussian blue (pure), 6 parts; mercuric oxide, 5 parts; distilled water, 40 parts; as the last.

3. (Desfosses.) Potassium ferrocyanide, 1 part, is boiled for 1/4 hour with mercuric sulphate, 2 parts, and distilled water, 8 parts; the deposit is separated by filtration, and the liquid evaporated to crystallising point.

4. (Winckler.) Saturate dilute hydrocyanic acid with mercuric oxide; evaporate and crystallise. Pure.

_Prop., &c._ Heavy, colourless, inodorous, square prisms; tasting strongly metallic; soluble in 8 parts of cold water; slightly soluble in alcohol. Those made by the first two formulæ are of a pale yellow colour. It is transparent and totally soluble in water. The solution, on the addition of hydrochloric acid, evolves hydrocyanic acid, known by its smell; and a glass moistened with a solution of nitrate of silver, and held over it, gives a deposit soluble in boiling nitric acid. When heated it evolves cyanogen, and runs into globules of metallic mercury. It has been administered in some hepatic and skin diseases, and has been proposed as a substitute for corrosive sublimate. (Parent.) It has been said to act directly on the skin and bones, and to have proved useful in allaying the pain of nodes and in dispersing them. (Mendaga.) It is, however, principally used as a source of cyanogen and hydrocyanic acid.——_Dose_, 1/16 to 1/4 gr. (beginning with the smaller quantity), made into pills with crum of bread, or in alcoholic solution; as a gargle or lotion, 10 gr. to water, 1 pint; as an ointment, 10 or 12 gr., to lard, 1 oz.

=Mercuric Iodide.= HgI_{2}. _Syn._ PROTIODIDE OF MERCURY, RED IODIDE OF MERCURY, IODIDE OF MERCURY, BINIODIDE OF MERCURY; HYDRARGYRI IODIDUM RUBRUM (B. P.), HYDRARGYRI IODIDUM, H. BINIODIDUM (Ph. E.), H. IODIDUM RUBRUM (Ph. D.), L. _Prep._ 1. (B. P.) Mercuric chloride (corrosive sublimate), 4; potassium iodide, 5; boiling distilled water, 80. Dissolve the mercuric chloride in 60 of water, and the potassium iodide in the remainder, and mix the two solutions. Allow to stand, decant the supernatant liquor, and collect the precipitate on a filter, wash twice with cold water, and dry at 212° F.

2. (Ph. L. 1836.) Mercury, 1 oz.; iodine, 10 dr.; rectified spirit, q. s. (2 or 3 fl. dr.); triturate until the globules of mercury disappear, and the mixture assumes a scarlet colour, then dry it in the shade, and preserve it in a well-stoppered vessel.

3. (Ph. E.) Mercury, 2 oz.; iodine, 2-1/2 oz.; spirit, q. s.; triturate together as last, dissolve the product, by brisk ebullition, in concentrated solution of sodium chloride, 1 gall., filter whilst boiling hot, wash the crystals that are deposited as the solution cools, and dry them.

4. (Ph. D.) Mercuric chloride, 1 oz.; hot distilled water, 25 fl. oz.; dissolve potassium iodide, 1-1/2 oz.; water, 5 fl. oz.; dissolve; when the solutions are cold, mix them, collect the precipitate on a paper filter, drain it, wash it with distilled water, 10 fl. oz., and dry it at a heat not above that of boiling water.

_Prop., &c._ A bright scarlet powder, insoluble in water, but soluble in alcohol and ether, and in the solutions of several of the iodides and chlorides. It is also soluble in cod-liver oil, and in several other fixed oils. Readily sublimed.——_Dose_, 1/16 to 1/4 gr., dissolved in alcohol or made into a pill; in the same cases as the subiodides, from which it differs chiefly in its greater energy and poisonous qualities.

=Mercuric Oleate.= See OINTMENT OF OLEATE OF MERCURY.

=Mercuric and Potassium Iodide.= HgI_{2}.KI. _Syn._ IODIDE OF MERCURY AND POTASSIUM, IODO-HYDRARGYRATE OF POTASSIUM; HYDRARGYRI ET POTASSII IODIDUM, L. _Prep._ 1. (M. Boullay.) Mercuric iodide, potassium iodide, and water, equal parts; dissolve by heat, and crystallise by evaporation or refrigeration, or gently evaporate to dryness.

2. (Puche.) From mercuric iodide and potassium iodide, equal parts, triturated together.——_Dose_, 1/16 to 1/8 gr., dissolved in water; in the same cases as the biniodide, and in chronic bronchitis, hooping-cough, inflammatory sore throat, &c.

=Mercuric and Potassium Iodo-cy′anide.= _Syn._ HYDRARGYRI ET POTASSII IODO-CYANIDUM, L. _Prep._ To a concentrated solution of mercuric cyanide add a rather strong solution of potassium iodide, and dry the precipitate by a gentle heat.

_Prop., &c._ Small, white, pearly, crystalline plates or scales. It is chiefly used as a test of the purity of hydrocyanic acid. When put into this liquid it is instantly turned red if any mineral acid is present.

=Mercuric Nitrate.= Hg(NO_{3})_{2}. _Syn._ PROTONITRATE OF MERCURY, PERNITRATE OF MERCURY. _Prep._ 1. (NEUTRAL.) This is obtained by solution of mercuric oxide, in excess of nitric acid. The solution, evaporated in a bell-jar over sulphuric acid, yields crystals which are neutral. The same compound is obtained as a crystalline powder when the syrupy liquid is dropped into strong nitric acid.

(Basic.) 1st. 2Hg(NO_{3})HO.H_{2}O. _Prep._ _a._ By saturating hot dilute nitric acid with mercuric oxide. The salt, which is bibasic, crystallises on cooling.

_b._ By dissolving mercury in excess of nitric acid, with heat, until the solution, when diluted with distilled water, ceases to give a precipitate with common salt. It is now a mixed solution of the neutral and bibasic pernitrates; but by evaporation crystals of the latter salt only are deposited. The acid solution (before evaporation) is used as a caustic in cancerous, syphilitic, and other ulcerations; but it frequently produces intense pain, and occasionally the usual constitutional effects of mercury. It was formerly given in similar cases to those in which the bichloride is now employed.——_Dose_ (of the dry salt), 1/20 to 1/12 gr. This is the preparation ordinarily referred to under the name ‘pernitrate of mercury.’

2nd. 2Hg(NO_{3})HO.HgO. _c._ By saturating strong nitric acid with mercury, by heat, throwing the solution into cold water, and collecting and drying the precipitate. This salt, which is tribasic, is also formed when the preceding crystallised salts are put into hot water.

_Obs._ This last preparation is a heavy, yellow powder, but the shade varies according to its basicity, which increases with the temperature of the water employed to effect the precipitation, until, at the boiling temperature, the colour is a dull red. It is extensively employed for the extemporaneous preparation of the ointment of nitrate of mercury, according to the formula on the following label which accompanies each bottle:——“Hydrarg. subnitras.” “Two scruples, mixed with one ounce of simple cerate, make the ung. hydrarg. nit. of the London Pharmacopœia.” We need scarcely add that this statement, so unblushingly uttered, is a dangerous falsehood. An ointment so made possesses neither the quantity of mercury nor of nitric acid employed in the Pharmacopœia preparation, besides wanting many of its most sensible and valuable properties.

=Mercuric Oxide.= HgO. _Syn._ PROTOXIDE OF MERCURY, RED OXIDE OF MERCURY, OXIDE OF M., BINOXIDE OF M., DEUTOXIDE OF M., PEROXIDE OF M.; HYDRARGYRI OXYDUM, H. O. RUBRUM, B. & L. There are several methods by which this substance may be prepared. The following are those which have been ordered at different times in the Pharmacopœias:——

1. By precipitation (HYDRARGYRI BINOXYDUM——Ph. L. 1836.). Mercuric chloride (corrosive sublimate), 4 oz.; distilled water, 6 pints; dissolve and add of liquor of potass, 28 fl. oz.; drain the precipitate, wash it in distilled water, and dry it by a gentle heat.

_Obs._ A bright orange-red powder. It usually contains a little combined water; hence its readier solubility in acids than the oxide prepared by heat. When heated sufficiently it yields oxygen, and the mercury either runs into globules or is totally dissipated. It is entirely soluble in hydrochloric acid. (Ph. L. 1836.) The preparation of the shops has frequently a brick-red colour, and contains a little oxychloride, arising from too little alkali being used.

2. By calcination of the nitrate (RED PRECIPITATE; HYDRARGYRI NITRICI OXYDUM Ph. L. HYDRARGYRI OXIDUM RUBRUM, B. P., Ph. L., Ph. D.) _Prep._ B. P. Mercury, by weight, 8; nitric acid, 4-1/2; water, 2. Dissolve half the mercury in the water and acid, evaporate to dryness, and triturate with the rest of the mercury until well blended. Heat in a porcelain capsule, repeatedly stirring, until acid vapours cease to be evolved.

Mercury, 3 lbs.; nitric acid, 18 fl. oz. (1-1/2 lb., Ph. L. 1836); water, 2 quarts; dissolve by a gentle heat, evaporate to dryness, powder, and calcine this in a shallow vessel, with a gradually increased heat, until red vapours cease to arise. The process of the Ph. E. and D. are similar, except that the Dublin College directs the evaporation and calcination to be performed in the same vessel, without powdering or stirring the mass.

_Obs._ Bright red crystalline scales, which usually contain a little undecomposed pernitrate of mercury; in other respects it resembles the last two preparations. It is more generally used as an escharotic and in ointments than the precipitated oxide. It is volatilised by heat without the evolution of nitrous vapours.

According to Mr Brande it contains about 2-1/2 per cent. of nitric acid. According to Mr Barker the process of the Ph. D. yields the finest coloured product; but Mr Brande states that “the nitrate requires to be constantly stirred during the process, which is usually performed in a cast-iron pot.” On the large scale, the evaporation is generally conducted in a shallow earthen dish, and as soon as the mass becomes dry a second dish is inverted over it, and the calcination is continued, without disturbance, until the process is concluded. The heat of a sand bath is employed. 120 lbs. of mercury, and 48 lbs. of nitric acid (sp. gr. 1·48) yields 112 lbs. of red precipitate. (Brande.)

_Uses, &c._ Red oxide of mercury, whether obtained by calcination or precipitation, possesses the same general properties. It is very slightly soluble in water, but sufficiently so to give that fluid an alkaline reaction, and a metallic taste. It was formerly employed in medicine to induce salivation; but is now chiefly used as an escharotic, either in the form of powder or made into an ointment.——_Dose_, 1/8 to 1 gr., combined with opium. It is very poisonous.

=Mercuric Sulphide.= HgSO_{4}. _Syn._ PROTOSULPHATE OF MERCURY; HYDRARGYRI SULPHAS (Ph. B.), H. PERSULPHAS, H. BIPERSULPHAS, L. _Prep._ 1. (Neutral.)——_a._ By boiling together sulphuric acid and metallic mercury until the latter is wholly converted into a heavy, white, crystalline powder; the excess of acid is removed by evaporation. Equal weights of acid and metal may conveniently be employed.

_b._ (Ph. D. 1826.) Dissolve mercury, 6 parts, in a mixture of sulphuric acid, 6 parts, and nitric acid, 1 part, by boiling them in a glass vessel, and continue the heat until the mass becomes perfectly dry and white. Used to make calomel.

_c._ (Ph. B.) Place 20 oz. of quicksilver in a porcelain capsule with 12 fl. oz. of sulphuric acid, and apply heat until nothing remains but a white, dry, crystalline salt. Used to make perchloride and chloride of mercury.

2. (Basic.) HgSO_{4,2}HgO. _Syn._ TRIBASIC SULPHATE OF MERCURY, TURPETH MINERAL, TURBITH M., QUEEN’S YELLOW, SUBSULPHATE OF MERCURY†, TRIBASIC PERSULPHATE OF M.; HYDRARGYRI SUBSULPHAS, H. S. FLAVUS, TERPETHUM MINERALE, L.——_a._ Dissolve mercury in an equal weight of sulphuric acid by boiling them to dryness, fling the mass into hot water, and wash and dry the resulting yellow powder.

_b._ (Ph. D. 1826.) Mercuric sulphate, 1 part; warm water, 20 parts; triturate together in an earthen mortar, wash well with distilled water, drain, and dry it.

_Prop., &c._ A heavy, lemon-yellow powder, soluble in 2000 parts of cold, and about 600 parts of boiling water. By long-continued washing with very hot water it loses all its remaining acid, and is at length converted into red oxide of mercury.——_Dose._ As an alterative, 1/8 to 1/2 gr.; as an emetic, 3 to 5 gr.; as an errhine, 1 gr.; mixed up with a pinch of liquorice powder or fine snuff. It is a powerful poison, and one of the least useful of the mercurial preparations.

_Obs._ The temperature of the water employed to decompose the neutral sulphate influences the shade of colour of the resulting salt in a similar manner to that pointed out under the nitrate. It is now superseded as a pigment by chrome yellow and orpiment, which are not only more beautiful, but cheaper preparations.

=Mercuric Sulphide.= HgS. _Syn._ PROTOSULPHIDE OF MERCURY, RED SULPHURET OF MERCURY, FACTITIOUS CINNABAR, VERMILION, SULPHURET OF MERCURY, SULPHIDE OF M., BISULPHURET OF M.†; HYDRARGYRI BISULPHURETUM (Ph. B. & Ph. L.), CINNABARIS (Ph. E.), H. SULPHURETUM RUBRUM. L. _Prep._ (Ph. L.) Quicksilver, 24 oz.; sulphur, 5 oz.; melt together, and continue the heat till the mixture swells up, then cover the vessel, remove it from the heat, and when cold, powder and sublime it. (Ph. B.) Quicksilver, 2 lbs.; sulphur, 5 oz.

_Prop., &c._ Mercuric sulphide has a dark-red semi-crystalline appearance in the mass, but acquires a brilliant scarlet colour by powdering. It is tasteless, odourless, and insoluble. It is chiefly used as a pigment; but it is occasionally employed in medicine as a diaphoretic and vermifuge, and in some cutaneous diseases and gout.——_Dose_, 10 to 30 gr.; as a fumigation, about 1/2 dr. is thrown on a plate of iron heated to dull redness. For the last purpose it is inferior to mercurous oxide, owing to the more irritating nature of its vapour.

_Tests._ MERCUROUS SALTS. Sulphuretted hydrogen and ammonium sulphide give black precipitates, insoluble in dilute acids, ammonium sulphide, potassium cyanide, and hot nitric acid, but slightly soluble in sodium sulphide, and decomposed by nitro-hydrochloric acid.

Potassium hydrate and ammonia give black grey or black precipitates, which are insoluble in excess of the precipitant.

Hydrochloric acid and the soluble metallic chlorides occasion a precipitate, which assumes the form of a very fine powder of dazzling whiteness, insoluble in excess, but soluble in aqua regia and liquid chlorine. Potassium hydrate and ammonia turn it dark grey or black.

Potassium iodide gives a greenish-yellow precipitate, soluble in ether, and subliming in red crystals when heated.

=Mercurous Acetate.= Hg(C_{2}H_{3}O_{2}). _Syn._ ACETATE OF MERCURY, SUBACETATE. _Prep._ (P. Cod.) Dissolve mercurous nitrate, 1 part, in water (slightly acidulated with nitric acid), 4 parts, and precipitate the liquid with a solution of sodium acetate, gradually added, until in slight excess; carefully wash the precipitate with cold water, and dry it in the shade.

_Prop., &c._ Small, white, micaceous, flexible scales; insoluble in alcohol; soluble in about 300 parts of water; blackened by light; and carbonised by a strong heat. It has been said to be one of the mildest of the mercurials; but this cannot be the case, as it occasionally acts with great violence on both the stomach and bowels, producing much pain and prostration.——_Dose_, 1/6 to 1 gr., night and morning, gradually increased.

=Mercurous Bromide.= HgBr. _Syn._ SUBBROMIDE OF MERCURY; HYDRARGYRUM BROMIDUM, L. _Prep._ (Magendie.) By precipitating a solution of mercurous nitrate by another of potassium bromide. It closely resembles calomel in both its appearance and properties.——_Dose_, 1 to 5 gr.

=Mercurous Chloride.= HgCl or Hg_{2}Cl_{2}. _Syn._ CALOMEL, SUBCHLORIDE OF MERCURY, MERCURY CHLORIDE; HYDRARGYRI SUBCHLORIDUM (B. P.), HYDRARGYRI CHLORIDUM (Ph. L.), H. C. MITE (Ph. U. S.), CALOMELAS (Ph. E. & D.), L. This substance is one of the best known, and probably the most valuable, of all the mercurials.

_Prep._ 1. (Ph. L.) Mercury, 2 lbs.; sulphuric acid, 21-1/2 fl. oz.; mix, boil to dryness (in a cast-iron vessel), and when the resulting mass has cooled, add of mercury, 2 lbs., and triturate the ingredients in an earthenware mortar until they are well mixed; then add of sodium chloride, 1-1/2 lb., and again triturate until the globules are no longer visible; next sublime the mixture, reduce the sublimate to the finest possible powder, diligently wash it with boiling distilled water, and dry it.——_Prod._ 117 or 118% of the weight of mercury employed.

2. (Ph. F.) Mercury, 4 oz., is dissolved in a mixture of sulphuric acid, 2 fl. oz. 3 fl. dr., and nitric acid, 1/2 fl. oz., by the aid of heat; when cold, mercury, 4 oz., is added, and the remainder of the process is conducted as before.

3. (CALOMELAS SUBLIMATUM.——Ph. D.) Sulphate of mercury, 10 parts; mercury, 7 parts; dry sodium chloride, 5 parts; triturate, &c., as before, and afterwards resublime it into a large chamber or receiver.

4. (Ph. B.) Same as Dublin.

5. (Apothecaries’ Hall.) Quicksilver, 50 lbs., and sulphuric acid, 70 lbs., are boiled to dryness in a cast-iron vessel; of the dry salt, 62 lbs. are triturated with quicksilver, 40-1/2 lbs., until the globules are extinguished, when sodium chloride, 34 lbs., is added, and after thorough admixture the whole is sublimed, &c., as before.——_Prod._ 96 to 100 lbs.

6. (Jewel’s Patent.) The receiver, which is capacious, is filled with steam, so that the calomel vapour is condensed in it in a state of extremely minute division. The engr. represents the apparatus now usually employed when this plan is adopted. The product is extremely white, and of the finest quality. It is sometimes called ‘hydrosublimed calomel’ and ‘hydrosublimate of mercury.’ The ‘flowers of calomel,’ of old pharmacy, were prepared in a nearly similar manner.

7. (Soubeiran.) The crude calomel mixture is heated in an earthen tube in a furnace, and a current of air is directed uninterruptedly into the tube by means of a small ventilator. This sweeps away, as it were, the vapours of calomel, and in a straight tube will carry them a distance of 60 feet, to avoid which the end of the recipient is immersed in water, by which means the calomel is moistened and falls down. This plan, slightly modified, is now extensively adopted in this country.

8. (PRECIPITATED CALOMEL; CALOMELAS PRÆCIPITATUM, L.) Digest pure quicksilver, 9 parts, in nitric acid (sp. gr. 1·02 to 1·25), 8 parts, until no more metal will dissolve, applying heat as the effervescence ceases; then mix the hot liquid quickly with a boiling solution of sodium chloride, 8 parts, dissolved in water (slightly acidulated with hydrochloric acid), 64 parts; lastly, well wash the precipitate in boiling distilled water, and dry it. The product, when the process is skilfully managed, is perfectly white and pure.

_Prop._ A heavy, white, tasteless powder; insoluble in water, alcohol, and cold dilute nitric acid; volatilises at a temperature below redness, and yields a white or yellowish-white sublimate; hot nitric acid oxidises and dissolves it; alkalies, the alkaline carbonates, and lime water, decompose it, with the production of the black oxide; ammonia converts it into a dark slate-grey coloured powder (BLACK PRECIPITATE——Kane). Sp. gr. 7·14 (Boullay; 7·156——Pelouze and Fremy; 7·176——Ure).

_Pur._ Calomel is frequently contaminated with small quantities of corrosive sublimate, which may be detected by digesting a little in alcohol, decanting the clear portion, and testing it with a drop or two of potassium hydrate, when a reddish precipitate will be formed if any mercuric chloride be present. It is pulverulent, whitish, and sublimes entirely by heat. It becomes black on the addition of potassium hydrate, then, heat being applied, it runs into globules of mercury. Neither silver nitrate, lime water, nor sulphuretted hydrogen, being added to the water in which it has been washed, or boiled throws down anything.

_Uses._ Calomel is one of the milder mercurials, and in this respect takes its position immediately after blue pill, mercury with chalk, and the grey oxide; but it probably ranks before all the other salts of mercury. Universal experience appears to show it to be a most valuable alterative when judiciously administered. With this intention it is given in doses of 1/4 to 1 gr., generally combined with antimonials, as in Plummer’s pill, and repeated every night, or every other night, for some time, followed by a mild saline aperient in the morning. As a purgative, 2 to 5 gr., either combined with or followed by other purgatives, as jalap, rhubarb, senna, colocynth, Epsom salts, &c. As a vermifuge, 2 to 5 gr., over-night, followed by a sufficient dose of castor oil next morning. Combined with opium it is frequently used in various complaints to produce salivation, or bring the system under the influence of mercury. It is also employed as a sedative and errhine, and in a vast number of other indications. It is, indeed, more frequently used, and in a greater variety of complaints, than probably any other medicine.

_Obs._ Of the two methods of preparing calomel, that by precipitation is not only the best, but the most economical. That by sublimation is, however, the one generally adopted in England. Mr Brande states that “a small portion of sodium chloride is apt to remain combined with it, which might affect its medical uses.” Such a contamination is not found in carefully prepared precipitated calomel, although we doubt whether the quantity of it which exists in any of the samples we have met with (being merely a trace) would at all interfere with its therapeutical action; more especially when it is recollected that alkaline chlorides are present in, not merely the primæ viæ, but also in every part of the animal body. The late Mr Fownes, a chemist who was unsurpassed in the accuracy of his researches, and the caution and delicacy with which he expressed his opinions, once assured us that calomel was more easily and cheaply prepared of the best quality by precipitation than by sublimation, and that if, from careless manipulation, it occasionally contained a minute quantity of common salt, this was of much less importance than the contamination of corrosive sublimate, which was frequently present in samples of sublimed calomel.

To produce a superior article of calomel in the dry way is a somewhat difficult task, and the process frequently fails in the hands of inexperienced operators. The solution of the mercury is best made in an iron vessel, and the sublimation should be conducted (preferably) in an earthenware retort with a short but very wide neck, and fitted in a spacious receiver, having a large flat bottom, also of earthenware, and containing a little cold water. On the small scale the heat may be applied by means of a sand bath. The form above given for calomel, by precipitation, produces a large product, perfectly free from corrosive sublimate and mercurous nitrate, and is consequently free from the objections frequently raised against that mode of preparing it.

“The form in which calomel sublimes depends much upon the dimensions and temperature of the subliming vessels. In small vessels it generally condenses in a crystalline cake, the interior surface of which is often covered with beautiful quadrangular prismatic crystals, transparent, and of a texture somewhat elastic or horny. In this state it acquires, by the necessary rubbing into powder, a decided yellow or buff colour, more or less deep, according to the degree of trituration it has undergone. If, on the contrary, the calomel be sublimed into a very capacious and cold receiver, it falls in an impalpable and perfectly white powder, which requires only one elutriation to fit it for use; it then remains perfectly colourless.” (Brande.)

The long-continued action of steam on calomel in a state of minute division is attended by the formation of a small quantity of corrosive sublimate. (Righini.) Boiling water, hot air, and light, also produce a like effect.

=Mercurous Iodide.= HgI. _Syn._ SUBIODIDE OF MERCURY, GREEN IODIDE OF MERCURY, MERCUROUS IODIDE; HYDRARGYRI IODIDUM VIRIDE (B. P.), HYDRARGYRI SUBIODUM, H. IODIDUM (Ph. L.), H. I. VIRIDE (Ph. D.), L. _Prep._ 1. (B. P.) Mercury, 1 oz.; iodine, 278 gr.; rectified spirit, a sufficiency. Rub the iodine and mercury in a porcelain mortar, moistening occasionally with a few drops of spirit, and continue the trituration until the mass assumes a uniform green colour, and no metallic globules are visible.

2. Precipitate a solution of mercurous nitrate by another of mercurous potassium iodide; wash the precipitate, first in a solution of sodium chloride, and then in pure water; lastly, dry it in the shade.

3. (Ph. L.) Mercury, 1 oz.; iodine, 5 dr.; triturate together, gradually adding of rectified spirit, q. s. (about 1 to 2 fl. dr.), until globules are no longer seen; dry the powder, by a gentle heat, in the shade, as quickly as possible, and preserve it in a well-stoppered black glass vessel. The formula of the Ph. D. is similar.

_Prop., &c._ A heavy, greenish-yellow powder; insoluble in water, alcohol, and a solution of common salt; soluble in ether, and slightly so in an aqueous solution of iodide of potassium. “Freshly prepared, it is yellowish. Heat being cautiously applied, it sublimes in red crystals, which quickly turn yellow, and, on access of light, blacken. It is insoluble in a solution of chloride of sodium.” The process of the Ph. L. and F. P. does not answer when larger quantities than 4 or 5 oz. are prepared at once, owing to the great heat generated by the reaction of the ingredients, and the consequent volatilisation of a portion of the iodine, by which the colour of the product suffers.——_Dose_, 1/8 to 1 gr., made into pills; “in syphilis and scrofula, especially where they occur in the same individual.” It is also used externally, in the form of ointment. It is very poisonous.

=Mercurous Nitrate.= HgNO_{3}. _Syn._ SUBNITRATE OF MERCURY; HYDRARGYRI SUBNITRAS, H. NITRAS, H. PROTONITRAS, L. _Prep._ 1. (Neutral.) By digesting mercury in excess of cold dilute nitric acid, observing to remove the short prismatic crystals within a short time after they are formed; these, when drained, and redissolved in water slightly acidulated with nitric acid, furnish crystals of pure neutral mercurous nitrate by cautious evaporation.

2. (Basic.) Deposited after some time, when excess of mercury has been employed as above. A fine crystallised salt.

_Prop., &c._ Both the above are decomposed by water, but the former may be dissolved in a very small quantity without decomposition. When the neutral salt is triturated with an excess of sodium chloride, and water subsequently added, the whole of the mercury is thrown down as calomel, and the filtered supernatant liquid does not contain corrosive sublimate. If this salt is detected, the salt examined contained mercuric nitrate, and if any basic mercurous nitrate was present, the newly formed calomel has a grey or black colour, due to presence of oxide.——_Dose._ Of the neutral salts, 1/16 to 1/8 gr. It is seldom used internally. A solution is sometimes employed as a mild caustic to ulcers; and, more dilute, as a lotion in lepra, porrigo, psoriasis, etc.; or made into an ointment, in the same diseases.

=Mercurous Oxide.= Hg_{2}O. _Syn._ SUBOXIDE OF MERCURY, GREY O. OF M., BLACK O. OF M., MERCUROUS O., DIOXIDE OF M., PROTOXIDE OF M.†; HYDRARGYRI SUBOXYDUM, H. OXYDUM, H. O. CINEREUM, H. O. NIGRUM, L. _Prep._ 1. (Ph. L. 1836.) Calomel, 1 oz.; lime water, 1 gall.; mix, agitate well together, decant the clear liquid after subsidence, and well wash the sediment with distilled water; lastly, drain and dry it, wrapped in bibulous paper, in the air.

2. (Ph. D. 1826.) Sublimed calomel, 1 part; solution of potassium hydrate (warm), 4 parts; triturate together, &c., as last.

3. Briskly triturate calomel in a mortar with pure potassium hydrate, in excess; wash it with water, and dry it in the shade.

_Prop., &c._ A very dark grey or black powder, suffering decomposition by exposure to light and air, becoming olive coloured, from a portion being resolved into metallic mercury and binoxide. Digested for a short time in dilute hydrochloric acid, it remains undissolved, and the filtered liquid is not affected by potassium hydrate, or by ammonium oxalate. It is totally soluble in acetic acid, and entirely dissipated by heat. As a medicine pure mercurous oxide is one of the mildest of the mercurials, and is used both internally and externally; but chiefly as a fumigant, or made into an ointment.——_Dose_, 1/2 gr. to 3 gr. twice a day.

=Mercurous Phosphate=, _Syn._ HYDRARGYRI PHOSPHAS, L. _Prep._ Add a solution of mercurous nitrate (slightly acidulated with nitric acid) to a solution of sodium phosphate, and wash and dry the precipitate which forms. In its physical characters it closely resembles calomel, than which it is said to be more appropriate in certain cases, especially in secondary syphilis. Alkalies turn it black.——_Dose_, 1/4 to 1 gr., made into a pill with sugar and aromatics.

=Mercurous Sulphate.= Hg_{2}SO_{4}. _Syn._ SUBSULPHATE OF MERCURY, SULPHATE OF THE SUBOXIDE OF M., PROTOSULPHATE OF M.†; HYDRARGYRI SUBSULPHAS, L. _Prep._ By adding sulphuric acid to a solution of mercurous nitrate. The salt falls as a white crystalline powder.

=Mercurous Sulphide.= Hg_{2}S. _Syn._ SUBSULPHATE OF MERCURY; HYDRARGYRI SUBSULPHURETUM CUM SULPHURE, H. S. NIGRUM, L. _Prep._ 1. (Pure.) This falls as a black precipitate when a solution of mercurous nitrate is treated with sulphuretted hydrogen or ammonium sulphide.

2. (Impure; ETHIOPS MINERAL; HYDRARGYRI SULPHURETUM CUM SULPHURE, H. S. NIGRUM——Ph. L. 1824 & Ph. D. 1826); (ÆTHIOPS MINERALIS——Ph. L. 1836 & Ph. D. 1826.) (Quicksilver and sulphur, equal parts, triturated together in a stoneware mortar——Ph. D.) until globules are no longer visible.

_Prop., &c._ The last preparation of mercurous sulphide is alone employed medicinally. It is a heavy, insoluble, black powder. It is frequently met with imperfectly prepared, and sometimes adulterated. It is said to be a mixture of mercurous sulphide and sulphur, in variable proportions depending on the length of the trituration. On the large scale it is generally made by melting the ingredients together, and afterwards reducing the mass to a fine powder in a mill or mortar. It is said to be vermifuge and alterative, and has been used in some cutaneous and glandular diseases, but appears to be nearly inert.——_Dose_, 5 to 30 gr.

=Mercurous Tartrate.= (P. Cod.) _Syn._ PROTO-TARTRATE OF MERCURY, HYDRARGYRI TARTRAS. Made by adding a solution of proto-nitrate of mercury in water, slightly acidulated with nitric acid, to a solution of tartrate of potash as long as a precipitate forms. Wash it with distilled water, dry it in the shade, and keep it in bottles covered with black paper.——_Dose_, 1 to 2 gr.

=MERCURY, Other Preparations of.=

=Mercury, Hahnemann’s.= _Syn._ HAHNEMANN’S SOLUBLE MERCURY, H.’S BLACK OXIDE OF M., BLACK PRECIPITATE OF M.; HYDRARGYRI PRÆCIPITATUM NIGRUM, MERCURIUS SOLUBILIS HAHNEMANNI, L.——_a._ By dropping weak ammonia into a solution of mercurous nitrate as long as the precipitate formed is of a black colour; the powder is washed, dried in the shade without artificial heat, and then preserved from the light and air.

(Ph. Bor. 1847.) Solution of mercurous nitrate (recent; sp. gr. 1·1), 9-1/4 oz.; distilled water, 2 lbs.; mix, filter, and add to the solution of ammonia (sp. gr. ·960), 1/2 oz., diluted with water, 4 fl. oz.; collect the powder immediately on a filter, wash it with water, 3 fl. oz., and dry it, &c., as before. A very black powder.——_Dose_, 1/4 to 1 gr.

=Mercury, Precipitates of.= 1. BLACK PRECIPITATE, Hahnemann’s soluble mercury (basic mercurous and ammonium nitrate). 2. GREEN P. (MERCURIUS PRÆCIPITATUS VIRIDIS, LACERTA VIRIDIS), from equal parts of mercury and copper, separately dissolved in nitric acid, the solutions mixed, evaporated to dryness, and then calcined until red fumes cease to arise. Caustic. 3. RED P., mercuric oxide. 4. WHITE P., ammonio-chloride of mercury.

=Mercury, Ward’s.= _Syn._ AMMONIO-NITRATE OF MERCURY; HYDRARGYRI AMMONIÆ NITRAS, L. To nitric acid, 4 parts, contained in a spacious bolt-head or matrass, add, gradually, ammonium sesquicarbonate, 2 parts; afterwards add of mercury, 1 part, and digest in a gentle heat, until the solution is complete.

=Mercury with Chalk.= _Syn._ HYDRARGYRUM CUM CRETÂ. GREY POWDER (B. P.) _Prep._ Rub 1 oz. (by weight) of mercury, and prepared chalk, 2 oz., in a porcelain mortar, until metallic globules cease to be visible to the naked eye and the mixture acquires a uniform grey colour.——_Dose._ From 3 to 8 gr.

A little water is said to aid in the extinction of the mercury. Mr Bottle suggests a slight departure from the Grey _modus operandi_ followed by the British Pharmacopœia in the above preparation. He proposes to substitute for the tedious process of trituration in a porcelain mortar the agitation of the mercury with the chalk in a wide-mouthed glass bottle; by which means the metal may be minutely subdivided, at a considerably less expenditure of time and labour.

=Mercury with Magnesia.= (Ph. D.) _Syn._ HYDRARGYRUM CUM MAGNESIÂ. Pure mercury, 1 oz., carbonate of magnesia, 2 oz. Rub together in a porcelain mortar until the globules cease to be visible and the mixture acquires a uniform, grey colour.——_Dose_, 3 to 8 grains.

=Mercury, Yellow Oxide of.= (Ph. B.) _Syn._ HYDRARGYRI OXYDUM FLAVUM. _Prep._ Perchloride of mercury, 4 oz.; solution of soda (Ph. B.), 2 pints; distilled water, q. s. Dissolve the perchloride in 4 pints of distilled water, adding the solution by the application of heat, and add this to the solution of soda. Stir them together, allow the yellow precipitate to subside, remove the supernatant liquor by decantation, thoroughly wash the precipitated oxide on a calico filter with distilled water, and finally dry it by the heat of a water bath.

=MES′LIN.= A mixture of various kinds of grain. (Brande.)

=METAGAL′LIC ACID.= Obtained by heating dry gallic acid, by a quick fire, to about 480° Fahr., or until it froths, melts, and becomes black and solid, then dissolving the residuum in an alkali, filtering, and precipitating by an acid. An insoluble, black powder.

=ME′TAL.= _Syn._ METALLUM, L. See METALS.

=METAL′LICA.= [L.] Preparations of the metals. One of the divisions of the Ph. L.

=METAL′LIC TREES.= See VEGETATION (Metallic).

=METAL′LO-CHROMES.= A name given by Nobili to extremely thin films of peroxide of lead deposited by electrolytic action upon plates or polished steel, so as to produce an iridescent play of colours. The effect is often very beautiful.

=MET′ALLOIDS.= A name sometimes applied to the NON-METALLIC ELEMENTS.

=METAL′LURGY.= “The art of extracting metals from their ores, and adapting them to various processes of manufacture.” (Percy.)

“Notwithstanding the striking analogy which exists between common chemical and metallurgic operations, since both are employed to isolate certain bodies from each other, there are essential differences which should be carefully noted. In the first place, the quantity of materials being always very great in metallurgy, requires corresponding adaptations of apparatus, and often produces peculiar phenomena; in the second place, the agents to be employed for treating great masses must be selected with a view to economy, as well as chemical action. In analytical chemistry, the main object being exactness of result and purity of product, little attention is bestowed upon the value of the reagents, on account of the small quantity required for any particular process. But in smelting metals upon the large scale, profit being the sole object, cheap materials and easy operations are alone admissible.”[35]

[Footnote 35: ‘Ure’s Dict. of Arts, Manufactures, and Mines,’ 4th edit.]

The limits of this work do not permit of more than a general reference to the leading operations of metallurgy under this head. These are——digging, picking or sorting, stamping or crushing, and washing, included under the general term, ‘dressing ore,’——roasting or calcination, which is either performed with the fuel in contact with the ore, or in reverberatory furnaces; and the liquation or reduction to the reguline form. The application of these processes is noticed under the leading metals. Those who desire to study the subject minutely are referred to the treatises of Dr Percy, Robert Hunt, Karsten, and Le Play.

=MET′ALS.= _Syn._ METALLA, L. Metals are elementary bodies, which are generally distinguished by their lustre and power of conducting heat and electricity. When their solutions are electrolysed, the metals always appear at the electro-negative surface, and are hence termed electro-positive elements.

Formerly, when science was much less advanced than at present, the metals constituted a well-defined class. The properties which were regarded as specially characteristic were physical, and were not founded on chemical relations; thus, lustre and high specific gravity were considered to be essential characters of all metals. But we are now acquainted with metals which have a lower specific gravity than water (lithium, sodium, &c.), and with so-called non-metallic elements which present a strong metallic lustre (carbon in the state of graphite, crystallised silicon). It will therefore be seen that the term ‘metal’ is rather conventional than strictly scientific. By far the greater number of elementary bodies at present known are metals. Their physical characters and leading chemical properties are noticed under each of them in its alphabetical place. The following table exhibits some useful particulars:——

TABLE _of some of the properties of some of the metals._

Names arranged in the order of their /-----------------------/\----------------------\ Ductility. | Malleability. | Gold. | Gold. Silver. | Silver. Platinum. | Copper. Iron. | Tin. Nickel. | Platinum. Copper. | Lead. Zinc. | Zinc. Tin. | Iron. Lead. | Nickel.

Names arranged in the order of their /-----------------------/\----------------------\ Power of conducting | Power of conducting Heat. | Electricity. | Silver. | Silver. Copper. | Copper. Gold. | Gold. Tin. | Zinc. Iron. | Iron. Lead. | Tin. Bismuth. | Lead. | Antimony. | Bismuth.

=METANTIMON′IC ACID.= H_{4}Sb_{2}O_{7}. The name given by M. Fremy to that variety of antimonic acid obtained by decomposing pentachloride of antimony with excess of water. It differs from common antimonic acid in being tetra, and forming two different classes of salts with the acids. The acid metantimoniate of potassium is the only reagent which yields a precipitate with the sodium salts, and is therefore of great value in chemical analysis. It is prepared by fusing antimonic acid with excess of potassa, in a silver crucible, dissolving the fused mass in a little cold water, and allowing it to crystallise in vacuo. The resulting crystals (metantimoniate of potassa), by solution in pure water, are resolved into free potassa and the acid salt. See ANTIMONY.

=METAPEC′TIC ACID.= See PECTIN.

=METAPEC′TIN.= See PECTIN.

=METAPHOSPHOR′IC ACID.= See PHOSPHORIC ACID.

=METHEG′LIN.= _Syn._ HYDROMELI, H. VINOSUM, MELLIS VINUM, L. _Prep._ From honey, 1 cwt.; warm water, 24 galls.; stir well until dissolved; the next day add of yeast, 1 pint, and hops, 1 lb., previously boiled in water, 1 gall.; along with water q. s. to make the whole measure 1 barrel; mix well, and ferment the whole with the usual precautions adopted for other liquors. It contains on the average from 7% to 8% of alcohol. See MEAD.

=ME′THYL.= CH_{3}. The hypothetical radical of PYROXYLIC SPIRIT (WOOD-SPIRIT, METHYLIC ALCOHOL) and the methyl series. It forms a number of compounds analogous to those of ethyl.

=METHYLAMINE.= _Syn._ METHYLIA. CH_{3}H_{2}N. A colourless gas possessing a very powerful odour of ammonia, and a strongly alkaline reaction. It differs from ammonia, however, in being non-inflammable. In other respects it bears a considerable resemblance to it. Water at 55° Fahr. dissolves more than eleven hundred times its bulk of methylamine. It may be easily condensed to a liquid by means of a freezing mixture.

To obtain it nascent hydrogen is made to react on prussic or formic acid. Methylia exists in herring brine, and is a frequent product of the destructive distillation of substances containing nitrogen. Most of its salts are very soluble in water.

=METHYLATED SPIRIT.= A mixture of 1 part of methylic alcohol (wood spirit) and 9 parts of ethylic alcohol (spirit of wine). See SPIRIT.

=METHYLENE CHLORIDE.= CH_{2}Cl_{2}. _Syn._ METHYLENE BICHLORIDE. There are various methods of obtaining this compound:——1. By heating chloroform with zinc filings and dilute sulphuric acid. 2. By acting on methylene iodide with chlorine. In this process prolonged treatment with chlorine, at ordinary temperatures, is required to remove the last traces of iodine. (Buttlerow.) Chloride of methylene is a colourless mobile fluid, having a smell like chloroform, and a burning taste. It is used as an anæsthetic in place of chloroform. According to Dr Armstrong, the substance known as METHYLENE ETHER is a mechanical mixture of bichloride of methylene and ethylic ether. Dr Richardson says of this latter it is not so quick in its action as the methylene chloride, but that it is safer. See ANÆSTHETICS.

=METHYLIC ALCOHOL.= See WOOD SPIRIT.

=MEZE′REON.= _Syn._ GAROU; MEZEREON BARK, MEZEREI CORTEX (B. P.); MEZEREON——Ph. L., E., & D. The dried bark of the _Daphne Mezereum_, mezereon; or _Daphne Laureola_, spurge, or wood-laurel. The “bark of the root of _Daphne Mezereum_,” or spurge olive. (Ph. L.) A stimulant and diuretic. It is employed as a sudorific and alterative, in syphilis, rheumatism, scrofula, and chronic cutaneous diseases, usually in conjunction with sarsaparilla. It has also been used as a masticatory in toothache, paralysis of the tongue, &c. On the Continent it is used as a vesicant. For this purpose it is softened by soaking it in hot vinegar, and is then bound on the part, and renewed after intervals of some hours, until vesication is produced.

=MICE.= See RATS.

=MI′CROSMIC SALT.= NaNH_{4}HPO_{4}, _Syn._ TRIBASIC PHOSPHATE OF SODIUM AND AMMONIUM. _Prep._ 1. Phosphates of soda and ammonia, equal parts; water, q. s.; dissolve separately, mix the solutions, evaporate, and crystallise. A slight excess of phosphate of ammonia aids the crystallisation.

2. (Fownes.) Phosphate of sodium, 6 parts; water, 2 parts; liquefy by heat, and add of sal ammoniac (in powder), 1 part; common salt separates, and after its removal the liquid is concentrated so that crystals may form. Used as a flux in blowpipe assays.

=MI′CROSCOPE.= The value of the microscope in chemistry and the collateral sciences is now so generally acknowledged that it would be folly to do more than merely allude to the subject here.

In the COMPOUND MICROSCOPE, which has quite superseded the ‘simple microscope’ as an instrument of research, the object is magnified in the first instance by the object-glass, and then remagnified by the eye-piece. It follows, therefore, that the magnifying power of the instrument may be increased either by increasing the power of the object-glass or that of the eye-piece. It must be borne in mind, however, that in increasing the power of the eye-piece we do not magnify the object itself in a greater degree, but simply increase the image of the object formed by the object-glass. Any imperfections which may exist in the latter are thus greatly increased. At first the great drawback to the use of the compound microscope was its deficiency in achromatism; but the researches of Mr Lester and Dr Goring led to the achromatising of the object-glass, which was the first of the rapid strides towards perfection made by this instrument during the last twenty years. The two most useful object-glasses are the ‘quarter-inch,’ which should magnify from 200 to 220 diameters, and the ‘inch,’ which should magnify from 30 to 40 diameters. The definition of these glasses should be good, and they should transmit plenty of light. Any lines in a structure examined by them should appear sharp and distinct, and there should be no coloured fringes around the object. It is of great importance that the object-glasses are kept perfectly free from dust. A few shreds of wash-leather of the finest quality should be kept in a pill-box for cleaning them. Before rubbing them with the leather they may be breathed upon, but no whiting or liquid of any kind should be used, as each object-glass, being achromatic, is a very delicate piece of workmanship, consisting of two lenses of flint and crown-glass cemented together by Canada balsam. Compound microscopes are now sold by the best London makers at very low prices. A really good instrument, adapted to most of the wants of the chemical, pharmaceutical, or medical student, may be obtained for five guineas.

The following formulæ for the preparation of the chief substances, together with the principal reagents required in the working of the microscope, are from Dr Lionel Beale’s valuable book, ‘How to Work with the Microscope,’[36]

[Footnote 36: Harrison, 59, Pall Mall.]

_Reagents_——

1. Alcohol, of various strengths.

2. Ether, to dissolve oil globules.

3. Nitric acid (1 part of strong acid to 5 of water)

4. Sulphuric acid (1 to 5).

5. Hydrochloric acid.

6. Acetic acid, glacial and dilute (1 to 5).

7. Chromic acid, very dilute, to harden tissues.

8. Solution of potash, saturated and dilute (1 to 10).

9. Solution of soda (25 gr. of fused soda to 1 oz.).

10. Ammonia (1 part of the strongest solution to 3 of water).

11. Nitrate of baryta, a cold saturated solution of.

12. Nitrate of silver (120 gr. to 2 oz.). These two are for the mineral acids.

13. Oxalate of ammonia in solution. Test for lime.

14. Solution of iodine saturated, _i.e._ 1 to 7000 parts of water. Another solution is——1 gr. of iodine and 3 of iodide of potassium in 1 oz. of distilled water.

1. _Cements._——1. _Brunswick Black._ Boil together 1/4 lb. foreign asphaltum and 4-1/4 oz. of linseed oil (previously thickened with litharge), then mix to a proper consistence with oil of turpentine (about 1 pint).

2. _Gold Size._ Boil 25 parts of linseed oil with 1 of minium and 1/3rd part of umber for 3 hours; pour off the clear fluid, and mix with equal parts of powdered white lead, and yellow ochre, added in small successive portions. Then boil well the whole again, and pour off the clear fluid. It dries slowly, but firmly. Both this and the last are dissolved by turpentine.

3. _Goadby’s Marine Glue._ Dissolve separately in coal naphtha equal parts of shell-lac and india rubber. Mix thoroughly with heat.

4. _Sealing-wax Varnish._ Dissolve the best sealing-wax in enough strong spirit of wine to reduce it to the proper consistence. This is brittle.

5. _Canada Balsam._ This dries spontaneously.

Solutions of shell-lac, gum, and various other cements and glues are employed by microscopic manipulators.

_Preservative Fluids._ Canada balsam, spirit and water, glycerin, solution of gelatin, saturated solution of alum, chloride of zinc, and chloride of calcium, are all used to preserve microscopic objects.

The following formulæ will be found useful:——

1. _Goadby’s Solution._ Bay salt, 4 oz.; alum, 2 oz.; corrosive sublimate, 4 gr.; boiling water, 4 pints. Mix and filter. It may often be more diluted.

2. _Thwaite’s Fluid._ Mix spirit of wine, 1 oz., with creosote sufficient to saturate it; rub up with chalk to form a thin paste, and mix gradually with 16 oz. of water. To this may be added an equal quantity of water, saturated with camphor.

3. _Simple Creosote Solution._ Dissolve creosote, 1 dr., in pyroligneous acid, 1 dr., and mix gradually with cold water, 1 pint.

4. _Passini’s Solution. For blood-globules, nerves, and white tissues generally._ Perchloride of mercury, 1 part; chloride of sodium, 2 parts; glycerin, 13 parts; distilled water, 113 parts.

=MIL′DEW.= _Syn._ RUST, BLIGHT. The mouldy appearance on the leaves of plants produced by innumerable microscopic fungi. The hop, wheat, and the choicest garden fruit trees, are those most commonly attacked. The causes are said to be excess of moisture, and absence of the free circulation of air and sunshine. On the small scale, finely powered sulphur is occasionally dusted over the parts affected, as a remedy.

=MIL′IARY FEVER.= _Syn._ MILIARIA, L. Among the other symptoms are——anxiety and frequent sighing, the perspiration has a strong and peculiar smell, and there is a sensation of pricking on the neck and breast, followed by an eruption of small red pimples, which in two or three days become white vesicles, dry up, peel off, and are succeeded by others. The moist weather of spring and autumn are the periods in which it is most prevalent; and delicate females, particularly in child-bed, are those most liable to its attacks. Sometimes it assumes a malignant character. The _treatment_ of this affection consists chiefly in combating the depression of the system by a supporting diet; but everything that heats or stimulates the skin should be avoided. The apartment should be kept cool and well ventilated, and cooling saline laxatives and bitter tonics, with cooling drinks, should also be had recourse to.

=MILK.= _Syn._ LAC, L. The value of milk as an article of food is clearly shown by the fact of it being sufficient to support, and to increase the growth of, the young of every species of the mammalia; at once supplying materials for the formation of the osseous, fleshy, and liquid portions of the body. “The substances present in milk are wonderfully adapted to its office of producing materials for the rapid growth and development of the animal frame. It contains an azotised matter, casein, nearly identical in composition with muscular flesh, fatty principles, and a peculiar sugar, and, lastly, various salts, among which may be mentioned phosphate of lime, held in complete solution in a slightly alkaline liquid.

“The white and almost opaque, appearance of milk is an optical illusion. Examined by a microscope of even moderate power, it is seen to consist of a perfectly transparent fluid, in which float about numbers of minute transparent globules; these consist of fat surrounded by an albuminous envelope, which can be broken mechanically, as in the churning, or dissolved by the chemical action of caustic potassa, after which, by agitating the milk with ether, the fat can be dissolved.” (Fownes.)

_Comp._ COWS’ MILK, of average quality, contains from 10% to 12% of solid matter when evaporated to dryness by steam heat, and has the mean sp. gr. 1·030; while that of the skimmed milk is about 1·035; and of the cream, 1·0244. (Ure.) The average CREAM of cows’ milk contains 4·5% of butter, 3·5% of curd, and 92% of whey. (Berzelius.) The SKIMMED MILK consists of water, 92·9%; curd, 2·%; sugar of milk, 3·5%; lactic acid, lactate of potassa, and a trace of lactate of iron, ·6%, chloride of potassium, phosphate of potassa, and earthy phosphates (lime), ·2%. (Berzelius.)

The following analysis of fresh milk is by M. Haidlen:——

Water 873·00 Butter 30·00 Casein 48·20 Milk sugar 43·90 Phosphate of lime 2·31 Phosphate of magnesia ·42 Phosphate of iron ·07 Chloride of potassium 1·44 Chloride of sodium ·24 Soda in combination with casein ·42 ———————— 1000.

Professor Wanklyn has devised and published in his excellent little manual ‘Milk Analysis’[37] a process by which a very thorough chemical examination of milk may be accomplished with great facility and expedition.

[Footnote 37: Trubner and Co.]

In his preliminary remarks he condemns, as utterly unreliable and misleading, the inferences to be drawn from those hydrometric instruments, the lactometer or lactodensimeter, and creamometer. “A very little consideration,” he says “will suffice to make intelligible the obliquity of the indications of the lactometer and to show how untrustworthy it must be. The lactometer, as of course will be understood, is simply the hydrometer applied to milk; and readings of the instrument are neither more nor less than specific gravities. The more milk-sugar, and casein, and mineral matter there is in a given specimen of milk, the greater (other things being equal) will be its density or specific gravity, and the higher the lactometer reading.

“If, however, fat globules (as happens in the instance of milk) be diffused through the fluid, then, because fat is lighter than water, the effect of the other milk solids on the gravity of the liquid, will be more or less neutralised. The density of milk-fat is about 0·9, water being 1·0. Now, if a solution of casein and milk-sugar, of specific gravity 1·030, be sufficiently charged with fat globules, its specific gravity may be sent down even below the gravity of water. How much would be required to bring about such a result is a matter of simple calculation.

“This being understood, it will be obvious that if the specimens of milk differ in specific gravity, there must be two distinct and equally valid ways of accounting for the difference.

“The milk with the lower gravity may be milk let down with water, or let down with fat, _i. e._ milk let down by being enriched.”

In support of this last assertion Professor Wanklyn quotes corroborative instances afforded by the examination of different specimens of milk known as ‘strippings,’ these being the last portions of milk yielded by the cow at the termination of the milking. All these ‘strippings’ had a lower specific gravity than normal milk.

Further, Professor Wanklyn points out that the specific gravity of organic fluids is a fallacious index of the amount of solids they may contain, as is illustrated by the fact, that whilst a 10 per cent. solution of chloride of potassium has a specific gravity of 1·065 at 15° C., and a 10 per cent. solution of casein and milk sugar, has a specific gravity of only about 1·035.

The creamometer meets with equal condemnation in Professor Wanklyn’s little book, since different specimens of milk vary considerably in their yield of cream, and a perfectly pure sample of milk may yield less cream than one which has been tampered with.

A complete analysis of milk involves the determination of the water, the fat (the essential constituent of the cream), the casein, milk-sugar, and ash.

The following is an outline of Professor Wanklyn’s neat and ingenious method of analysis:——

By means of an accurately graduated pipette, he first places 5 cubic centimetres of the milk in a small weighed platinum dish (about 14 grammes in weight) just previously ensuring the sample from which the milk is taken being thoroughly mixed.

The dish is then placed over a water-bath (the water in which must be kept vigorously boiling the whole time) for three hours, at the end of which time all the water having been driven off, there will remain in the dish a completely dried up residue.

The increase in weight between the empty dish and the residue, will give the weight of the ‘milk solids’ from 5 c.c. of milk. Of course, if this weight be multiplied by 20, the yield from 100 c.c. of milk will be obtained.

To reduce this to a percentage statement it is necessary to remember that 100 c.c. of average milk weigh 102·9 grammes. The next proceeding consists in the determination of the fat. This is done by treating the dried milk solids resulting from the 5 c.c. of milk with ether. There are several important minutiæ necessary to be observed in connection with this part of the process, for the particulars of which the reader is referred to Professor Wanklyn’s book. Suffice it to say, that if properly performed, the whole of the fat is dissolved by the ether, and being separated from the non-fatty portion of the residue is weighed and calculated as ‘fat.’

If, then, the amount found as fat be deducted from the whole of the milk solids previous to their treatment with ether, the ‘milk solids, not fat,’ will be arrived at. Professor Wanklyn estimates the casein[38] as follows:——He treats the milk solids, not fat, with hot alcohol, by which means he dissolves out from them, and removes the milk-sugar and the soluble chlorides. The remaining residue, consisting of casein and phosphate of sodium (chemically combined with the casein), is dried on a water-bath until it ceases to lose weight. It is then weighed along with the vessel containing it, and ignited. The combined weight of the vessel and phosphate of sodium remaining after ignition being deducted from the weight previous to ignition, the difference is the casein.

[Footnote 38: Under the head “Casein” Prof Wanklyn includes the entire nitrogenous materials of milk.]

Another and quicker method, recommended by Professor Wanklyn, for the determination of the casein, is to measure it by the amount of albuminoid ammonia it is capable of yielding when subjected to the ‘albuminoid ammonia process,’ invented by Messrs Wanklyn, Chapman, and Smith.

The alcoholic solution filtered off from the combined casein and phosphate of sodium, contains the milk sugar and soluble chlorides. It is evaporated to dryness on a water-bath, and the residue with the vessel containing it, is weighed. It is then gently ignited, and the weight of the remaining residue being deducted from the total weight before ignition, gives the yield of milk sugar. Or the milk sugar may be determined by titration with a standard copper solution.

For the determination of the ash it is only necessary to ignite the milk solids from 5 c.c. of milk, in the small platinum dish, by which operation all the organic matter being driven off, that which remains behind constitutes the ‘ash’ and is weighed as such.

It will be obvious that in order to determine with anything like rigid accuracy the quality of any sample of milk by analysis, not only must a normal standard for the purpose of comparison be adopted, but such normal standard must represent very closely and with but little variation the definite composition of all sound and genuine milk.

Professor Wanklyn says that “the following, which is the result of several concordant analyses of country-fed milk, may be taken as representing normal milk. In 100 grammes of milk——

Solids (dry at 100° C) 12·5 grammes. Water 87·5 —————— 100·0

“The 12·5 grammes consist of 9·3 grammes of ‘solids which are not fat,’ and 3·2 grammes of fat.” The above data, which are founded on the examination of a very large number of different samples of milk, are confirmed by the researches of Müller and Eisenstuck, who were employed by the Royal Agricultural Society of Sweden in a similar investigation. The labours of these chemists extended over a twelvemonth, and the result of them was to show that the milk yielded day by day, for a whole year, by a herd of cows was remarkably constant in composition.

Professor Wanklyn gives the following formulæ for the calculation and statement of the results of milk analysis. He says, treating the question quite rigidly, which I believe is the proper way of dealing with it, we arrive at the following:——

_Problem_ 1. Given the percentage of ‘solids, not fat’ (= _a_), in a specimen of sophisticated milk (_i. e._ milk, either watered, or skimmed, or both)——required the number of grammes of genuine milk which was employed to form 100 grammes of it.

_Answer._ Multiply the percentage of ‘solids, not fat’ by 100, and divide by 9·3.

Or—— (100 / 9·3)_a_.

_Problem_ II.——Given the percentage of ‘solids, not fat’ (= _a_), also the percentage of fat (= _b_), in a specimen of sophisticated milk——required the number of grammes of fat which have been removed by skimming from the genuine milk which was employed to form 100 grammes of it.

_Answer._—— (3·2 / 9·3)(_a_ - _b_).

In translating fat into cream, the rule is that a removal of 0·2 gramme of fat equals a removal of 1·0 gramme of cream. This rule is directly founded on experiment. I do not, however, claim a high degree of accuracy for the measurement of the cream.

Finally, a slight refinement may be noticed. If a specimen of sophisticated milk has been produced by both skimming and watering, it will be obvious, on consideration, that the extraneous waters employed in manufacturing 100 grammes of it is equal to the difference between 100 and the quantity of genuine milk employed to make 100 grammes of sophisticated milk, together with a quantity of water equal to that of fat removed by skimming.

Extraneous water = 100(100 / 9·3)_a_ + (3·2 / 9·3)(_a_ - _b_)

= 100[(100 + 3·2) / 9·3](_a_ - _b_)

Save for the purpose of finding out the presence of matters other than an excess of water in the milk (a contingency regarded as very improbable), the estimation of the casein and milk sugar is unnecessary. The determination of the ash is for the object of learning if foreign mineral matters, such as chalk or any other inorganic impurity, are present. Professor Wanklyn says he believes that such like extraneous bodies are never employed. The chief, if not the sole, form of dishonesty are watering and skimming.

The amount of ash, however, is a good criterion as to the extent of dilution that has been practised, a deficient amount being, of course, confirmatory of a watered milk.

The determination of the amount of ‘solids, not fat,’ is, in almost every instance, all that is necessary to enable an opinion to be arrived at as to whether the sample of milk has had water added to it or not.

Out of fifty-six samples of milk supplied to the different London unions in 1873, Professor Wanklyn reports that he found only fifteen unwatered, or nearly unwatered. Of these fifteen samples nine had been skimmed, leaving only six that were at once unwatered and unskimmed. These figures, therefore, show that only about 10 per cent. of the milk supplied in the above year to the Metropolitan unions was genuine. He adds——“It is curious to compare the language of the contract under which (as it appears from Mr Rowsell’s report) the dealer supplied the various unions with milk, with the quality of the article as exhibited by the analysis. ‘New unskimmed milk unadulterated,’ ‘genuine as from the cow,’ ‘best new unskimmed milk, to produce 10 per cent. of cream,’ occur in these contracts.”

_Prop._ These are well known. Perfectly fresh milk is slightly alkaline, but soon becomes acid on exposure to the air, and after a time white coagula of casein (CURDS) separate from it. This change is immediately effected by the addition of rennet or an acid. That from the first, when dried and pressed, constitutes cheese.

_Pur., Tests, &c._ The common frauds practised by the milk-dealers are the addition of water and the subtraction of part of the cream. Sometimes potato starch is added to the milk, to give it a creamy or rich appearance, and this addition is still more frequently made to cream, to increase its consistence and quality.

The presence of potato starch may be determined by boiling some of the milk with a little vinegar, and after separating the coagulum by a strainer, and allowing the liquid to become cold, testing it with solution or tincture of iodine. If it turns blue, starch, flour, or some other amylaceous substance, has been used to adulterate it. In most cases it will be sufficient to apply the test to the unprepared suspected milk.

It has frequently been stated that chalk, plaster of Paris, gum, gelatin, sugar, flour, mucilage of hemp-seed, the brains of animals, and other similar substances, are often added to London milk, but there is no reason to suppose there is any truth in these assertions, as some of these articles are too costly to be used, and the presence of others would so alter the flavour or appearance of the milk, or would so soon exhibit themselves by subsidence, as to lead to their detection.

_Pres._ Milk may be preserved in stout bottles, well corked, and wired down, by heating them, in this state, to the boiling-point, in a water bath, by which means the oxygen of the small quantity of enclosed air becomes absorbed. It must be afterwards stored in a cool situation. By this method, which is also extensively adopted for the preservation of green gooseberries, green peas, &c., milk will retain its properties unaltered for years. A few grains of carbonate of magnesia, or, still better, of bicarbonate of potassa or soda, may be advantageously dissolved in each bottle before corking it.

Under Bethel’s patent the milk or cream is scalded, and, when cold, strongly charged with carbonic-acid gas, by means of a soda-water machine, and the corks are wired down in the usual manner. The bottles should be kept inverted, in a cool place.

An excellent method of preventing milk from turning sour, or coagulating, is to add to every pint of it about 10 or 12 gr. of carbonate or bicarbonate of soda. Milk thus prepared may be kept for eight or ten days in temperate weather. This addition is harmless, and, indeed, is advantageous to dyspeptic patients. According to D’Arcot, 1/2000th part of the bicarbonate is sufficient for the purpose. An excess of alkali used in this manner may be detected by the milk turning turmeric paper brown, even after it has been kept some hours, and by the ash obtained by evaporating a little to dryness, and then heating it to dull redness, effervescing with an acid. (See _below_.)

⁂ Milk should not be kept in lead or zinc vessels, as it speedily dissolves a portion of these metals, and becomes poisonous.

_Concluding Remarks._ The principal difference between cows’ milk and human milk consists in the former containing more casein and less sugar of milk than the latter. The remarkable indisposition to coagulate is another character which distinguishes human milk from cows’ milk. Prof. Falkland, who has practically investigated the subject has prepared a nutritive fluid for infants from cows’ milk, closely resembling that of the healthy adult woman. His process is, however, unnecessarily complicated, and, therefore, unsuited to those who would have to employ it in the nursery. To remove this objection we have adopted the following formula:——Sugar of milk, 2 oz.; hot water, 1/4 pint; dissolve, and, when the liquor has become quite cold, add it to fresh cows’ milk, 3/4 pint, and stir them together. This quantity, prepared morning and evening, will constitute the proper food for an infant of from 5 to 8 months old. More may be allowed it if it ‘craves’ it; but there must be no ‘cramming.’ At first it will be advisable to remove a little of the cream from the milk before adding to it the saccharine solution; but after a few days this will be found to be unnecessary, and, indeed, injurious. One very important particular to be attended to is, the employment of pure cows’ milk, obtained from a healthy grass-fed animal only. With this precaution, and the use of a good FEEDING-BOTTLE, the infant will thrive nearly as well as on the breast of any human female, excepting its mother’s. (See _below_.)

ASSES’ MILK closely resembles human milk in colour, smell, and consistence, but it contains rather less cream. (See _below_.)

EWES’ MILK closely resembles cows’ milk, than which, however, it is slightly richer in cream.

GOATS’ MILK, for the most part, resembles cows’ milk, but its consistence is much greater, and it contains much more solid matter. (See _below_.)

MARES’ MILK, in consistence; is between that of cows’ and human milk. Its cream is not converted into butter by agitation. See BUTTER, CHEESE, LACTIC ACID, &c.

_Milk as a cause or carrier of disease._——Milk of a mother labouring under strong mental emotion is, as is well known, capable of seriously endangering the health of the suckling babe. Payne narrates the case of a woman suffering under a nervous affection whose milk, two hours after an attack of the disease, became viscid, like the white of an egg. Similarly, a deterioration and consequent alteration in properties is induced in the milk of the cow if she be over driven, exhausted, or harassed. The food of the animal likewise exercises an influence on the quality of its milk; thus when cows are fed on turnips, wormwood, decayed leaves, and plants of the cabbage or onion families, the flavour of these substances is imparted to their milk. The milk of animals that have fed on poisonous or deleterious plants is capable of setting up toxic symptoms in human beings partaking of it. In June, 1875, the inhabitants of a certain quarter of Rome were attacked with an epidemic, distinguished by great gastro-intestinal irritation. The cause of the outbreak was traced to the use of goats’ milk, yielded by goats that had eaten of the meadow saffron, the _Colchicum autumnale_. It also appears that in the Western States of America the milk of cows that have fed on the poison-oak, the _Rhus toxicodendron_, has on several occasions given rise to attacks of illness in children, marked by extreme weakness, vomiting, fall in bodily temperature, swollen and dry tongue, and constipation. Boiling seems to remove the dangerous properties of the milk.

Milk, as has been shown by Fuchs, is sometimes infested by a fungus, the _Oidium lactis_ or _Penicillium_, which is capable of giving rise to gastric irritation, and sometimes to severe febrile gastritis.[39]

[Footnote 39: Parkes.]

Although the evidence as to the power of the milk of animals affected with epizootic diseases to convey the particular affection to human beings is contradictory, there is little reason to doubt that soured milk may become a carrier of infection from the ailing or convalescent subject to the healthy one.

Typhoid and scarlet fever have been known to have originated in this manner.

The outbreak of the former malady in Marylebone in 1874 was traced to the contamination of milk by the remains of the water which had been used in rinsing the milk pans. This water had been obtained from a well into which the excrete from a typhus patient had percolated from a privy.

At Leeds a similar outbreak was caused by the absorption by the milk of the typhoid effluvium. In the case of scarlet fever the malady has been conveyed by means of the throat-discharges and cuticle falling into the milk from the persons of servants and others employed in dairies.

=Milk, Al′mond.= See EMULSION and MIXTURE.

=Milk, Arrowroot.= _Prep._ From arrowroot, 1 table-spoonful, first wetted and stirred with a little cold water, afterwards adding, gradually, of boiling water, 1/4 pint; and, lastly, of boiling milk, 1/2 pint; with sugar, spice, wine, &c., to palate. Very nutritious, and excellent in chronic diarrhœa. Some persons employ all milk.

=Milk, Choc′olate.= _Prep._ Dissolve chocolate (scraped), 1 oz., in boiling new milk, 1 pint. Nutritious; but apt to offend delicate stomachs.

=Milk, Cof′fee.= _Prep._ 1. Coffee, 1 oz.; boiling water, 1/4 pint; infuse for 10 or 15 minutes in a warm situation, and add the strained liquid to boiling milk, 3/4 pint.

2. Coffee, 1 oz.; tie it loosely in a piece of muslin, and simmer it for 15 minutes in milk, 1 pint. Both the above have been recommended for persons of spare habits, and for those disposed to affections of the lungs, more especially for the asthmatic.

=Milk, Facti′′tious.= _Syn._ ARTIFICIAL MILK. Of the numerous compounds which have been proposed as substitutes for natural milks, the following are examples:——

1. (FACTITIOUS ASSES’ MILK; LAC ASININUM FACTITIUM, LAC A. ARTIFICIALE, L.)——_a._ Cows’ milk, 1 quart; ground rice, 1 oz.; oringo root (bruised), 1 dr,; boil, strain, and add sugar candy (or white sugar), 1 oz.

_b._ Whites of 2 eggs; lump sugar, 1 oz.; cows’ milk (new), 3/4 pint; mix, then add syrup of tolu, 3/4 oz.

_c._ Water, 1 pint; hartshorn shavings, 1 oz.; boil to a jelly; then add lump sugar, 2 oz.; cool, add new milk, 1 pint; syrup of tolu, 1/2 oz. Used as substitutes for asses’ milk, taken freely as a beverage. A cupful, with or without a spoonful of rum, 3 or 4 times daily, is a popular remedy in consumption and debility.

2. (F. GOATS’ MILK——A. T. Thomson.) Fresh mutton suet (minced), 1 oz.; tie it in a muslin bag, and boil it in cows’ milk, 1 quart; lastly, add of sugar candy, 2 gr. In scrofulous emaciation, and in the latter stages of phthisis. The proportion of suet in the above may be advantageously increased a little. The LAC CUM SERO of Guy’s Hospital is a similar preparation.

3. (F. HUMAN MILK; LAC HUMANUM FACTITIUM, L.)——_a._ See _above_.

_b._ (Rosenstein.) Almonds (blanched), 2 in number; white sugar, 1 dr.; water, 4 fl. oz.; make an emulsion, strain, and add of fresh cows’ milk, 6 fl. oz. As a substitute for the breast in nursing.

=Milk, Preserved′.= _Syn._ MILK POWDER; LACTIS PULVIS, LAC PULVERATUM, L. _Prep._ 1. Fresh skimmed milk, 1 gall.; carbonate of soda (in very fine powder), 1-1/2 dr.; mix, evaporate to 1/3rd by the heat of steam or a water bath, with constant agitation, then add of powdered white sugar, 3-1/2 lbs., and complete the evaporation at a reduced temperature; reduce the dry mass to powder, add the cream (well drained) which was taken from the milk, and after thorough admixture put the whole into well-stoppered bottles or tins, which must be at once hermetically sealed.

2. (Legrip.) Carbonate of soda, 1/2 dr.; water, 1 fl. oz.; dissolve, add of fresh milk, 1 quart; sugar, 1 lb.; reduce it by heat to the consistence of a syrup, and finish the evaporation on plates by exposure in an oven.

_Obs._ About an ounce of the powder agitated with a pint of water, forms an agreeable and nutritious drink, and a good substitute for milk at sea. It may also be used for tea or coffee in a solid form. This process, which is very old, has been recently patented. See MILK (_above_).

The condensed or preserved milk, now in such general use, and which is met with in tins as milk which has been more or less deprived of water by evaporation in _vacuo_. It occurs in the market in two forms——in one simply as condensed milk, and in the other as condensed milk mixed with a large quantity of sugar. Milk preserved as above without sugar will keep only for two or three days; whereas with sugar it may be preserved for an almost indefinite time. Either variety mixed with the proper quantity of water becomes normal milk again, the sweetened kind being, of course, milk with the addition of a considerable amount of cane sugar. Professor Wanklyn says he has examined the principal brands of preserved and condensed milk sent to the London market, and finds they contain their due proportion of fat. He gives the following analyses of the produce of the English Condensed Milk Company:

PRESERVED MILK.

In 100 parts by weight. Water 20·5 Fat 10·4 Casein 11·0 Ash 2·0 Cane and milk sugar 56·1 —————— 100·0

CONDENSED MILK.

Water 51·12 Fat 12·11 Casein 13·64 Milk sugar 20·36 Ash 2·77 —————— 100·00

=Roses, Milk of.= _Syn._ LAC ROSÆ, L. _Prep._ 1. (English.)——_a._ Almonds (blanched), 1 oz.; oil of almonds and white soft soap, of each 1 dr.; rose water, 1 pint; make an emulsion.

_b._ From liquor of potassa and oil of almonds, of each 1 fl. oz.; hot water, 2 fl. oz,; agitate together until mixed, then add of rose water and distilled or filtered soft water, of each 1/4 pint, and again agitate well.

_c._ As the last, but using half a tea-spoonful of salt of tartar for the liquor of potassa.

_d._ (Redwood.) Blanched almonds, 8 oz.; rose water, 3 pints; make an emulsion, add of white Windsor soap, white wax, and oil of almonds, of each 1/2 oz.; previously melted together by a gentle heat; triturate until united, and strain; lastly, add a solution of oil of bergamot, 1/2 oz.; oil of lavender, 1 dr.; and attar of roses, 1/2 dr.; (dissolved in) rectified spirit, 12 oz.

2. (FRENCH.)——_a._ From rose water, 1 quart; tinctures of benzoin and styrax, of each 1 fl. oz.; spirit of roses, 1/2 fl. oz.; rectified spirit, 1/2 fl. oz.; mix.

_b._ (Augustin.) Tincture of benzoin, 1/2 fl. oz.; liquor of carbonate of potassa, 2-1/2 fl. dr.; rose water, 1/2 pint; agitate well together. As a lotion in acne.

_c._ (Gianinni.) Tincture of benzoin, 1 dr.; tincture of balsam of Peru, 20 drops; rose water, 1 pint; as the last.

_d._ (Schubarth.) Almond paste, 3 dr.; rose water, 1/2 pint; tincture of benzoin, 1/2 fl. oz. As before. The addition to the last 3 of a little rectified spirit is an improvement.

3. (GERMAN.) From dilute solution of diacetate of lead (Goulard water), and spirit of lavender, of each 1 fl. oz.; rose water, 6 fl. oz.; soft water, 1 pint.

_Obs._ All the above are used as cosmetic washes, and to remove scurf, pimples, and eruptions, in slight cases.

=Milk, Sa′go.= _Syn._ LAC SAGO, L. _Prep._ (Dr A. T. Thomson.) Sago, 1 oz.; cold water, 1 pint; macerate half an hour, pour off the water, add of milk, 1-1/2 pint, and boil slowly until the sago is dissolved. Very nutritious; also in lieu of arrow-root milk.

=Milk of Sulphur.= _See_ SULPHUR (Precipitated).

=Milk, Thick.= Mix one table-spoonful of flour with a pint of milk, and boil for ten minutes, stirring it well the whole time. It may be flavoured either with a little salt, or sugar.

=Milk, Vanil′la.= _Syn._ LAC VANILLÆ, L. _Prep._ 1. Essence of vanilla, 12 drops; lump sugar, 1 oz.; triturate, and add gradually, new milk, 1 pint.

2. (Bèral.) Vanilla sugar, 1/2 oz.; milk, 16 oz.; dissolve.

=MILK FEVER.= _Syn._ FEBRIS LACTEA, L. A febrile condition of the system that sometimes occurs at the time the milk begins to be secreted after parturition. It often assumes a malignant character. See PUERPERAL FEVER.

=MIL′LET.= _Syn._ MILIUM, L. Several varieties of grain are known by this name. That commonly referred to under the name is the produce of _Panicum miliaceum_ (‘Indian millet’). The husked seeds (MILIUM MUNDATUM) are used to make gruel, and are ground for flour. ‘Turkish millet,’ or ‘Guinea corn,’ is produced by _Sorgham vulgare_; and the ‘German’ and ‘Italian millet’ by species of _Setaria_. In some parts of the world millet flour is used for bread, but it is chiefly cultivated as food for domestic animals.

Letheby says millets are a little more nutritious than rice.

In the subjoined table, is given the composition of three different samples of millet meal, free from bran.

+--------------+-------------+---------------+------------ | | _Panicum_ | _Penicillaria_| _Sorghum_ | |_miliaceum_, | _spicata_ |_vulgare_, | | common | a kind of | Dharra of | | millet. | millet, | the Arabs, | | | much used | Goar of | | | in India | India. | | | under the | | | | name of | | | | Bajia. | +--------------+-------------+---------------+------------ | | | | | Water | 12·22 | 11·8 | 11·95 | Nitrogenous | | | | substances | 9·27 | 10·13 | 8·64 | Dextrin | 9·13 | ... | 3·82 | Sugar | 1·80 | ... | 1·46 | Fat | 7·43 | 4·62 | 3·90 | Starch | 59·04 | 71·75 | 70·23[40] | Silicin | 0·11 | ... | ... +--------------+-------------+---------------+------------

[Footnote 40: With husks.]

=MINCE MEAT.= _Prep._ From stoned raisins, currants, sugar, and suet, of each 2 lbs.; sultana raisins and boiled beef (lean and tender), of each 1 lb.; apples 4 lbs.; juice of 2 lemons; the rind of 1 lemon, chopped very fine; mixed spice, 1/4 lb.; candied citron and lemon peel, of each 2 oz.; brandy, a glassful or two; the whole chopped very fine. It may be varied by adding other spice or flavouring, and by the addition of eggs, or the substitution of chopped fowl or veal for beef, according to the state of the cuisinier.

=MINCE PIES.= Take 3 apples, 3 lemons, 1 lb. of raisins, 3/4 lb. of currants, 1 lb. of suet, 1/4 lb. of raw beef, 2 lbs. of moist sugar, 1/4 lb. of mixed candied peel, 1/4 of a rind of a fresh orange, 1 teaspoonful of powdered mixed spice, composed of equal parts of cloves, cinnamon, and nutmeg, 1/2 pint of brandy, and 1 glass of port wine. Peel the apples and cut out the cores very carefully, and then bake the pieces until they are quite soft. The raisins must be carefully stoned, and the currants well washed, dried, and picked. Chop the suet very finely, as well as the raw meat and lemon-peel. Mix all the ingredients thoroughly together, add the brandy last of all, and press the whole down into a stone jar, and place a piece of paper soaked in brandy on the top. Remove the paper and stir up the mixture thoroughly every three days, replacing the paper. If this is done the mincemeat will keep a long time. To make the pies, roll out some thin puff-paste, butter a small round tin, and line it with a piece of paste, then put in a generous quantity of the mincemeat, cover it over with a similar piece of puff paste, and bake it in a moderate oven. Mince pies are none the worse for being warmed up, but pray take care they are sent to table hot. (Cassell.)

=MINDERE′′RUS’ SPIRIT.= See AMMONIA (Acetate of), and SOLUTION.

=MINERAL CHAME′LEON.= _Prep._ From a mixture of binoxide of manganese and potassa and nitre, equal parts, heated to redness. It must be preserved in a well-corked bottle until required for use.

_Prop., &c._ When dissolved in water, its solution, at first green, passes spontaneously through all the coloured rays to the red, when, if potassa be added, the colour retrogrades until it reaches the original green. The addition of oil of vitriol, or of chlorine, renders the solution colourless. The addition of a weak acid, or even boiling or agitating the liquid, turns it from green to red. See MANGANIC ACID.

=MIN′ÉRALISERS.= Substances which, by association with metallic bodies, deprive them of their usual properties, and impart to them the character of ores. Their removal belongs to metallurgy. The term ‘MINERALISED’ has been applied to caoutchouc, gutta percha, bitumen, &c., which has been combined with sulphur, silica, or metallic matter.

=MIN′IM.= _Syn._ MINIMUM, L. A measured drop, of which 60 are equal to a fluid drachm. The size of drops vary so greatly with different liquids and are also so much influenced by the size and shape of the vessels from which they are poured, that they afford no reliable measure of quantity for medicinal purposes. The poured drop has, in some cases, only 1/3rd the volume of the measured drop, or minim; whilst, in others, it is nearly 3 times as large. According to Mr Durande, “liquids which contain a small proportion of water, afford a small drop; while, on the contrary, liquids containing a large quantity of water furnish a large drop.” “Among liquids containing a large proportion of water, those which are not charged with remedial substances, give a larger and heavier drop than the same liquids when containing extraneous bodies in solution.” In all cases in which the word ‘drop’ is mentioned in this work a minim is intended, and the quantity should be determined by means of a graduated minim measure.

=MIN′IUM.= See RED PIGMENTS.

=MINT.= _Syn._ SPEARMINT, GREEN M.; MENTHA VIRIDIS (Ph. L.), L. “The recent and the dried flowering herb” of _Mentha viridis_. It is aromatic and carminative, but its flavour is less agreeable than that of peppermint. It is employed in flatulence, colic, nausea, diarrhœa, &c.; also to make sauce.

=MIR′RORS.= See AMALGAM (Silvering), SILVERING, SPECULUM METAL, &c.

=MITES.= See ACARI.

=MITH′RIDATE.= _Syn._ DAMOCRATE’S CONFECTION; MITHRIDATIUM, CONFECTIO DAMOCRATIS, L. “This composition originally consisted of but few ingredients; viz. 20 leaves of rue, 2 walnuts, 2 figs, and a little salt. Of this we are informed that Mithridates took a dose every morning, to guard himself against the effects of poison. It was afterwards altered, and the number of the ingredients increased to sixty-one. In this more complex form it contained opium, and was, in effect, an aromatic opiate, of which the confection of opium of the present day may be considered as a simplification. The ‘mithridate’ is still prepared in some shops, and is occasionally, though very rarely, prescribed.” (Med. Lex.) “The formulæ for CONFECTION or ELECTUARY OF CATECHU may be considered as the representatives, in our modern Pharmacopœias, of the once celebrated recipes for CONFECTIO DAMOCRATIS and THERIACA ANDROMACHI.” (Redwood.) Mithridate was formerly conceived to be good for nearly every disease, and an antidote for every known poison.

=MIXTURE.= _Syn._ MISTURA, L. A compound liquid medicine, taken in divided doses. Mixtures are usually extemporaneous preparations, and in prescribing them care should be taken not to bring together substances that decompose each other, nor to order heavy powders, that speedily separate from the body of the liquid by subsidence. EMULSIONS, JULEPS, and MUCILAGES, are included in the ‘MISTURÆ’ of the London Pharmacopœia.

Mixtures are usually dispensed in flat octagonal 6-or 8-oz. bottles, with long necks; or in regular ‘octagons’ with short necks, having the doses marked on the glass, to which the strength of the medicine is made to correspond.

Our remarks respecting ‘DRAUGHTS’ equally apply here. By putting the active ingredients of six draughts into a 6-oz. mixture bottle, and filling it up with distilled water, a mixture will be made of corresponding properties, of which the dose will be 2 table-spoonfuls. When the formula for the draughts includes a decoction or infusion as the vehicle, instead of water, four of them only must be taken, which will then fill the 6-oz. bottle, and the proper dose will be 3 table-spoonfuls, or a small wine-glassful.

The following formulæ embraces the whole of the ‘MISTURÆ’ of the British Pharmacopœia, as well as a few others in general use. These will serve as examples for the like preparations of medicinals which are not included in the list. (See also DRAUGHT, EMULSION, JULEP, WATER, &c.)

=Mixture, Absor′bent.= See MIXTURE, ANTACID.

=Mixture, Aca′cia.= See MIXTURE, GUM.

=Mixture, Ace′tate of Ammo′′nia.= _Syn._ MINDERERUS’S MIXTURE; MISTURA AMMONIÆ ACETATIS, L. _Prep._ From solution of acetate of ammonia, 1-1/2 fl. oz.; nitre, 40 gr.; camphor mixture, 6 fl. oz.; rose syrup, 1/2 fl. oz.——_Dose_, 1 to 3 table-spoonfuls, every third or fourth hour, as a diaphoretic in inflammatory fevers, &c.

=Mixture of Acetic Acid.= _Syn._ MISTURA ACIDI ACETICI. _Prep._ Distilled vinegar, 2 fl. dr.; syrup, 4 fl. dr.; water, 2 fl. oz. A fourth part every three hours. For children with scarlatina.

=Mixture of Aconite.= (Mr Fleming.) _Syn._ MISTURA ACONITI. _Prep._ Tincture of aconite, 1 fl. dr.; carbonate of soda, 1-1/2 dr.; sulphate of magnesia, 1-1/2 oz.; water, 6 oz. A table-spoonful when the pain is urgent. In gastralgia this should only be administered under medical supervision or advice.

=Mixture, Al′kaline.= See MIXTURE, ANTACID.

=Mixture, Al′mond.= _Syn._ EMULSION OF ALMONDS, MILK OF A.; MISTURA AMYGDALÆ (B. P., Ph. L., E., & D.), LAC AMYGDALÆ, L. _Prep._ 1. (Ph. L.) Confection of almonds, 2-1/2 oz.; distilled water, 1 pint; gradually add the water to the confection while triturating, until they are mixed; then strain the liquid through linen.

2. (Ph. E.) From almond confection, 2 oz., and water, 1 quart; as the last. Or, from sweet almonds (blanched), 10 dr.; white sugar, 5 dr.; mucilage, 1/2 fl. oz. (or powdered gum, 3 dr.); made into an emulsion with water, 1 quart.

3. (Ph. D.) Sweet almonds (blanched), 5 dr.; refined sugar, 2 dr.; powdered gum, 1 dr.; distilled water, 8 fl. oz.; as the last.

4. (B. P.) Compound powder of almonds (sweet), 1; water, 8; triturate and strain.

_Obs._ The last formula produces the article usually employed in dispensing in the shops. The addition of a little more sugar renders it more pleasant; and 2 or 3 bitter almonds, as in the formula of the Ph. D. 1826, or 1 or 2 fl. dr. of rose or orange-flower water, may occasionally be added, to diversify the flavour.——_Dose_, 2 or 3 table-spoonfuls, _ad libitum_; as a demulcent and emollient in coughs and colds, or as a vehicle for more active medicines.

=Mixture of Ammonia, Muriate of.= (Sir G. Lefevre.) _Syn._ MISTURA AMMONIÆ MURIATIS. _Prep._ Muriate of ammonia, 60 gr.; extract of liquorice, 3 dr.; tartarised antimony, 2 gr.; distilled water, 8 oz. A tablespoonful every 2 hours in pleurisy, congestion of mucous membranes, &c.

=Mixture, Ammoni′acum.= _Syn._ EMULSION OF AMMONIACUM, MILK OF A.; MISTURA AMMONIACI (B. P., Ph. L. & D.), LAC AMMONIACI, L. _Prep._ 1. (Ph. L.) Prepared ammoniacum, 5 dr.; distilled water, 1 pint; rub the ammoniacum with the water, gradually added, until they are perfectly mixed.

2. (Ph. D.) Ammoniacum, 1/4 oz.; water, 8 fl. oz.; as the last, but straining through muslin.

3. (B. P.) Ammoniacum, 1/4 oz.; rubbed down with water, 8 oz., and strain.——_Dose_, 1/2 to 1 gr.

_Obs._ The last formula produces the best and most effective mixture, owing to the use of the raw instead of the strained drug.——_Dose_, 1 to 2 table-spoonfuls, either alone or combined with squills or ipecacuanha; as an expectorant and demulcent in chronic coughs, humoral asthma, &c.

=Mixture, A′nodyne.= _Syn._ MISTURA ANODYNA, JULEPUM CALMANS, L. _Prep._ 1. Prepared chalk, 2 dr.; syrup of poppies, 1 oz.; fetid spirit of ammonia, 1-1/2 dr.; oils of dill and aniseed, of each 3 drops; water, 4-1/4 fl. oz.——_Dose._ A teaspoonful 3 or 4 times a day; in the diarrhœa and colic of infancy.

2. (P. Cod.) Syrup of opium, 2 dr.; syrup of orange flowers, 6 dr.; lettuce water, 4 fl. oz. To allay pain, induce sleep, &c. _Dose_, 1 table-spoonful.

3. (Vicat.) Ammoniated alcohol, 3/4 fl. oz.; powdered opium, 1 dr.; powdered camphor, 1/2 dr.; proof spirit, 1-1/2 fl. oz.; digest, with agitation, for 3 or 4 days, and filter. In toothache arising from caries, and as a lotion to the temples in headache.

=Mixture, Antac′id.= _Syn._ ABSORBENT MIXTURE, ALKALINE M.; MISTURA ALKALINA, M. ANTACIDA, L. _Prep._ 1. Liquor of potassa and spirit of nutmeg, of each 2 fl. dr.; tincture of rhubarb, 3 fl. dr.; tincture of opium, 1 fl. dr.; water, 5 fl. oz. In dyspepsia, heartburn, &c., accompanied with flatulence.

2. Spirit of sal volatile and orange-flower water, of each 1 fl. oz.; simple syrup, 1-1/2 fl. oz; water, 2-1/2 fl. oz. In acidity, &c., accompanied with languor and low spirits.

3. Sesquicarbonate of ammonia, 2 dr.; syrup of orange peel and tincture of gentian, of each 1 fl. oz.; water, 4 fl. oz. In dyspepsia, heartburn, &c., arising from excessive indulgence in spirituous or fermented liquors. It also possesses considerable stimulating properties, and will partially remove the fit of drunkenness.

4. (Collier.) Prepared chalk, 2 dr.; tincture of ginger, 2 fl. dr.; compound tincture of cardamoms, 1-1/2 fl. oz.; pimento water, 6 fl. oz. In diarrhœa accompanied with acidity.

5. (Collier.) Chalk mixture, 5 fl. oz.; tinctures of catechu and cinnamon, of each 1/2 fl. oz. In chronic diarrhœa.

6. (Ryan.) Liquor of potassa, 2 fl. dr.; tincture of opium, 1 fl. dr.; calcined magnesia, 1 dr.; oil of peppermint, 5 drops; lime water, 8 fl. oz. In dyspepsia accompanied with acidity, flatulence, and constipation.

=Mixture, Anticroup′al.= _Syn._ MISTURA SENEGÆ, L. _Prep._ (Jadelot.) Infusion of senega, 4 oz.; syrup of ipecacuanha, 1 oz.; oxymel of squills, 3 dr.; tartarised antimony, 1-1/2 gr.; mix. By spoonfuls, in croup.

=Mixture, Anti-eme′tic.= _Syn._ MISTURA ANTI-EMETICA, L. _Prep._ 1. Creasote, 12 drops; acetate of morphia, 1-1/2 gr.; camphor, 10 gr. rectified spirit, 1/2 fl. oz.; syrup of orange peel, 1-1/2 fl. oz.; distilled vinegar, 4 fl. oz. In sea-sickness, &c.——_Dose_, 1 table-spoonful on the approach of vomiting, and repeated at intervals of half an hour until the vomiting ceases.

2. (Dr. Barker.) Compound tincture of camphor, 1 fl. dr.; burnt brandy, 1 fl. oz.; sugar, 1/2 oz.; infusion of mint, 6 fl. oz.——_Dose_, 1/2 to 1 table-spoonful, every 1/4 hour, until the vomiting ceases.

=Mixture, Anti-epilep′tic.= _Syn._ MISTURA ANTI-EPILEPTICA, L. _Prep._ (M. Lemoine.) Liquor of ammonia, 12 drops; syrup of orange flowers, 1 oz.; distilled water of linden flowers, 2 oz.; do. of cherry laurel, 1/2 oz.; mix. According to M. Lemoine, this is a specific in epilepsy.——_Dose_, 1 table-spoonful, or more.

=Mixture, Antihyster′ic.= _Syn._ MISTURA ANTIHYSTERICA, L.; POTION ANTIHYSTERIQUE, Fr. _Prep._ (Dr Josat.) Cyanide of potassium, 1-3/4 gr.; distilled lettuce water, 4-1/2 fl. oz.; syrup of orange flowers, 1-1/2 fl. oz.——_Dose_, 1 or 2 teaspoonfuls every ten minutes, when the fit is expected; during the fit it may be given in double doses. Dr Josat declares its efficacy to have been indisputably proved in upwards of 55 cases.

2. (Magendie.) Cyanide of potassium, 2 gr.; lettuce water (distilled), 4 oz.; syrup of marshmallow, 2 oz. Resembles the last.

3. (Dr Paris.) Assafœtida, 1 dr.; peppermint water, 5 fl. oz.; make an emulsion, and add of ammoniated tincture of valerian, 2 fl. dr.; tincture of castor, 3 fl. dr.; sulphuric ether, 1-1/2 fl. dr.——_Dose_, 1 table-spoonful, 3 or 4 times a day, or oftener.

4. (P. Cod.) Syrup of wormwood, 1 oz.; tincture of castor, 1/2 dr.; valerian water and orange-flower water, of each 2 oz.; ether, 1 dr. As the last.

=Mixture, Antimo′′nial.= See MIXTURE, CONTRA-STIMULANT.

=Mixture, Antipertus′sic.= _Syn._ MISTURA ANTIPERTUSSIENS, L. _Prep._ 1. COCHINEAL (powdered), 2 dr.; carbonate of potassa, 1 dr.; boiling water, 8 fl. oz.; infuse for 1 hour, strain, and add of lump sugar, 1-1/2 oz.

2. (Dr Bird.) Extract of hemlock, 12 gr.; alum, 25 gr.; syrup of red poppies, 2 fl. dr.; dill water, 3 fl. oz.

3. (Dr Reece.) Tincture of assafœtida, 1 fl. dr.; tincture of opium, 10 or 12 drops; powdered ipecacuanha, 10 gr.; water, 2 fl. oz.——_Dose_. A teaspoonful every 3 hours, in hooping cough, for a child 2 or 3 years old, and other ages in proportion.

=Mixture, Antiscrof′ulous.= _Syn._ MISTURA ANTISCROFULOSA, L. _Prep._ From tincture of bichloride of gold, 30 drops; tincture of iodine, 40 drops; tincture of gentian, 1 fl. dr.; simple syrup, 7 fl. dr.; rose water, 5 fl. oz.——_Dose._ A dessert-spoonful, 3 or 4 times daily, in a wine-glassful of water; observing to shake the bottle before pouring out the liquid. Mr Cooley states that he has seen repeated instances of the excellent effects of this medicine in scrofula, syphilis, and various glandular diseases, even under all the disadvantages of a salt-meat diet and confinement on shipboard.

=Mixture, Antispasmod′ic.= _Syn._ MISTURA ANTISPASMODICA, L. _Prep._ 1. Tincture of castor, 6 fl. dr.; sulphuric ether and laudanum, of each 1 fl. dr.; syrup of saffron, 1 fl. oz.; cinnamon water, 4 fl. oz.

2. (Dr Collier.) Assafœtida and camphor mixtures, of each 2-1/2 fl. oz.; tincture of valerian, 1 fl. oz.

3 (P. Cod.) Lime or linden-flower water and orange-flower water, of each 2 oz.; syrup of orange flowers, 1 oz.; ether, 1/2 dr.——_Dose._ (Of each of the above) 1 to 2 table-spoonfuls.

=Mixture, Ape′′rient.= _Syn._ MISTURA APERIENS, L. _Prep._ 1. (Abernethy.) Sulphate of magnesia, 1 oz.; manna, 1/2 oz.; infusion of senna, 1-1/2 fl. oz.; tincture of senna, 1/2 fl. oz.; mint water, 2 fl. oz.; distilled water, 4 fl. oz.; mix. This is the true ‘ABERNETHY BLACK DRAUGHT,’

2. (Dr Christison.) Sulphate of magnesia, 1-1/2 oz.; water, 4 fl. oz.; dissolve, and add, of tincture of senna, 1 fl. oz.; infusion of roses, 4 fl. oz.——_Dose._ A wine-glassful hourly, until it begins to operate.

3. (Dr Collier.) Sulphate of iron, 20 gr.; Epsom salts, 1 oz.; pennyroyal water, 1 pint; dissolve.——_Dose._ A wine-glassful twice a day, in atonic amenorrhœa.

=Mixture, Aromat′ic.= _Syn._ MISTURA AROMATICA, L. _Prep._ 1. (P. Cod.) Syrup of clove gilliflowers, 1 oz.; spirit of cinnamon, 1/2 oz.; confection of hyacinth, 2 dr.; peppermint water and orange-flower water, of each 2 oz.

2. (Guy’s Hosp.) Aromatic confection (Ph. L., in powder), 3 dr.; peppermint water, 9 fl. oz. Sometimes a little tincture of calumba is added.

3. (St Barth. Hosp.) Aromatic confection, 2-1/2 dr.; water, 5 fl. oz.; pimento water, 3 fl. oz.; mix. The last two are excellent aromatic absorbents in diarrhœa, heartburn, flatulence, acidity, &c.——_Dose_, 1 or 2 table-spoonfuls every 2 or 3 hours, or as required.

=Mixture, Aromatic Iron.= Pale bark, in powder, 4; calumba, in powder, 2; cloves, bruised, 1; iron wire, 2; compound tincture of cardamoms, 12; tincture of orange peel, 2; peppermint water, 50; macerate the first four ingredients in the last one for three days, agitating occasionally, filter, add the tinctures, and make up to 50. Used as a tonic.——_Dose_, 1 to 2 oz.

=Mixture, Arsen′ical.= _Syn._ MISTURA ARSENICALIS, L. _Prep._ From liquor of arsenite of potassa——Ph. L., 2 fl. dr.; compound tincture of cardamoms, 4 fl. dr.; cinnamon water, 2 fl. oz.; pure water, 3 fl. oz.; mix.——_Dose._ A small table-spoonful, twice a day, after a full meal; in agues, periodic headaches, lepra, psoriasis, chronic rheumatism, &c. It should be exhibited with caution, and its effects watched; and after 5 or 6 days the dose should be reduced to half the quantity.

=Mixture, Astrin′gent.= _Syn._ MISTURA ASTRINGENS, L. _Prep._ 1. (Pradel.) Tannin, 12 gr.; tincture of rhatany, 1 dr.; simple syrup, 7 dr.; mucilage, 1 oz.; camphor mixture, 4 oz.

2. (A. T. Thomson.) Extract of catechu, 2 dr. (or tincture 1 oz.); cinnamon water, 8 oz.; dissolve.——_Dose_, 1 to 3 table-spoonfuls, after every liquid dejection, in diarrhœa and dysentery.

=Mixture, Atroph′ic.= _Syn._ MISTURA ATROPHICA, L.; POTION ATROPHIQUE, Fr. _Prep._ (Magendie.) Iodide of potassium, 4 dr.; lettuce water, 8 oz.; peppermint water, 2 dr.; syrup of marshmallow, 1 oz.——_Dose_, 1 tablespoonful, twice a day; in hypertrophy (enlargement) of the heart. Sometimes 1 to 2 dr. of tincture of foxglove is added to the mixture.

=Mixture, Balsamic.= (P. Cod.) _Syn._ MISTURA BALSAMICA. _Prep._ Balsam copaiba, 2 oz.; rectified spirit, 2 oz.; syrup of tolu, 2 oz.; peppermint water, 4 oz.; nitric ether, 2 dr. Mix the alcohol and ether, add the balsam, then the syrup and water.

=Mixture, Bar′ley.= _Syn._ MISTURA HORDEI, L. See DECOCTION.

=Mixture of Bismuth.= (St Th. Hosp.) _Syn._ MISTURA BISMUTHI. _Prep._ Subnitrate of bismuth, 10 gr.; compound powder of tragacanth, 5 gr.; water, 1 oz. For 1 dose.

=Mixture of Bisulphide of Carbon.= (Clarus.) _Syn._ MISTURA BISULPHURETI CARBONIS. _Prep._ Bisulphide of carbon, 20 minims; sugar, 2 dr.; milk, 6 oz.——_Dose_, 1/2 oz. 4 times a day.

=Mixture of Boracic Acid.= (Chaussier.) _Syn._ MISTURA ACIDI BORACICI. _Prep._ Camphor mixture, 4 oz.; boracic acid, 60 gr.; syrup of orange peel, 1 oz.

=Mixture of Burnt Hartshorn.= See DECOCTION, WHITE.

=Mixture, Brandy.= _Syn._ MIXTURE OF SPIRIT OF FRENCH WINE, EGG FLIP‡; MISTURA SPIRITUS VINI GALLICI (B. P., Ph. L.), L. _Prep._ 1. (Ph. L.) Brandy and cinnamon water of each 4 fl. oz.; yolks of 2 eggs; white sugar, 1/2 oz.; oil of cinnamon, 2 drops; mix. A valuable stimulant and restorative in low fevers, and in extreme exhaustion from hæmorrhages, &c.; but scarcely a fitting subject for the labours of the College of Physicians, since almost every cook and housewife could produce a better compound than the product of the College formula.

2. (B. P.) Brandy, 4 gr.; cinnamon water, 4 oz.; the yolks of 2 eggs; sugar, 1/2 oz.; mix.——_Dose_, 1/2 to 1-1/2 oz., in prostration and last stages of fever.

=Mixture of Caffein.= (Vanden-Corput.) _Syn._ MISTURA CAFFEINÆ. _Prep._ Caffein, 7 gr.; distilled water, 3 oz.; hydrochloric acid, 2 drops; syrup of orange-flower water, 1/2 oz.; mix.——_Dose_, 1 tablespoonful.

=Mixture, Cam′phor.= _Syn._ CAMPHOR JULEP, CAMPHOR WATER; MISTURA CAMPHORÆ (Ph. L. & D.), EMULSIO CAMPHORÆ (Ph. E.) MISTURA CAMPHORATA, L. _Prep._ 1. (Ph. L.) Camphor, 1/2 dr.; rectified spirit, 10 drops; triturate together, gradually adding of water, 1 pint; and strain through linen.

2. (Ph. D.) Tincture of camphor, 1 fl. oz.; distilled water, 3 pints; agitate well together, and after 24 hours filter through paper.

3. (Ph. E.) See EMULSION.

_Uses, &c._ Camphor julep is chiefly used as a vehicle for other medicines.——_Dose_, 1/2 to 1 wine-glassful.

4. (With MAGNESIA: MISTURA CAMPHORÆ CUM MAGNESIA——Ph. E. & D., AQUA CAMPHORÆ——Ph. U. S.)——_a._ (Ph. E.) Camphor, 10 gr., carbonate of magnesia, 25 gr.; triturate together, then gradually add of water, 6 fl. oz., still continuing the trituration.

_b._ (Ph. D.) Camphor, 12 gr.; carbonate of magnesia, 1/2 dr.; water, 6 fl. oz.; as last.

_c._ (Ph. U. S.) Camphor, 2 dr.; rectified spirit, 40 drops; triturate, add of carbonate of magnesia, 4 dr., and again triturate, adding, gradually, of water, 32 fl. oz. Antacid, antispasmodic, and anodyne.——_Dose_, 1 to 2 table-spoonfuls. Used without straining. It is stronger than the simple mixture.

_d._ CARBONATED CAMPHOR MIXTURE. _Syn._ MISTURA CAMPHOR CARBONICA. Water strongly charged with carbonic acid gas, agitated with powdered camphor and strained.

=Mixture, Carmin′ative.= _Syn._ MISTURA CARMINATIVA, L. _Prep._ (Dr Paris.) Calcined magnesia, 1/2 dr.; peppermint water, 2-1/2 fl. dr.; compound tincture of lavender, 1/2 fl. dr.; spirit of caraway, 4 fl. dr.; syrup of ginger, 2 fl. dr.; mix. Antacid and carminative. For 1 or 2 doses.

=Mixture of Cassia.= (Fr. Hosp.) _Syn._ MISTURA CASSIÆ, L.; EAU DE CASSE, F. Cassia pulp, 2 oz.; hot water, 1-1/2 pint. May be taken by the wineglass. Laxative.

=Mixture of Cassia, Antimoniated.= (Foy.) _Syn._ MISTURA CASSIÆ ANTIMONIATA, EAU DE CASSE. Emitisée. _Prep._ Pulp of cassia, 1 oz.; boiling water, 1-1/2 pint. Macerate, strain, and add sulphate of magnesia, 1 oz.; emetic tartar, 3 gr. By cupfuls. In painters’ colic.

=Mixture, Cathar′tic.= See MIXTURE, APERIENT, M. SENNA, &c.

=Mixture, Chalk.= _Syn._ CRETACEOUS MIXTURE; MISTURA CRETÆ (B. P.), MISTURA CRETA (Ph. L. E. & D.), M. CRETACEA, L. _Prep._ 1. (Ph. L.) Prepared chalk, 1/2 oz.; sugar, 3 dr.; mixture of acacia (mucilage), 1-1/2 fl. oz., triturate together, then add of cinnamon water, 18 fl. oz.

2. (Ph. E.) Prepared chalk, 10 dr.; white sugar, 5 dr.; mucilage, 3 fl. oz; spirit of cinnamon, 2 fl. oz.; water, 1 quart; as the last.

3. (Ph. D.) Prepared chalk, 2 dr.; syrup and mucilage, of each, 1/2 oz.; cinnamon water, 7 fl. oz.

4. (B. P.) Prepared chalk, 1; gum Arabic, in powder, 1; syrup, 2; cinnamon water, 30; mix by trituration.——_Dose_, 1 to 2 gr., with astringent tinctures and opium.

_Obs._ The above are antacid and absorbent.——_Dose_, 1 to 3 table-spoonfuls, either alone or combined with aromatic confection; in heartburn, and in diarrhœa after every liquid motion. In the latter affection, a little tincture of catechu or laudanum is often added; and when there is vomiting or nausea, either peppermint or spearmint water is generally substituted for the whole or a part of the simple water ordered in the above formulæ.

=Mixture of Chlorine.= _Syn._ MISTURA CHLORINII. Dr Watson prescribes 2 fl. dr. of the solution to 1 pint of water. The dose of the mixture is 4 fl. dr. every 3 hours, according to age, in scarlatina.

=Mixture of Chloroform.= (Ph. U. S.) _Syn._ MISTURA CHLOROFORMI. _Prep._ Chloroform, 1/2 oz. (by weight); camphor, 1 dr.; yolk of 1 egg; water, 6 oz. Rub the yolk first by itself, then with the camphor, previously dissolved in the chloroform, and lastly, with the water gradually added.

=Mixture, Cincho′na.= _Syn._ BARK MIXTURE; MISTURA CINCHONÆ, L. _Prep._ (Copland.) Confection of roses, 1/2 oz.; boiling decoction of bark, 1 fl. oz.; triturate, in 10 minutes strain, and add diluted sulphuric acid, 1-1/2 fl. dr.; spirit of nutmeg, 4 fl. dr. Febrifuge, tonic, and stomachic.——_Dose_, 1 to 3 table-spoonfuls, 2 or 3 times a day.

=Mixture of Citrate of Caffein.= _Syn._ MISTURA CAFFEINÆ CITRATIS, POTION CONTRE MIGRAINÆ. Syrup of citrate of caffein, 1 fl. oz.; water (or any agreeable diluent), 5 oz. A table-spoonful frequently.

=Mixture, Col′chicum.= _Syn._ GOUT MIXTURE; MISTURA ANTARTHRITICA, M. COLCHICI, L. _Prep._ (Sir S. Scudamore.) Magnesia, 1-1/2 dr.; vinegar of colchicum and syrup of orange peel, of each 4 fl. dr.; peppermint water, 3 fl. oz. A table-spoonful every 3 or 4 hours during the fit of gout.

=Mixture, Contra-stim′ulant.= _Syn._ MISTURA CONTRA-STIMULANS, JULEPUM C., M. ANTIMONII POTASSIO-TARTRATIS, L. _Prep._ (Laennec.) Tartar emetic, 3 gr.; infusion of orange leaves, 8 fl. oz.; syrup of do., 1 fl. oz.——_Dose._ A wine-glassful, or more, every 2 hours; in inflammation of the lungs, hooping-cough, &c.

=Mixture of Copaiba.= (Guy’s Hosp.) _Syn._ MISTURA COPAIBÆ. _Prep._ Balsam of copaiba, 3 dr.; solution of carbonate of potash, 1-1/2 dr. Rub together and gradually add decoction of barley, 8 oz.; spirit of nitric ether, 3 dr.——_Dose_, 1 oz. 3 times a day. See MIXTURES, BALSAMIC.

=Mixture, Cough.= _Syn._ MISTURA BECHICA, L. _Prep._ 1. Almond mixture, 4 fl. oz.; oxymel of squills, 1 fl. oz.; ipecacuanha wine and syrup of tolu, of each 1/2 fl. oz.

2. Tincture of tolu, 1/8 fl. oz.; paregoric elixir and tincture of squills, of each 1 fl. oz.; syrup of poppies, 3 fl. oz.; water, 3-1/2 fl. oz.

3. Mixture of ammoniacum, 4 fl. oz.; syrup of squills, 2 fl. oz. In the coughs of old persons.

4. Antimonial wine, 3 fl. dr.; syrup of poppies, 1-1/2 fl. oz.; water, 4 fl. oz. In dry, husky coughs.——_Dose_ (of each of the above), 1 table-spoonful, 2 or 3 times a day, or oftener.

5. (Dr Monro.) Paregoric, 1/2 fl. oz.; sulphuric ether and tincture of tolu, of each 1/4 oz.——_Dose._ A teaspoonful in water, night and morning, or when the cough is troublesome.

6. (Dr Radcliff.) Syrup of poppies, syrup of squills, and paregoric, equal parts.——_Dose._ As the last. In all cases the bowels should be kept gently moved by some mild aperient.

7. (Dr Wood’s Brown Mixture.) Extract of liquorice, 2 dr.; powdered gum Arabic, 2 dr.; boiling water, 4 oz.; dissolve, and add antimonial wine, 2 dr.; laudanum, 20 minims.——_Dose._ A table-spoonful occasionally. A popular American remedy.

=Mixture, Cre′asote.= _Syn._ MISTURA CREASOTI, M. CREAZOTI (B. P., Ph. E.), L. _Prep._ 1. (Ph. E.) Creasote and acetic acid, of each 16 drops; mix, then add of compound spirit of juniper and syrup, of each 1 fl. oz.; water, 14 fl. oz.; and agitate well together.——_Dose_, 1/2 to 1 wine-glassful, in nausea and vomiting, especially to prevent or relieve sea-sickness.

2. (B. P.) Creasote, 16 minims; glacial acetic acid, 16 minims; spirit of juniper, 1/2 dr.; syrup, 1 oz.; distilled water, 15 oz.; mix.——1 to 2 oz.

=Mixture of Cubebs.= _Syn._ MISTURA CUBEBÆ. Powder of cubebs, 1 oz.; sugar, 2 dr.; mucilage, 2 oz.; cinnamon water, 6 oz.——_Dose_, 1/2 oz. to 1 oz.

=Mixture, Demul′cent.= Syn. MISTURA DEMULCENS, L. See ALMOND MIXTURE, GUM M., &c.

=Mixture, Diaphoret′ic.= _Syn._ MISTURA DIAPHORETICA, L. _Prep._ 1. Solution of acetate of ammonia, 3 fl. oz.; antimonial wine, 2 fl. dr.; tincture of henbane, 1-1/2 fl. dr.; camphor mixture, 3 fl. oz.——_Dose_, 1 table-spoonful every 3 or 4 hours; in fevers, &c.

2. To the last add of sweet spirit of nitre, 1/2 fl. oz. As above.

=Mixture for Diarrhœa.= (Board of Health.) _Syn._ MISTURA PRO DIARRHŒA. Aromatic powder, 3 dr.; compound spirits of ammonia, 3 dr.; tincture of catechu, 10 dr.; compound tincture of cardamoms, 6 dr.; tincture of opium, 1 dr.; chalk mixture to make 20 oz.——_Dose._ For an adult, 1 oz.; for a child of 12 years of age, 1/2 oz.; for 7 years, 1/4 oz.; after each liquid stool.

=Mixture, Diarrhœ′a.= See MIXTURE, CHALK, &c.

=Mixture, Diuret′ic= _Syn._ MISTURA DIURETICA, L. _Prep._ 1. Nitrate of potassa, 2 dr.; sweet spirit of nitre, 3 fl. dr.; syrup of squills, 1-1/2 fl. oz.; peppermint water, 4 fl. oz.

2. (A. T. Thomson.) Infusion of foxglove, 5-1/2 fl. oz.; tincture of foxglove, 1/2 fl. dr.; acetate of potassa, 2 dr.; spirit of juniper, 1/2 fl. oz.; tincture of opium, 1/2 fl. In dropsy.——_Dose_, 1 to 2 table-spoonfuls, every 2 or 3 hours. The last must be used with caution.

=Mixture, Effervescing.= (P. Cod.) _Syn._ MISTURA EFFERVESCENS; POTION GAZEUSE DE RIVIÈRE. _Prep._ Dissolve 1/2 dr. of bicarbonate of potash in 2 oz. of water, and add 4 dr. of syrup. Mix also 1/2 dr. of citric acid with 1/3 oz. of syrup of citric acid and 2 oz. of water. Mix an equal quantity of each, and give it while effervescing.

=Mixture of Elaterium.= (Dr Ferriar.) _Syn._ MISTURA ELATERII. _Prep._ Elaterium, 1 gr.; spirit of nitric ether, 2 fl. oz.; tincture of squills, 1/2 oz.; oxymel of colchicum, 1/2 oz.; syrup of buckthorn, 1 fl. oz.——_Dose_, 1 dr. 3 times a day in water.

=Mixture, Emet′ic.= _Syn._ MISTURA EMETICA, L. _Prep._ 1. (Copland.) Sulphate of zinc, 40 gr.; ipecacuanha wine and tincture of serpentary, of each 4 fl. dr.; tincture of capsicum, 40 drops; oil of chamomile, 12 drops; peppermint water, 4-1/2 fl. oz. As an excitant emetic; in cases of poisoning by narcotics, &c.

2. (Magendie.) Coloured emetine, 4 gr. (or white emetine, 1 gr.); acetic acid, 8 drops; mix, and add of infusion of orange leaves or lime flowers, 3-1/2 fl. oz.; syrup of marshmallows, 1 fl. oz.

3. (A. T. Thomson.) Ipecacuanha, 1/2 dr.; tartar emetic, 1 gr.; tincture of squills, 1 fl. dr.; water, 6 fl. oz. _Dose_, 1 to 2 table-spoonfuls, followed by half the quantity every 10 or 15 minutes, until vomiting is produced; at the same time assisting the action of the medicine by drinking copiously of warm water.

=Mixture, Emmen′agogue.= See MIXTURE, STEEL, &c.

=Mixture, Expec′torant.= _Syn._ MISTURA EXPECTORANS, L. _Prep._ 1. (Collier.) Oxymel of squills and mucilage, of each 1 oz.; syrup of marshmallows, 2 oz.; camphor julep, 3 fl. oz.——_Dose_, 1 to 2 table-spoonfuls, 2 or 3 times a day; in coughs, hoarseness, asthma, &c.

2. (A. T. Thomson.) Almond mixture, 5 fl. oz.; ipecacuanha wine and tincture of squills, of each 1 fl. dr.; syrup of tolu, 6 fl. dr.——_Dose_, 1 table-spoonful; in humoral asthma, catarrh, &c., when the cough is urgent.

=Mixture, Feb′rifuge.= _Syn._ MISTURA FEBRIFUGA, L. See ACETATE OF AMMONIA MIXTURE, DIAPHORETIC M., &c.

=Mixture of Gentian.= (Ph. B.) _Syn._ MISTURA GENTIANÆ. _Prep._ Macerate gentian root, sliced, 1/4 oz.; bitter orange peel, cut small, and coriander fruit, bruised, of each 30 gr., in proof spirit, 2 fl. oz., for 2 hours. Add distilled water, 8 fl. oz.; macerate again for 2 hours, and strain through calico.——_Dose_, 1 oz.

=Mixture, Gentian (Compound).= Gentian, bruised, 1-1/2; bitter orange peel, bruised, 3/4; cardamom seeds, bruised, 1/4; proof spirit, 20: macerate for forty-eight hours with 15 of the spirit, agitating occasionally, pack in a percolator, let it drain, and then pour on the remaining spirit; when it ceases to drop, wash the marc with spirit to make up 20.——_Dose_, 1 to 2 drachms.

=Mixture, Gregory’s.= See POWDERS.

=Mixture, Griffith’s.= See MIXTURE, STEEL.

=Mixture, Guai′acum.= _Syn._ EMULSION OF GUAIACUM, MILI OF G.; MISTURA GUAIACI (B. P.), (Ph. L. & E.), LAC G., L. _Prep._ (Ph. L.) Gum guaiacum, 3 dr.; white sugar, 1/2 oz.; gum acacia, 2 dr. (all in powder); triturate together, and to these, whilst rubbing, gradually add of cinnamon water, 1 pint.

2. (Ph. E.) Guaiacum, 3 dr.; sugar, 1/2 oz.; mucilage, 1/2 fl. oz.; cinnamon water, 19-1/2 fl. oz.; as before.——_Dose_, 1 to 3 table-spoonfuls, 2 or 3 times a day; in chronic rheumatism, gout, &c.

3. (B. P.) Guaiac resin, in powder, 2; sugar, 2; gum Arabic, in powder, 1; cinnamon water, 80; triturate, adding the cinnamon water gradually.——_Dose_, 1/2 to 2 oz.

=Mixture, Gum.= _Syn._ MUCILAGE; MISTURA ACACIÆ (Ph. L.), MUCILAGO (Ph. E.), MUCILAGO ACACIÆ (Ph. D.), MUCILAGO ARABICI GUMMI, L. _Prep._ 1. (Ph. L.) Gum acacia (in powder), 13 oz.; boiling distilled water, 1 pint; rub the gum with the water, gradually poured in, until solution is complete.

2. (Ph. E.) Gum, 9 oz.; cold water, 1 pint; macerate, with occasional stirring, until dissolved, then strain through linen or calico.

3. (Ph. D.) Gum (coarsely powdered), 4 oz.; water (cold), 6 fl. oz.; dissolve, and strain through flannel.

_Uses, &c._ Mucilage of gum acacia is chiefly employed to render oily and resinous substances miscible with water. “Oils require about 3/4 their weight; balsams and spermaceti, equal parts; resins, 2 parts; and musk, 5 times its weight,” for this purpose. (Montgomery.) The GUM MIXTURE, Ph. E., will be found under ‘EMULSION,’

=Mixture of Hemidesmus.= (Mid. Hosp.) _Syn._ MISTURA HEMIDESMI. _Prep._ Bruised root of hemidesmus, 10 oz.; extract of liquorice, 10 gr.; distilled water, 10 oz. Digest for 12 hours, heat the strained liquor to 180° F., and strain again.——_Dose_, 1/3 part 3 times a day.

=Mixture of Hemlock, Compound.= (Guy’s Hosp.) _Syn._ MISTURA CONII COMPOSITA. _Prep._ Extract of hemlock, 1 dr.; carbonate of soda, 1-1/2 dr.; decoction of liquorice, 11 oz.; spirit of pimento, 6 dr.——_Dose_, 1 oz. to 2 oz. Myrrh mixture is sometimes substituted for decoction of liquorice.

=Mixture of Horseradish, Compound.= (Dr Paris.) _Syn._ MISTURA ARMORACIÆ COMPOSITA. _Prep._ Horseradish root, 1/2 oz.; mustard seed, 1/2 oz.; boiling water, 1 pint. Macerate for an hour, and to 7 oz. of the strained infusion add aromatic spirit of ammonia, 1 fl. dr.; spirit of pimento, 1/2 oz. In paralysis.

=Mixture, Hydrocyan′ic.= _Syn._ MIXTURE OF PRUSSIC ACID; MISTURA ACIDI HYDROCYANICI, L. _Prep._ From medicinal prussic acid, 15 drops; simple syrup (pure), 1 fl. oz.; distilled water, 5 fl. oz.;——_Dose_, 1 table-spoonful, 2 or 3 times daily. Each dose contains 1-1/4 drop of medicinal prussic acid. The bottle should be shaken before pouring out the dose. Magendie’s formulæ for this mixture are omitted, because the acid which he orders is not kept in the shops in England.

=Mixture of Iodine with Sarsaparilla.= (Magendie.) _Syn._ MISTURA IODINII CUM SARZA. _Prep._ Decoction of sarsaparilla, 1-1/2 pint; iodide of potassium, 1 dr.; syrup of orange, 2 oz.

=Mixture, I′ron.= See MIXTURE, STEEL.

=Mixture, I′ron (Compound).= See MIXTURE, STEEL.

=Mixture, Marshmallow.= _Syn._ MISTURA ALTHÆÆ (Ph. E.), L. _Prep._ (Ph. E.) Marshmallow root (dried), 4 oz.; stoned raisins, 2 oz.; water, 5 pints; boil to 3 pints, strain through linen, and after the sediment has subsided, decant the clear portion.

2. (Ph. D.) See DECOCTION. Demulcent.——_Dose._ A few spoonfuls _ad libitum_, so as to take 1 to 3 pints in the 24 hours; in strangury, calculus, coughs, fevers, &c.

=Mixture of Monesia.= (Neligan.) _Syn._ MISTURA MONESIÆ. _Prep._ Extract of monesia, 2 scruples; water, 7-1/2 oz.; compound tincture of cardamoms, 1/2{?} oz.

=Mixture of Musk.= (Ph. L.) _Syn._ MISTURA MOSCHI. _Prep._ Musk, 3 dr.; triturate it with white sugar, 3 dr.; gum acacia, 3 dr.; and gradually add rose water, 1 pint.——_Dose_, 1 to 2 oz.

=Mixture of Musk-seed.= (Dr Reece.) _Syn._ MISTURA ABELMOSCHI. _Prep._ Tincture of musk-seeds, 1 oz.; aromatic spirit of ammonia, 3 fl. dr.; compound spirit of lavender, 4 fl. dr.; camphor mixture, 6 oz.——_Dose_, 1/2 oz. to 1 oz.

=Mixture, Myrrh.= _Syn._ EMULSION OF MYRRH; MISTURA MYRRHÆ, L. _Prep._ (Copland.) Myrrh, 1-1/2 dr.; add to it gradually, triturating all the time, decoction of liquorice, 6 fl. oz., and strain.——_Dose_, 1 to 2 table-spoonfuls, twice or thrice a day, combined with carbonate of soda, dilute hydrochloric acid, or paregoric; in debility, and diseases of the digestive organs.

=Mixture, Narcot′ic.= _Syn._ MISTURA NARCOTICA, M. FEBRIFUGA, L. _Prep._ 1. Tincture of henbane, 2 fl. dr.; solution of acetate of ammonia, 3 fl. oz.; water, 2-3/4 fl. oz.; mix.——_Dose_, 1 to 2 table-spoonfuls, to relieve pain, procure sleep in fevers, &c.

2. (W. Cooley.) Laudanum, 1-1/2 fl. dr.; syrup of poppies, sulphuric ether, and spirit of cinnamon, of each 1 oz.; tincture of henbane, 2-1/2 fl. dr.; tincture of capsicum, 4 fl. dr.; water 2 fl. oz.——_Dose_, 1 to 2 table-spoonfuls, at the commencement of the hot fit of ague.

=Mixture, Oleo-balsam′ic.= _Syn._ MISTURA OLEO-BALSAMICA, L. _Prep._ (Hamb. Cod.) Oils of cedrat, cinnamon, cloves, lavender, mace, and marjoram, of each 20 drops; oil of rue, 10 drops; balsam of Peru, 1/2 dr.; rectified spirit, 10 oz.; digest and filter.

=Mixture of Oxalic Acid.= (Nardo.) _Syn._ MISTURA ACIDI OXALICI. _Prep._ Oxalic acid, 8 gr.; mucilage, 3 oz.; syrup, 1 oz. In inflammation, of the fauces and digestive tube.

=Mixture of Phosphorus.= (Soubeiran.) _Syn._ MISTURA PHOSPHORICI. _Prep._ Phosphorated oil, 2 dr.; powdered gum acacia, 2 dr.; peppermint water, 3 oz.; syrup, 2 oz. Mix the gum with 10 dr. of water, and thin with the oil, and gradually add the others. Contains 1 gr. of phosphorus.——_Dose_, 1/2 fl. oz.

=Mixture of Platinum Chloride.= (Hoeffer.) _Syn._ MISTURA PLATINI CHLORIDI. _Prep._ Perchloride of platinum, 1-1/2 gr.; gum juleps, 6 oz.

=Mixture of Potassium Iodide.= (Cazenave.) _Syn._ MISTURA POTASSII IODIDI. _Prep._ Iodide of potassium, 2 dr.; distilled water, 16 oz.; syrup, 2 fl. oz. 2 or 3 table-spoonfuls per diem.

=Mixture, Pur′gative.= _Syn._ MISTURA CATHARTICA, M. LAXATIVA, M. PURGANS. L. _Prep._ 1. From any of the purging salts (Epsom, Glauber, tasteless, &c.), 2 oz.; infusion of senna, 5 fl. oz.; syrup of orange peel, 1 fl. oz.; tincture of ginger, 1/2 fl. oz.; spirit of pimento, 2 fl. dr.; mix.——_Dose_, 1 to 3 table-spoonfuls, early in the morning; as an aperient in stomach complaints, &c.

2. (Dr Copland.) Manna, 1-1/2 oz.; cream of tartar, 1/2 oz.; whey, 1 quart. By wine-glassfuls, as an aperient drink, in fevers, &c.

3. (Corvisart.) Borotartrate of potassa (soluble tartar), 1 oz.; tartar emetic, 1/2 gr.; sugar, 2 oz.; water, 1-1/2 pint; dissolve. By wine-glassfuls, until it begins to operate. This has been called ‘NAPOLEON’S MEDICINE,’ from its having been frequently taken by Napoleon I. See MIXTURES OF SCAMMONY, SENNA, &c.

=Mixture of Quinine and Coffee.= _Syn._ MISTURA QUINIÆ ET CAFFEÆ; CAFÉ QUININE. Prepare 5 oz. of infusion from 4 dr. of ground coffee by percolation, and add 24 gr. of neutral sulphate of quinine and 4 dr. of sugar.——_Dose._ A tablespoonful. The coffee conceals the bitterness of the quinine.

=Mixture of Quinine with Iron.= _Syn._ MISTURA QUINIÆ CUM FERRO. Sulphate of quinine, 1 gr.; sulphate of iron, 2 gr.; dilute sulphuric acid, 5 minims; water, 1 oz. For 1 dose.

=Mixture of Rhubarb with Magnesia.= (St Thom. Hosp.) _Syn._ MISTURA RHEI CUM MAGNESIA. _Prep._ Rhubarb, 7-1/2 gr.; carbonate of magnesia, 15 gr.; peppermint water, 1-1/2 oz. For 1 dose.

=Mixture, Saline.= _Syn._ MISTURA SALINA, L. See DRAUGHT and LEMONADE.

=Mixture, Scam′mony.= _Syn._ SCAMMONY MILK; MISTURA SCAMMONII (B. P.), L. _Prep._ 1. (Ph. E.) Resin of scammony, 7 gr.; unskimmed milk, 3 fl. oz.: gradually mix, triturating all the time, so as to form an emulsion. Purgative.——_Dose._ One half.

2. (Planche’s PURGATIVE POTION.) To the last add of white sugar, 1/4 oz.; cherry-laurel (or bitter-almond) water, 4 or 5 drops. The above are the most tasteless and pleasant purgatives of an active character known.

3. (B. P.) Resin of scammony, 4 gr.; fresh milk, 2 oz.; triturate and form an emulsion.——_Dose._ The quantity of the formula for an adult, half for a child.

=Mixture, Senega, with Ammonia.= (St Th. H.) _Syn._ MISTURA SENEGÆ CUM AMMONIA. _Prep._ Infusion of senega, 1 oz.; carbonate of ammonia, 4 gr. For 1 dose.

=Mixture, Sen′na (Compound).= _Syn._ BLACK DRAUGHT, ABERNETHY’S D., CATHARTIC MIXTURE; MISTURA SENNÆ COMPOSITA (B. P.), L. _Prep._ 1. Infusion of senna, 3/4 pint; tincture of senna, 1-1/2 fl. oz.; Epsom salts, 4 oz.; carbonate of ammonia, 1/2 dr.; sugar, 3 oz.; agitate until the solids are dissolved.

2. Senna, 13 oz.; boiling water, 2 quarts; digest for 4 hours in a hot place, then press out the liquor in a tincture press, and add, of compound tincture of senna, 3/4 pint; Epsom salts, 1 lb.

3. East India senna, 2 lbs.; boiling water, 9 quarts; tincture of senna and Epsom salts, of each 3-1/4 lbs.; as the last.

4. Senna, 8 lbs.; boiling water, 9 galls.; Epsom salts, 16 lbs.; tincture of senna, 1-1/2 galls.; treacle and colouring, of each 1 quart.

5. (Guy’s Hosp.) Senna and mint, of each 1-1/4 oz. (say 1-1/2 oz.); boiling water, 1 quart; Epsom salts, 7-1/2 oz. (say 1/2 lb.).

6. (Redwood.) Infusion of senna, 18 oz.; tincture of senna, 3 oz.; sulphate of magnesia, 6 oz.; extract of liquorice and spirit of sal volatile, of each 3/4 oz.; oil of cloves, 6 drops.

7. (B. P.) Infusion of senna, 14; sulphate of magnesia, 4; extract of liquorice, 1/2; tincture of senna, 2-1/2; compound tincture of cardamoms, 1-1/4: dissolve and mix.——_Dose_, 1 to 1-1/2 oz.

_Obs._ As the above mixture contains very little spirit, and from its great consumption being made in large quantities at a time, it frequently spoils before the whole is sold especially in hot weather. To avoid this, 1-1/2 dr. of cloves, and 3 dr. of mustard seed, both bruised, may be added to every gall. of the strained liquor at the same time with the salts, spirit, and colouring, after which it must be shaken up repeatedly for a few days, and then allowed to repose for a few days more when it will become quite clear. It may be filtered through a flannel bag, but there is much loss and delay, owing to the consistence of the liquid. It is purgative in doses of 1 to 1-1/2 fl. oz.

It is a singular circumstance, that although an enormous quantity of this preparation is consumed in these countries, there is no standard formula for it in the British Pharmacopœias. See MIXTURE, APERIENT, &c.

=Mixture, Steel.= _Syn._ MISTURA FERRI COMPOSITA (B. P.), MISTURA CHALYBEATA, L. Two compounds of this class are officinal:——

1. (GRIFFITH’S MIXTURE, COMPOUND IRON M.; MISTURA FERRI, M. F. PROTOXYDI, M. F. COMPOSITA——Ph. L. E. & D.) _Prep._——_a._ (Ph. L. & E.) Carbonate of potassa, 1 dr.; powdered myrrh, 2 dr.; spirit of nutmeg, 1 fl. oz.; triturate together, and whilst rubbing, add gradually, of sugar, 2 dr.; rose water, 18 fl. oz.; mix well; then add of sulphate of iron (powdered), 50 gr.; and place it at once in a bottle, which must be kept closely corked.

_b._ (Ph. D.) Powdered myrrh and sugar, of each 1 dr.; carbonate of potassa, 1/2 dr.; essence of nutmeg, 1 fl. dr.; rose water, 7 fl. oz.; sulphate of iron, 1/2 dr.; (dissolved in) rose water, 1 fl. oz.;——_Dose_, 1 to 2 oz., 3 or 4 times a day, as a mild and genial chalybeate tonic and stimulant; in amenorrhœa, chlorosis, debility, &c., when there is no determination of blood to the head.

2. (HEBERDEN’S MIXTURE, H.’S INK; ATRAMENTUM HEBERDII; MISTURA FERRI AROMATICA——Ph. D.) Pale cinchona bark, 1 oz.; calumba root, 3 dr. (both in coarse powder;) cloves (bruised), 2 dr.; iron filings, 1/2 oz.; peppermint water, 16 fl. oz.; digest in a close vessel for 3 days, agitating frequently, then strain, and add of tincture of cardamoms (comp.), 3 fl. oz.; tincture of orange peel, 3 fl. dr. Bitter, stomachic, and aromatic.——_Dose_, 1 or 2 table-spoonfuls, or more, 3 or 4 times a day. It is very slightly chalybeated. See also MIXTURE, AROMATIC IRON.

3. Sulphate of iron, 25 gr.; carbonate of potash, 30 gr.; myrrh, 60 gr.; sugar, 60 gr.; spirit of nutmegs, 4 dr.; rose water, 9-1/2 oz. Reduce the myrrh to powder, add the carbonate of potash of sugar, and triturate them with a small quantity of rose water so as to form a thin paste, then gradually add more rose water, and the spirit of nutmegs, continuing the trituration and further addition of rose water until about eight fluid ounces of milky liquid is formed, then add the sulphate of iron previously dissolved in the remainder of the rose water and cork the bottle immediately.——_Dose_, 1 to 2 oz. as a stimulating tonic.

=Mixture of Sulphuric Acid.= (Ph. G.) _Syn._ MISTURA ACIDI SULPHURICI; HALLER’S ELIXIR. _Prep._ To 3 oz. (by weight) of rectified spirit add gradually 1 oz. (by weight) of pure sulphuric acid.——_Dose_, 5 to 20 drops diluted.

=Mixture, Ton′ic.= _Syn._ STRENGTHENING MIXTURE; MISTURA TONICA, L. _Prep._ 1. Infusion of cascarilla, 5 fl. oz.; tincture of orange peel, 7 fl. dr.; aromatic sulphuric acid, 2 fl. dr.

2. (Collier.) Decoction of bark, 5-1/2 fl. oz.; tincture of do., 3 fl. dr.; aromatic confection, 20 gr.; aromatic spirit of ammonia, 1 fl. dr.

3. (Thomson.) Infusion of calumba, 5-1/2 fl. oz.; compound tincture of cinnamon and syrup of orange peel, of each 2 fl. dr.——_Dose_, 1 to 3 table-spoonfuls, 2 or 3 times a day; in debility of the digestive organs, loss of appetite, to check nausea and vomiting, &c.

=Mixture of Wine.= (Guy’s Hosp.) _Syn._ MISTURA VINI. White wine, 6 fl. oz.; yolks of 2 eggs; sugar, 1/2 oz.; oil of cinnamon, 3 drops.——_Dose_, 1 oz.

=Mixture, Worm.= _Syn._ MISTURA ANTHELMINTICA, M. VERMIFUGA, L. _Prep._ 1. (Collier.) Sulphate of iron, 20 gr.; infusion of quassia, 8 fl. oz.——_Dose._ Two table-spoonfuls every morning fasting.

2. (Copland.) Valerian, 2 dr.; worm-seed, 4 dr.; boiling water, 8 fl. oz.; macerate 1 hour, strain, and add of assafœtida, 1 dr., previously triturated with the yolk of one egg. As the last.

3. (Richard.) Root of male fern, 1 oz.; water, 9 fl. oz.; boil to 6 fl. oz., strain, and add, of sulphuric ether, 1 dr.; syrup of tansy, 1 fl. oz. In tapeworm; as above.

=Mixture, Zinc.= _Syn._ MISTURA ZINCI, M. Z. SULPHATIS, L. _Prep._ (Collier.) Sulphate of zinc, 5 gr.; sulphate of quinine, 10 gr.; compound infusion of roses, 2 fl. oz. Tonic.——_Dose._ A teaspoonful 2 or 3 times a day, in a glass of water. Said to be very efficacious in the cure of coughs of a spasmodic character.

=MIXTURES (Arithmetic of).= The constantly recurring necessity in business and chemical manipulations of determining the value of mixtures, and of producing articles and preparations of different strengths or prices to those already in stock, has rendered a ready means of making such calculations an indispensable qualification in almost every department of trade and industrial art. As we address ourselves to the intelligent operative and busy tradesman, as well as to those more blessed by education and leisure, we feel we are bestowing a boon on many of our readers in giving a short, but sufficient, outline of this useful branch of commercial arithmetic, which is most intimately connected with the objects of the present work.

1. To determine the price of a mixture from the value and quantity of each ingredient of which it is composed.——RULE. Divide the ‘gross value’ by the ‘gross saleable’ or ‘useful quantity,’ the quotient is the value or cost per gallon, pound, &c., as the case may be.——_Example._ Required, the value per gallon of a hogshead of wine containing——

_s._ _d._ £ _s._ _d._

30 gallons @ 10 6 = 15 15 0 20 ” ” 12 6 = 12 10 0 13 ” ” 14 6 = 9 8 6 —— --------------- 63 divide into 37 13 6 --------------- Cost per gallon 0 11 11-1/2

2. To determine the proportions of substances or articles of different values or strengths which must be taken to prepare a mixture of any other value or strength.——RULE. Arrange the ‘prices’ or ‘strengths of the ingredients’ in a column, and link them together in pairs; each of those above the required price being always connected with another below it. Then set the difference between the required price and these numbers, alternately against those they are linked to; when they will indicate the quantities to be taken, as in the following examples:——_a._ Required the proportions of tea at 3_s._, 4_s._, 6_s._, and 7_s._, that must be taken to produce a mixture 5_s._ the pound. Here——

{ 3——+ 1, or 1 lb. @ 3_s._ { 4——|——+ 2, ” 2 ” ” 4_s._ 5 { 6——+ | 2, ” 2 ” ” 6_s._ { 7-----+ 1, ” 1 ” ” 7_s._

_b._ (When the number of the ingredients or prices is odd.) Required the proportions of teas at 3_s._, 5_s._, and 6_s._, the pound, to sell at 4_s._ Here the odd number must be taken a second time:——

{ 3——+——+ 1 + 2 or 3 lbs @ 3_s._ 4 { 5——+ | 1, ” 1 ” ” 6_s._ { 6-----+ 1, ” 1 ” ” 6_s._

_c._ (When the number of the ingredients is not merely odd, but the prices are unequally distributed either above or below the required price.) A dealer having wines of the same name at 7_s._, 9_s._, 11_s._, 12_s._, and 14_s._, per gallon, wishes to produce a mixture of them worth 10_s._ per gallon:——

{ 7——+---+ 1 + 4, or 5 galls. @ 7_s._ { 9——+-+ | 2, ” 2 ” ” 9_s._ 10 { 11——+ | | 3, ” 3 ” ” 11_s._ { 12----+ | 1, ” 1 ” ” 12_s._ { 14------+ 3, ” 3 ” ” 14_s._

It will be seen that by varying the manner of linking the numbers, different answers may often be obtained to the same question. It also often happens that the dealer or operator desires to use a given quantity of one particular article, or to produce a certain quantity only of the mixture instead of those indicated by the above calculations. In these instances he has simply to apply the common rule of ‘practice’ or the ‘rule of three,’ as the particular case may demand.

In the above manner the proportions of the constituents of a compound may be determined from their specific gravity, when no change of volume has arisen from their admixture; but when this is the case, as in alloys, alcoholic mixtures, &c., it is either quite inapplicable or the results obtained are mere approximations to the truth. It may, however, be conveniently employed for calculations connected with the ‘mixing’ and ‘reduction’ of spirits and other liquids, by substituting their per-centage value in ‘proof gallons’ or other corresponding denomination, for the prices in the above examples; water, when introduced be reckoned, =0. Thus:——A spirit merchant having two puncheons of rum of the strengths of 17 and 21 o. p., wishes to know what proportions of each and of water he must take to form a spirit 10 u. up. The proof value of 100 gallons of these spirits are respectively equal to 121, 117, 90, and 0 (water). Therefore——

| 0----+ 27 + 31, or 58 g. water. 90 | 117——| | 90, ” 90 ” rum @ 117 o.p. | 121----+ 90, ” 90 ” rum ” 121 ”

Suppose the dealer required to use different proportions of the spirits referred to, instead of equal measures, he has only to take such aliquot parts of the quantities thus found referring to the smaller proportion; or such multiples of those referring to the larger one, as he wishes them to bear to each in the new mixture. Numerous other applications of this rule will occur to the ingenious reader.

Questions in ‘alligation,’ as the department of arithmetic above referred to is called, are very easily resolved by the ‘method of indeterminate analysis,’ even by persons but slightly conversant with rudimentary algebra; of which, indeed, they form a simple class of problems, often admitting of an almost indefinite number of solutions.

=MO′HAIR.= The hair of a goat indigenous in Asia Minor. It is dyed and manufactured by similar materials and in a similar manner to wool.

=MOIL.= See CIDER.

=MOIRÉE METALLIQUE.= [Fr.] A beautiful crystalline appearance produced on the surface of tin plate by acids. The tin plate is submitted for a few seconds, whilst gently heated, to the action of dilute aqua regia, by which it acquires a variegated primrose appearance. It is afterwards washed in hot water, dried, and lacquered. The degree of heat and dilution of the acid modifies the beauty and character of the surface. The effect is also varied by employing dilute sulphuric acid, either alone or mixed with a portion of nitric or hydrochloric acid; or by using a solution of citric acid or caustic potassa. According to Herberger, the best metal for the purpose is plate iron, which has been coated by dipping it into a tin bath composed of pure tin, 200 parts; copper, 3 parts; arsenic, 1 part. The varnish should consist of copal in highly rectified spirit. Moirée metallique is in much less demand now than formerly.

=MO′LASSES.= See TREACLE.

=MOLES.= The small, soft excrescences and discolorations of the skin which are popularly known under this name may, when slight, be removed by touching them every day with a little concentrated acetic acid, by means of a hair pencil, observing due care to prevent the application from spreading to the surrounding parts. This does not discolour the skin. The application of lunar caustic is also very effective, but it turns the spot temporarily black. In the pure mole there is always a considerable production of hair. When other means fail, they may be easily and safely removed by surgical means. The operation is trifling; and when judiciously performed no trace of such a proceeding is left behind.

=MOLUC′CA BALM.= See LIQUEUR.

=MOLYBDATE OF AMMONIUM.= (NH_{4})_{2} MoO_{4}. _Syn._ MOLYBDENIC ACID, PEROXIDE OF MOLYBDENUM; ACIDUM MOLYBDICUM, L. _Prep._ Native sulphide of molybdenum, after being well roasted, is reduced to fine powder, digested with ammonia, and the mixture filtered, and the filtrate evaporated to dryness; the residue, molybdate of ammonium, is then dissolved in water, purified by crystallisation; and, lastly, decomposed by heat.

_Prop., &c._ Small white scales, soluble in 570 parts of water; the solution reddens litmus paper; dissolves in the alkalies, forming alkaline molybdates, from which it is again precipitated by strong acids. It is used in the preparation of molybdenum blue, and in calico-printing, but its scarcity precludes its extensive employment in the arts. Molybdate of ammonium is the salt principally used in dyeing. Silks and cottons passed through a solution of this salt, then through a bath soured with hydrochloric acid, and, lastly (without washing), through another of protochloride of tin, are dyed of a rich and permanent blue colour. A solution of molybdate of ammonia in excess of nitric acid forms a valuable agent as a test for phosphates, with which it gives a beautiful yellow precipitate (phospho-molybdate of ammonia). See PHOSPHORIC ACID.

=MOLYB′DENUM.= Mo. A very rare metal, having a white colour, discovered by Hielm in 1782.

_Prep._ By exposing molybdic acid, mixed with charcoal and placed in a covered crucible, to the strongest heat of a smith’s forge.

_Prop., &c._ It is brittle and very infusible; when heated in contact with the air, it is converted into molybdic anhydride, MoO_{3}.

=MOMOR′DICINE.= See ELATERIN.

=MOMRAUGHAN FOR HARNESS, &c.= A correspondent of the ‘Field’ newspaper gives the following formulæ for momraughan, a substance used in India for preserving saddles and every description of leather. It is made as follows:——1 lb. white wax, 3 lb. mutton fat, 1 pint spirits of turpentine; melt, and mix well together while liquid. The saddle or leather should be rubbed well with a lime in the sun, then scrubbed with a brush with soap and water; when thoroughly dry, rub it well with the momraughan (letting it soak in) in the sun. One tablespoonful will be enough for a saddle. Another recipe is:——1 pint neats-foot oil, 2 oz. beeswax, 2 oz. spirits of turpentine, other directions as above. This latter mixture, with the addition of 1 oz. Burgundy pitch, makes a very good waterproof composition for boots.

=MONE′SIA.= _Syn._ MONESIA BARK, BURANHEIM B.; CORTEX MONESIÆ, L. The bark of _Chrysophyllum Buranheim_, a tree growing in the Brazils. The rough, imported extract of this drug also commonly passes under the name of MONESIA. It is astringent, and possesses no advantage over rhatany or catechu.——_Dose_ (of the latter), 18 to 20 gr.

=MONE′SIN.= A peculiar acrid principle, analogous to saponin, found in monesia bark, to the extent of 4·7%.

=MONOBROMATED CAMPHOR.= See CAMPHOR, MONOBROMATED.

=MONOMA′NIA.= See INSANITY.

=MOR′DANT.= In _dyeing_ and _calico printing_, any substance employed to fix the colouring matter of dye-stuffs in the fibres of organic bodies, and to give it brilliancy and permanency. This it effects either by serving as a bond of union between the two, owing to its attraction for each of them; or it acts by uniting with the colouring particles in the minute pores of the fibres, and rendered them insoluble in the alkaline, soapy, and other liquids, to the action of which they will subsequently be exposed. When an infusion of some dye-stuff, as cochineal or madder, for example, is mixed with alum or acetate of alumina, and a little alkali, a precipitate immediately forms, consisting of alumina in combination with colouring matter, constituting a LAKE. It is by a similar reaction occurring within the fibres that the permanent dyeing of the cloth is effected. Here the colouring matter of the dyeing materials not only passes from the soluble to the insoluble form, but it enters into chemical combination with other substances, and in the new compounds it assumes greater brilliancy and permanency than it previously possessed. Annotta and safflower afford instances of the second mode of action above referred to, by which substances operate as mordants. The colouring matter of these dye-stuffs is soluble in alkaline lyes, and into a solution of this kind the cloth is dipped. It has now received an extremely fugitive colour only; but by passing it through acidulated water the alkaline solvent is abstracted, and the tinctorial matter is precipitated in an insoluble and minutely divided state within its pores, and it becomes permanently dyed. A similar reaction takes place in dyeing with the ‘indigo vat,’ in which atmospheric oxygen performs the part of a mordant. It is believed that even in these cases the colouring principle, during its transition from the liquid to the solid form, enters into combination with the fibres of the organic substance, and that, in proportion to the affinity existing between the two, is the integrity and excellence of the dye. In wool and silk the affinity between their filaments and the tinctorial particles of the dye-bath is, in general, so considerable, that a permanent stain is very easily communicated to them; but with cotton and flax, the materials of which calico and linen goods are made, the reverse is the case, and the intervention of a third material, in the shape of a mordant, is absolutely necessary to dye them of a permanent colour.

“Experience has proved that, of all the bases, those which succeed best as mordants are alumina, tin, and oxide of iron; the first two of which, being naturally white, are the only ones which can be employed for preserving to the colour its original tint, at least without much variation. But whenever the mordant itself is coloured, it will cause the dye to take a compound colour quite different from its own. If, as is usually said, the mordant enters into a real chemical union with the stuff to be dyed, the application of the mordant should obviously be made in such circumstances as are known to be most favorable to the combination taking place; and this is the principle of every day’s practice in the dye-house.

“In order that a combination may result between two bodies, they must not only be in contact, but they must be reduced to their ultimate molecules. The mordants to be united with stuffs are, as we have seen, insoluble in themselves, for which reason their particles must be divided by solution in an appropriate vehicle. Now, this solvent or menstruum will exert in its own favour an affinity for the mordant, which will prove to that extent an obstacle to its attraction for the stuff. Hence we must select such solvents as have a weaker affinity for the mordants than the mordants have for the stuffs. Of all acids which can be employed to dissolve alumina, for example, vinegar (acetic acid) is the one which will retain it with the least energy, for which reason the acetate of alumina is now generally substituted for alum, because the acetic acid gives up the alumina with such readiness that mere elevation of temperature is sufficient to effect the separation of these two substances. Before the substitution of the acetate, alum alone was employed; but without knowing the true reason, all the French dyers preferred the alum of Rome, simply regarding it to be the purest; it is only within these few years that they have understood the real grounds of this preference.

“The two principal conditions, namely, extreme tenuity of particles and liberty of action, being found in a mordant, its operation is certain. But as the combination to be effected is merely the result of the play of affinity between the solvent and the stuff to be dyed, a sort of partition must take place, proportioned to the mass of the solvent, as well as to its attractive force. Hence the stuff will retain more of the mordant when its solution is more concentrated, that is, when the base diffused through it is not so much protected by a large mass of menstruum; a fact applied to very valuable uses by the practical man. On impregnating, in calico printing, for example, different spots of the same web with the same mordant in different degrees of concentration, there is obtained in the dye-bath a depth of colour upon these spots intense in proportion to the strength of their various mordants. Thus, with solution of acetate of alumina in different grades of density, and with madder, every shade can be produced from the fullest red to the lightest pink, and with acetate of iron and madder, every shade from black to pale violet.” (Ure.)

In the employment of mordants in the ordinary processes of dyeing the goods are passed through the solution for a period varying, under different circumstances, according to the object in view. The cloth is subsequently aired, dried, and well rinsed, before immersing it in the colouring bath. In _calico printing_ the mordant is applied partially or topically to the cloth by means of wooden blocks, or some similar contrivance; or certain parts of the cloth are stopped out by a suitable preparation, or ‘resist,’ by which means a pattern is produced, as the colouring matter of the dye-bath is removed from the other portions by the washing or scouring to which it is subsequently subjected. The substances used to thicken the mordant by the calico printers, to prevent them spreading, are starch and British gum. The first is prepared for neutral solutions; the last for acidulous ones. The removal of the undecomposed particles of the mordant, so as to preserve the other portion of the cloth from their action, is effected by the process of DUNGING (which _see_).

The process of GALLING or ROOTING, commonly employed as a preparation of cotton and linen for fast dyes, consists in working the stuff for some time, at a good hand heat, in a decoction of galls or an infusion of sumach. In this case the astringent matter plays the part of a mordant. About 2-1/2 oz. of galls, or 5 oz. of sumach, and 3 or 4 pints of water, are commonly taken for every lb. of cotton. See CALICO PRINTING, DYEING, and the respective dye-stuffs and mordants.

=Mordant.= In _gilding_, any sticky matter by which gold-leaf is made to adhere. _Prep._ 1. Water or beer, rendered adhesive by the addition of a little gum, sugar, or honey, and tinged with a little gamboge or carmine, to mark the parts to which it is applied. Used to attach gold leaf to paper, taffety, vellum, &c.

2. (Mixtion.) From asphaltum, 1 part; mastic, 4 parts; amber, 12 parts; fused together, and then mixed with hot boiled oil, 1 pint. Used for gilding wood, &c. See GOLD SIZE.

=MORPHIA.= C_{17}H_{19}NO_{3}. _Syn._ MORPHINE (Ph. D.), MORPHINA, MORPHIUM, L. The chief active principle of opium. Morphia was discovered by Ludwig in 1688, but it was first obtained pure, and its precise nature pointed out by Sertuerner in 1804. It is peculiar to the _Papaveraceæ_, or poppy family.

_Prep._ 1. (Ph. D.) Turkey opium (cut into thin slices), 1 lb., is macerated for 24 hours in water, 1 quart, and the liquid portion decanted; the residuum is macerated for 12 hours with a second quart of water, and the process is repeated with a third quart of water, after which the insoluble portion is subjected to strong pressure; the mixed liquids are evaporated by water or steam heat to a pint, and filtered through calico; to the filtrate is added a solution formed of chloride of calcium, 6 dr., dissolved in distilled water, 4 fl. oz., and the liquid is further evaporated until it is so far concentrated that nearly the whole of it becomes solid on cooling; this is enveloped in a couple of folds of strong calico, and subjected to powerful pressure, the dark liquid which exudes being preserved for subsequent use; the squeezed cake is next treated with about 1/2 pint of boiling water, and the undissolved portion is washed on a paper filter; the filtered solution is again evaporated, and the solid portion thus obtained submitted to pressure, as before; if the product is not quite white, this process is repeated a third time; the squeezed cake is now dissolved in boiling water, 6 fl. oz., and the solution filtered through animal charcoal (if necessary); to the clear solution is added ammonia, in slight excess; the crystalline precipitate which forms as the liquid cools is collected on a paper filter, washed with cold distilled water, and, lastly, the filter is transferred to a porous brick, in order that the morphia which it contains may become dry. (From the liquids reserved from the expressions more morphia may be obtained by dilution with water, precipitation with ammonia, re-solution in boiling water, and treatment with a little animal charcoal, &c., as before.)

2. (Ph. L. 1836.) Hydrochlorate of morphia, 1 oz., is dissolved in distilled water, 1 pint; and ammonia, 5 fl. dr. (or q. s.), previously diluted with water, 1 fl. oz., is added, with agitation; the precipitate is well washed in distilled water, and dried by a gentle heat. By a similar process morphia may be obtained from its other salts.

3. (Merck.) A cold aqueous infusion of opium is precipitated with carbonate of sodium, in excess; the precipitate washed, first with cold water, and then with cold alcohol of sp. gr. 85; the residuum is dissolved in weak acetic acid, the solution filtered through animal charcoal, and precipitated with ammonia; the precipitate is again washed with cold water, dissolved in alcohol, and crystallised. A good process where spirit is cheap.

4. (Mohr.) Opium, 4 parts, is made into a strong infusion with water, q. s.; lime, 1 part, reduced to a state of milk with water, is then added; the mixture is next heated to boiling, at once filtered through linen, and treated, whilst still hot, with chloride of ammonium, in fine powder, in slight excess (about 1 oz. to each lb. of opium); the morphia is deposited as the liquid cools, and may be purified by a second solution in lime and precipitation by chloride of ammonium. This process is remarkably simple, and in many points is preferable to any other, either on the small or large scale.

5. (PURE.) A filtered solution of opium in tepid water is mixed with acetate of lead in excess; the precipitate (meconate of lead) is separated by a filter, and a stream of sulphuretted hydrogen is passed through the nearly colourless filtrate; the latter is warmed, to expel excess of the gas, once more filtered, and then mixed with a slight excess of ammonia, which throws down narcotine and morphia; these are separated by boiling ether, in which the former is soluble.

_Prop._ The morphia of commerce is a white crystalline powder; but when crystallised from alcohol, it forms brilliant prismatic crystals of adamantine lustre, and the formula C_{17}H_{19}NO_{3}.H_{2}O. It exerts an alkaline reaction on test paper; imparts a perceptible bitter taste to water; requires 1160 parts of cold water, and 94 parts of boiling water, for its solution; insoluble in ether; dissolves in 90 parts of cold and about 30 parts of boiling alcohol; it also dissolves in the fixed and volatile oils, and in solutions of the alkalies; heated in close vessels, it forms a yellow liquid, like melted sulphur, which becomes white and crystalline on cooling; heated in the air, it melts, inflames like a resin, and leaves a small quantity of charcoal behind. With the acids it forms salts, which are mostly soluble and crystallisable. These may all be made by the direct solution of the alkaloid in the dilute acid. The only ones of importance are the acetate, hydrochlorate, and sulphate.

_Pur._ Commercial morphia and its preparations are often contaminated with codeine, narcotine, and colouring matter. The proportion of the first two may be estimated by the loss of weight which the sample suffers when digested in ether; or by dissolving out the morphine by digestion in weak liquor of potassa. Pure morphia “is scarcely soluble in cold water, sparingly so in boiling water, and readily so in alcohol. This solution is alkaline to test paper, and by evaporation leaves crystals, which are wholly dissipated by heat. It is soluble in pure potassa.” (Ph. L. 1836.)

_Tests._ 1. Potassium hydrate and ammonia precipitate morphia from solution of its salts, under the form of a white crystalline powder, which is very soluble in excess of hydrate of potassium, and, with somewhat more difficulty, in excess of ammonia. The solution formed by excess of the first is precipitated on the addition of bicarbonate of potassium. The precipitate in either case is soluble in a solution of chloride of ammonium, and in dilute acetic acid, and is insoluble in ether. A careful inspection of the precipitate through a lens of small power shows it to consist of minute acicular crystals; and seen through a glass which magnifies 100 times, these crystals present the form of right rhombic prisms.——2. The carbonates of potassium and sodium produce the same precipitate as hydrate of potassium, and which is insoluble in excess of the precipitant.——3. The bicarbonates of potassium and sodium also give similar precipitates from neutral solutions, insoluble in excess. In each of the above cases stirring with a glass rod and friction on the sides of the vessel promote the separation of the precipitate.——4. If to a mixture of morphia and oil of vitriol a minute fragment of bichromate of potassium be added, oxide of chromium is set free, and a fine green colour developed.——5. A drop or two of solution of terchloride of gold added to a weak solution of morphia gives a yellow precipitate, which is mostly redissolved on agitating the liquid, which then assumes various hues (green, blue, violet, purple) on the addition of a drop of liquor of potassa.——6. A minute fragment of terchloride of gold and of hydrate of potassium very gently dropped into the liquid, occasion purple clouds or streaks in dilute solutions, followed by a precipitate, which is violet, purple, or blue-black, according to the strength of the liquid.

Another test, given by Siebold,[41] is the following:——“Heat the substance which is believed to be, or to contain, morphia, gently with a few drops of sulphuric acid, add a very small quantity of pure perchlorate of potassium. The liquid immediately surrounding the perchlorate will at once assume a deep brown colour, which will soon spread and extend over the greater part of the acid. Warming increases the delicacy of the test. 0·0001 gramme of morphia can be distinctly recognised in this way, and no other alkaloid is acted upon in a similar way by the substances named. It is indispensable, however, for the success of the experiment that the perchlorate of potassium be absolutely free from chlorate.” See ALKALOIDS.

[Footnote 41: ‘Year Book of Pharmacy,’ 1873.]

The above are the most reliable precipitates for morphia; the first two may, indeed, be regarded as characteristic, and the remainder as almost so. The following are often referred to by medical writers, but are less exclusive and trustworthy:——Morphia and its salts are——7. Reddened by nitric acid, and form orange-red solutions, darkened by ammonia in excess, and ultimately turning yellow, with the production of oxalic acid.——8. They are turned blue by ferric chloride, either at once or on the addition of an alkali, and this colour is destroyed by water and by alkalies, or acids in excess.——9. Iodic acid added to their solutions turns them yellowish brown, by setting iodine free, and the liquid forms a blue compound with starch.

_Uses._ Morphia and its salts are exhibited either in substance, made into pills, or in solution, generally the latter; or externally, in fine powder, applied to the dermis denuded of the cuticle. They are principally employed as anodynes and hypnotics in cases in which opium is inadmissible, and are justly regarded as the most valuable medicines of their class. “In cases wherein both opium and the morphine salts are equally admissible, I prefer the former, its effects being better known and regulated; moreover, opium is to be preferred as a stimulant and sudorific, and for suppressing excessive mucous discharges.” (Pereira.)——_Dose._ Of pure morphia, 1/12 to 1/6 gr.; of its salts, 1/8 to 1/4 gr.; externally, 1/2 to 1-1/2 gr. Morphine is chiefly used for the preparation of the acetate, and some of its other salts.

Good opium yields from 10% to 13% of morphia. See OPIUM.

=Morphia, Ac′etate of.= C_{17}H_{20}NO_{3}C_{2}H_{3}O_{2}. _Syn._ MORPHIÆ ACETAS (Ph. L., E., & D.), L. _Prep._ 1. (Ph. L. 1836.) Morphia, 6 dr.; acetic acid (Ph. L.), 3 fl. dr.; distilled water, 4 fl. oz.; dissolve, gently evaporate, and crystallise.

2. (Ph. E.) Hydrochlorate of morphia, 1 part, is dissolved in warm water, 14 parts; and the solution, when cold, is precipitated with ammonia, in slight excess, the precipitate is washed in cold water, and dissolved by means of acetic acid, in excess, in warm water, 12 parts; from the solution crystals are obtained as before.

3. (Ph. D.) Morphia (in fine powder), 1 oz.; rectified spirit, 8 fl. oz.; mix, apply a gentle heat, and add of acetic acid (sp. gr. 1·044), 4-1/2 fl. dr. or q. s., until a neutral or slightly acid solution is obtained; evaporate this to the consistence of a syrup by steam or water heat, and set aside the residuum for a few days until it solidifies.

4. (Ph. L.) Similar to the Edinburgh process.

_Pur._ “Soluble in water and in rectified spirit” (less so in the former than the latter); “and when the spirit is distilled from the solution, it yields crystals which are totally destroyed by heat.” (Ph. L.) “100 measures of a solution of 10 gr. in 1/2 fl. oz. of water, and 5 minims of acetic acid, heated to 212° and decomposed by a very slight excess of ammonia, yield by agitation a precipitate which, in 24 hours, occupies 15-1/2 measures of the liquid.” (Ph. E.)

_Obs._ The acetate of morphia of commerce is usually in the form of a whitish powder, and is prepared by the mere evaporation of the solution to dryness by a gentle heat. During the process a portion of the acetic acid is dissipated, and hence this preparation is seldom perfectly soluble in water, unless it has been slightly acidulated with acetic acid. In the Ph. L. 1851 this salt (in crystals) is included in the materia medica. See MORPHIA (_above_).

=Morphia, Hydri′odate of.= C_{17}H_{19}NO_{3},HI. _Syn._ MORPHIÆ HYDRIODAS, L. _Prep._ (A. T. Thomson.) Hydrochlorate of morphia, 2 parts; iodide of potassium, 1 part; dissolve each separately in a little water, mix the solutions, wash the precipitate in a little very cold water, press it in bibulous paper, redissolve it in hot water, and crystallise.

=Morphia, Hydriodate of, with Iodine.= _Syn._ MORPHIÆ HYDRIODAS CUM IODINIO; BOUCHARDAT’S IODURE D’IODHYDRATE, &c.; MORPHINE. _Prep._ Mix an acid solution of sulphate of morphia with an ioduretted solution of iodide of potassium, keeping the liquid at the temperature of 140° for an hour.

Pour off the liquid, wash the scales, and dry them.——_Dose_, 3/4 gr. at bedtime.

=Morphia and Hydriodate of Zinc with Iodine.= (Bouchardat.) _Syn._ MORPHIÆ ET ZINCI HYDRIODAS CUM IODINIO. _Prep._ Boil 1 scruple of ioduretted hydriodate of morphia with 2 fl. oz. of water and 10 scruples of zinc. After some days’ action filter the boiling liquid, which deposits the salt. Make 1-1/2 gr. into 8 pills, with powdered marshmallow root and syrup.

=Morphia, Hydrochlo′′rate of.= C_{17}H_{19}NO_{3},HI. _Syn._ MURIATE OF MORPHIA; MORPHIÆ HYDROCHLORAS (Ph. L. & Ph. B.), MORPHIÆ MURIAS (Ph. E., D. & U. S.), L. _Prep._ 1. (Ph. L. 1836.) Macerate sliced opium, 1 lb., in water, 4 pints, for 30 hours; then bruise it, digest it for 20 hours more, and press it; macerate what remains a second and a third time in water until exhausted, and as often bruise and press it; mix the liquors, and evaporate at 140° Fahr. to the consistence of a syrup; add of water, 3 pints, and after defecation decant the clear portion; gradually add to this liquid crystallised chloride of lead, 2 oz. (or q. s.), dissolved in boiling water, 4 pints, until it ceases to produce a precipitate; decant the clear liquid, wash the residuum with water, and evaporate the mixed liquids, as before, that crystals may form; press these in a cloth, then dissolve them in distilled water, 1 pint, add freshly burnt animal charcoal, 1-1/2 oz., digest at 120°, and filter; finally, the charcoal being washed, cautiously evaporate the mixed liquors, that pure crystals of hydrochlorate of morphia may form. To the decanted liquor from which the crystals were first separated, add of water, 1 pint, and drop in liquor of ammonia, frequently shaking, until all the morphine is precipitated; wash this precipitate with cold distilled water, saturate it with hydrochloric acid, digest with animal charcoal, 2 oz.; filter, wash the filtrate as before, and evaporate the mixed liquors, cautiously, as above, that pure crystals may be obtained.

2. (Ph. E.) Opium, 20 oz., is exhausted with water, 1 gall., in the quantity of a quart at a time, and the mixed liquors are evaporated to a pint; chloride of calcium, 1 oz., dissolved in water, 4 fl. oz., is added, and, after agitation, the liquid is placed aside to settle; the clear decanted liquid, and the washings of the sediment, are next evaporated, so that they may solidify on cooling; the cooled mass, after very strong pressure in a cloth, is redissolved in warm water, a little powdered white marble added, and the whole filtered; the filtrate is acidulated with hydrochloric acid, the solution again concentrated for crystallisation, and the crystals submitted to powerful pressure, as before; the process of solution, clarification, with powdered marble and hydrochloric acid, and crystallisation, is repeated until a snow-white mass is obtained. This is the process of Gregory and Robertson, and is one of the easiest and most productive on the large scale. To procure the salt quite white, 2 to 4 crystallisations are required, according to the power of the press employed. The Edinburgh College recommends, on the small scale, the solution, after two crystallisations, to be decoloured by means of animal charcoal; but, on the large scale, to purify the salt by repeated crystallisations alone.

3. (Ph. B.) Macerate opium, sliced, 1 lb., for 24 hours with distilled water, 2 pints, and decant. Macerate the residue for 12 hours with distilled water, 2 pints, decant, and repeat the process with the same quantity of water, subjecting the insoluble residue to strong pressure.

Unite the liquors, evaporate on a water bath to the bulk of 1 pint, and strain through calico. Pour in now chloride of calcium, 3/4 oz., previously dissolved in 4 fl. oz. of distilled water, and evaporate until the solution is so far concentrated that upon cooling it becomes solid. Envelope the mass in a double fold of strong calico, and subject it to powerful pressure, preserving the dark fluid which exudes. Triturate the squeezed cake with about 1/2 pint of boiling distilled water, and, the whole being thrown upon a paper filter, wash the residue well with boiling distilled water. The filtered fluids having been evaporated as before, cooled, and solidified, again subject the mass to pressure, and if it be still much coloured, repeat this process a third time, the expressed liquids being always preserved. Dissolve the pressed cake in 6 fl. oz. of boiling distilled water, add purified animal charcoal, 1/4 oz., and digest for 20 minutes; filter; wash the filter and charcoal with boiling distilled water, and to the solution thus obtained add solution of ammonia in slight excess. Let the pure crystalline morphia which separates as the liquid cools be collected on a paper filter, and washed with cold distilled water until the washings cease to give a precipitate with solution of nitrate of silver acidulated with nitric acid.

From the dark liquids expressed in the above process an additional product may be obtained by diluting them with distilled water, precipitating with solution of potash added in considerable excess, filtering, and supersaturating the filtrate with hydrochloric acid. This acid liquid, digested with a little animal charcoal, and again filtered, gives upon the addition of ammonia a small quantity of pure morphia. Diffuse the pure morphia obtained as above through 2 oz. of boiling distilled water placed in a porcelain capsule, kept hot, and add, constantly stirring, dilute hydrochloric acid, 2 fl. oz., or q. s., proceeding with caution, so that the morphia may be entirely dissolved and a neutral solution obtained. Set aside to cool and crystallise. Drain the crystals and dry them on filtering paper. By further evaporating the mother liquor, and again cooling, additional crystals are obtained.——_Dose._ From 1/8th to 1/2 gr.

4. (Mohr.) By dissolving the precipitate of morphia (see MORPHIA, _Prep._ 4) in dilute hydrochloric acid, and by crystallisation, as before.

_Pur., &c._ It “is completely soluble in rectified spirit, and in water. What is precipitated from the aqueous solution by nitrate of silver is not entirely dissolved, either by ammonia, unless added in excess, or by hydrochloric or nitric acid.” (Ph. L.) “Snowy white; entirely soluble; solution colourless; loss of weight at 212° Fahr. not above 13%; 100 measures of a solution of 10 gr., in water, 1/2 fl. oz., heated to 212°, and decomposed with agitation by a faint excess of ammonia, yield a precipitate which, in 24 hours, occupies 12-1/2 measures of the liquid.” (Ph. E.) It takes 20 parts of cold and about its own weight of boiling water to dissolve it. The hydrochlorate of morphia of the shops is usually, like the acetate, under the form of a white crystalline powder.

_Obs._ Of all the salts of morphia, this one appears to be that most suitable for medical purposes, from its free solubility, and from its solution not being liable to spontaneous decomposition, at least under ordinary circumstances. “The opium which yields the largest quantity of precipitate by carbonate of sodium yields muriate of morphia, not only in the greatest proportion, but also with the fewest crystallisations.” (Ph. E.) Smyrna opium contains the most morphine.

=Morphia and Codei′a (Hydrochlorate of).= _Syn._ GREGORY’S SALT; MORPHIÆ ET CODEIÆ HYDROCHLORAS, L.; SEL DE GREGORY, Fr. This is commercial HYDROCHLORATE OF MORPHINE prepared according to Dr Gregory’s process.

=Morphia Mec′onates of.= (C_{19}H_{20}NO_{3})_{2},C_{7}H_{2}O_{7}. _Prep._ 1. (NEUTRAL MECONATE OF MORPHINE; MORPHIÆ MECONAS, L.) By saturating an aqueous solution of meconic acid with morphia, and evaporating the solution by a gentle heat, so that crystals may be obtained.

(2.) BIMECONATE OF MORPHINE; (MORPHIÆ BIMECONAS, L.) C_{17}H_{19}NO_{3}HC_{7}H_{3}O_{7}. Meconic acid, 11 parts; morphia, 14 parts; dissolve each separately in hot water, q. s.; mix the solutions, and either gently evaporate and crystallise, or at once evaporate to dryness.

_Obs._ Morphia exists in opium under the form of bimeconate, and hence this preparation of that drug has been preferred by some practitioners. A solution of this salt for medical purposes may be directly prepared from opium, by treating its solution in cold water with a little animal charcoal, filtering, gently evaporating to dryness, redissolving the residuum, in cold water, filtering, and repeating the treatment with animal charcoal. The dose of the dry bimeconate is 1/4 gr., or more; and of the meconate rather less. “A powder is also sold, called ‘bimeconate of morphia,’ which is of the same strength as powdered opium, and is given in similar doses. It is obviously incorrect to apply this name to a powder which consists principally of foreign matter. It is to be hoped that physicians will not prescribe this powder under the above name, as such a practice might lead to fatal results, if the prescription should be prepared with the substance which the name strictly indicates.” (REDWOOD.)

=Morphia, Nitrate of.= (A. T. Thomson.) _Syn._ MORPHIÆ NITRAS. Add morphia in slight excess to very dilute nitric acid, filter, concentrate by gentle evaporation, and set aside that crystals may form.

=Morphia, Phosphate of.= _Syn._ MORPHIÆ PHOSPHAS. As the nitrate, substituting dilute phosphoric by nitric acid.

=Morphia, Sul′phate of.= _Syn._ MORPHIÆ SULPHAS, L. _Prep._ Saturate very dilute sulphuric acid with morphia, evaporate to one half, add a little animal charcoal, continue the evaporation for a short time longer at a gentle heat, filter whilst hot, and abandon it to spontaneous evaporation. It is decomposed by driving off the water of crystallisation. Sulphate of morphia is included in the Ph. U. S. According to Magendie, this salt sometimes agrees with patients who cannot bear the acetate.

=Morphia, Tartrate of.= (A. T. Thomson.) _Syn._ MORPHIÆ TARTRAS. _Prep._ Saturate a solution of tartaric acid with morphiæ, concentrate by evaporation, and set aside that crystals may form. By using an excess of acid an acid tartrate may be formed.

=MORPHIOM′ETRY.= A name given to the process of determining the richness of opium in morphia. See OPIUM.

=MORISON’S PILLS.= See _Patent medicines_.

=MORSU′LI.= An old name applied to lozenges and masticatories. It is still retained in some foreign Pharmacopœias.

=MOR′TAR= is the well-known cement, made of lime, sand, and water, employed to bind bricks and stones together in the construction of walls, buildings, &c.

In the composition of mortar stone lime is preferred to that obtained from chalk, and river sand to pit or road sand. Sea sand is unfitted for mortar until it has been well soaked and washed in fresh water. Sifted coal ashes are frequently substituted for the whole or a part of the sand.

HYDRAULIC MORTARS or CEMENTS are those which, like Roman cement, are employed for works which are either constantly submerged or are frequently exposed to the action of water. The poorer sorts of limestone are chosen for this purpose, or those which contain from 8% to 25% of alumina, magnesia, and silica. Such limestones, though calcined, do not slake when moistened; but if pulverised, they absorb water without swelling up or heating, like fat lime, and afford a paste which hardens in a few days under water, but in the air they never acquire much solidity.

“The essential constituents of every good hydraulic mortar are caustic lime and silica; and the hardening of this composition under water consists mainly in a chemical combination of these two ingredients through the agency of the water, producing a hydrated silicate of lime. But such mortars may contain other ingredients besides lime, as, for example, clay and magnesia, when double silicates of great solidity are formed; on which account dolomite is a good ingredient in these mortars. But the silica must be in a peculiar state for these purposes, namely, capable of affording a gelatinous paste with acids; and if not so already, it must be brought into this condition, by calcining it along with an alkali or an alkaline earth, at a bright red heat, when it will dissolve and gelatinise in acids. Quartzose sand, however fine its powder may be, will form no water mortar with lime; but if the powder be ignited with the lime, it then becomes fit for hydraulic cement. Ground felspar or clay forms with slaked lime, no water cement; but when they are previously calcined along with the lime, the mixture becomes capable of hardening under water.

“All sorts of lime are made hydraulic, in the humid way, by mixing the slaked lime with solutions of common alum or sulphate of alumina; but the best method consists in employing a solution of the silicate of potash, called liquor of flints or soluble glass, to mix in with the slaked lime or lime and clay. An hydraulic cement may also be made which will serve for the manufacture of architectural ornaments, by making a paste of pulverised chalk, with a solution of the silicate of potash. The said liquor of flints likewise gives chalk and plaster a stony hardness, by merely soaking them in it after they are cut or moulded to a proper shape. On exposure to the air they get progressively indurated. Superficial hardness may be readily procured by washing over the surface of chalk, &c., with liquor of flints, by means of a brush. This method affords an easy and elegant method of giving a stony crust to the plastered walls and ceilings of apartments; as also to statues and busts cast in gypsum mixed with chalk.”

Under Prof. Kuhlman’s patent, dated April, 1841, “instead of calcining the limestone with clay and sand alone, as has been hitherto commonly practised, this inventor introduces a small quantity of soda, or, preferably, potash, in the state of sulphate, carbonate, or muriate; salts susceptible of forming silicates when the earthy mixture is calcined. The alkaline salt, equal in weight to about 1-5th that of the lime, is introduced in solution among the earths.” (Ure.)

The hardening of the common mortars and cements is in a great measure due to the gradual absorption of carbonic acid; but even after a very great length of time this conversion into carbonate is not complete. Good mortar, under favorable circumstances, acquires extreme hardness by age.

Attempts have been made at various times to introduce the use of bituminous cements into this country, and thus to restore both to land and submarine architecture a valuable material which has now lain neglected for a period of fully thirty centuries; but, unfortunately, owing to the interest of our great building and engineering firms lying in another direction, these attempts have been hitherto unsuccessful. See ASPHALTUM, CEMENT, LIME, &c.

=MORTIFICA′TION= _Syn._ GANGRENE; GANGRENA, MORTIFICATION, L. Local death; the loss of vitality in one part of the animal body, whilst the rest continues living. “The terms gangrene and mortification are often used synonymously; but gangrene properly signifies the state which immediately precedes mortification, while the complete mortification, or absolute death of a part, is called sphacelus. A part which has passed into the state of sphacelus is called a slough.

=MOSA′IC GOLD.= See BRASS, GOLD, &c.

=MOS′SES.= _Syn._ MUSCI, L. Several vegetables of the natural orders _Algæ_, _Fungi_, _Lichenes_, and _Musci_, commonly pass under this name with the vulgar. Of these the following are the principal:——

BOG MOSS (_Sphagnum palustre_). Very retentive of moisture. Used to pack up plants for exportation.

CEYLON MOSS (_Gracilaria candida_). Very nutritive; made into a decoction or jelly, which is highly esteemed as an article of diet for invalids and children, more especially for those suffering under affections of the mucous membranes or phthisis.

CLUB MOSS (_Lycopodium clavatum_). See LYCOPODIUM.

CORSICAN MOSS, C. WORM M. (_Gracilaria Helminthocorton_).——_Dose_, 1/2 to 2 dr., in powder, mixed up with sugar; as a vermifuge.

CUP MOSS, C. LICHEN (_Cladonia pyxidata_). Astringent and febrifuge. A cupful of the decoction, taken warm, generally proves gently emetic. Used in hooping-cough, &c.

FIR CLUB MOSS (_Lycopodium Selago_). Violently emetic and purgative. It is also irritant and narcotic.

ICELAND MOSS (_Cetraria Islandica_). Highly nutritious and easy of digestion. The decoction is a favourite alimentary substance in affections of the lungs and digestive organs. In Iceland, after the bitter has been removed by soaking it in hot water, it is made into jelly, or dried, ground to flour, and made into bread.

IRISH MOSS, PEARL M., CARRAGEEN M. (_Chondrus crispus_). Very nutritious. The decoction or jelly is a useful and popular demulcent and emollient in pulmonary affections, dysentery, scrofula, rickets, &c. It is often employed by cooks and confectioners instead of isinglass, and by painters to make their size.

REINDEER MOSS (_Cladonia rangiferina_). Esculent, very nutritious.

=MOTHER-OF-PEARL.= See PEARL.

=MOTH′ER WATER.= See CRYSTALLISATION.

=MOULDS.= Numerous materials and compositions are employed for the purpose of taking moulds, among which are the following:

1. (COMPO’.)——_a_ From spermaceti, stearine or hard tallow, and white wax, equal parts, melted together. For fine work, as medals, small casts, &c.

_b._ From black resin, 3/4 lb.; hard tallow, 1/2 lb.; beeswax, 6 oz.; as the last. For coarse work, as architectural ornaments, &c. The above are poured on the objects to be copied (previously oiled) whilst in the melted state. Articles in plaster of Paris are first soaked in water, observing that none of it remains on the surface so as to interfere with the design.

2. (ELASTIC.)——_a._ Flexible or elastic moulds may be made of gutta percha softened in boiling water, and after being freed from moisture, pressed strongly against the object to be copied by means of a screw press. A ring or support should be employed to prevent undue lateral spreading.

_b._ By the use of gelatin or glue, elastic moulds are formed capable of reproducing, with accuracy, and in a single piece, the most elaborately sculptured objects, of exquisite finish and delicacy. Casts from these are now common in the streets. The credit of the application of this substance to this purpose is due to M. H. Vincent. The process of casting consists in simply dissolving a certain quantity of gelatin in hot water until it is reduced to the state of liquid paste, when it is run over the object, previously oiled, intended to be reproduced. As it cools, the gelatin assumes a consistency offering a considerable degree of resistance, and is highly elastic, which latter quality enables it to be easily detached from the work on which it has been fitted. In the hollow formed by the gelatin the finest plaster, mixed to a thick cream with water, is next run; and when the plaster has acquired the requisite hardness, the gelatin mould is detached in the same manner as from the original. From this apparently fragile mould as many as six copies may be taken, all reproducing the original with unerring fidelity.

3. (METALLIC.)——_a._ From fusible metal.[42]

[Footnote 42: See FUSIBLE ALLOYS.]

_b._ (CLICHÉE MOULDS.) From a fusible alloy formed of bismuth, 8 parts; lead, 5 parts; tin, 4 parts; antimony, 1 part; repeatedly melted together. The above are poured out in the melted state on a plate or slab, and after being stirred until in a pasty state, the object to be copied is strongly pressed on the alloy at the moment it begins to solidify. They are chiefly used for medals and other like objects.

_c._ (Chameroy’s Patent.) By melting together one part of some easily fusible metal in a crucible, and then mixing with it four parts of a metal far less readily fusible, steeped in ammonia and reduced to powder. Such a compound is stated to be of great solidity, hardness, facility of soldering, melts at a low temperature, and has great tractability in moulding to any form; and in casting takes the sharpest impressions, whilst in its nature it is peculiarly unchangeable. See ELECTROTYPE.

=MOUTH COSMET′ICS.= See BREATH, TEETH, LOZENGE, PASTE, POWDER, &c.

=MOX′AS.= Substances burnt upon the body, for the purpose of acting as counter-irritants, and allaying deep-seated pains and inflammation. They have been used in gout, rheumatism, &c. The small cone constituting the moxa is placed upon a part, lighted, and allowed to burn to its base. The CHINESE and JAPANESE moxas are made of the downy portion of the leaves of a species of wormwood (_Artemisia sinensis_); but various other substances, as the pith of the sunflower, cotton, or paper, soaked in a weak solution of nitrate, chlorate, or chromate of potassium, answer as well. Larrey’s moxas consist of lycopodium, 4 oz.; nitre, 2 oz.; formed into small cones, with alcohol, and dried for some days. Dr Osborne used quicklime enclosed in a hoop of card, and moistened with water. The actual cautery is said to be preferable to any of them.

=MU′CILAGE.= _Syn._ MUCILAGO, L. An aqueous solution of gum, or other like substance, that gives a considerable consistency to water. See DECOCTION, MIXTURE, &c.

=Mucilage, Acacia.= (Ph. B.) _Syn._ MUCILAGO ACACIÆ. Put gum acacia, in small pieces, 4 oz., and distilled water, 6 oz., into a covered earthen jar, and stir frequently until the gum is dissolved. If necessary, strain through muslin.

=Mucilage, Fenugreek.= _Syn._ MUCILAGO FENUGRECI. Digest 1 oz. of fenugreek seed with 1/2 pint of water for 12 hours, boil, and strain with pressure.

=Mucilage, Linseed.= (P. Cod.) _Syn._ MUCILAGO LINI. Linseed, 1 oz.; warm water, 6 oz. Digest for 6 hours, stirring now and then, and strain.

=Mucilage, Liquorice.= _Syn._ MUCILAGO GLYCYRRHIZÆ. From liquorice root, as MARSHMALLOW MUCILAGE.

=Mucilage, Marshmallow.= (P. Cod.) _Syn._ MUCILAGO ALTHÆÆ. Marshmallow root, 1 oz.; boiling water, 6 oz.; digest for 6 hours, and strain.

=Mucilage, Quicksilver.= _Syn._ MUCILAGO MERCURIALIS PLENKII. Quicksilver, 1 dr.; gum Arabic, 3 dr.; syrup of poppies, 4 oz. Mix.——_Dose_, 1/2 dr.

=Mucilage, Sassafras.= (Ph. U. S.) _Syn._ MUCILAGO SASSAFRAS. Infuse 2 dr. of pith of sassafras in 16 oz. (old measure) of boiling water for 3 hours, and strain.

=Mucilage, Slippery-Elm Bark.= (Ph. U. S.) _Syn._ MUCILAGO ULMI. Slippery-elm bark, sliced and bruised, 1 oz.; boiling water, 16 oz. Infuse for 2 hours.

=Mucilage, Starch.= (Ph. B.) Same as DECOCTION OF STARCH (Ph. L.), which _see_.

=Mucilage, Tra′gacanth.= _Syn._ MUCILAGO TRAGACANTHÆ (B. P., Ph. E., and Ph. D 1826), L. _Prep._ 1. (Ph. E.) Tragacanth, 2 dr.; boiling water, 9 fl. oz. (8 fl. oz.——Ph. D.); macerate for 24 hours, triturate, and press through linen.

2. (B. P.) Tragacanth, in powder, 60 gr.; distilled water, 10 oz. To the water contained in a pint bottle add the tragacanth, agitate briskly for a few minutes, and again at short intervals, until the tragacanth is perfectly diffused, and has finally formed a mucilage.——_Dose_, 1 oz. (Should be made as required. One part of tragacanth gives more viscosity to water than twenty-five parts of gum Arabic——Squire.) Used in medicine as a demulcent, and as an application to burns, &c., and in pharmacy in making up pills, and to suspend heavy powders in liquids.

=MUDAR′IN.= _Syn._ MADARINE. A peculiar substance, possessing powerful emetic properties, extracted from the root bark of _Calotropis gigantea_, in which it exists to the extent of 11%. (Duncan.) It is soluble in water and in alcohol, and its aqueous solution, unlike that of most other substances, gelatinises by heat, and becomes fluid again on cooling.

=MUF′FINS.= _Prep._ Take of fine flour, 1/4 peck; warm milk-and-water, 1 quart; yeast, a wine-glassful; salt, 2 oz.; mix for 15 minutes, then further add of flour, 1/4 peck, make a dough, let it rise 1 hour, roll it up, pull it into pieces, make them into balls, put them in a warm place, and when the whole dough is made into balls, shape them into muffins, and bake them on tins; turn them when half done, dip them into warm milk, and bake them to a pale brown.

=MUF′FLE.= See ASSAYING.

=MUL′BERRY.= _Syn._ MORUM, L. Mulberries (MORA, MORI BACCÆ) are the fruit of _Morus nigra_, or black mulberry tree. They are cooling and laxative; but when eaten too freely are apt to disorder the stomach and bowels. Mulberry juice (_mori succus_) is officinal in the Ph. L. A syrup (SYRUPUS MORI) is made of it. It is also, occasionally, made into wine.

=MUL′TUM.= A mixture of extract of quassia and liquorice, used by fraudulent brewers instead of malt and hops.

=MUM.= A beverage prepared from wheat malt, in a similar way to ordinary beer from barley malt. A little oat and bean meal is frequently added. It was formerly much drunk in England; but its use at the present day is chiefly confined to Germany, and to Brunswick more particularly.

=MUMPS.= _Syn._ PAROTITIS, L. Inflammation of the parotid gland, which is situated under the ear. There is little constitutional derangement, but the cheeks become swollen and painful, and there is some difficulty in opening the mouth, and in swallowing. The treatment consists in simply keeping the part warm with flannel, and the use of warm fomentations, at the same time that the bowels are kept freely open with some mild laxative.

The mumps are said to be contagious, as, when the affection appears in a school, it generally attacks every member of it. Low, damp situations are those most favorable to this affection.

=MUREX′ID.= C_{8}N_{6}H_{8}O_{6}. _Syn._ PURPURATE OF AMMONIUM.

_Prep._ (Gregory.) Alloxan, 7 parts; alloxantin, 4 parts; boiling water, 240 parts; dissolve, and add the solution to a cold and strong solution of carbonate of ammonia, 80 parts; crystals of murexid will separate as the liquid cools.

_Obs._ Murexid can be obtained directly from uric acid by the action of nitric acid and subsequent treatment with ammonia. This process is, however, very precarious, and often fails altogether.

_Prop., &c._ It is only very slightly soluble in cold water; freely soluble in solutions of ammonia and the fixed alkalies; the first, by exposure to the air, becomes purple, and deposits brilliant crystals of murexid. These compounds are the purpurates of Dr Prout. It forms iridescent crystals, having a metallic lustre, of a magnificent green colour by reflected light, and an equally beautiful reddish purple by transmitted light. It is soluble in boiling water, only very slightly soluble in cold water, and insoluble in alcohol and ether. A few years ago murexid was extensively used in dyeing; it is now almost superseded by rosaniline or magenta. An analogous substance, formed as above, by treating amalic acid with ammonia, is called ‘caffein-murexid.’

=MU′′RIATE.= An old name for hydrochlorate and chloride.

=MURIATIC ACID.= _Syn._ HYDROCHLORIC ACID, which _see_.

=MURIDE.= The name originally given to bromine by M. Balard.

=MUR′RAIN.= _Syn._ BLACK-LEG, BLACK-QUARTER. A disease affecting meat cattle, more especially young animals, in the spring and autumn. The common symptoms are swelling and discoloration of one of the hind quarters of the animal, with consequent lameness and inability to move; a peculiar emphysema and intumescence of various parts of the body, particularly over the region of the spine, accompanied with all the common indications of putrid fever. In severe cases gangrene soon follows, and death frequently ensues in from 12 to 24 hours.

The rapid progress of this disease admits of little being done in the way of cure. Extensive scarifications of the affected part, charcoal or hot yeast poultices, or fomentations, and active purgatives, appear to constitute the most useful treatment. The following drenches have been recommended for this affection:——

1. (Blaine.) Sweet spirit of nitre, 1/2 fl. oz.; powdered cascarilla, 2 oz.; solution of acetate of ammonia, 4 fl. oz.; yeast, 8 fl. oz.; given every 3 or 4 hours.

2 (Clater.) Laudanum and sweet spirit of nitre, of each 1/2 fl. oz.; solution of chloride of lime, 1/4 fl. oz.; prepared chalk, 1 oz.; warm gruel, 1 pint.

The apparent incurability of this disease renders it of the utmost importance to the farmer to adopt preventive measures. These should consist of the supply of wholesome food and pure water, the adoption of extreme cleanliness, and the free access of pure air to all the stalls, sheds, and other buildings in which the cattle may be sheltered. As the disease is regarded as contagious by many persons, it is prudent to separate, as speedily as possible, the healthy animals from those affected. The free use of sulphurous acid, chloride of lime, &c., as disinfectants, is also advisable.

Other and more immediate preventives consist of the occasional exhibition of a saline aperient, and the introduction of a seton into the dewlap.

=MUSCULAR POWER.= Fick and Wislicenus proved, in 1865, that muscular power is to a great extent produced by the oxidation of such non-nitrogenous substance as fat. Frankland has put the matter beyond dispute by a series of experiments determining the amount of potential energy locked up in muscle. Some of the conclusions at which he has arrived are extremely interesting. He considers that a muscle is a machine for the conversion of potential energy into mechanical force; that the mechanical force of the muscles is derived chiefly, if not entirely, from the oxidation of matters either contained in the blood or deposited around the muscular fibres, and not from the oxidation of the muscles themselves; that in man the chief materials used for the production of muscular power are non-nitrogenous; but nitrogenous matters can also be employed for the same purpose, and hence the greatly increased evolution of nitrogen, under the influence of a flesh diet, even with no increase of muscular exertion; that like every other part of the body, the muscles are constantly being renewed, but this renewal is scarcely perceptibly more rapid during great muscular activity than during comparative quiescence; that after the supply of sufficient albuminoid matters in the food of man to provide for the necessary renewal of the tissues, the best materials for the production both of internal and external work are non-nitrogenous matters, such as oil, fat, sugars, starch, and gum; that the non-nitrogenous matters of food which find their way into the blood yield up all their potential energy as actual energy; the nitrogenous matters, on the other hand, leave the body with a portion (at least one seventh) of their potential energy unexpended; and, lastly, that the transformation of potential energy into muscular power is necessarily accompanied by the production of heat within the body, even when the muscular power is exerted externally. This is doubtless the chief, and probably the only, source of natural heat. See ENERGY, EXERCISE.

=MUSH′ROOMS.= Edible fungi. The species commonly eaten in England are the _Agaricus campestris_, or common field or garden mushroom, used to make ketchup, and eaten either raw, stewed, or broiled;——the _Morchella esculenta_, or morel, used to flavour soups and gravies;——and the _Tuber cibarium_, or common truffle, also used as a seasoning.

Several fungi, which to the inexperienced closely resemble the common edible mushroom, possess poisonous narcotic properties, and their use has not unfrequently been productive of serious, and, in some cases, even fatal results. Unfortunately, no simple tests exist by which the edible and poisonous varieties can be distinguished from each other. So strongly was the late Professor L. C. Richards, the eminent botanist, impressed with this feeling, that though no one was better acquainted with the distinctions of fungi than he was, yet he would never eat any except such as had been raised in gardens, in mushroom beds.

“This difficulty of distinguishing edible from poisonous and noxious fungi must not be ignored. If only one out of a hundred, or for the matter of that a thousand, species were poisonous or noxious, it would not be sound advice to say that we should eat all that come to hand, and stand the chance of baneful results. Unfortunately it is the case that some of the most poisonous fungi are the most common, and there is scarcely a field, and perhaps not a single wood, which does not abound with varieties of _Coprinus_, the _Agaricus fascicularis_, and the beautifully coloured _Thussula emetica_, and several other very undesirable species. Some writers, and among them, if we remember rightly, the learned and enthusiastic mycologist, Dr Badham, deny the existence of any poisonous fungi in our islands, and they account for the effects which are often produced by eating varieties different from our common mushroom by stating that some people, through idiosyncrasy of constitution, are injuriously affected by all fungi; and in support of this statement they instance the well-known fact that some people experience the most unpleasant effects after eating the common edible mushroom, which chemically contains noxious ingredients. We all know that idiosyncrasy of constitution may account for much and for very strange phenomena; for instance, oysters are almost poison to some persons, while roast beef will cause hysterics in other cases; and to not a few certain odours, harmless in themselves, are causes of serious attacks of illness; but the fact remains that persons who can eat with impunity and greatly enjoy the common mushroom are unpleasantly affected by other species of fungi. Not a year passes but deaths are recorded of persons——sometimes of whole families——after eating noxious fungi, though they had no idiosyncrasy of constitution; and shortly prior to the writing of this article a learned botanist and enthusiastic mycologist, and a friend, in experimenting on some specimens of fungi sent to him, narrowly escaped death, while another person who partook of the dish prepared actually succumbed. A thousand and one tests have been given in writing from time to time whereby our ordinary mushroom is to be distinguished from species which resemble it——and one species is to be distinguished from another; but we fear that practically they are not to be depended upon. Fungi differ in appearance according to the localities in which they grow, and according to their age. The common belief that the edible species never change colour when cut or bruised is untenable, for three varieties at least are perfectly edible, and yet assume different tints when injured in any way. The test of taste, too, which is applied under the idea that those with a pleasant savour and an inoffensive smell are always wholesome, is fallacious, for a raw mushroom is quite a different thing from the stewed or grilled one, and often what has an acrid taste when raw becomes perfectly savoury when cooked; and, _vice versâ_, a tasteless fungus may be poisonous, but only develop its latent flavour when submitted to the cook. Dr Christison declares that a sure test of poisonous fungus is an astringent, styptic taste, and a disagreeable pungent odour; but this, again, cannot always be depended on. Nor, again, is the popular idea that a mushroom which will skin easily is wholesome altogether based on fact. What, then, is to be done to enlarge the field of our mushroom gatherers and to bring about the utilisation of food now suffered to run to waste, or, in other words, how is a knowledge of our fungi to be obtained? The only answer is that knowledge on this matter is to be got, generally speaking, as knowledge on other matters——partly from books, but more especially from oral instruction and demonstration. Such eminent authorities as Dr Badham, the Rev. M. Berkeley, Mr Cooke, and Mr Worthington Smith may be consulted with profit, and works such as that on ‘Domestic Economy,’ in which coloured plates bring accurately before the eye the different species of our fungi. And here we may mention that the plates prepared by Mr Worthington Smith, which were once at the South Kensington Museum, but now, we believe, at Bethnal Green, have done much to help the Londoner when in search for mushrooms in the country to distinguish between the good and bad species of fungi. It might be well that in our schools, where so many practically useless branches of knowledge are crammed into children both in town and country, practical lessons on fungi should be given. Those, too, who wish to learn what is to be learned on this subject should avail themselves of opportunities now often given at exhibitions and botanical meetings. At Paris, in 1876, there was an exhibition of edible and poisonous fungi, in a fresh and dry state, together with books and drawings; and a similar exhibition took place in Aberdeen two years before; and, as most of our readers are probably aware, there exists a Fungus Club, or, rather, a botanical society which makes fungi a special study. This is the Woolhope Club, which has its head quarters at Hereford, and embraces in its scientific investigations all the district between Shropshire and the Bristol Channel. One day in each autumn is devoted to a fungus hunt, and the numbers that are gathered by this enthusiastic band are something enormous. The labours of the day are closed by a dinner, at which the main dishes are composed of the spoils of the chase, dressed in the most epicurean fashion, and of other good things flavoured with the most appetising (fungus) sauces. In the annual volume published of the transactions of the club there is a description of the fungi of the district, and the best modes of cooking them. It would be a great gain to the public if at least that part dealing with fungi were generally obtainable.

“Gastronomically the ordinary mushroom, and a large number of our British fungi, are most estimable, and ketchup produced from them——not the ordinary ketchup ‘of commerce,’ which is often innocent of any fungi whatever——is to the cultivated taste of the gourmet the best of sauces. Many an epicurean has been heard to aver that after that of an oyster that of a mushroom is the finest in the whole world of gastronomy. Bacon, in his ‘Naturall Historie,’ says of mushrooms, ‘they yield a delicious meat,’ and to these commendations it may be added that they can be cooked in almost as many ways as the French can cook eggs. Their alimentary value is also great, for chemistry has revealed in them the presence of the leading principles which exist in the flesh of animals. Dr Letheby says that ‘the edible varieties are highly nutritious,’ and that well-known dietist, the late Dr Edward Smith, who was very chary of commending anything, also has a good word for them.

“Our word ‘mushroom’ is evidently an adaptation of the French _mousseron_, which, of course, is from _mousse_ ‘_moss_’ (Latin, _muscus_); but the suggestion of the learned Salmasius, that the French gave this name to the edible fungus ‘because it grows only where the grass is the shortest and there is little else but moss,’ strikes one as rather weak. The mushroom, like the moss, is a cryptogamous plant; but there is little connection in any way between the two. Perhaps, then, we must look to the Greek word _mucos_, though only used by the grammarians, for the origin of the French word and so of our own. This was one of the terms which signified a ‘sponge,’ and was probably applied to the ‘fungi’ because of their sponge-like growth. It is evident that some of our more exact botanists, or etymologists who compounded the word for them, consider the Greek word and not the Latin as the origin of the _mu_ in the English word and the _mou_ in the French, though, according to analogy, the _u_ should have been changed into a _y_, for the study of ‘fungi’ is termed by them _mycology_. It is hardly necessary to add that the words ‘fungology’ and ‘fungologist’ are hybrid compounds of Greek and Latin, which are simply intolerable to ears correct, as are many other words similarly compounded, and recently introduced into our language. The Latin _fungus_ is plainly a weakened form of the Greek _spongos_, and goes to show that the idea of a ‘sponge’ was from the first associated with the _fungi_, and that the Greek _mucos_ must be taken as the origin of the French _mousseron_ and the English ‘mushroom.’ It is curious that the Greek, Latin, and English ‘fungous’ terms have all been used in a sense reflecting on some of our species. The Greek _mucos_ represented a silly, stupid fellow, and the Plautus couples the fungi——‘soft-pated’——with the ‘fools,’ ‘stolid’ and ‘fatuous.’ In like manner in our own language, Bacon speaks of certain persons as ‘mushrooms and upstart weeds’ because of their sudden growth from a lowly origin. South, in one of his sermons, reflects on “mushroom divines who start up of a sudden,” and whose success is ‘not so good as to recommend their practice.’ Carrying out the same analogy, the late Albert Smith, if we recollect rightly, spoke of ‘stuck-up people’ as springing like mushrooms suddenly into notice, and, like them, from very questionable soil.

“One word as to the connection between fungi and what are called ‘fairy rings’ in our meadows. These fairy rings unfortunately lose all their poetry when it is known that they are simply produced by the growth of various kinds of fungi. The fungi start from a centre, owing to some peculiarity of the soil and decaying vegetable matter in it, and when they have exhausted the spot on which they originally sprang up, they enlarge their borders, as it were, and thus form circles, giving a darker tinge to the herbage affected by them. These rings increase in size annually, and thus they vary considerably in circumference. This is a prosaic but truthful explanation of the phenomenon which so often attracts the attention of children and puzzles the heads of older persons.”[43]

[Footnote 43: ‘Daily Telegraph.’]

In cases of poisoning by fungi, vomiting should be immediately induced by an emetic and tickling the fauces with the finger or a feather; after which a purgative clyster or a strong cathartic should be administered, with 1/2 to 1 fl. dr. of ether in a glassful of water or weak brandy. As an antidote, a solution of tannin, 1/2 dr., in water, 1-1/2 pint, or a decoction of 1/2 oz. of powdered galls, or of 1 oz. of powdered cinchona bark, in a like quantity of water, has been strongly recommended by M. Chansarel.

Alexis Soyer recommended the excellent method of cooking mushrooms by baking them under a glass or basin on toast, along with scalded or clotted cream, or a little melted butter, with one clove, and salt, pepper, &c., to taste. They take about 1/4 of an hour in a gentle oven or before the fire. When they are taken up, do not remove the glass for a few minutes, by which time the vapour will have become condensed and gone into the bread; but when it is, the aroma, which is the essence of the mushroom, is so powerful as to pervade the whole apartment.

=MUSK.= _Syn._ MOSCHUS (B. P., Ph. L., E., & D.), L. “A secretion deposited in a follicle of the prepuce of _Moschus moschiferus_, Linn.” (Ph. L.), an animal inhabiting the mountains of Eastern Asia. It is imported from Bengal, China, and Russia; and, latterly, from the United States of America. That known as TONQUIN MUSK is the most esteemed for its odour; but that from Russia is the only kind which reaches us in perfect bags, or which has not been tampered with. POD MUSK (MOSCHUS IN VESICIS) is the bag in its natural state, containing the musk. The average weight of one of the pods is about 6 dr.; that of the grain musk which it contains, about 2-1/2 dr.

_Pur_, _&c._ The musk of the shops is generally adulterated. Dried bullock’s blood or chocolate is commonly employed for this purpose, along with a little bone-black. The extent of these additions varies from 25% to 75% of the gross weight of the mixture. The blood is dried by the heat of steam or a water bath, then reduced to coarse powder, and triturated with the genuine musk in a mortar along with a few drops of liquid of ammonia. It is then either replaced in the empty pods, or it is put into bottles, and sold as grain musk. There are only three certain ways of detecting this fraud, viz.——by the inferiority of the odour, by an assay for the iron contained in the blood, or——by the microscope. Genuine musk often becomes nearly inodorous by keeping, but recovers its smell on being exposed to the vapour of ammonia, or by being moistened with ammonia water. The perfumers sometimes expose it to the fetid ammoniacal effluvia of privies for the same purpose.

Pure musk, by trituration or digestion with boiling water, loses about 75% of its weight, and the boiling solution, after precipitation with nitric acid, is nearly colourless. A solution of acetate of lead, and a cold decoction of galls, also precipitate the solution; but one of corrosive sublimate does not disturb it. The ashes left after the incineration of pure musk are neither red nor yellow, but grey, and should not exceed 5 to 6%. The Chinese appear to be the most skilful and successful adulterators of musk. One of the best solvents for musk is ether.

_Uses_, _&c._ Musk is chiefly employed for its odour. As a _medicine_ it is a powerful stimulant and antispasmodic, and is a valuable remedy in various diseases of a spasmodic or hysterical character, or attended with low fever.——_Dose_, 5 to 10 grains made into an emulsion.

=Musk, Factitious.= _Syn._ RESIN OF AMBER; RESINA SUCCINI, MOSCHUS ARTIFICIALIS, M. FACTITIUS, L. _Prep._ 1. Oil of amber, 1 fl. dr.; nitric acid, 3-1/2 fl. dr.; digest in a cold tumbler, and after 24 hours, wash in cold water the orange-yellow resinous matter which has formed, and carefully dry it.

2. (Elsner.) From oil of amber, 1 part; fuming nitric acid, 3 parts; as the last, but employing artificial cold to prevent any portion of the oil being carbonised.

_Obs._ Resin of amber smells strongly of musk, and is said to be antispasmodic and nervine. A tincture (TINCTURA RESINÆ SUCCINI) is made by dissolving 1 dr. of it in rectified spirit, 10 fl. dr., of which the dose is 1 fl. dr.; in hooping-cough, low fevers, &c.

Dr Collier mentions an artificial musk, prepared by digesting for 10 days nitric acid, 1/2 oz., on fetid animal oil, obtained by distillation, 1 oz.; then adding of rectified spirit, 1 pint, and digesting the whole for a month.

=MUSK SEED.= _Syn._ GRAINS D’AMBRETTE. The seed of _Abelmoschus moschatus_, or musk mallow. They are chiefly used for their odour, in perfumery, hair powder, coffee, &c.

=MUS′SEL.= See SHELL-FISH.

=MUST.= _Syn._ MUSTUM, L. The expressed juice of ripe grapes, before fermentation. When boiled to 2-3 dr. it is called CARENUM; when boiled to 1/2, it is called SAPA. On further concentration, it yields a species of granular sugar (grape sugar.)

=Must, Facti′′tious.= _Syn._ MUSTUM FACTITIUM, L. _Prep._ Dissolve cream of tartar, 3/4 oz., in boiling water, 7 pints; when cold, add of lump sugar, 2-1/2 lbs.; raisins (chopped small), 1/2 lb.; digest for 3 or 4 hours, strain through flannel as quickly as possible, and add of lemon juice, 1/2 pint.

=MUS′TARD.= _Syn._ SINAPIS, L. “The seed of _Sinapis nigra_ and _S. alba_.” (Ph. L.) “Flour of the seeds of _Sinapis nigra_, generally mixed with those of _Sinapis alba_, and deprived of fixed oil by expression.” (Ph. E.) “The flour of the seeds.” (Ph. D.) “The seeds of the _Sinapis nigra_ and _S. alba_ reduced to powder and mixed.” (B. P.) That of the shops is very frequently adulterated with wheat flour. When this is the case it does not readily make a smooth paste with water, but exhibits considerable toughness, and somewhat of a stringy appearance, especially when little water and much heat is employed. The common proportions taken by some grocers are——dried common salt, wheat flour, and superfine mustard, equal parts; with turmeric, to colour, and cayenne, q. s. to give it piquancy and fire.

_Uses_, _&c._ Pure flour of mustard is used in medicine, to make stimulating poultices, pediluvia, &c. As a condiment it is useful in torpor and coldness of the digestive organs. A few years since the use of mustard seed, by spoonfuls, _ad libitum_, was a common and fashionable remedy in torpor or atony of the digestive organs. The practice was a revival of that recommended by Dr Cullen; but it has now again sunk into disuse. Sir John Sinclair also approved of the use of mustard seed in this way, especially for the preservation of the health of the aged. (‘Lancet,’ Jan., 1834.) See POULTICES, &c.

=Mustard for the Table.= The common practice of preparing mustard for the table with vinegar, or still more, with boiling water, materially checks the development of those peculiar principles on which its pungency or strength almost entirely depends. To economise this substance, we should use lukewarm water only; and when flavouring matter is to be added to it, this is better deferred until after the paste is made. The following forms for ‘made mustard’ are much esteemed for their flavour:——

_Prep._ 1. Mustard (ground), 3-1/2 lbs.; water, q. s. to form a stiff paste; in 1/2 hour add of common salt (rubbed very fine), 1 lb.; with vinegar, grape juice, lemon juice, or white wine, q. s. to reduce it to a proper consistence.

2. To the last add a little soluble cayenne pepper or essence of cayenne.

3. (Lenormand.) Best flour of mustard, 2 lbs.; fresh parsley, chervil, celery, and tarragon, of each 1/2 oz.; garlic, 1 clove; 12 salt anchovies; (all well chopped); grind well together, add of salt, 1 oz.; grape juice or sugar q. s. to sweeten; with sufficient water to form the mass into a thinnish paste by trituration in a mortar. When put into pots, a red-hot poker is to be thrust into each, and a little vinegar afterwards poured upon the surface.

4. (MOUTARDE A L’ESTRAGON.) From black mustard seed (gently dried until friable, and then finely powdered), 1 lb.; salt, 2 oz.; tarragon vinegar, q. s. to mix. In a similar way the French prepare several other ‘mustards,’ by employing vinegars flavoured with the respective substances, or walnut or mushroom ketchup, or the liquors of the richer pickles.

5. (MOUTARDE SUPERBE.) Salt, 1-1/2 lb.; scraped horseradish, 1 lb.; garlic, 2 cloves; boiling vinegar, 2 galls.; macerate in a covered vessel for 24 hours, strain, and add of flour of mustard, q. s.

6. (Patent.) Black ginger (bruised), 12 lbs.; common salt, 18 lbs.; water, 15 galls.; boil, strain, and add to each gallon flour of mustard, 5 lbs.

=Mustard Leaves= (Rigollot’s) are made by spreading moistened mustard on paper, and drying.

=MUS′TINESS.= See MALT LIQUORS and WINES.

=MU′TAGE.= The term applied to the ‘matching’ of grape must to arrest the progress of fermentation. See ANTIFERMENT, MATCHES, &c.

=MUT′TON.= The flesh of sheep. That of the first quality is “between four and five years old; but at present it is rarely got above three, and often under two. The flesh ought to be of a darkish, clear, red colour, the fat firm and white, the meat short and tender when pinched, and it ought not to be too fat.” The flesh of the ‘Southdown wether’ is esteemed the finest flavoured. Mutton is one of the most wholesome of the ‘red meats,’ and in commercial importance is second only to beef. See MEAT.

=MY′COSE.= A peculiar variety of sugar, extracted by alcohol from ergot of rye. It crystallises in colourless prisms, and is distinguished from cane sugar by not reducing the acetate of copper, when boiled with a solution of that salt.

=MYLABRIS.= _Syn._ MYLABRIS CICHORII; CHINESE BLISTERING FLY. An insect found on the flowers of the succory plant in India and China. It is about an inch and a quarter in length; sheath-wings black, each presenting anteriorly two almost quadrate, brownish-yellow spots; behind these two brownish-yellow bands, each of which equals about one sixth of the length of the sheath-wings. Its vesicant properties are due to the presence of cantharidin.

Its physiological actions are the same as those of cantharides, except that it is said not to affect the kidneys when topically applied.

=MYRICIN.= The portion of beeswax which is least soluble in alcohol, and saponified with difficulty.

=MYRISTIC ACID.= HC_{14}H_{27}O_{2}. A monobasic fatty acid, obtained by the saponification of myristin. It melts at 120° Fahr.

=MYRIS′TIN.= C_{45}H_{86}O_{6}. _Syn._ SERICINE. The white, solid portion of the expressed oil of nutmegs, which is insoluble in cold alcohol. See MYRISTIC ACID.

=MYROLES.= In French _pharmacy_, solutions of oleaginous or resinous substances in the volatile oils.

=MYRON′IC ACID.= HC_{10}H_{18}NS_{2}O_{10}. Bussy has given this name to an inodorous, bitter, non-crystallisable acid, obtained by him from black mustard, in which it exists as myronate of potassium. It is soluble in water and alcohol.

=MYROSIN.= _Syn._ EMULSIN OR BLACK MUSTARD. A name given by Bussy to a peculiar substance, soluble in water, and which possesses the power of converting myronic acid, in the presence of water, into the volatile oil of mustard seed.

=MYROSPERMIN.= The name given by Richter to the portion of the oil of balsam of Peru, which is soluble in alcohol.

=MYROX′ILIN.= The name given by Richter to the portion of the oil of balsam of Peru which is insoluble in alcohol. By oxygenation it forms myroxilic acid.

=MYRRH.= _Syn._ MYRRHA (B. P., Ph. L., E., & D.), L. “Gum resin exuded from the bark of _Balsamodendron myrrha_.” (B. P., Ph. L.)

_Pur._——1. Triturate a small quantity of the powder of the suspected myrrh with an equal amount of chloride of ammonium, adding water, gradually; if the whole is readily dissolved, the myrrh is genuine; otherwise it is sophisticated with some inferior substance. (Righini.)——2. When incinerated it should not leave more than 3-1/2 to 4% of ashes.

_Uses, &c._ Myrrh is a stimulating aromatic bitter and tonic, and is given in several diseases accompanied by relaxation and debility; especially in excessive secretions from the mucous membranes, and in disorders of the digestive organs. _Externally_, as an ingredient in dentifrices and rashes, in caries of the teeth, spongy and ulcerated gums, &c.——_Dose_, 10 to 30 gr.; either alone or combined with aloes or chalybeates.

=NAILS (The)= should be kept clean by the daily use of the nail-brush and soap-and-water. After wiping the hands, but whilst they are still soft from the action of the water, the skin, which is apt to grow over the nails, should be gently loosened and pressed back, which will not only preserve them neatly rounded, but will prevent the skin cracking around their roots (agnails, nail-springs), and becoming sore. The free ends or points of the nails should be pared about once a week; and biting them should be particularly avoided, as being at once destructive to their beauty and usefulness. “The (free) edge of the scarf-skin should never be pared, the surface of the nail never scraped, or the nails cleaned with any instrument whatever saving the nail-brush.” (Eras. Wilson.)

The consequences of wearing a shoe that is obviously too short for the foot are thus described by the above authority:——“In this case Nature gives us warning, by means of her agent, pain, that such a proceeding is contrary to her laws. We stop our ears, and get accustomed to the pain, which, perhaps, is not severe, and soon goes off; the shoes get a scolding for their malice, and we forget all about it for a time. But does Nature check her course to suit the convenience of thoughtless men? No, no. In a short time we find that the nail, intercepted in its forward course, has become unusually thick and hard, and has spread out so much upon the sides, that it is now growing into the flesh, and so makes a case for the doctor. Or, perhaps, the continuance of pressure may have inflamed the sensitive skin at the root, and caused a sore and painful place there. And instances are by no means infrequent in which the power of production of the nail at the root becomes entirely abrogated, and then it grows in thickness only.”

When the nails are stained or discoloured, a little lemon juice, or vinegar-and-water, is the best application. Occasionally, a little pumice-stone, in impalpable powder, or a little ‘putty powder,’ may be used along with water and a piece of soft leather or flannel for the same purpose. The frequent employment of these substances is, however, injurious to the healthy growth of the nail.

=NANKEEN′.= The coloured cotton cloth which bears this name was originally brought from Nankin, the ancient capital of China, and was prepared from a native cotton, of a brownish-yellow hue. It is now successfully imitated in England, and at the present time the English manufacturers supply the Canton market. In this country the colour is generally given to the cloth by successive baths of sulphate of iron and crude carbonate of soda or lime water.

=NANKEEN DYE.= The liquid sold under this name in the shops is a solution of annotta. It is employed to dye white calicoes of a nankeen colour; but chiefly to restore the colour of faded nankeen clothing.

=NAPH′THA.= _Syn._ MINERAL NAPHTHA; NAPHTHA, L. A name given to the limpid and purer varieties of PETROLEUM (which _see_), or ROCK OIL, which exudes from the surface of the earth in various parts of the world.

_Prop._ Naphtha possesses a penetrating odour and a yellow colour, but may be rendered colourless by distillation; it usually begins to boil at a temperature of about 180° Fahr., but, being a mixture of several different hydrocarbons, it has no fixed boiling-point; it is very inflammable; it does not mix with water, but imparts to that fluid its peculiar taste and smell; mixes with alcohol and oils, and dissolves sulphur, phosphorus, camphor, iodine, most of the resins, wax, fats, and spermaceti; and forms with caoutchouc a gelatinous varnish, which dries with very great difficulty.

_Pur._ Mineral naphtha is very frequently adulterated with oil of turpentine, a fraud which may be detected by——1. The addition of some oil of vitriol, which will, in that case, thicken and darken it.——2. Hydrochloric acid gas passed through the liquid for an hour, will occasion the formation of hydrochlorate of camphine, either at once or after a few hours’ repose, even if only 5% of oil of turpentine is present. (Dr Bolley.)——3. If a few grains of iodide of potassium and a little water are rubbed with the suspected sample, the colour of the water should continue unchanged; the presence of 1/300th part of oil turpentine will cause it to assume a red or orange colour. (Saladin.)

_Uses._ Naphtha is chiefly employed for the purposes of illumination, as a solvent for india rubber, and in the preparation of a very superior black pigment. It has been highly spoken of as a remedy for cholera, by Dr Andreosky, a Russian physician. See PETROLEUM, and _below_.

=Naphtha, Coal-tar.= _Syn._ NAPHTHA, COAL N. A mixture of volatile hydrocarbons, obtained by distilling coal-tar. It is one of the first products which comes over, and flows from the still as crude coal naphtha. To obtain rectified coal naphtha, this crude liquid is distilled, and the product agitated with 10% of concentrated sulphuric acid; when cold, the mixture is treated with 5% of peroxide of manganese, and the upper portion is submitted to further distillation. The specific gravity of this purified product is ·850. It is extensively used as a solvent of caoutchouc, and other allied substances, also of resins for the preparation of varnishes. By repeated purification and fractional distillation, benzol, the chief and most important constituent of coal naphtha, is obtained. See BENZOL.

=Naphtha, Wood.= See PYROXYLIC SPIRIT.

=NAPH′THALIN.= C_{10}H_{9}. _Syn._ NAPHTHALINE, NAPHTHALENE. A white crystallisable, odorous, volatile substance, obtained from coal-tar.

_Prep._ The last portion of the volatile oily product is collected separately, and allowed to repose, when crude naphthalin separates in the solid state. By pushing the distillation until the residuum in the still begins to char, a further portion of dark-coloured naphthalin may be obtained. It is purified by resublimation a second, or even a third time.

_Prop., &c._ Soluble in alcohol and ether; slightly soluble in boiling water; melts at 176° Fahr.; boils at 412°; highly inflammable, burning with a red and smoky flame; with sulphuric acid, it unites to form sulpho-naphthalic acid. By the action of nitric acid upon naphthalin, numerous substances may be formed, the most interesting being nitro-naphthalin. Naphthalin has lately been extensively employed as a stimulating expectorant.——_Dose_, 5 to 20 gr.; or, preferably, 1/2 gr., frequently. _Externally_, made into an ointment, in dry tetters, psoriasis, &c. 30 gr. may be mixed with 1 oz. of lard.

=NA′PLES YEL′LOW.= See YELLOW PIGMENTS.

=NAR′CEIA.= C_{23}H_{20}G_{9}. _Syn._ NARCEINA, NARCEIA. A peculiar substance discovered by Pelletier in opium. It is obtained from the aqueous solution of opium, after it has been freed from morphia, and narcotina, by ammonia, by adding to it hydrate of lime, or preferably, baryta. On boiling the filtered solution, to expel the ammonia, and evaporating the liquid, crystals of narceine are gradually deposited. It may be purified by solution in hot alcohol and recrystallisation.

_Prop., &c._ White, silky, acicular prisms; neutral; inodorous; bitter; pungent; soluble in 375 parts of water at 60°, and in 330 parts at 212° Fahr.; insoluble in ether; does not neutralise the acids, and is destitute of basic properties. It is distinguished from morphia by its easier fusibility (190°), and by forming a blue liquid with the dilute mineral acids, which on gradual dilution changes to violet and rose red, and ultimately becomes colourless. It does not strike a blue colour with ferric chloride, like morphia, but forms a blue compound with iodine, which is decomposed by boiling water. It appears to be inert, and has not been applied to any useful purpose.

=NAR′COTICS.= _Syn._ STUPEFACIENTS; NARCOTICA, STUPEFACIENTIA, L. Medicines which produce drowsiness, sleep, and stupor. In small doses, narcotics mostly act as stimulants, but in larger ones they produce calmness of mind, drowsiness, and torpor; and in poisonous doses, delirium, coma, and death. The general objects in the administration of these agents are the production of sleep and the alleviation of pain. Their action is modified to a greater degree by idiosyncrasy and habit than that of, perhaps, any other class of medicines. Hence the care necessary in their administration. Alcohol, camphor, chloroform, chloral hydrate, ether, foxglove, hemlock, henbane, morphia, opium, and tobacco, are narcotics.

=NAR′COTINA.= C_{22}H_{23}NO_{7}. _Syn._ NARCOTINE, L.; SEL D’OPIUM, MATIÈRE DE DEROSNE, Fr. A peculiar crystalline substance, found by Derosne in opium, and on which its stimulant property was at first supposed to depend.

_Prep._ 1. From opium exhausted of soluble matter by cold water, by treating it with water acidulated with acetic or hydrochloric acid, filtering, neutralising, with ammonia, and dissolving the washed precipitate in boiling alcohol; the narcotine is deposited as the liquid cools, and may be purified by solution in ether.

2. By acting on opium, previously exhausted by cold water, with ether.

_Prop., &c._ White, inodorous, fluted, or striated prisms; neutral to test paper; insoluble in cold water; sparingly soluble in boiling water; freely soluble in boiling alcohol and in ether. It is only feebly basic.

Narcotine is distinguished from morphia by its insipidity, solubility in ether, insolubility in alkalies, giving an orange tint to nitric acid, and a greasy stain to paper when heated on it over a candle. Another test for narcotina, said by Orfila to be characteristic, is to add to a little of the suspected substance a drop or two of oil of vitriol, and then to add a very small fragment of nitrate of potassium; the liquid speedily acquires a deep blood-red colour if narcotina is present. Morphia treated in the same way strikes a brown or olive-green colour.

_Obs._ The physiological action of narcotina is differently stated by different authorities. 1 gr. of it, dissolved in olive oil, killed a dog in 24 hours: but 24 gr. dissolved in acetic acid were given with impunity. (Magendie.) In the solid state it is inert; 120 gr. at a dose scarcely produce any obvious effects. (Bally.) Scruple doses have been given without injury. (Dr Roots.) It has been recently proposed as a substitute for quinine in the cure of agues. For this purpose the sulphate or hydrochlorate is preferable. 200 cases of intermittent and remittent fevers have been thus successfully treated in India. (Dr O’Shaughnessy.)——_Dose_, 3 to 10 gr., as an antiperiodic sedative, &c.

Turkey opium contains about 1%, and East Indian opium about 3%, of narcotine.

=NA′TRIUM.= See SODIUM.

=NA′TRON.= Native carbonate of soda.

=NAU′SEA.= See SICKNESS.

=NAU′SEANTS.= _Syn._ NAUSEANTIA, L. Substances which induce an inclination to vomit, without effecting it. See EMETICS.

=NAVEL, Starting of.= To remedy this, take a slice of cork about the circumference of a shilling, and a little thicker; and having covered the projecting navel with a small circular piece of clean, soft linen, place the cork on the linen, strapping it into position by means of cross strips of _white_ sticking plaster (simple lead plaster) over which the usual roller is to be adjusted. Be careful to have the plaster of sufficient length, and to see that it adheres tightly to the skin.

=NEC′TAR.= The fabled drink of the mythological deities. The name was formerly given to wine dulcified with honey; it is now occasionally applied to other sweet and pleasant beverages of a stimulating character. The following LIQUEURS are so called:——

_Prep._ 1. Chopped raisins, 2 lbs.; loaf sugar, 4 lbs.; boiling water, 2 galls.; mix, and stir frequently until cold, then add 2 lemons, sliced; proof spirit (brandy or rum), 3 pints; macerate in a covered vessel for 6 or 7 days, occasionally shaking, next strain with pressure, and let the strained liquid stand in a cold place for a week to clear; lastly, decant the clear portion, and bottle it.

2. Red ratafia, 3 gall.; oils of cassia and caraway, of each 25 drops (dissolved in); brandy, 1/2 pint; orange wine, 1 gall.; sliced oranges, 6 in no.; lump sugar, 2 lbs.; macerate for a week, decant and bottle. See ARRACK (Factitious.)

=NE′GUS.= A well-known beverage, so named after its originator and patron, Colonel Negus. It is made of either port or sherry wine, mixed with about twice its bulk of hot water, sweetened with lump sugar, and flavoured with a little lemon juice and grated nutmeg, and a small fragment only of the yellow peel of the lemon. The addition of about 1 drop of essence of ambergris, or 8 or 10 drops of essence of vanilla, distributed between about a dozen glasses, improves it.

=NEPEN′THE.= A drink calculated to banish the remembrance of grief. In the “Odyssey” Homer describes Helen as administering it to Telemachus. Nothing is known respecting the composition of the ancient nepenthe. The name is applied to a preparation of opium by many old writers, and is now employed by a Bristol firm to designate a preparation resembling in all essential points Battley’s ‘LIQUOR OPII SEDATIVUS,’

=NER′VOUSNESS.= The indescribable derangement of health, and the complication of disagreeable sensations which are popularly described under this name, quite as much deserve the serious attention of both patient and physician as any other affection to which the human frame is liable. Although, in itself, not a definite disease, it is indicative of the vital system being out of order, that its energies are failing or overtasked, and that the functions of some of its organs are languidly or imperfectly performed. This condition, if not removed, may gradually lead to the development of actual disease, and imperil life if the conditions whereon it is dependent be not detected and subdued.

The _treatment_ of nervousness consists mainly in restoring the healthy action of the stomach and bowels, and in the use of proper exercise, especially in the open air. The stomach should not be overloaded with indigestible food, and the bowels should be occasionally relieved by the use of some mild aperient. Mental as well as bodily relaxation should be sought, and the pleasures without the vices of society should be indulged in as discretion and inclination may direct. Abernethy’s injunction to a nervous and dyspeptic lady, “Dismiss your servants, madam, and make your own beds,” should be recollected by all, and may be taken as a proof of the importance that eminent surgeon attached to exercise; his advice to the indolent and nervous dyspeptic should not be forgotten, “Live on sixpence a day——and earn it.” See EXERCISE, FLATULENCE, HYPOCHONDRIASIS, HYSTERIA, INDIGESTION, &c.

=NESSLER’S TEST for ammonia, &c.= This, the most delicate test for ammonia, was devised by Nessler. It is prepared by saturating a solution of iodide of potassium with the biniodide of mercury, and then adding a weak solution of hydrate of sodium. The addition of a few drops of this solution, to one containing ammonia, produces a yellowish tint when only a trace of ammonia is present, but a dark brown precipitate when the ammonia is present in larger quantity. The composition of the precipitate may be represented thus:——NHg_{2}I. A modification of this test is applied to the detection of wood spirit in common alcohol. A dilute solution of the iodides in question in pure alcohol is formed, in the proportion of 2 or 3 gr. of the salts to 100 c.c. of alcohol. About 4 c.c. of the suspected alcohol are taken, to which are added 2 or 3 drops of the test solution, a few drops of alcoholic ammonia, and, lastly, a little alcoholic potash; if wood spirit be present, the solution will remain clear, but if the alcohol be pure, the characteristic reddish brown precipitate will appear. The precipitate is soluble in acetone, which is always present in wood spirit.

Professor Wanklyn gives the following formulæ for the preparation of the Nessler test:——Mercuric chloride in powder, 35 grammes; iodide of potassium, 90 grammes; water, 1-3/4 litres; heat gently till dissolved (say 20 minutes) in a large basin. Then add of stick caustic potash, 320 grammes, and 50 c.c. of saturated solution of mercuric chloride. The above will be ready for use in 2 hours, and gives maximum colour in 3 minutes.

=NESTS, EDIBLE.= These dietetic curiosities, which are esteemed as great gastronomic luxuries by the Chinese, are formed by several species of swallows frequenting the Indian Seas. The so-called nests chiefly abound in Java, Borneo, and the Celebes, being found in the caverns both inland and on the sea-shores of those islands.

They are not in reality birds’ nests, but merely supports, by which the bird is enabled to sustain and also to attach its nest to the rock. The nests themselves consist of grass, leaves, and seaweed; the latter of which substances it was for a long time erroneously considered formed the esculent; whereas it is the support which exclusively constitutes this Eastern table luxury.

This, in great part, consists of a peculiar mucus, of a gelatinous nature, which it has been ascertained the bird secretes and discharges from its mouth in large quantities. The Chinese mostly use it in the form of soup, and believe it to be possessed of considerable nutrient power. As many as 8,400,000 of edible nests are said to be annually imported into Canton. “The finest and whitest kind sells for £5 or £6 the lb.; but it requires about fifty nests to make up one pound. The brackets or supports are moved three times, the best being obtained in July and August.”[44]

[Footnote 44: Church.]

=NET′TLE RASH.= See RASH.

=NEURAL′GIA.= Literally, pain in a nerve. “Various parts of the body are liable to be affected with excruciating pain, which is quite independent of any inflammation of the part, and which may often be traced in the course of the nerves.” These affections constitute neuralgia. One of the most distressing forms of this disease is FACIAL NEURALGIA or TIC DOULOUREUX (NEURALGIA FACIALIS), which, when it assumes a marked intermittent character, is popularly known as ‘FACE AGUE,’ Sometimes it attacks the nerves of the female breast; or those of the hand, feet, hip, or loins, in which cases it is often confounded with acute rheumatism of those parts, occurring towards the inner extremity of the eyebrow and extending over the forehead, it is known as “Brow-ague.”

The treatment, when neuralgia is symptomatic of any other affection, must be directed to the primary disease. When it is idiopathic, or an independent affection, powerful tonic medicines and powerful local counter-irritation are generally found the most successful remedies. Of tonics, carbonates of iron and bark (both in very large doses) are generally preferred; the last more particularly when the affection is of an intermittent kind. As a counter-irritant, caustic ammonia has been much relied on. When all other means fail, a current of mild streaming electricity through the part will often give immediate relief. In the present day quinine in large doses is much depended on, although the affection should not present the intermittent type.

_Plain Advice to the Neuralgic by a Family Doctor._[45]——Here, reader, are two facts, which are patent to every thinking medical man: first, this agonising complaint, called neuralgia, is very much more common or prevalent in our day than it was in the days of our forefathers; and secondly, those among us who are most apt to suffer from it are they who live in luxury, or who live too fast, and neglect to keep their bodies up to the proper health-pitch. The poor, too, are often afflicted in the same way, and those who are much confined in workshops, and badly ventilated factories. From this it is not difficult to perceive a lesson may be learned.

[Footnote 45: The article entitled “Plain Advice to the Neuralgic,” which appeared in ‘Cassell’s Family Magazine,’ is so good that we reprint it verbatim.]

Little need is there to describe the symptoms of neuralgia, whether it takes the form of tic douloureux or faceache, hemicrania or half headache (sometimes, but wrongly, called sun-pain), or sciatica, in which the pain follows the course of a nerve running down the back of the leg, even at times as far as the toes. The pain when fully established is of a terribly acute kind, and indescribable burning and shooting——torture, in fact. It generally comes on without any warning at all, in one sharp twinge, which soon recurs and keeps on increasing, till the poor patient is half distracted, and his pale anxious face is beaded with perspiration.

Of the three kinds of neuralgia, the most common by far is tic, or faceache. This pain seems to ‘come out,’ as I have heard patients describe it, from a spot between the ear and temple, and spread itself over one side of the face, adown the jaws along one side of the nose, and into the eye itself. The fits of pain seem at times induced by the most trifling causes, such as a sudden start, a loud, quick sound, as the slamming of a door, or the slightest draught of cold air, a mouthful of hot tea or cold water. Sometimes the patient will get ease if he keeps in bed, with the face entirely buried in warm soft flannel, but contact with the pillow will at once induce a paroxysm. Sleep banishes the pain entirely for the time, or perhaps altogether, if the slumber has been natural, and not induced by weakening, enervating narcotics.

Now let us see for a moment what are the usual causes of neuralgia. If we know these, it will assist us materially in laying down rules for the general treatment of the complaint. And here let me premise that some cases are incurable, because they depend upon pressure by tumours of some kind at the root of the nerve, maybe a bit of bone growing into it. For remember the nerves are extremely sensitive if pressed upon directly. A kinder-hearted man than Professor L——, of Aberdeen, or ‘Sandie’ as he was familiarly termed, never lived; but he used to tell us students, “Gentlemen, in cutting down upon an artery, in one of the extremities, you will often find the artery, the vein, and the corresponding nerve lying in juxtaposition. You can easily tell the vein, but you may be puzzled to know which is nerve and which artery; give one of them, then, a slight pinch with the forceps——if it is the former, oh! won’t the patient holloa! but if he doesn’t holloa, go on, tie away.”

And I have often seen this put in practice with the very happiest results, so far as the operator was concerned. I merely mention this to prove to you that pressure on the root of a nerve may cause an incurable form of neuralgia. But do not think that I wish to frighten you! I therefore hasten to tell the perhaps afflicted reader, that these cases are very rare indeed, and that the large majority of those who suffer from the malady may be cured for the time, and the disease even prevented from returning.

I said that very often neuralgia gave no warning, but came on suddenly, but it more often comes on gradually, and is preceded by some derangement of the general health, such as indigestion. From this fact, again, the wise may take a hint.

I do not say that strong men with robust constitutions never take neuralgia, but all my experience, and that I believe of nearly all medical men, go to prove that it is more frequently an accompaniment of a weakened frame of body, with a nervous system below par. This may have been occasioned by bodily fatigue combined with want of sleep, anxiety of mind, worry, &c., or from debility from whatever cause. But I must not forget to say that indigestion is a frequent cause, and excess in eating and drinking combined with late hours in hot rooms. Another hint, please, reader. Foul air, especially living in malarious districts, will also bring on neuralgia, and in this case the attacks are generally of a periodical kind. The great majority, however, of the cases of neuralgia which come under the notice of the practitioner, are caused by decayed teeth. And this fact gives us hint number three.

Sciatica cases are at times exceedingly distressing. I shall just mention one, which I cured not long since; and we may learn something from it because the cure was so simple. A gentleman, thirty-two years of age he was, spare but wiry; from errors in diet, I elicited, he had become troubled with indigestion and heartburn, which lasted for months; and, moreover, he had quite his own share of that heart-eating canker, care. For the heartburn he was in the habit of swallowing large quantities of the bicarbonate of soda. Now it is well known that antacids, although they may palliate fits of indigestion, cannot cure them; and, moreover, the constant use of an antacid like soda never fails to bring on a state of debility and poverty of blood. In the present case the pains in the limb were almost constant, combined with stiffness of the muscles, which necessitated the use of a staff in walking. At about three or four o’clock every morning there were paroxysms of the most terrible agony, during which the patient would leave his bed because, he said, “it wasn’t level,” and, rolled in a rug, lie at full length on the floor, bathed in pain-induced perspiration. It was no wonder he was glad to take that dangerous narcotic, hydrate of chloral, to give him quiet nights. But this only reduced his system more and more, and gave the enemy a stronger hold thereon. When I saw him he had been suffering thus for two months, and was indeed in a pitiable plight. But giving up both the chloral and the soda, going for change of air, using some simple tonic, and being careful in his diet, worked wonders for him. The sciatica left him in one week, and in six weeks he was well and hearty.

One of the most distressing things in connection with neuralgia is the length of time it sometimes lasts, and its habit of returning periodically, without giving, perhaps, any warning of its approach. The depression, too, of the nervous system which it effects is very great; even the mind to some extent suffers; the patient becomes timid and irritable, while at times even the muscles waste. The sufferer, if the complaint continues long, seems positively to age under it. That he soon recovers strength and spirits when the enemy has been driven from his stronghold, is only a proof of the recuperative power of nature in our systems, so long as youth or middle age is on our side.

Some ancient physician has said that no one thinks of taking care of his health until death stares him in the face. There is one exception, however: people very rarely die directly from neuralgia, unless it be that dreadful form of it called angina pectoris, or heart-cramp; but so great is the pain and torture from tic douloureux or sciatica, that sufferers therefrom are glad and willing to do anything that may present some hopes of relief.

The patient, then, who wishes to recover from this disease must first try to find out the cause of it, in his or her particular case. Is the digestion good? are the teeth good? is the health below par? are the spirits buoyant or the reverse? is the kind of life led that which seems to conduce to health and longevity?——these are questions which he had better put to himself and think well over before commencing any treatment except the simple means of local relief which I shall presently mention; for, depend upon it, whatsoever tends to place the system below par opens the door for the cruel foe’s entrance. And the converse is likewise true.

If you, then, suffer from tic douloureux, see, first and foremost, that it does not arise from caries of the teeth. Only a dentist can find this out for you, for a tooth may be sound enough to appearance, and yet decayed within. Often the removal of one or two teeth will effect, in an hour, the complete cure of a case that has been going on for months.

The treatment for neuralgia may be fitly divided into the topical, or that which gives relief at once, without reference to permanent cure, and the constitutional, or that which tends to remove the cause and prevent any recurrence. I shall mention the former of these first. Probably that which gives the greatest relief is the subcutaneous injection of morphia; but as this tiny but comforting operation can only be performed by some one with skill, I pass it by, and tell you of the great good that may be done by twice a day smearing the track of the nerve with the aconitine ointment; only remember, it must not be applied to an abraded surface. When it can be borne, alternate douches of hot and cold water sometimes give relief, and rubbing or shampooing the parts for some length of time may result in good.

But if the pain is at its worst, and immediate relief is needed, the inhalation of or smelling at a vial of chloroform will act like a charm. Take first a little good Scotch whiskey, with from 20 to 40 drops of the spirit of ether in it; then have, not one sniff, but two or three good sniffs at the vial of chloroform. It will not make you insensible, but it will scare away the pain. I often do good by administering one large dose of quinine. I am rather chary of advising you, however, to try it, because ten or fifteen grains of this invaluable medicine may work injury if either head or heart is easily affected.

People often complain of what they call rheumatism in the jaw, where probably the whole of the teeth in one side, not one more than another, are affected. Now the drug called sal ammoniac (chloride of ammonium) is almost a specific for this kind of faceache. It strikes me I have recommended this before——probably in my paper on the teeth——however, it will bear repeating. The dose is half a dram three or four times a day, but if it doesn’t do good after the fourth or fifth dose, it may be stopped. It is well worth a trial, and is safe.

Neuralgia and rheumatism are at times mysteriously allied, and, did space permit, I could tell you of some very strange cures effected by the use of the dumb-bells——first, I think, recommended by Dr Arnott. When the pain comes on, the patient has recourse to these; and whether it is the indomitable power of will or the effect on the circulation I know not——all I know is, it often scares the tic away, and that is something.

Nothing probably gives more certain relief in cases of sciatica than a small blister, not bigger than a penny-piece, just over the spot where the nerve seems to come out, _i. e._ where the pain begins, and afterwards dusting not more than half a grain of morphia on the raw surface. And now for constitutional remedies. I will not allow any patient of mine to cuddle and fondle himself and his neuralgia over the fire or in bed one hour longer than is necessary. The mind has a wonderful effect on nervous ailments, and by letting it dwell on them you assuredly increase them; besides, the body is under par, exercise is needed, and pure air and many things besides; and therefore I prescribe activity, to begin with, not senseless walk-taking, but healthy exercise-with-a-purpose.

Medicine must not be neglected; but I assure you, unless you not only take plenty of exercise, regulate your diet, and in some way alter for the better your usual mode of life, it will just be as well, if not better, to pour the medicine down the nearest rat’s hole. That may be a plain way of putting it, but it is very true notwithstanding. Now, I think in most cases an occasional mild purgative will do good, for tonics should never be taken unless the bowels are regular; and as the liver is at times just a _little_ to blame, a claret-glassful of Friedrichshall water may be taken twice a week with benefit. Your tonic, unless there be great fulness of blood, had better be an iron one, combined with quinine, which any chemist will compound you. Tell him you want the tincture of iron, and a little dilute hydrochloric acid, in a quinine mixture. Probably he will say the citrate of iron and quinine is better (it is more easily compounded), and then it will be for you to consider whether you will be advised by him or by your ‘Family Doctor.’ Here is a beautiful wee mixture, which you can compound for yourself, and the dose of which is a teaspoonful in a little water 3 times a day:——Take 2 oz. of tincture of quinine, 1/2 oz. of tincture of ginger, and the same quantity of pure glycerin, and mix. The following is a capital tonic to be taken after an attack of neuralgia and continued some weeks:——Liquor arsenicalis hydrochlorici, 100 drops; quinine, 30 gr.; elixir of vitriol, 2 dr.; ginger syrup, 3 oz.; mix. And the dose is a teaspoonful after every meal in a drop of water. When mentioning sal ammoniac, I ought to have said that in those cases where good is done——and they are very many——whenever the pain is gone, you should reduce the dose to 10 or 15 gr. thrice a day for a week. In some cases of sciatica, where the subject is a gouty or rheumatic one, good is done by a course of iodide of potassium in combination with tonics.

As for food, the more nourishing it is the better——good meat, plenty of eggs and milk, &c., and perhaps a little brandy and Apollinaris water.

Give up tea and coffee for a time, and use cocoa; the less oily kind is the best. My advice for the prevention of the return of neuralgia may be summed up in a few substantives——air, exercise, regularity, temperance, tonics, cocoa, and cod-liver oil.

=NEUTRALISA′TION.= The admixtures of an alkali or base with an acid in such proportions that neither shall predominate. A neutral compound neither turns red litmus paper blue, nor blue litmus paper red.

=NEUTRALISING PROPORTIONS, Table of.=

_Table of the Neutralising Proportions of some of the Acids and Alkaline Carbonates omitting minute fractions. The best commercial preparations must be used._

---------------------------------------------------------------------------------------- | | || |Bicarb. of| |Carbonate| Sesqui- | Bi- Tartaric|Citric |Lemon ||Cr. Carb.| Soda and |Bicarb. of| of |carbonate | carbonate Acid. | Acid. |Juice.||of Soda. | Carb. of | Potash. |Magnesia.| of | of | | || | Potash. | | | Ammonia. | Ammonia. --------+-------+------++---------+----------+----------+---------+----------+--------- Grs. | Grs. | ʒ || Grs. | Grs. | Grs. | Grs. | Grs. | Grs. 10 | 9-1/4| 2-1/6|| 19 | 11 | 13-1/2 | 6-1/2 | 8-1/4 | 10-1/2 10-3/4| 10 | 2-1/3|| 20-1/2| 12 | 14-1/2 | 7 | 8-1/2 | 11-1/2 13 | 12 | 2-4/5|| 25 | 14-1/2 | 17-1/2 | 8-1/4 | 10 | 13-1/2 15 | 14 | 3-1/4|| 29 | 17 | 20-1/3 | 9-1/2 | 12 | 16 15-1/2| 14-1/2| 3-1/3|| 30 | 17-1/4 | 21 | 10 | 12-1/4 | 16-1/2 18 | 17 | 4 || 34-1/2| 20 | 24-1/4 | 11-1/2 | 14 | 19 20 | 18-1/2| 4-1/3|| 38-1/2| 22-1/3 | 27 | 12-3/4 | 15-1/2 | 21 20-1/2| 19 | 4-1/2|| 40 | 23 | 27-1/2 | 13 | 16 | 21-1/2 26 | 24 | 5-1/2|| 50 | 29 | 35 | 16-1/2 | 18-1/4 | 27 27 | 25 | 5-5/6|| 52 | 30 | 36 | 17 | 21 | 28-1/2 32 | 30 | 7 || 61 | 36 | 43 | 20-1/2 | 25 | 33-1/2 36 | 33-1/2| 7-5/6|| 69 | 40 | 48-1/2 | 23 | 28 | 38 47 | 44 |10-1/4|| 90 | 52-1/2 | 63 | 30 | 37 | 49-1/2 52 | 48-1/2|11-1/3|| 100 | 58 | 70 | 33 | 41 | 55 62 | 58 |13-1/2|| 120 | 69 | 84 | 40 | 49 | 65-1/2 73 | 68 |15-5/6|| 140 | 82 | 98 | 46-1/2 | 57 | 77 75 | 70 |16-1/4|| 144 | 84 | 101 | 48-1/2 | 59 | 79 90 | 84 |19-1/2|| 172 | 101 | 121 | 57-1/2 | 71 | 94-1/2 92 | 86 |20 || 177 | 103 | 124 | 59 | 72 | 97 100 | 93 |21-2/3|| 192 | 112 | 134 | 64 | 78 | 105-1/2 108 |100 |23-1/3|| 206 | 120 | 145 | 69 | 84 | 113 180 |168 |39-1/5|| 344 | 202 | 242 | 115 | 141 | 190 -----------------------------------------------------------------------------------------

=NEW BERLIN SANITARY LIQUEUR——Gesundheits-Liqueur, neuer Berliner= (Apotheker Emil Trotz). An unpleasantly-tasting bitter spicey schnapps, containing 18 per cent. of sugar. Leaves an after-taste of aloes. (Hager.)

=NICK′EL.= Ni. _Syn._ NICKELIUM, L. A metal obtained from kupfernickel, a native arsenide of nickel found in Westphalia; also from nickel speiss, an impure arsenio-sulphide of nickel left after the manufacture of cobalt blue from its ores.

_Prep._ The powdered ore is roasted first by itself, and next with charcoal powder, until all the arsenic is expelled, and a garlic odour ceases to be evolved; the residuum is mixed with sulphur 3 parts, and potassium hydrate, 1 part, and the compound is melted in a crucible with a gentle heat; the fused mass when cold, is reduced to powder, edulcorated with water, dissolved in sulphuric acid mixed with a little nitric acid, and precipitated with potassium carbonate; the precipitate (nickelous carbonate) is washed, dried, mixed with powdered charcoal, and, lastly, reduced by the heat of a powerful furnace.

When nickel predominates in the ore, after the arsenic, iron, and copper have been separated, ammonia is digested in the mixed nickelous and cobaltous oxides, and the resulting blue solution, after dilution with boiled pure water, is treated with potassium hydrate until the colour disappears, when the whole is put into an air-tight vessel, and set it aside for some time. The powder (nickelous hydrate) which subsides, after edulcoration, is mixed with charcoal, and reduced by fusion in a crucible containing some crown glass.

On the small scale, for chemical purposes, pure nickel is best obtained by moderately heating nickelous oxalate in a covered crucible lined with charcoal.

_Prop._ White; hard; malleable; magnetic; capable of receiving the lustre of silver; sp. gr., when hammered, about 8·82; fusibility between that of manganese and iron; it is not oxidised in the air; and is little attacked by dilute acids unless when nitric acid is present; this last acid dissolves it freely. With the acids, &c., it forms numerous compounds, most of which may be prepared by the direct solution of the carbonate. A specimen of the metal reduced from the pure oxide in a current of hydrogen was beautifully white and silvery; its sp. gr. was 8·575, and it was almost as soft as copper.

_Tests._ The salts of nickel in the anhydrous state are for the most part yellow; when hydrated, green,——and furnish solutions possessing a pale green colour. Solutions of its salts exhibit the following reactions:——Alkaline hydrates give a pale apple-green precipitate, insoluble in excess, but soluble in a solution of carbonate of ammonium, yielding a greenish-blue liquid. Ammonia gives a similar precipitate, soluble in excess, yielding a deep purplish-blue solution. The presence of ammonium salts or free acids interferes with this reaction. Cyanide of potassium produces a green precipitate, soluble in excess, forming an amber-coloured liquid, which is reprecipitated by hydrochloric acid. This last precipitate is scarcely soluble in excess of the acid in the cold, but readily so upon boiling the liquid. Ferrocyanide of potassium gives a greenish-white precipitate. Sulphuretted hydrogen occasions no change in solutions of nickel containing free mineral acid; but in alkaline solutions gives a black precipitate. Sulphide of ammonium in neutral solutions gives a black precipitate, soluble with difficulty in hydrochloric acid; but freely soluble in aqua regia.

_Estim._ Nickel may be thrown down from its ore in the form of either carbonate or hydrate, and after ignition may be weighed as oxide, each grain of which is equal to 7/8 gr. of pure nickel; or, more accurately, ·7871 gr.

According to Rose, nickel may be separated from cobalt as follows:——The mixed metals are dissolved in considerable excess of hydrochloric acids, and the solution is diluted with a very large quantity of water; a current of chlorine is then passed through the liquor for several hours, and the upper part of the flask is left filled with the gas after the current has ceased; barium carbonate is next added, in excess, the whole digested together, with frequent agitation for 15 or 18 hours, and then thrown on a filter. The filtrate yields pure nickelous oxide by precipitation with hydrate of potassium; whilst the residuum on the filter, after being washed in water, dissolved in hot hydrochloric acid, and the barium precipitated with sulphuric acid, furnishes, with hydrate of potassium, a precipitate of cobaltous hydrate, free from nickel, which, when washed and dried, is reduced in a platinum or porcelain crucible by hydrogen gas.

_Uses._ Nickel is chiefly employed in the manufacture of German silver. Some of its salts have been recently introduced into medical practice, and appear likely to prove most valuable additions to the materia medica. It has also been recently used for deposition by electrolysis on other metals, forming a hard, brilliant, non-tarnishing coating.

=Nickelic Oxide.= Ni_{2}O_{3}. _Syn._ SESQUIOXIDE OF NICKEL, PEROXIDE OF NICKEL. _Prep._ By passing chlorine through water holding the hydrate in suspension; or by mixing a salt of nickel with bleaching powder. An insoluble, black powder, which is decomposed by heat.

=Nick′elous Ace′tate.= Ni(C_{2}H_{3}O_{2})_{2}. _Syn._ NICKELII ACETAS, L. _Prep._ By neutralising acetic acid with nickelous carbonate, and gently concentrating by evaporation, so that crystals may form. Small green crystals, soluble in 6 parts of water.

=Nickelous Car′bonate.= NiCO_{3} _Syn._ NICKELII CARBONAS, L. _Prep._ This salt may be obtained in the manner described above in connection with the preparation of metallic nickel, or by simply adding carbonate of sodium to a solution of nickelous chloride of sulphate, but in this case some hydrate is precipitated along with it. The following is another formula which produces a nearly pure carbonate, but one which may still contain a little cobalt, the entire separation of which is a matter of extreme difficulty, and can best be effected in the manner recommended by Rose, described above:——

The mineral (crude speiss or kupfernickel) is broken into small fragments, mixed with from one fourth to one half its weight of iron filings, and the whole dissolved in aqua regia; the solution is gently evaporated to dryness, the residue treated with boiling water, and the insoluble ferrous arseniate removed by filtration; the liquid is next acidulated with hydrochloric acid, treated with sulphuretted hydrogen, in excess, to precipitate the copper, and, after filtration, is boiled with a little nitric acid, to bring back the iron into ferric salts; to the cold and largely diluted liquid a solution of bicarbonate of sodium is gradually added, and the ferric oxide separated by filtration; lastly, the filtered solution is boiled with carbonate of sodium in excess, and the pale green precipitate of carbonate collected, washed, and dried.

_Uses, &c._ It is freely soluble in the acids, and is chiefly employed to prepare the salts and other compounds of nickel.

=Nickelous Chlo′′ride.= NiCl_{2}. _Syn._ NICKELII CHLORIDUM, L. _Prep._ From nickelous carbonate and hydrochloric acid, as the acetate. Small green crystals, of the formula NiCl_{2},9Aq., which are rendered yellow and anhydrous by heat, unless they contain cobalt, when the salt retains a tint of green.

DOUBLE CHLORIDES. Nickelous chloride unites with the chlorides of ammonium, potassium, and sodium, to form pale green crystallisable salts, which have been used for depositing nickel in iron, lead, copper, &c.

=Nickelous Hy′drate.= Ni(HO)_{2}. By precipitating a soluble salt of nickel with caustic potassa. Hydrated. An ash-gray powder, freely soluble in acids, forming the ordinary salts of nickel.

=Nickelous Ox′alate.= NiC_{2}O_{4}. _Syn._ NICKELII OXALAS, L. _Prep._ By adding a strong solution of oxalic acid to a like solution of nickelous sulphate, and collecting the pale bluish-green precipitate which forms after a time. Used to prepare both metallic nickel and its oxide.

=Nickelous Oxide.= NiO. _Syn._ PROTOXIDE OF NICKEL. _Prep._ 1. By heating the nitrate, carbonate, or oxalate, to redness in open vessels. Anhydrous.

=Nickelous Sulphate.= NiSO_{4}. _Syn._ SULPHATE OF NICKEL. _Prep._ Dissolve nickelous carbonate or oxide in dilute sulphuric acid, evaporate down, and crystallise. Pale green prismatic crystals, and of the formula NiSO_{4},7Aq., or small pale green octahedrons, when crystallised at a higher temperature, containing NiSO_{4},6Aq.

=Nickelous and Potassium Sulphate.= NiSO_{4} K_{2}SO_{4},6Aq. _Syn._ DOUBLE SULPHATE OF NICKEL AND POTASSIUM. _Prep._ By crystallising a mixture of nickelous and potassium sulphates. Pale green crystals, readily soluble in water. Sodium and ammonium sulphates form similar compounds with nickelous sulphate.

=NICK′EL SIL′VER.= See GERMAN SILVER.

=NIC′OTINE.= C_{10}H_{14}N_{2}. _Syn._ NICOTINA, NICOTIA, L. A volatile base, discovered by Reiman and Posselt in tobacco.

_Prep._ (Ortigosa.) Infuse tobacco leaves for 24 hours in water acidulated with sulphuric acid, strain, evaporate to a syrup, add 1/6 of its volume of a strong solution of potassa, and distil in an oil bath at 288°, occasionally adding a little water to assist the process, and prevent the too great concentration of the solution of potassa in the retort; next saturate the distilled product with oxalic acid, evaporate to dryness, digest in boiling absolute alcohol, evaporate the resulting tincture to a syrup, and decompose the oxalate of nicotine thus obtained by adding potassa to it in a close vessel, and agitate the mass with ether, repeating the process with more ether until all the nicotine is dissolved out; lastly, distil the mixed ethereal solution in an oil bath. At first ether comes over, then water, and, lastly, nicotina, which, towards the end of the process, assumes a yellowish tint.

2. (Schloesing.) This chiefly differs from the preceding by directing the concluding distillation to be conducted in a retort, by the heat of an oil bath, at the temperature of 284° Fahr., in a current of hydrogen, for 12 hours; after which, by raising the heat to 356° Fahr., the nicotine distils over pure, drop by drop.

3. (Kirchmann). A tin vessel provided with two tubulures, is filled with tobacco, which is previously damped with sodium carbonate. One of the tubulures admits a glass tube reaching nearly to the bottom of the vessel; the other is provided with a glass tube merely penetrating the cork.

The vessel is made air-tight, placed into a boiling hot steam bath, and a rapid stream of carbonic acid gas passed through it, entering the vessel by the longer and leaving it by the shorter tube; the latter dips into a mixture of alcohol and dilute sulphuric acid.

In this manner a large yield of perfectly colourless nicotine is obtained. In order to obtain the pure alkaloid, caustic baryta is added to the solution, the latter evaporated to dryness, and the pure nicotine extracted with ether.

To estimate nicotine, weigh out 15 gr. of tobacco, digest for twenty-four hours with alcohol of 85 per cent. acidified with 15 drops of sulphuric acid, so as to make 150 cubic centimètres. Evaporate 50 cubic centimètres of the filtered liquid, and add iododydrargyrate of potassium to the residue. The number of cubic centimètres employed, multiplied by 0·00405 (0·001 of the equivalent of nicotine), gives the quantity of alkaloid contained in 5 grams of tobacco. (Linoffsky.)

_Prop., &c._ Nicotina is a colourless, volatile liquid; highly acrid and pungent; smelling strongly of tobacco; boiling at 375° Fahr. (482°——Pereira); soluble in water, ether, alcohol, and oils; and combining with the acids, forming salts, many of which are crystallisable. It is a frightful poison; 1/4 of a drop will kill a rabbit; a single drop will kill a large dog. Nicotina is the substance which was employed by the Count Bocarmé for the purpose of poisoning his brother-in-law, Gustave Fougnies, the particulars of which were developed in the celebrated trial, in Belgium, of that nobleman, in 1851. Good Virginia and Kentucky tobacco, dried at 212° Fahr., contain from 6% to 7% of nicotina; Havannah tobacco (_cigars_) less than 2%. (Schloesing.)

=NIGHT′MARE.= _Syn._ INCUBUS, EPHIALTES, L. The common causes of nightmare are indigestion and the use of narcotic and intoxicating substances. Its prevention consists in the selection of proper food, and in duly attending to the state of the stomach and bowels. Heavy and late suppers should be particularly avoided, as well as all articles of diet that are of difficult digestion, or apt to induce flatulency. When it arises from strong drink, tobacco, or opium, these should be abandoned, or employed in smaller quantities. A teaspoonful of aromatic spirits of ammonia, magnesia, or bicarbonate of soda, taken in a glass of cold water on going to bed, is a good and simple preventive. In cases accompanied by restlessness, a few drops of laudanum or tincture of henbane may be added. An occasional aperient is also excellent. See CHAMOMILE.

=NIGHT′SHADE (Deadly).= _Syn._ BELLADONNA (B. P., Ph. L. E. & D.). “The leaf, fresh and dried (leaves and root——Ph. D.), of _Atropa belladonna_, Linn.” “The fresh leaves and branches to which they are attached; also the leaves separate from the branches, carefully dried, of _Atropa belladonna_, gathered, when the fruit has begun to form, from wild or cultivated plants in Britain” (B. P.). “Oval, acute, very perfect, glabrous, when bruised, exhaling a disagreeable odour. The herb which grows spontaneously in hedges and uncultivated places is to be preferred to that which is cultivated in gardens.” (Ph. L.)

Belladonna is a powerful narcotic, and is used as an anodyne, antispasmodic, and discutient, in a variety of diseases,——neuralgia, arthritic pains, migratory rheumatic pains, spasmodic rigidity and strictures, angina pectoris, hooping-cough, fevers, phthisis, &c.; also as a prophylactic of scarlet fever, as a resolvent in enlarged and indurated glands, to produce dilatation of the pupil, &c., &c.——_Dose._ Of the powder, commencing with 1 gr., gradually and cautiously increased until dryness of the throat or dilation of the pupil occurs, or the head is affected. See ATROPIA.

=NIGHTSHADE (Woody).= _Syn._ BITTERSWEET; DULCAMARA (B. P., Ph. L. E. & D.), L. The “new shoots (caules) of _Solanum Dulcamara_, Linn.” “The dried young branches of the _Solanum Dulcamara_ (Bittersweet) from indigenous plants which have shed their leaves” (B. P.). “It is to be collected in autumn, after the leaves have fallen.” (Ph. L.) Diaphoretic, diuretic, and (in large doses) narcotic. See INFUSION OF DULCAMARA.

=NIO′BIUM.= See TANTALUM.

=NIP′PLES (Sore).= The most common form of this affection is that termed “chapped nipples” by nurses. As a preventive measure, the part may be moistened morning and evening, for some weeks before the period of lactation, with a little rum or brandy, which is more effective if slightly acidulated with a few drops of dilute sulphuric acid. Some persons employ tincture of tolu, or compound tincture of benzoin (Friar’s balsam) for this purpose.

When chaps, cracks, or like sores, arising from lactation, are once developed, one of the safest and most effective remedies is tincture of catechu, applied 3 or 4 times a day, by means of a camel-hair pencil.

The celebrated nostrum of Liebert for cracked nipples, “_Cosmétique infaillible et prompt contre les gerçures ou crevasses aux seins et autres_,” is a lotion formed of 10 gr. of nitrate of lead dissolved in 4 fl. oz. of rose water, and tinged with a little cochineal. The parts are moistened with the liquid, and are then covered with fine leaden nipple-shields, two of which are provided for the purpose. This is repeated soon after each time the child leaves the breast; and the nipple is carefully washed with a soft sponge and lukewarm water, and gently dabbed dry with a very soft towel, before the infant is again applied to it. This remedy is very successful, and has acquired great popularity and patronage in Brussels, Paris, Frankfort, and other parts. It must be recollected, however, that all applications of an active or poisonous nature should be employed with the greatest possible caution, as, unless unusual care is taken, a portion of the remedy may remain concealed within the delicate pores of the skin, and be sucked off by the infant, to the serious disturbance of its health.

=NITRAN′ILINE.= This substance is obtained by acting on nitrobenzol with a mixture of fuming nitric acid and oil of vitriol; Dinitro-benzol is formed, which is dissolved in alcohol, and the resulting solution subjected to the reducing action of ammonia and sulphuretted hydrogen, as described under aniline. Nitraniline forms yellow, acicular crystals, little soluble in cold water, but freely soluble in alcohol and ether. Its salts are crystallisable.

=NI′TRATE.= _Syn._ NITRAS, L. A salt of nitric acid (_e.g._ AgNO_{3}, nitrate of silver). The nitrates are very easily prepared by the direct solution of the metal, or its oxide, or carbonate, in nitric acid, which, in most cases, should be previously diluted with water. By evaporation, with the usual precautions, they may be obtained either in the pulverulent or crystalline form.

The nitrates are characterised by deflagrating when thrown on red-hot charcoal; also by their aqueous solutions, after being mixed with half their bulk of strong sulphuric acid and thoroughly cooled, yielding a brown cloud with a crystal or concentrated solution of ferrous sulphate. See NITRIC ACID, and the respective metals.

=NI′TRE.= Nitrate of Potassa. See POTASSIUM.

=NI′TRIC ACID. HNO_{3}.= _Syn._ AZOTIC ACID; ACIDUM NITRICUM (B. P., Ph. L., E., & D.); AQUAFORTIS.

_Prep._ 1. (Ph. E. and Ph. L. 1836.) Purified nitre (dried) and sulphuric acid, equal parts; mix in a glass retort, and distil with a moderate heat, from a sand bath (or naked gas flame——Ph. E.) into a cool receiver, as long as the fused materials continue to evolve vapours. “The pale yellow acid thus obtained may be rendered nearly colourless (if desired) by gently heating it in a retort.” (Ph. E.) Sp. gr. 1·500. In the present Ph. L. this acid is included in the materia medica. (See _below_.)

2. (Ph. D.) The nitrate of potassa is dissolved in water, the solution treated with a little nitrate of silver, filtered, evaporated to dryness, weighed, and then treated as above.

3. Nitrate of soda (cubic nitre, Chili saltpetre) is introduced, in quantities varying between 4 and 10 lbs., into a cylindrical iron retort, which it will only half fill, and after the lid is luted on and the connection made with the condensers, an equivalent of oil of vitriol is poured in through an aperture provided for the purpose, and the charge is worked off with a gradually increased heat. The condensing apparatus consists of a series of 5 or 6 salt-glazed stoneware receivers, about 1/6th part filled with cold water. The product of this process is the strongest brown and fuming ‘NITROUS ACID’ of commerce (AQUAFORTIS, FUMING NITRIC ACID; ACIDUM NITROSUM; ACIDUM NITRICUM FUMANS), and has usually the sp. gr. 1·45. It is rendered colourless by gently heating it in a glass retort, when it forms COMMERCIAL NITRIC ACID (sp. gr. 1·37 to 1·4.)

4. (PURE MONOHYDRATED NITRIC ACID.) By mixing the strongest commercial acid with about an equal quantity of oil of vitriol; redistilling; collecting apart the first portion which comes over, and exposing it, in a vessel slightly warmed and sheltered from the light, to a current of dry air made to bubble through it until the nitrous acid is completely removed.

_Prop._ Pure liquid nitric acid is colourless, highly corrosive, and possesses powerful acid and oxygenising properties. The sp. gr. of the strongest liquid acid (monohydrated nitric acid) has the sp. gr. 1·517 at 60° Fahr. “On boiling nitric acid of different degrees of concentration at the ordinary atmospheric pressure, a residue is left boiling at 249° Fahr., and 29 in. barometer, having a sp. gr. 1·414 at 60° Fahr.” (Fownes.) Acid of less density than 1·414 parts with water, and gradually becomes stronger by boiling; but acid of less sp. gr. than 1·414 is weakened by exposure to heat. When exposed to intense cold, liquid nitric acid freezes. It is rapidly decomposed, with loss of oxygen, by contact with most organic and many metallic and non-metallic bodies. In many cases these reactions occur with considerable violence, and the production of light and heat.

_Pur._ The nitric acid of commerce is generally contaminated by hydrochloric acid, nitrous acid, sulphuric acid, or chlorine, or by their soda or potassa salts, and, occasionally, iodine, together with an excess of water. The last is readily detected by the sp. gr., and the others by the appropriate tests. “Colourless. Contains 70% of HNO_{3}. Sp. gr. 1·42. 90 gr. by weight, mixed with 1/2 oz. of distilled water, require for neutralisation 1000 grain measures of the volumetric solution of soda. Evaporated, it leaves no residue. Diluted with six volumes of distilled water, it gives no precipitate with chloride of barium or nitrate of silver——indicating absence of sulphuric and hydrochloric acids.” (B. P.) 5 measures of acid, sp. gr. 1·5, mixed with 2 of water, condensed into 6-1/2 measures, and makes the sp. gr. 1·42. “Free from colour. Sp. gr. 1·42. Exposed to the air, it emits very acrid vapours. Totally volatilised by heat. Diluted with 3 times its volume of water, it gives no precipitate with either nitrate of silver or chloride of barium. 100 gr. of this acid (sp. gr. 1·42) are saturated by 161 gr. of crystallised carbonate of soda.” (Ph. L.) The Ph. E. states the density of commercial nitric acid is 1·380 to 1·390. “If diluted with distilled water it precipitates but slightly, or not at all, with solution of nitrate of baryta or nitrate of silver.” The best ‘double aquafortis’ of the shops (aquafortis duplex) has usually the sp. gr. 1·36; and the single aquafortis (aquafortis simplex), the sp. gr. 1·22; but both are commonly sold at much lower strengths.

_Tests._——1. It stains the skin yellow.——2. When mixed with a little hydrochloric acid or chloride of ammonium, it acquires the power of dissolving gold leaf.——3. Morphia, brucia, and strychnia, give it a red colour, which is heightened by ammonia in excess.——4. When placed in a tube, and a solution of protosulphate of iron is cautiously added, a dark colour is developed at the line of junction, which is distinctly visible when only 1/24,000th part of nitric acid is present. This test may be often conveniently modified by dropping into the liquid a crystal of protosulphate of iron; the fluid immediately surrounding this crystal then acquires a dark brown colour, which disappears upon simple agitation of the fluid, or by heating it.——5. When mixed with a weak solution of sulphate of indigo, and heated, the colour of the latter is destroyed.——6. When saturated with carbonate of potassium or sodium, and evaporated to dryness, the residuum deflagrates when thrown on burning coals.——7. When the mixture of a nitrate with cyanide of potassium, in powder, is heated on a piece of platinum, a vivid deflagration follows, attended with distinct ignition and detonation. (Fresenius.) It is stated that sulphate of aniline is an extremely delicate test for nitric acid. The following is the method of its application:——About a cubic centimètre of pure concentrated sulphuric acid (sp. gr. 1·84) is placed in a watch-glass; half a cubic centimètre of a solution of sulphate of aniline (formed by adding ten drops of commercial aniline to 50 c.c. of diluted sulphuric acid in the proportion of 1 to 6) is poured on, drop by drop; a glass tube is moistened with the liquid to be tested, and moved circularly in the watch-glass. By blowing on the mixture during the circular agitation, when a trace of nitric acid is present, circular striæ are developed of a very intense red colour, tinting the liquid rose. With more than a trace of nitric acid the colour becomes carmine, passing to a brownish red. This process serves to detect the presence of nitric acid in the sulphuric acid of commerce. It will also reveal the presence of nitrates in water.[46]——8. Take a quantity of diphenylamine, about the size of a mustard seed, put it into a test-tube, and pour a little sulphuric acid over it, then add a drop or two of water, so as to increase the temperature sufficiently to effect the solution of the diphenylamine, and the test is ready for use. Now add very gently the solution to be tested, and if only a trace of nitric or nitrous acid be present, a beautiful and very permanent blue colouration is produced at the junction of the two liquids, but if there be any quantity of the nitrogen compound, the colour becomes almost black. This reaction is so delicate and certain that, in the case of a solution of nitric acid containing about 1 part B. P. acid in 10,000 of water, the reaction is most distinct; one part of nitrite of potassium in 30,000 of water gives also almost unmistakable evidence of the presence of the nitrogen acid.

[Footnote 46: ‘Pharmaceutical Year Book.’]

The following process for the quantitative estimation of nitric acid is by Fischer:[47]——Indigotin prepared by reduction of indigo by means of grape sugar, alcohol, and caustic soda, oxidation in the air, and solution in sulphuric acid, may be kept unchanged for years. Five c.c. of such a solution, diluted with water and mixed with 30 c.c. of pure sulphuric acid, is titrated by adding a standard nitric acid solution until the blue colour gives place to a light green; the indigo solution is then diluted, so that 1 c.c. shall be equal to 0·0025 milligramme equivalents of nitric acid, or 0·2525 milligramme of potassium nitrate. If a water is being examined it is run into 4 c.c. of the titrated indigo solution, mixed with 20 c.c. of sulphuric acid, until the blue colour changes to light green. Ten, divided by the number of c.c. of water used, expresses the milligramme equivalents of nitric acid per litre; thus, if 4 c.c. of water are used, there are 2·5 milligramme equivalents of nitric acid, equal to 252·5 milligrammes of potassium nitrate per litre. If a preliminary test with brucine has shown that the water contains very little nitric acid, 2 c.c. only of the indigo solution must be used, or sometimes as little as 1 c.c. If more than 8 c.c. of water is required to destroy the blue colour, 100 c.c. must be evaporated down to the volume of 8 c.c. and then titrated. The volume of sulphuric acid must be at least double the sum of the volumes of indigo and water; the temperature must not sink under 110°.

[Footnote 47: Dingl., ‘Polyt. Journ.’ ccxiii, 423-427; ‘Journ. Chem. Soc.,’ 2nd series, xiii, 481.]

The nitrates may all be tested as above by first adding a small quantity of pure sulphuric acid, which will liberate the nitric acid of the salt.

_Estim._——The strength of nitric acid may be roughly estimated by its sp. gr.; but more accurately by ascertaining the amount of carbonate of sodium, or other salt of known composition, which is required to neutralise it. To render this assay trustworthy, it must be, in all cases, also tested to detect the presence of impurities. See ACIDIMETRY.

_Ant., &c._ See ACIDS.

_Uses._ Nitric acid is employed in assaying, in dyeing, in etching on copper, in the preparation of gun-cotton, oxalic and sulphuric acids, &c. In medicine it is used as a caustic to corns and warts; and in doses of 1 to 10 drops, in a tumbler of water, in liver complaints, fevers, dyspepsia, syphilis, to remove the effects of mercury, or as a substitute for that drug, &c. Externally, it is employed in the form of baths, lotions, and ointment. Dr Collier states that a strong lotion of nitric acid is almost a specific in lepra, and several other kindred skin diseases.

_Concluding Remarks._——The common source of nitric acid is nitrate of potassium, but it may also be obtained from other nitrates by a similar process. Nitrate of sodium is frequently used instead of nitrate of potassium, and is more convenient in some respects, as the residuum is more easily dissolved out of the retort or cylinder. The residuum of the common process with nitre (‘sal enixum’) is chiefly employed as a flux by the glass-houses, and as a source of potash in the manufacture of alum.

By proper management nitre yields more than 2/3 of its weight of pure nitric acid, sp. gr. 1·500; and nitrate of soda, its own weight of acid, sp. gr. 1·4.

By the patent process of M. Mallet, dried nitrate of soda is decomposed by dried or monohydrated boracic acid, by heating the two together. The products are liquid nitric acid, which distils over, and biborate of soda (borax), which remains in the retort.

The crude coloured nitric acid of commerce (aquafortis) was originally prepared by distilling a mixture of nitre and copperas, and is still sometimes obtained in this way.

The nitric acid of commerce may be freed from the impurities alluded to above by one or other of the following methods:——

1. By the addition of a little nitrate of silver, as long as it produces any cloudiness, and, after repose, decanting the clear acid, and rectifying it at a heat under 212°. To ensure a perfectly colourless product, a small portion of pure black oxide of manganese should be put into the retort. (Murray.)

2. By agitating the acid with a little red oxide of lead, and then rectifying it, as before.

3. By adding 1% of bichromate of potassa to the acid before rectifying it. This answers well for acid not stronger than sp. gr. 1·48.

4. By rectification at a gentle heat, rejecting the first portion that comes over, receiving the middle portion as genuine acid, and leaving a residuum in the retort. (Ure.)

According to Apjohn and others, the strongest liquid nitric acid, sp. gr. 1·520, is a monohydrate; that of the sp. gr. 1·500, a sesquihydrate; that of 1·486, a binhydrate; and that of 1·244, a quadrihydrate; or containing respectively 1, 1-1/2, 2, and 4 atoms of water. (See _below_.)

=Nitric Acid, Anhy′drous.= N_{2}O_{5}. _Syn._ NITRIC ANHYDRIDE. This interesting substance was first obtained in a separate form by M. Deville, in 1849.

_Prep._ (M. Deville.) Nitrate of silver is dried by exposure to a current of dry carbonic acid at a temperature of 356° Fahr., and the tube containing it is then immersed in a water bath heated to 203° Fahr.; pure dry chlorine gas is next passed through the apparatus, and, as soon as the reaction commences, the temperature is retraced to 154° or even 136°, but not lower; the production of crystals in the receiver, which must be cooled by a powerful freezing mixture, soon commences; lastly, the liquid portion of the product is removed by a current of dry carbonic-acid gas.

_Prop., &c._ Colourless prismatic crystals, which melt at 86° Fahr., boil at about 115°, and at 122° begin to suffer decomposition; added to water, much heat is generated; it rapidly attacks organic bodies, even caoutchouc; sometimes it explodes spontaneously. The process for its preparation is tedious and difficult.

=Nitric Acid, Dilute.= ACIDUM NITRICUM DILUTUM (B. P., Ph. L., E., & D.), L. _Prep._ 1. (Ph. L.) Nitric acid (sp. gr. 1·42), 3 fl. oz.; distilled water, 17 fl. oz.; mix. Sp. gr. 1·082. “1 fl. oz. is saturated by 154 gr. of the crystals of carbonate of soda.” It contains about 12% of pure anhydrous acid.

2. (Ph. E.) Nitric acid (1·500), 1 fl. oz.; distilled water, 9 fl. oz. Or, commercial nitric acid (1·390), 1 fl. oz. 5-1/2 dr.; water, 9-1/2 fl. oz. Sp. gr. 1·077. It contains 11·16% of pure dry nitric acid.

3. (Ph. D.) Nitric acid (1·500), 4 fl. oz.; water, 29 fl. oz. Contains about 9·7% of pure acid. The above are used for convenience in dispensing.——_Dose_, 15 drops to 1/2 fl. dr., or more. The above must not be confounded with the acidum nitricum dilutum, Ph. D. 1826, which had the sp. gr. 1·280, nor with the following:——

4. (Henry’s.) Sp. gr. 1·143; equal in saturating power to hydrochloric acid sp. gr. 1·074, and sulphuric acid 1·135. Used in assaying.

5. (B. P.) Nitric acid, 6; distilled water sufficient to make the mixture when cooled to 60° Fahr., measure 31. Contains 15 per cent. of anhydrous nitric acid. _Test._ Sp. gr. 1·101. Six fluid drachms (361·3 grains) by weight require for neutralisation 1000 grain measures of the volumetric solution of soda, and, therefore, contain exactly one equivalent in grains of anhydrous acid, namely, 54 gr.——_Use._ Tonic, astringent, lithonlytic.——_Dose_, 10 to 30 minims.

=Nitric Acid, Fuming.= _Syn._ NITROUS ACID‡; ACIDUM NITRICUM FUMANS, L. The red fuming nitrous or nitric acid of commerce is simply nitric acid loaded with nitric peroxide (which _see_). That of the Ph. Bor. is distilled from nitre, 2 parts; oil of vitriol, 1 part.

=NI′TRIC ANHY′DRIDE.= See NITRIC ACID, ANHYDROUS.

=NI′TRIC OXIDE.= See NITROGEN, OXIDES OF.

=NI′TRITE.= A salt of nitrous acid; _e.g._ KNO_{2}, nitrite of potassium.

=NITRO-BEN′ZOL.= C_{2}H_{5}NO_{2}. _Prep._ By treating benzol with strong fuming nitric acid, with heat; after the violence of the reaction is over, the liquid is diluted with water, and the heavy oily fluid which separates is collected, washed, and dried.

_Prop., &c._ Yellowish, very sweet; smells of bitter almonds; insoluble in water; little affected by reagents; boils at 415° Fahr.; sp. gr. 1·209. Heated with an alcoholic solution of caustic potassa, and the mixture submitted to distillation, it yields a red, oily liquid, from which large red crystals of azobenzol separate. These are nearly insoluble in water, freely soluble in alcohol and ether, melt at 149° Fahr., and boil at 559·4° Fahr. BINITROBENZOL is made by dissolving benzol in a mixture of equal volumes of the strongest nitric and sulphuric acids, and boiling the liquid for a few minutes; the crystals (dinitrobenzol) which form as it cools are insoluble in water, but are freely soluble in alcohol. Nitro-benzol is extensively used as a substitute for the essential oil of bitter almonds, in perfumery. It is very poisonous, a quality, which Letheby asserts, it acquires owing to its conversion in the animal economy into aniline. M. Ferrand states that the presence of nitro-benzol in essence of bitter almonds may be detected as follows:——Heat to ebullition, in a test tube, three or four c.c. of a 20 per cent. alcoholic solution of potash, together with ten drops of the suspected essence. If nitro-benzol be present, the mixture takes a red colour; if the essence of bitter almonds be pure, it becomes a pale straw colour.

=NI′TROGEN.= N. _Syn._ AZOTE; NITROGENIUM, AZOTUM, L. A gaseous elementary substance, discovered by Rutherford, in 1722, and found to be a constituent of the atmosphere by Lavoisier, 1755. It is found both in the organic and inorganic kingdoms of nature; it forms about 4/5, or 78% of the bulk of the atmosphere, enters largely into the composition of most animal substances, and is a constituent of gluten, the alkaloids, and other vegetable principles.

_Prep._ 1. A small piece of phosphorus is placed in a capsule floating on the surface of the water of the pneumatic trough, and after setting it on fire a gas or bell-jar is inverted over it; as soon as the combustion is over, and the fumes of phosphoric anhydride have subsided, the residual gas is washed by agitation with recently boiled distilled water, or with a solution of pure potassa. It may be dried by either letting it stand over fused chloride of calcium, or, what is better, by passing it through concentrated oil of vitriol.

2. A porcelain tube is filled with copper turnings, or, preferably, with spongy copper (obtained by reducing the oxide with hydrogen), and is then heated to redness, a stream of dry atmospheric air being at the same time directed through it. By repeating the process with the same air, and finally passing it over fragments of pumice moistened with strong solution of potassa to absorb carbonic anhydride, the product is rendered quite pure.

3. Chlorine gas is passed into a solution of pure ammonia, care being taken to employ a considerable excess of the latter; the evolved gas, after being dried, is pure nitrogen. There is some danger of producing the explosive compound, chloride of nitrogen, with this process.

4. (Corenwinder.) From solution of nitrate of potassium, 1 volume; concentrated solution of chloride of ammonium, 3 vols.; gently heated together in a flask, and the evolved gas passed through sulphuric acid. Pure.

5. By boiling a solution of nitrite of ammonium, or, which amounts to the same thing, a mixture of one measure of a solution of nitrite of potassium and three measures of a solution of chloride of ammonium. Both solutions must be concentrated. This is the easiest method of preparing nitrogen and of obtaining the gas in a pure state.

_Note._——The nitrite of potassium to be employed in this process is best prepared by passing nitrous anhydride, evolved from starch and nitric acid, into a solution of potassa (sp. gr. 1·38) till it imparts an acid reaction to test-paper, and then neutralising by the addition of potassa.

6. From lean flesh digested in nitric acid, at a gentle heat.

_Prop., &c._ Pure nitrogen is a colourless, odourless, tasteless gas, neither combustible nor capable of supporting combustion or respiration. It is neutral to test-paper, does not affect lime water, and is only slightly absorbed by pure water. Its sp. gr. is ·9713. It is recognised by its purely negative qualities.

=Nitrogen, Chlo′′ride of.= NCl_{3}. _Syn._ NITROGEN TRICHLORIDE, TERCHLORIDE OF NITROGEN. This compound was discovered by Dulong in 1811, but its nature was first accurately determined by Sir H. Davy.

_Prep._ (Liebig.) Dissolve chloride of ammonium, 1 oz., in hot water, 12 or 14 oz., and as soon as the temperature has fallen to 90° Fahr., invert a wide-mouthed glass bottle full of chlorine over it. The gas is gradually absorbed, the solution acquires a yellowish colour, and in the course of 15 to 20 minutes yellow, oil-like globules of chloride of nitrogen form upon the surface of the liquid, and ultimately sink to the bottom. The globules, as they descend, should be received in a small leaden saucer, placed under the mouth of the bottle for the purpose.

_Prop., &c._ Chloride of nitrogen should consequently be only prepared in very small quantities at a time. Both its discoverer and Sir H. Davy met with severe injuries while experimenting on it. Its sp. gr. is 1·653; it volatilises at 160° Fahr., and between 200° and 212° fulminates violently. Contact with combustible bodies at ordinary temperatures immediately causes detonation. _The explosive power of this compound seems to exceed that of every known substance, not even excepting fulminating silver:_ A minute globule, no larger than a grain of mustard seed, placed on a platina spoon, and touched with a piece of phosphorus stuck on the point of a penknife, immediately explodes, and shivers the blade into fragments, at the same time that the vessel that contains it is broken to pieces. Olive oil, naphtha, and oil of turpentine, have a similar effect. See NITROGEN, IODIDE OF (_below_).

=Nitrogen, I′odide of.= NI_{2}. _Syn._ NITROGEN TRI-IODIDE, TERIODIDE OF NITROGEN. A dark brown or black insoluble powder, which is most safely and conveniently prepared by saturating alcohol (sp. gr. ·852) with iodine, adding a large quantity of the strongest pure solution of ammonia, and agitating the mixture; water must now be added, when iodide of nitrogen will be precipitated, and must be carefully washed with cold distilled water. The filter containing the precipitate should be spread out on a sheet of glass and torn into small pieces while the iodide is still moist. The precipitate should be simply exposed to air only.

_Prop., &c._ It detonates violently as soon as it becomes dry, by the slightest pressure or friction, even that of a feather, and often spontaneously; but this explosion is scarcely so powerful as that of the chloride of nitrogen. It also explodes whilst moist, though less readily. It should only be prepared in very small quantities at a time. Recent researches induce the belief that both the above compounds contain hydrogen.

=Nitrogen, Ox′ides of.= Nitrogen forms 5 distinct compounds with oxygen.

1. =Nitrous ox′ide.= _Syn._ PROTOXIDE OF NITROGEN; LAUGING GAS; NITROGENII PROTOXYDUM, L. _Prep._ From fused nitrate of ammonium, introduced into a glass retort, or a flask furnished with a bent tube, and then exposed, over a spirit-lamp, or charcoal-chauffer, to a temperature of about 389° Fahr.; the evolved gas may be collected in bladders, gas-bags, a gasometer, or in the pneumatic trough over warm water. The gas may be purified by pouring it through three wash-bottles, one containing water, one a solution of sulphate of iron, and the other a solution of potassa.

_Prop., &c._ Colourless; possesses an agreeable odour, and a sweetish taste; at 32°, under a pressure of 30 atmospheres, it is liquid; this, when exposed under the receiver of a powerful air-pump, changes into a snow-like solid; at -180° Fahr., it is a transparent, colourless, crystalline body; it supports combustion, and is absorbed by cold water. Sp. gr. 1·520. Its most remarkable property is its action on the system when inspired. A few deep inspirations are usually succeeded by a pleasing state of excitement, and a strong propensity to laughter and muscular exertion, which soon subside, without being followed by languor or depression. Its effects, however, vary with different constitutions. From 4 to 12 quarts may be breathed with safety. It produces temporary insensibility to pain, like chloroform or ether; but its use is dangerous when affections of the heart, lungs, or brain are present. This gas is now successfully and extensively employed as an anæsthetic in dental surgery.

_Obs._ No particular caution is required in preparing the above compound, except the use of too much heat. The temperature should be so arranged as to keep the melted mass in a state of gentle ebullition, and should not be allowed, under any circumstances, to exceed about 500° Fahr. Should white fumes appear within the retort after the evolution of the gas has commenced, the heat should be at once lowered, as, when heated to about 600°, nitrate of ammonia explodes with violence.

Nitrous oxide may also be made in the same way, from crystallised nitrate of ammonia, or by exposing nitric oxide for some days over iron filings moistened with water, but, without great care, the product is not always fit for respiration. When pure, it is colourless, has an agreeable odour, and does not affect solution of nitrate of silver. See ANÆSTHETICS.

2. =Nitric oxide.= NO. _Syn._ DEUTOXIDE OF NITROGEN, NITROUS GAS, BINOXIDE OF NITROGEN; NITROGENEE BINOXYDUM, L. _Prep._ By pouring nitric acid, sp. gr. 1·2, on metallic copper, in the form of turnings, clippings, or wire. Effervescence ensues, and nitric oxide is evolved, and may be collected over water or mercury in the pneumatic trough. The residual liquid yields crystals of nitrate of copper on evaporation.

_Prop., &c._ A colourless, tasteless, inodorous, irrespirable, and incombustible gas. In contact with free oxygen, it produces dense orange or red vapours of nitric peroxide (NO_{2}), which are freely absorbed by water. Nitric oxide is absorbed by a solution of ferrous sulphate, which it turns of a deep brown or nearly black colour, which is removed by boiling. Sp. gr. 1·039.

=Nitrous Anhydride.= N_{2}O_{3}. _Syn._ NITROGEN TRIOXIDE, ANHYDROUS NITROUS ACID. The easiest method of obtaining this compound consists in heating 1 part of powdered starch with 8 parts of nitric acid of sp. gr. 1·25, and passing the evolved gases, first through a drying tube two feet long containing fused chloride of calcium, and then into a dry and empty U-tube cooled to 20° Fahr. by surrounding it with a mixture of pounded ice and crystallised chloride of calcium. Nitrous anhydride thus produced is a blue liquid which emits red fumes, and which on admixture with water at ordinary temperatures is decomposed, producing nitric acid and nitric oxide. If nitrous anhydride be mixed with water at temperatures below 0° Fahr. the two combine, and a blue solution is formed which (probably) contains nitrous acid (HNO_{2}). See NITROUS ACID.

=Nitrogen Pentoxide.= N_{2}O_{5}. _Syn._ NITRIC PENTOXIDE, NITRIC ANHYDRIDE, ANHYDROUS NITRIC ACID. See NITRIC ACID (ANHYDROUS).

=Nitrogen Peroxide.= NO_{2}. _Syn._ NITRIC PEROXIDE, PEROXIDE OF NITROGEN, NITROGEN TETROXIDE, HYPONITRIC ANHYDRIDE. This compound forms the chief constituent of the red fumes which develop on mixing nitric oxide with air or oxygen. It is most readily prepared by heating thoroughly dried nitrate of lead in a retort, and conducting the evolved gases into a U-tube surrounded with a freezing mixture of ice and salt for the purpose of condensing the nitric peroxide. If the U-tube be perfectly dry, and the cold intense, the nitric peroxide obtained assumes the form of transparent crystals, but the presence of the slightest trace of moisture prevents their formation and produces instead a colourless liquid which, as the temperature rises, acquires a yellow and ultimately a red colour. Nitric peroxide dissolves in nitric acid and turns it of a yellow or red hue. The so-called ‘_nitrous acid_’ or ‘_fuming nitric acid_’ of commerce owes its deep red colour to the presence of this compound. At very low temperatures water converts nitric peroxide into nitric and nitrous acids; at ordinary temperatures it transforms it into nitric acid, nitrous acid, and nitric oxide.

=NITRO-GLYCERIN.= _Syn._ GLONOIN, NITRATE OF GLYCERYL, TRINITRITE, NITROLEUM, FULMINATING OIL, TRI-NITROGLYCERIN. This dangerously explosive compound, from the use of which in mining, quarrying, and such like operations so many fatal accidents have occurred, is glycerin in which 3 atoms of hydrogen have been replaced by 3 molecules of nitroxyl (NO_{2}), as illustrated by the following formulæ:

Glycerin. Nitro-glycerin. C_{3}H_{5} } (H } ) = C_{3}H_{5} } (H } ) }O_{3} + 3 ( }O ) } O_{3} + 3 ( } O) H_{3} } (NO_{2} } ) (NO_{2})_{3} } (H } )

It was discovered in 1847 by Dr. Sobrero, a pupil of Pelouze.

Kopp prepares nitro glycerin by mixing 3 parts of sulphuric acid, of sp. gr. of 1·767, with 1 part of fuming nitric acid. 2800 grammes of the mixed acids are added to 350 grammes of glycerin, great care being necessary to avoid any elevation of temperature, which would lead to a violent reaction, resulting in the conversion of the glycerin into oxalic acid.

After standing 5 or 10 minutes, the mixture is poured into four or six times its bulk of very cold water to which a rotatory motion has been imparted. The nitro-glycerin falls to the bottom of the vessel as an oily-looking liquid, which is washed by decantation. The manufacture of nitro-glycerin is attended with considerable danger, since very slight friction or pressure is sufficient to determine its explosion. Hence many methods have been suggested for guarding against accidents from it during storage. One of these consists in mixing it with finely powdered glass.

Wurtz advises the nitro-glycerin to be mixed with solutions of nitrate of lime, zinc, or magnesia, the solutions to have a sp. gr. equal to the nitro-glycerin. By this means a harmless emulsion would be formed, and the nitro-glycerin would be recoverable when required for use by simply adding water. Nobel’s plan consists in dissolving it in wood spirit.

_Prop._ Nitro-glycerin is a fluid of a yellow or brownish colour, having a sp. gr. of 1·6. It dissolves in alcohol, ether, and wood naphtha, from all of which it may be recovered by the addition of water. Dissolved in either of these solutions it becomes converted into a crystalline mass when exposed to a low temperature. If subjected to a blow it explodes with fearful violence, a single drop placed upon paper, and struck upon an anvil, giving rise to a report that is almost deafening. Neither a spark nor the application of a lighted body is said to cause its ignition, which takes place with difficulty even if it be applied to a thin layer of the substance. 100 parts of nitro-glycerin yield on combustion:

Water 20 parts. Carbonic acid 58 ” Oxygen 3·5 ” Nitrogen 18·5 ” —————— 100·0[48]

[Footnote 48: Wagner.]

As the specific gravity of nitro-glycerin is 1·6, one part by bulk will yield by combustion:——

Aqueous vapour 554 volumes. Carbonic acid 469 ” Oxygen 39 ” Nitrogen 236 ” —————— 1298[48] ”

Other experimenters affirm that, instead of free oxygen, nitrous oxide is one of the products of the combustion of nitro-glycerin. According to Nobel the heat liberated when nitro-glycerin is exploded, causes the expansion of the gases to be eight times their original bulk; therefore, one volume of the substance will yield 10,384 volumes of gas, whilst one part by bulk of gunpowder only yields 800 volumes of gas. If these data be correct the explosive force of nitro-glycerin is thirteen times greater than that of powder, bulk for bulk, and eight times greater weight for weight.

Böttger has devised a process for the preparation of nitro-glycerin, which being, as he affirms, entirely free from danger, adapts it for lecture experiments:——A few grains of pure glycerin, free from water, is poured into a test-tube, which is surrounded by a freezing mixture, and containing a mixture of one volume of the most concentrated nitric acid (1·52 sp. gr.), and two volumes of the strongest sulphuric acid (1·83 sp. gr.). Then, as quickly as possible, the whole is poured into a larger quantity of cold water. The nitro-glycerin, which has formed like oil drops, sinks rapidly to the bottom, being specifically the heavier liquid. It is then washed several times by decantation with fresh water, and, lastly, with a weak solution of soda.

Remove the water with a few pieces of fused chloride of calcium. Then the nitro-glycerin is in such purity that it may, without danger, be kept any length of time for lecture experiments.

=NITRO-HYDROCHLO′RIC ACID.= _Syn._ NITRO-MURIATIC ACID; AQUA REGIA, ACIDUM NITRO-HYDROCHLORICUM (B. P.), A NITRO-MURIATICUM, L.; EAU RÉGALE, Fr. _Prep._ 1. (B. P.) Nitric acid, 3; hydrochloric acid, 4; water, 25. Mix the acids twenty-four hours before adding the water. (This precaution is necessary to allow of the development of the chlorine, and the chloronitrous and chloronitric gases which result from the mutual decomposition of the two acids, and upon which the therapeutic activity of the agent depends). Colourless. Keep the mixture in a cool and dark place.

2. (Ph. D. 1826). Nitric acid, 1 part; hydrochloric acid, 2 parts (both by measure); mix in a refrigerated bottle, and keep the mixture in a cold and dark place. Used to dissolve gold and platinum; and in medicine, in liver complaints, syphilis, the exanthemata, &c., either externally, in doses of 5 to 15 drops in water, or externally, as a foot- or knee-bath. It is also occasionally employed as a caustic.

3. (AQUA REGIA WITH SAL AMMONIAC.) Nitric acid (sp. gr. 1·2), 16 fl. oz.; sal ammoniac, 4 oz.; dissolve. Occasionally used by dyers; does not keep well.

4. (DYERS’ AQUAFORTIS.) Colourless nitric acid (sp. gr. 1·17), 10 lbs.; hydrochloric acid (sp. gr. 1·19), 1 lb.; mix. Used by dyers.

=NITRO-PRUS′SIDES.= A series of salts discovered by Dr Playfair, and obtained by the action of nitric acid on the ferrocyanides and ferridcyanides. The most important of these salts is the nitroprusside of sodium (NA_{2} (NO) FeCy_{5}. 2Aq.). _Prep._ Dissolve 2 parts of powdered ferrocyanide of sodium in 5 parts of common nitric acid, previously diluted with its own volume of water. When the evolution of gas has ceased, digest the solution on a water bath until it no longer yields a blue but slate-coloured precipitate with ferrous sulphate. Cool the liquid, filter, neutralise the filtrate with carbonate of sodium, and again filter. This filtrate, on evaporation, yields crystals consisting of a mixture of nitro-prusside of sodium and nitrate of potassium; the former, which may be recognised by their rhombic shape and their fine ruling colour, should be picked out and preserved.——_Use._ As a test for soluble sulphides, with which nitro-prusside of sodium strikes a beautiful violet tint. According to Playfair this is the most delicate test for alkaline sulphides.

=NI′TROUS ACID.= HNO_{2} See NITROUS ANHYDRIDE, under NITROGEN, OXIDES OF.

=NITROUS OXIDE.= See NITROGEN, OXIDES OF.

=NODE.= _Syn._ NODUS, L. A hard tumour proceeding from a bone, and caused by the swelling of its external membrane. The bones of the leg, forehead, and forearm, are those most commonly attacked. Nodes are generally accompanied with considerable pain, and often with caries and loss of vitality.

=NOLI ME TANGERE.= See LUPUS.

=NOMENCLATURE (Chemical).= The following information will doubtless prove useful to many of our readers, as serving to explain terms which are necessarily of frequent occurrence in this work:

ACIDS.——_a._ When a substance produces only one acid compound, the name of this acid is formed by adding the termination -IC to that of the radical, or to the leading or characteristic portion of it; as sulphuric acid, an acid of sulphur. This is Latinised by changing -IC into -ICUM; as, _acidum, sulphur_ICUM.——_b._ When a body forms two acid compounds containing oxygen, the name of the one containing the smaller proportion of that substance ends in -OUS; as _nitr_OUS acid, which contains 1 atom of nitrogen and 2 of oxygen; _nitr_IC acid, containing 1 atom of nitrogen and 3 of oxygen. In this case the Latin name ends in -OSUM; as, _acidum nitr_OSUM.——_c._ When a substance forms more than two acids with oxygen, the Greek preposition HYPO- (below or under) is prefixed to the name of the acid in -OUS or -IC next above it; as, HYPO_chlorous acid_.——_d._ When a new acid compound of a substance is discovered, containing more oxygen than another acid of the same substances already known, the name of which ends in -IC, the prefix PER- or HYPER- is added; as, PER_iodic acid_. This may be illustrated by the oxygen acids of chlorine:——

Hypochlorous acid (_acidum hypochlorosum_) HClO Chlorous ” ( ” _chlorosum_) HClO_{2} Chloric ” ( ” _chloricum_) HClO_{3} Perchloric or} Hyperchloric } ” ( ” _perchloricum_) HClO_{4}

=OXIDES.= The names of these have, in general, reference to the number of atoms of oxygen which they contain. When a metal forms only one basic compound with oxygen, this compound is simply called the oxide of such base; but as most substances form more than one compound with oxygen, certain prefixes are introduced to express the proportions. In such cases it is generally found that one out of the number has a strongly marked basic character, and contains 1 atom of each of its constituents. This is called the oxide, protoxide, or monoxide, and forms the standard to which those both above and below it are preferred. Thus, supposing M to be the metal, we may have:——

Suboxide or dioxide (_suboxydum_, _dioxydum_) M_{2}O Oxide, protoxide, or monoxide (_oxydum_, _protoxydum_) MO Sesquioxide (_sesquioxydum_) M_{2}O_{3} Binoxide, dioxide, or deutoxide (_binoxydum_, _deutoxydum_) MO_{2} Teroxide or trioxide (_teroxydum_, _tritoxydum_) MO_{3} {That containing {the _largest_ Peroxide (_peroxydum_) {proportion of {oxygen.

SALTS.——_a._ Acids having names ending in -IC give rise to salts whose names end in ATE; thus _nitr_IC acid yields _nitr_ATES, e.g. _nitrate of silver_. -ATE is Latinised by -AS, e.g. _nitrate of silver_ becomes _argenti nitr_AS.

_b._ Acids possessing names ending in -OUS form salts having names ending in -ITE; thus _sulphur_OUS _acid_ produces _sulph_ITES, e.g. _sulphite of sodium_. -ITE is Latinised by -IS; e.g. _sulphite of sodium_ becomes _sulph_IS.

_c._ The preceding names are presumed to refer to neutral compounds. In _acid_ salts the prefixes noticed above are added to express the preponderance of the acid radical over the metal. KHSO_{4} is called _acid sulphate of potassium_, BI_sulphate of potassium_, or BI_sulphate of potash_, the neutral sulphate being K_{2}SO_{4}.

_d._ In _basic_ salts, or those in which the metal is in excess of the acid radical, the prefixes -SUB and -DI are employed; _e.g._ the formula of _neutral_ acetate of lead is PbĀ_{2}. This salt, when boiled with oxide of lead (a base), furnishes [PbĀ_{2}PbO] and [PbĀ_{2}2PbO]. They are both, therefore, _basic_ acetates; and to distinguish one from the other the former is called DI_acetate_ and the latter TRI_acetate_ of lead; _-di_ referring to the presence of two atoms of lead and _-tri_ to three.

Formerly the salts of the metals of the alkalies and alkaline earths received names which indicated the existence in them of the oxides of such metals. Thus, the terms carbonate of soda, nitrate of potash, carbonate of lime, sulphate of magnesia, names by which these fluids are still designated by some chemists are now substituted by the more systematic and less speculative names of carbonate of sodium, nitrate of potassium, carbonate of calcium, and sulphate of magnesium. Another, and in the opinion of the editor, a still better system of nomenclature is that in which the metallic or basic radical is mentioned first; _e.g._ calcium sulphate instead of sulphate of calcium, ammonium chloride for chloride of ammonium. When the _same_ radicals form more than one series of salts, each series is distinguished by appending the terminations -IC and -OUS to that part of the name which refer to the basic radical; _e.g._ _mercur_OUS _chloride_ (HgCl), _mercur_IC _chloride_(HgCl_{2}); _ferr_OUS _sulphate_ (FeSO_{4}), _ferr_IC _sulphate_(Fe_{2}(SO_{4})_{3}).

NON-METALLIC BODIES, &c. The names of the compounds formed by the union of the non-metallic elements, and certain other bodies, with the metals and with each other, either terminate in -IDE, Latinised by -IDUM, or in -URET, Latinised by -URETUM; as, _arsen_IDE or _arseni_URET (_arsen_IDUM, _arseni_URETUM), _brom_IDE, _carb_IDE or _carb_URET, _chlor_IDE, _cyan_IDE _fluor_IDE, _hydr_IDE, _iod_IDE, _sulph_IDE or _sulph_URET, &c. The first of these terminations now prevails among English scientific chemists. The prefixes already noticed are also employed here.

METALS. The names of the metals (those of them, at least, that have been given during the present century) end in -IUM or (less frequently) in -UM; as _potass_IUM, _sod_IUM, _platin_UM. The Latin names of several of the non-metallic elementary bodies also end in -IUM; as, _iodin_IUM, _nitrogen_IUM, &c.

ALKALOIDS. The names of the organic bases which resemble the alkalies in their properties end either in -IA, -NA, or -INE; as, _morph_IA, _qui_NA, _strychn_INE. These terminations are now limited, as much as possible, to substances exhibiting basic properties, but were formerly very loosely applied.

Many chemists reject the first two terminations, and apply -INE to every substance of this class; as, _morph_INE, _quin_INE, _anil_INE, &c.

OTHER ORGANIC SUBSTANCES. The names of organic radicles generally terminate in -YL; as, _eth_YL, _meth_YL, _benz_OYL, &c.; they mostly contain carbon, hydrogen, and oxygen. Compounds corresponding to the electro-negative elements have the termination -OGEN, as _cyan_OGEN, _amid_OGEN. Neutral compounds of carbon and hydrogen, mostly liquid, have the termination -OL, or -OLE; as, _benz_OL, _pyr_OLE. Other neutral substances, generally solid, have the termination -IN; as, _paraff_IN, _naphthal_IN. Compounds resembling ammonia, and generally considered as ‘substitution compounds’ of that body, terminate in -AMINE; as, _ethyl_AMINE, _propyl_AMINE.

The Latin genitive or possessive of the above compounds in——

-as is -atis -is ” -itis -icum ” -ici -osum ” -osi -idum ” -idi -etum ” -eti -ium ” -ii -um ” -i -ia } -a } ” -æ -na }

_Ex._ Acetas (acetate), acetatis of acetate; arsenis, arsenitis; citricum, citrici; arseniosum, arseniosi; iodidum, iodidi; sulphuretum, sulphureti; sodium, sodii; platinum, platini; morphia, morphiæ; quina, quinæ; narcotina, narcotinæ. The genitives of common names vary with the termination. Most of those ending in -a make æ, and most of those in -us and -um make -i; but there are many exceptions, among which cornu (a horn) and spiritus (spirit) which are unaltered in the genitive singular, may be mentioned as examples.

=NORFOLK FLUID.= _Prep._ Take of linseed oil, 3 pints; black resin, 1/2 lb.; yellow wax, 12 oz.; melt, and add, of neat’s-foot oil, 1 quart; oil of turpentine, 1 pint. Used to preserve and soften leather.

=NOR′IUM.= An unexamined metal, the oxide of which, according to Svanberg, exists in certain varieties of ZIRCON.

=NOS′TRUMS.= See PATENT MEDICINES, &c.

=NOTICES.= The following sections of the Public Health Act refer to serving and delivery of notices under that Statute:

(S. 266.) Notices, orders, and other such documents under the Public Health Act may be in writing or print, or partly in writing and partly in print; and if the same require authentication by the local authority, the signature thereof by the clerk to the local authority or their surveyor or inspector of nuisances shall be sufficient authentication.

(S. 267.) Notices, orders, or any other documents required or authorised to be served under the said Act may be served by delivering the same to or at the residence of the person to whom they are respectively addressed, or where addressed to the owner or occupier of premises, by delivering the same or a true copy thereof to some person on the premises, or if there is no person on the premises who can be so served, by fixing the same on some conspicuous part of the premises; they may also be served by post by a prepaid letter, and if served by post shall be deemed to have been served at the time when the letter containing the same would have been delivered in the ordinary course of post, and in proving such service it shall be sufficient to prove that the notice, order, or other document was properly addressed and put into the post.

Any notice required to be given to the owner or occupier of any premises may be addressed by the description of the ‘owner’ or ‘occupier’ of the premises (naming them) in respect of which the notice is given, without further name or description.

_Enforcing the Drainage of Houses._

(S. 23.) Notice is to be given to the owner or occupier, but in case of the failure of either to comply, and the authority having to do the work, the expenses fall on the owner.

_Insufficient Privy Accommodation._

(SS. 36 and 37.) The same procedure as under the above section.

_The Cleansing and Whitewashing of Houses._

(S. 46.) Notice to the owner or occupier.——

The person on whom the notice is served is liable to a penalty if it is not complied with.

_The Removal of Manure or Filth, &c., in an Urban District._

(S. 49.) Notice to be served on the person to whom the manure belongs, or to the occupier of the premises whereon it exists. If the urban authority have to remove it themselves, the expense of removal falls upon the owner of the manure, &c., or the occupier of the premises, or where there is no occupier, the owner of the premises.

_In the case of Nuisances._

(S. 94.) Notice is to be served upon the person causing or permitting the nuisance to remain, or, if he cannot be found, on the owner or occupier of the premises on which the nuisance arises; but if the nuisance arises from the want or defective construction of any structural convenience, or where there is no occupier, notice is to be served on the owner.

_In the case of Houses, &c., requiring Disinfection._

(S. 120.) Notice is to be given to the owner or occupier, and in case of non-compliance, the person on whom the notice is served is liable to penalties, and the expenses of the authority doing the necessary works falls upon that person (with certain exceptions, in case of poverty).

=NOVAR′GENT.= _Prep._ From recently precipitated chloride of silver by dissolving it in a solution of either hyposulphite of sodium or of cyanide of potassium. Used chiefly to restore old plated goods. The liquid is rubbed over the metal to be coated with a little prepared chalk, and the part is afterwards polished off with a piece of soft leather. A powder recently sold under the same name is formed by mixing the preceding article with chalk, and drying the mass. It is made into a paste with a little water, spirit of wine, or gin, before applying it.

=NOVAUR′UM.= From a solution of neutral trichloride of gold, as the last.

=NOYAU.= _Syn._ CRÈME DE NOYAU. This is a pleasant nutty-tasted liqueur; but from the large proportion of prussic acid which it contains, a small quantity only should be taken at a time.

_Prep._ 1. Bitter almonds (bruised), 3 oz.; spirit (22 u. p.), 1 quart; sugar, 1 lb.; (dissolved in) water, 3/4 pint; macerate for 10 days, frequently shaking the vessel; then allow it to repose for a few days, and decant the clear portion.

2. As the last, but substituting apricot or peach kernels (with the shells, bruised), for the almonds.

3. To either of the above, add of coriander seed and ginger, of each, bruised, 1 dr.; mace and cinnamon, of each 1/2 dr.

4. (Wholesale.) To plain cordial, at 54 to 60 u. p., containing 3 lbs. of sugar per gallon, add, gradually, essence of bitter almonds, q. s. to flavour.

5. (CRÊME DE NOYAU DE MARTINIQUE.) Loaf sugar, 24 lbs.; water, 2-1/2 galls.; dissolve, add, of proof spirit, 5 galls.; orange-flower water, 3 pints; bitter almonds (bruised), 1 lb.; essence of lemons, 2 dr.; as above. See LIQUEURS.

=NUISANCE.= The following are the chief clauses of the Public Health Act respecting nuisances:

_Definition of Nuisances._

1. Any premises in such a state as to be a nuisance or injurious to health.

2. Any pool, ditch, gutter, water-course, privy, urinal, cesspool, drain, or ashpit, so foul as to be a nuisance or injurious to health.

3. Any animal so kept as to be a nuisance or injurious to health.

4. Any accumulation or deposit which is a nuisance or injurious to health.

5. Any house, or part of a house, so overcrowded as to be dangerous or injurious to the health of the inmates, whether or not members of the same family.

6. Any factory, workshop, or workplace (not already under the operation of any general Act for the regulation of factories or bakehouses) not kept in a cleanly state, or not ventilated in such a manner as to render harmless as far as practicable any gases, vapours, dust, or other impurities generated in the course of the work carried on therein that are a nuisance or injurious to health, or so overcrowded while work is carried on as to be dangerous and injurious to the health of those employed therein.

7. Any fireplace or furnace which does not, as far as practicable, consume the smoke arising from the combustible used in such fireplace or furnace, and is used for working engines by steam, or in any mill, factory, dye-house, brewery, bakehouse, or gaswork, or in any manufacturing or trade process whatsoever; and——

Any chimney (not being the chimney of a private dwelling-house) sending forth black smoke in such quantity as to be a nuisance;

Shall be deemed to be nuisances liable to be dealt with summarily under the Public Health Act: Provided——

First. That a penalty shall not be imposed on any person in respect of any accumulation or deposit necessary for the effectual carrying on any business or manufacture, if it be proved to the satisfaction of the court that the accumulation or deposit has not been kept longer than is necessary for the purposes of the business or manufacture, and that the best available means have been taken for preventing injury thereby to the public health.

Secondly. That where a person is summoned before any court in respect of a nuisance arising from a fireplace or furnace which does not consume the smoke arising from the combustible used in such fireplace or furnace, the court may hold that no nuisance is created within the meaning of this Act, and dismiss the complaint, if it is satisfied that such fireplace or furnace is constructed in such a manner as to consume as far as practicable, having regard to the nature of the manufacture or trade, all smoke arising therefrom, and that such fireplace or furnace has been carefully attended to by the person having the charge thereof. (P. H., s. 91.)

The Act also defines and specifies:——1. The duty and powers of a local authority to inspect a district with the view to an abatement of any nuisance. 2. The process of information to be pursued in representing a nuisance to any local authority. 3. Procedure on failing to comply with notice. 4. The power of the court to make an order dealing with such nuisance. 5. The penalty for neglecting to obey such order. 6. The power of complaint by private individuals. 7. The power of the police to proceed in certain cases. 8. The cost and expense of executing the provisions relating to nuisances. 9. The power of sale of manure, &c. 10. The supervision of nuisances caused by drains, privies &c. 11. The proceedings to be taken in certain cases against nuisances in ships, &c.

=NUR′SING.= Milk is the natural food of the mammalia during the earlier period of their existence. It contains all that is necessary for the nourishment of their bodies, and on it they thrive and grow. Its secretion only actively commences at the time when it is required for the sustenance of the offspring, and it either materially lessens in quantity, or wholly disappears, as soon as the necessity of its existence has passed away, and the little being who depended on it has acquired sufficient age and strength to exist on cruder aliment. The nursing mother, when in a state of perfect health, and properly supplied with a sufficiency, without excess, of nutritious food, elaborates this secretion in the fittest condition to ensure the health and vigour of her offspring. Her bosom is the fountain whence flows the beauty and stamina of the future adult, and whilst giving strength and life to another, she increases and prolongs her own.

The milk of woman varies with the food, health, age, &c., of the nurse. That produced from a mixed animal and vegetable diet, neither acesces nor coagulates spontaneously, like cows’ milk; and when gently evaporated in an open vessel, “the last drop continues thin, sweet, and bland.” Acids and rennet, however, coagulate it readily, and so does the gastric juice of the infant, as shown by the condition in which it is often ejected by the latter. The milk of a woman who lives wholly on vegetable food acesces and coagulates with equal readiness and in a precisely similar manner to cows’ milk. The quality of the milk also varies with the progress of the digestion. Within the first hour or two after a meal it is thin and serous, and then gradually improves in richness and flavour, until at about the fourth or fifth hour it possesses these qualities in the highest degree. This, then, is the period at which the infant should be applied to the breast, which, according to the present habits of society, would be during the hour immediately preceding each meal, except the breakfast. After about the fifth or sixth hour the milk gradually loses its peculiar colour and odour, until towards the tenth or twelfth hour after eating food it becomes yellowish, bitter, and often nauseous; and in this condition is frequently refused by the infant. This points out the impropriety of a nurse fasting longer than 4 to 5 hours, except during the night, when the period may be extended to 7 or 8 hours, but never longer. The time after accouchement is another matter that influences the character of human milk in respect of its wholesomeness for the infant. The milk secreted soon after delivery is very thin and serous, but in the course of a few days it becomes thicker, richer, and more nutritious; and a gradual change in the same direction proceeds during the usual period of suckling. When the mother suckles her own infant, or the “age of the milk,” as the nurses say, corresponds to that of the child, all goes on well; but when the former much exceeds the latter, the reverse is the case. Thus, it is found that an infant is incapable of completely digesting the milk of a nurse whose own child is much older than itself; and that an infant of a few weeks old will often starve on the milk intended by nature for one several times its age. It is, therefore, necessary, in selecting a wet-nurse, to be certain that her condition, in this respect, closely corresponds to that of the mother of the infant, or that it does not differ, on this point, more than 3 or 4 weeks. In respect of the use of high-flavoured or improper food and beverages, medicine, &c., it appears that all these substances immediately affect the milk, and impart to it more or less of their peculiar flavour and properties; and, except with remedies administered under medical advice, in nearly all cases prove injurious to the infant. The diet of a nurse should be nutritious and succulent, and its healthy digestion should be promoted by exercise and pure air. Strong liquors, more especially spirits, act like slow poisons on the infant, and their habitual use by a nurse should, therefore, be considered as a positive disqualification for the duties of her office. The care of the mother or wet-nurse should be particularly directed to the maintenance of her own health and equanimity, by which both the health and good temper of the infant will be, as far as possible, ensured. A grieving, irritable, or angry mother forces her bad qualities on her offspring, in the shape of fits, convulsions, or hopeless marasmus. See INFANCY, MILK, INFANTS, FOOD FOR, &c.

=NUT′MEG.= _Syn._ MYRISTICÆ NUCLEUS, NUCISTA, NUX MOSCHATA, N. MYRISTICA, N. AROMATICA, MYRISTICA (B. P., Ph. L.), L. “The shelled seed of _Myristica officinalis_ (Linn.; _M. moschata_——Thunberg),or nutmeg-tree.” It is chiefly used as a spice and condiment, but it is also esteemed as an aromatic in flatulency and diarrhœa.——_Dose_. Half a teaspoonful, or more, grated. The distilled and expressed oils (OLEUM MYRISTICÆ) are also officinal.

Of the different varieties of nutmegs met with in commerce, those known as Penang are the most valuable. Next to these rank the Dutch or Batavian kind, and after these the Singapore nutmegs. In the Dutch or Batavian variety the exterior is composed of a number of white furrows, with brown projections, which aspect is caused by their having been dusted over with lime previous to their exportation. Besides the above, there is also a very inferior description, known as the long or wild nutmeg, which are met with either in the shell, out of the shell, or in the shell with the mace attached.

Nutmegs are subject to the ravages of a worm which would seem to devour or destroy their aromatic principle, since when attacked by this parasite they lose both their odour and taste.

In 100 parts sound nutmegs contain——

Volatile oil 6·0 Liquid fat 7·6 Solid fat 24·0 Acid 0·8 Starch 2·4 Gum 1·2 Ligneous fibre 54·0 Loss 4·0 —————— 100·0 (BONASTRE.)

=NUTRI′′TION.= The phenomena of life are accompanied by the constant and unceasing waste of the materials of which the animal body is composed. Every act of volition, every exertion of muscular power, every functional action of the organism, whether perceptible or imperceptible and involuntary, every play of chemical affinity and decomposition, even thought itself, occasions the disorganisation and destruction, as living matter, of a portion of ourselves. But the process of respiration, and the various important changes with which it is connected, tends, more than all the other vital functions, to waste the substance of the body, the temperature of which it is its special office to support. This loss, this change, which commences with life and terminates only with death, is compensated for by the constant renewal of the whole frame by the deposition and assimilation, or organisation, of matter from the blood, which thus becomes gradually thinner and impoverished, unless, in its turn, it receives a corresponding supply of its vital elements. This it does from the food, which, by the functions of digestion, is converted into a ‘chyle,’ and after being taken up by the ‘lacteals,’ passes into the blood, of which it then becomes a part, and after being animalised and rendered similar to the being it is destined to nourish, by the peculiar action of the vital affinities, it attaches itself to those organs or tissues, the loss of which it is intended to supply. This constitutes nutrition.

The food of animals, or, rather, the nutritious portion of that food on which we live, is wholly organic matter, and is either directly or indirectly produced by the powers of vegetation from the inorganic world. The plant elaborates food for the herbivora, and these, in their turn, serve as food for the flesh-eating animals. In both cases the leading alimentary principles are the same; the difference is in their proportions. Flesh is identical in composition with blood, and with the body of the animal that blood is destined to nourish. It abounds in albumen, casein, and fibrin. The vegetable substances used as food also contain nitrogenised principles of a precisely similar character and chemical constitution to those found in flesh, and which we are, therefore, bound to believe are absolutely the same. The gluten of wheat, when purified from gliadin, presents all the characteristics of pure fibrin. The albumen extracted from vegetable juices, when coagulated by heat, cannot be distinguished from the boiled white of egg in a divided condition. The legumen or vegetable casein of almonds, peas, beans, and many of the oily seeds, bears the most striking resemblance to the casein of milk. These facts clearly show that the leading nitrogenised principles of animal bodies pre-exist in vegetables, and that the substances employed as food must have the same, or nearly the same, chemical composition as the body itself. The striking contrast of animal and vegetable food, as far as this point is concerned, is more apparent than real. The actual difference between the two is to be found in the existence of a large quantity of non-nitrogenised matter (sugar, starch, &c.) in the last, which is not contained in the other——matter which abounds in carbon, and which, by its combustion in the system, serves to support the animal heat at a less sacrifice of the organic fabric. In the flesh-eating animal the waste of the organic tissues is very rapid, and the tax upon the vital energies proportionate; for the temperature of its body is kept up, for the most part, by the burning of the nitrogenised matter of which these tissues are composed.

The process of digestion is that by which the available portions of the food are reduced to a form adapted for absorption by the vessels by which it is introduced into the system. In the flesh-eating animal this process is extremely simple, and consists in the mere comminution of the food by the teeth, and its reduction to the liquid state in the stomach, after which, from the nature of its composition, it is nearly all taken up, and at once conveyed into the blood. In the herbivora, however, the process of digestion is much more complicated, and occupies a longer period. Besides the ordinary principles of flesh, their food contains starch, sugar, gum, &c., mixed with much inert vegetable fibre and other useless substances, from which it must be separated. The first of these supply materials for the waste and growth of the body, the second meet the requirements of respiration, and the last pass unaltered through the alimentary canal.

The nature of the digestive process is not clearly established. The principal objects effected appear to be the conversion of starch, coagulated albumen, fibrin, casein, &c., into a liquid form. It is known that the saliva contains a peculiar principle (ptyalin) resembling diastase, capable of transmuting starch into sugar, and that when a little starch is held in the mouth for a short time this change actually occurs. It is also known that the gastric juice contains a peculiar organic principle named ‘pepsin,’ and that this substance, in conjunction with dilute hydrochloric acid, which is likewise present in the stomach, possesses the property of dissolving the albuminous principles of food. (See PEPSIN.) These changes occur whenever these conditions are established out of the body, and hence it is inferred that the process of digestion is effected by similar means. Of this, however, there is no direct evidence.

The use of food, as already noticed, is twofold. It supplies the materials of nutrition to balance the waste of the tissues continually taking place in the body, and it conveys into the system those elements which, by their chemical combinations, produce heat. To effect this purpose in the most beneficial manner, the food should not only be sufficient in quantity, but the proportions of its nitrogenised and carbonaceous principles should bear such relations to each other as to amply meet the demands of the system for each, without the existence, however, of an undue excess of either.

When the muscular movements of a healthy animal are restrained, a genial temperature kept up, and an ample supply of food containing much amylaceous or oily matter given, an accumulation of fat in the system rapidly takes place; this is well seen in the case of stall-fed cattle. On the other hand, when food is deficient, and much exercise is taken, emaciation results. These effects are ascribed to differences in the activity of the respiratory function. In the first instance, the heat-food is supplied faster than it is consumed, and hence accumulates in the form of fat; in the second, the conditions are reversed, and the creature is kept in a state of leanness by its rapid consumption. The fat of an animal appears to be the provision of nature for the maintenance of life during a certain period under circumstances of privation. Hence it is that a lean animal suffers more from cold than a fat one, and is also sooner starved.

“The origin of fat in the animal body has recently been made the subject of much animated discussion; on the one hand, it was contended that satisfactory evidence exists of the conversion of starch and saccharine substances into fat, by separation of carbon and oxygen, the change somewhat resembling that of the vinous fermentation; it was argued, on the other side, that oily or fatty matter is invariably present in the food supplied to the domestic animals, and that this fat is merely absorbed and deposited in the body in a slightly modified state. The question has now been decided in favour of the first of these views, which was enunciated by Professor Liebig, by the very chemist who formerly advocated the second opinion. By a series of very beautiful experiments, MM. Dumas and Milne-Edwards proved that bees exclusively feeding upon sugar were still capable of producing wax, which was pointed out as a veritable fact.”

Professor Liebig divided the principles found in food into two classes:——plastic elements of nutrition, or flesh-and-blood-making principles; and elements of respiration, or those which, by their decomposition or combustion in the system, generate heat. They are as follows:——

_Elements of Nutrition._ | _Elements of Respiration._ | (Plastic or Nitrogenous.) | (Heat-producing.) ———————— | ———————— Animal flesh | Fat Blood | Starch Vegetable albumen | Gum Vegetable casein | Cane sugar Vegetable fibrin | Grape sugar | Milk sugar | Pectin sugar | Alcohol

This division is in the main warranted by fact, but, no doubt, the nitrogenous elements of food produce heat as well as the non-nitrogenous.

=NUX VOMICA.= _Syn._ KOOCHLA NUT, POISON N., VOMIT N.; NUCES VOMICÆ, NUX VOMICA (B. P., Ph., L., E., & D.), L. “The seed of _Strychnos Nux vomica_, Linn.” (Ph. L.), imported from the East Indies (B. P.). This drug is chiefly known as a violent excitant of the cerebro-spinal system. In small doses, frequently repeated, it is tonic, diuretic, and, occasionally, laxative; in slightly larger ones, it is emetic; and, in large doses, it is an energetic and fearful poison.——_Dose_, 1 to 3 gr.; in paralysis, nervous affections, impotence, chronic dysentery, chronic diarrhœa, &c. Its frequent use is said to render the system proof against the poison of serpents. See STRYCHNINE, its active principle.

=OAK.= The British oak is the _Quercus Robur_ of Linnæus, of which there are two varieties, _Q. peduncata_ and _Q. sessiflora_. The wood of the oak is more durable than that of any other tree, and “for at once supporting a weight, resisting a strain, and not splintering by a cannon shot, it is superior to every other kind.” It, nevertheless, “warps and twists much in drying; and, in seasoning, shrinks about 1-32nd of its width.” Foreign oak is less durable, but more brittle and workable. The bark (OAK BARK; QUERCÛS CORTEX, QUERCUS——B. P., Ph. L., E., & D.) is used as an astringent and febrifuge, in doses of 30 to 120 gr., frequently; an astringent decoction is also made of it, but its chief employment is in tanning leather. The peculiar appearance of old oak or ‘wainscoting’ is given to the new wood by exposing it, whilst very slightly damp, to the fumes of ammonia.

=OAT.= _Syn._ AVENA, L. The common cultivated oat is the _Avena sativa_ (Linn.), a graminaceous plant, of which there are several varieties, as the _Avena sativa alba_, or white oat; _A. s. nigra_, or black oat; the potato oat, &c. Other species are also cultivated, as _Avena nuda_ (Linn.), pilcorn, or naked oat; _A. strigosa_, or Spanish oat, &c. The seed (OATS; CARYOPSIDES, SEMINA AVENÆ CRUDA) form the common horse-corn of this country, but in the northern parts of the country it is extensively used as food for man. The husked grain constitutes GROATS, and its meal OATMEAL. The latter does not form a dough with water, as wheaten meal or flour does.

Oats consist of from 24% to 28% of husk, and 74% to 78% of grain. According to M. Payen, they contain of starch, 60·59%; azotised matter, 14·39%; saccharine and gummy matter, 9·25%; fatty matter, 5·50%; cellulose, 7·60%; silica and saline matter, 3·25%. The husks contain between 6 and 7% of saline matter. (Prof. Norton.) The ash amounts to 2·18%, and consists of potassa and soda, 26·18%; lime, 5·95%; magnesia, 9·95%; oxide of iron, ·40%; phosphoric acid, 43·84%; sulphuric acid, 10·45%; chlorine,·26%; silica, 2·67%; alumina, ·06%. (Johnston.)

The yield of oats is from 20 bushels per acre in poor soils, up to 60, 70, and even 80 bushels per acre in rich soils. The weight per bushel varies from 35 to 45 lbs., and the product in meal is about one half the weight of the oats.

A large proportion of the oats given to horses passes off undigested. It has hence been proposed to prevent this loss, by either coarsely bruising them in a mill, or by pouring boiling water over them, and allowing them to macerate till cold, when they are to be given to the horses without straining off the water. It is stated on good authority that oats thus treated will not only fatten quicker, but go twice as far as without preparation. Oat bruisers are now manufactured by most agricultural implement makers.

Under the microscope the oat is seen to consist of two or three envelopes; the outer being composed of longitudinal cells; the second obliquely transverse and not very clearly seen; in this, the cells are wanting in part or pass into the cells of the third coat; the third envelope consists of a layer, usually single, of cells, like wheat. Before the envelopes are searched for the husks must be removed. The starch-cells are small, many sided, and cohere into round composite bodies, which are very characteristic, and which, by pressure, may be divided into separate grains. A high power is necessary for the examination of these latter. The starch of the oat does not polarise light.

=OAT′MEAL.= _Syn._ AVENÆ FARINA, F. EX SEMINIBUS AVENÆ (Ph. D), L.

Oatmeal is the grain of the oat deprived of the skin, kiln-dried, and afterwards ground. It is regarded as one of the most nutritious of our cereals, being rich in nitrogenous matter, fat, starch, and sugar. According to Letheby it contains in 100 parts:——

Nitrogenous matter 12·6 Carbo-hydrates 63·8 Fatty matter 5·6 Saline matter 3·0 Water 15·0 —————— 100·0

Kreusler has shown that the nitrogenous principle of oatmeal contains gluten-casein, a substance very similar to the legumin of peas and beans. Letheby points out that, although it contains more nutrient material than wheat, its higher price renders it less economical as an article of diet. Oatmeal forms the staple of the food of the farm labourer both in Scotland and in England, being consumed more largely by the Scotch than the English peasant. Scotch oatmeal is superior to English in nutritive value. Oatmeal, when mixed with water, does not possess sufficient tenacity to enable it to be made into bread. It can, however, be baked into excellent cakes, which, when made in Yorkshire, are leavened, and when in Scotland, unleavened.

The qualities of indigestibility and a tendency to produce irritability of the bowels and skin, have been ascribed to oatmeal; before it was so prepared as to effectually remove from it the husk and hairs by efficient screening, it was in Scotland a frequent source of intestinal concretion. These concretions, the nature of which was unravelled by Dr Wollaston, consisted principally of phosphate of lime mixed with the hairs and husks of the oat.

Of thirty samples of oatmeal examined by the ‘Lancet Sanitary Commissioner,’ no fewer than sixteen samples, or more than one half, were adulterated. The substance generally used for this purpose is barley meal, which is only half the price of oatmeal. Husks of barley, wheat, and of the oat itself, are also frequently used. Rice and maize are also sometimes added. That supplied to the army, navy, and the workhouses, was very commonly adulterated with whiting, plaster of Paris, or ground bones. The mineral sophisticant may be detected by the excess of ash, which should not exceed 2·36 per cent. These frauds are readily detected by the microscope.

_Grits_ or _Groats_ are the decorticated grain of the oat, which when bruised or crushed constitute Embden groats. Flummery (known in Scotland as _sowans_) is made by steeping the husks of the grain in water, until they become slightly sour, the strained liquid being boiled down to the consistence of gruel. Oatmeal soon becomes sour and rancid. It should be purchased at such shops as have a quick sale for it. See ACARI, STIR-ABOUT.

=OBE′′SITY.= _Syn._ OBESITAS, POLYSARCA, L. Unhealthy or troublesome fatness or corpulency. Sometimes the secretion of fat, and its accumulation in the adipose membrane, is almost as rapid as that of water in anasarca; on which account some of the old writers have called obesity a dropsy of fat. Persons in easy circumstances, of indolent habits, who live freely, and who are of a cheerful and contented deposition, are those most liable to obesity. The treatment consists in the very gradual reduction of the diet, until it falls rather below the average quantity required by a healthy adult; the very gradual disuse of fermented liquors, more especially beer; the gradual abridgment of the time devoted to repose, until it does not exceed 5 or 6 hours; the employment of several hours daily in exercise in the open air, at first moderate, but increased day by day in energy, until it becomes laborious; and, lastly, arousing the mind from a state of lethargy to one of active or even harassing employment.

In some cases the accumulation of fat has been enormous. Bright, of Maldon, weighed 728 lbs.; Daniel Lambert, of Leicester, 739 lbs.; a girl, 4 years old, noticed in the ‘Phil. Trans.,’ 1813, weighed 256 lbs.

Persons affected with obesity are generally short-lived.

=OBSTRUCTION OF LOCAL AUTHORITY.= Various penalties are mentioned in different sections of the Public Health Act for the offence of obstructing officers, &c., representing the local authority, in carrying out the Act. The following section, which we select, deals with the subject generally:——

Sec. 306. “Any person who wilfully obstructs any member of the local authority, or any person duly employed in the execution of this Act, or who destroys, pulls down, injures, or defaces any board on which any bye-law, notice, or other matter is inscribed, shall, if the same was put up by authority of the Local Government Board or of the local authority, be liable for every such offence to a penalty not exceeding £5.

“Where the occupier of any premises prevents the owner thereof from obeying or carrying into effect any of the provisions of this Act, any justice, to whom application is made in this behalf, shall by order in writing require such occupier to permit the execution of any works required to be executed, provided that the same appear to such justice to be necessary for the purpose of obeying or carrying into effect the provisions of this Act; and if within 24 hours after the making of the order such occupier fails to comply therewith, he shall be liable to a penalty not exceeding £5 for every day during the continuance of such non-compliance.

“If the occupier of any premises, when requested by or on behalf of the local authority to state the name of the owner of the premises occupied by him, refuses or wilfully omits to disclose, or wilfully misstates the same, he shall (unless he shows cause to the satisfaction of the court for his refusal) be liable to a penalty not exceeding £5.”

=O′CHRES.= These are native earthy compounds of clay, coloured with oxide of iron, with frequently a little chalk, or magnesia. The differences in the colour arise partly from the quantity of iron present, and partly from the state of oxidation in which the iron is found. Several varieties are known in commerce——BROWN OCHRE, FRENCH O., OXFORD O., RED O., ROMAN O., YELLOW O. All these, with the exception of the first and fourth, have a yellow colour. ARMENIAN BOLE, INDIAN RED, VENETIAN R., and SPANISH BROWN, are also ochres.

All the ochres are darkened by calcination. The yellow ochres acquire a red or reddish-brown colour by this treatment. The pigment called ‘light red’ is thus prepared from yellow ochre.

=ODONTAL′GIA.= See TOOTHACHE.

=O′DORAMENTS.= _Syn._ ODORAMENTA, L. Substances employed in medicine on account of their odour. They differ from disinfectants, in only disguising, but not destroying, noxious vapours, &c. AMMONIA, STRONG VINEGAR, and PASTILLES, furnish the most familiar examples of this class of substances. See DISINFECTANTS, PERFUMES, &c.

=O′DOUR.= The emanation of an odoriferous or scent-giving body. See PERFUMES.

=ŒNAN′THIC ETHER.= See ETHER (Œnanthic).

=OFFIC′INAL.= _Syn._ OFFICINALIS, L. A term applied to substances or medicines ordered in the Pharmacopœia.

=OIL.= _Syn._ OLEUM, L.; HUILE, Fr. This name is given to numerous liquid or semi-liquid substances, expressed or drawn from animal or vegetable bodies; to various products of the distillation of bituminous minerals; and to several unctuous mixtures in perfumery and pharmacy. To facilitate reference, we have grouped the principal substances generally called ‘oils’ into classes, under the following heads:——OILS (Drying); OILS (Empyreumatic): OILS (Fixed); OILS (Medicated); OILS (Mineral); OILS (Mixed); OILS (Perfumed); OILS (Volatile). See these articles also _below_:——

=Oil, Consol′idated.= _Syn._ CAMPTICON, FACTITIOUS CAOUTCHOUC. A substance having most of the properties of india rubber, prepared by oxidising boiled linseed oil, or any other oil that hardens on exposure to the atmosphere. To obtain the solid oil, plates of glass are dipped into linseed oil, the films are then allowed to dry, and the process is repeated again and again until the plates are coated with many layers of perfectly oxidised oil. Instead of plates of glass, extensive surfaces of prepared cloth are employed when the manufacture is carried out on a large scale. The solid oil, having been scraped or peeled off the surfaces, is worked with a small proportion of shell-lac, by means of a mixing machine with hot rollers, until a material singularly like caoutchouc is produced. The consolidated oil can be rolled on to fabrics, so as to form a waterproof cloth, having the finish and flexibility of rubber-cloth. By the action of heat the consolidated oil may be converted into a hard substance resembling vulcanite and ebonite. Its useful applications appear to be very numerous, but its manufacture has not as yet made much progress.

=OIL-GAS.= A mixture of several gaseous hydrocarbons, obtained by passing common whale fat, resin, the heavy petroleum or shale oil, or the tarry residues left after the distillation of these two latter substances, or other cheap animal oil, through red-hot tubes, or by allowing it to fall in drops on red-hot stones or bricks arranged in an iron retort, or other suitable apparatus. The gas has great illuminating power, requires no purification, and is quite free from the ammoniacal and sulphur compounds which vitiate coal-gas. The sp. gr. of oil-gas varies with the heat employed in its production. It averages from 0·76 to 0·90, but it may rise as high as 1·1.

The composition of coal gas, as given by Payen, is as follows:——

+----------------------------+--------+-----------+ | | | Gas from | | |Oil Gas.| Petroleum | | | | residues. | +----------------------------+--------+-----------| | Olefiant gas and homologues| 22·5 | 17·4 | | Marsh gas | 50·3 | 58·3 | | Hydrogen | 7·7 | 24·3 | | Carbonic oxide | 15·5 | —— | | Nitrogen | 4·0 | —— | +----------------------------+--------+-----------+

=OILS (Drying).= All the fixed oils have an attraction more or less powerful for oxygen, and, by exposure to the air, they either become hard and resinous, or they only thicken slightly, and become sour and rancid. Those which exhibit the first property in a marked degree, as the oils of linseed, poppy, rape, and walnut, are called ‘drying oils,’ and are used as vehicles for colours in painting. The others are frequently termed ‘glutinous’ or ‘non-drying oils.’

The resinifying or drying property of oils is greatly increased by boiling them, either alone or along with some litharge, sugar of lead, or white vitriol, when the product forms the ‘boiled oil’ or ‘drying oil’ (oleum desiccativum) of commerce. The efficacy of the process, according to Liebig, depends on the elimination of substances which impede the oxidation of the oil. The following formulæ are adopted for this purpose:——

1. Linseed oil, 1 gall.; powdered litharge, 3/4 lb.; simmer, with frequent stirring, until a pellicle begins to form; remove the scum, and when it has become cold and has settled decant the clear portion. Dark coloured; used by house-painters.

2. Linseed oil and water, of each 1 quart; white vitriol, in powder, 2 oz.; boil to dryness. Paler than the last.

3. Pale linseed or nut oil, 1 pint; litharge or dry sulphate of lead, in fine powder, 2 oz.; mix, agitate frequently for 10 days, then set the bottle in the sun or a warm place to settle, and decant the clear portion. Very pale.

4. Linseed oil, 100 galls.; calcined white vitriol (‘sulphate of zinc’), in fine powder, 7 lbs.; mix in a clean copper boiler, heat the whole to 285° Fahr., and keep it at that temperature, with constant stirring, for at least one hour; then allow it to cool, in 24 hours decant the clear portion, and in 3 or 4 weeks more rack it for use. Used for varnishes.

5. (Liebig.) Sugar of lead, 1 lb., is dissolved in rain water, 1/2 gall.; litharge, in fine powder, 1 lb., is then added, and the mixture is gently simmered until only a whitish sediment remains; levigated litharge, 1 lb., is next diffused through linseed oil, 2-1/2 galls., and the mixture is gradually added to the lead solution, previously diluted with an equal bulk of water; the whole is now stirred together for some hours, with heat, and is, lastly, left to clear itself by exposure in a warm place. The lead solution which subsides from the oil may be used again for the same purpose, by dissolving in it another lb. of litharge, as before.

6. (Wilks.) Into linseed oil, 236 galls., pour oil of vitriol, 6 or 7 lbs., and stir the two together for 3 hours; then add a mixture of fuller’s earth, 6 lbs., and hot lime, 14 lbs., and again stir for 3 hours; next put the whole into a copper, with an equal quantity of water, and boil for about 3 hours, lastly, withdraw the fire, and when the whole is cold, draw off the water, run the oil into any suitable vessel, and let it stand for a few weeks before using it. Patent.

7. (‘Allg. Polytech. Zeitung.’) Binoxide of manganese (in coarse powder, but not dusty), 1 part; nut or linseed oil, 10 parts; mix, and keep the whole gently heated and frequently stirred for 24 to 36 hours, or until the oil begins to turn reddish. Recommended for zinc paint, but is equally adapted for other purposes for which boiled oil is employed.

_Obs._ There is often a difficulty in obtaining the oils ‘bright’ after boiling or heating them with the lead solutions; the best way, on the small scale, is either to filter them through coarse woollen filtering paper, or to expose the bottle for some time to the sun or in a warm place. On the large scale, the finer oils of this kind are often filtered through Canton-flannel bags. The litharge and sulphate of lead used in the above processes may be again rendered available for the same purpose, by washing them in hot water, to remove adhering mucilage.

=OILS (Empyreumat′ic.)= _Syn._ OLEA EMPYREUMATICA, L. The ’empyreumatic oils’ of the old pharmaceutical writers were oily fluids obtained by the dry distillation of various substances, animal, vegetable, and mineral. But few of them are in use at the present day, though formulæ are given for them in some of the foreign pharmacopœias. Two or three have useful applications in the arts, and it is therefore necessary that we should briefly describe their preparation. When the ingredients are of a liquid or pasty nature, or become so when heated, they are usually mixed with about twice their weight of sand, powdered glass, or other like substance, to divide them, and thus expose them more effectually to the action of the fire. Care must also be taken to provide a well-cooled receiver, which must be furnished with a tube to carry off the non-condensable gases liberated at the same time as the oil. The products of the first distillation are generally purified by rectification, either alone or along with water. In general, they require to be preserved from the light and air.

The following are the principal substances belonging to this class:——

=Oil of Al′oes.= _Syn._ ALOETIC OIL; OLEUM ALOETICUM, L. 1. From Socotrine or hepatic aloes distilled along with sand.

2. (Batavian——Cadet de Gassincourt.) Olive oil, 1 lb.; hepatic aloes and myrrh, of each in powder, 2 oz.; olibanum, 1/2 oz.; distil in a sand bath, from a stoneware retort. Used as an external vermifuge for children; a portion is rubbed 2 or 3 times a day over the umbilical regions.

=Oil of Am′ber.= _Syn._ OLEUM SUCCINI, L. From coarse pieces of amber, distilled in an iron retort, either alone or reduced to powder and mixed with sand. The oil is separated from the fetid liquor and succinic acid which passes over, and rectified along with about 6 times its volume of water, by a gentle heat. It then forms ‘RECTIFIED OIL OF AMBER’ (OLEUM SUCCINI——Ph. L. 1836, O. S. RECTIFICATUM——Ph. D. 1826, O. S. PURISSIMUM——Ph. E. 1841). _Prod._ 20%.

_Prop., &c._ It has a pale yellow colour, a strong, ungrateful odour, and a hot, acrid taste; heat and air blacken and thicken it; it boils at 186° Fahr. Sp. gr. ·758 at 75° Fahr. It is antispasmodic, rubefacient, and stimulant.——_Dose_, 5 to 12 drops, made into an emulsion with mucilage; in hysteria, epilepsy, and convulsive affections. Externally, as a friction, either alone or combined with laudanum or sweet oil, in rheumatism, tic douloureux, hooping-cough, &c.

=Oil of Amber, Oxydated= (_Artificial Musk_). Pat into a cup 1 dr. of oil of amber, and add to it, drop by drop, 3-1/2 fl. dr. of strong nitric acid; let it stand for 36 hours, then separate and wash the resinous matter. Antispasmodic and nervine.——_Dose_, 5 to 10 gr. For children, 1/2 gr. to 1 gr.

=Oil, An′imal.= 1. (Empyreumatic or Fetid; OIL OF HARTSHORN, DIPPEL’S O.; OLEUM ANIMALE EMPYREUMATICUM, O. CORNU CERVI, O. DIPPELII, L.) Chiefly obtained as a secondary product in the manufacture of bone-black. Fetid and dark coloured. Used chiefly to make lampblack.

2. (Ethereal; RECTIFIED OIL OF HARTSHORN; OLEUM ANIMALE ÆSTHERIUM, O. CORNU CERVI RECTIFICATUM, LOCO OLEI ANIMALIS DIPPELII, L.)——_a._ A finer kind of animal oil, made by slowly distilling oil of hartshorn, and collecting only the first portion that comes over. Pale and limpid. Exposure to light discolours it.

_b._ (Ph. Bor.) Fetid animal oil distilled in a sand bath, and the product rectified with four times its volume of water. White, limpid, fragrant. Light discolours it.

_Prop._ The refined product is said to be antispasmodic, anodyne, and diaphoretic.——_Dose_, 5 to 30 drops, in water; in large doses it acts as an irritant poison.

=Oil of Birch.= _Syn._ OLEUM BETULÆ, L. From the inner bark of the birch, by heating it in an earthen pot with a hole in the bottom, to allow the oil to flow through into another jar sunk in the ground and luted to it. Thick, balsamic, fragrant. Used chiefly to dress russia leather.

=Oil of Box-wood.= _Syn._ OLEUM BUXI, O. B. EMPYREUMATICUM (Ph. L. 1746), L. From box-wood sawdust. Reputed resolvent; anodyne, antispasmodic, and diaphoretic.——_Dose_, 5 to 20 drops; in convulsions, epilepsy, gonorrhœa, &c. Externally, in toothache, &c.

=Oil of Bricks.= _Syn._ OLEUM LATERITIUM (Ph. L. 1746), L. From olive oil, mixed with brickdust, and distilled; or, from hot bricks steeped in olive oil, then broken to pieces, and distilled.

=Oil of Bricks (Factitious).= _Syn._ OLEUM LATERITIUM FACTITIUM, L. From linseed oil, 1 lb.; oil of turpentine, 1/2 lb.; oil of bones or of hartshorn and Barbadoes tar, of each 1 oz.; simply stirred well together. This is generally substituted for the preceding in the shops.

=Oil of Cade.= _Syn._ OLEUM CADINUM, L.; HUILE DE CADE, Fr. From the _Juniperus oxycedrus_ or Languedoc juniper. Used as oil of tar, which is commonly sold for it.

=Oil of Coal.= _Syn._ COAL OIL. From the gas-works. See NAPHTHA.

=Oil of Gua′iacum.= _Syn._ OLEUM GUAIACI, O. G. EMPYREUMATICUM, L. From guaiacum shavings or raspings. Reputed balsamic, pectoral, and resolvent.

=Oil of Harts′horn.= Bone oil and rectified bone oil are commonly sold for it, but are inferior to it. See OIL, ANIMAL (_above_).

=Oil, Paper.= _Syn._ RAG OIL, PYROTHONIDÆ; OLEUM CHARTÆ, L. On the small scale, by burning paper on a cold tin plate, and collecting the oil; on the large scale, by the destructive distillation of paper or linen rags. In baldness, toothache, ear-ache, &c.

=Oil, Par′affin.= See OILS, MINERAL.

=Oil, Petro′′leum.= See OILS, MINERAL, PETROLEUM.

=Oil, Rag.= See OIL, PAPER, _above_.

=Oil, Rock.= See NAPHTHA, OILS, MINERAL, PETROLEUM.

=Oil, Shale.= See OILS, MINERAL.

=Oil of Soot.= _Syn._ OLEUM FULIGINIS (Ph. L. 1746), L. From wood-soot. Fetid; reputed antispasmodic and nervine.

=Oil of Tar.= _Syn._ SPIRIT OF T.; OLEUM PINI, O. P. RUBRUM, O. TÆDÆ, O. PICIS LIQUIDÆ, L. By simple distillation from wood-tar. Reddish and strong scented. By one or more rectifications it becomes colourless and limpid. It soon gets thick. Used in ringworm and several other skin diseases, made into an ointment with lard. It is poisonous if swallowed in large doses.

=Oil of Tobac′co (Empyreumatic).= _Syn._ OLEUM TABACI EMPYREUMATICUM (Ph. U. S.), L. From tobacco, in coarse powder, gradually heated in a green-glass retort to dull redness, and kept at that temperature as long as any oil passes over; the oily portion is then separated from the water in the receiver, and kept for use. Highly narcotic and poisonous.

=Oil of Wax.= _Syn._ OLEUM CERÆ, L. From beeswax and sand distilled together; the product is rectified once or oftener. Reputed diuretic.——_Dose_, 3 to 6 drops.

=OILS (Fixed).= _Syn._ FAT OILS, UNCTUOUS O.; OLEA FIXA, O. EXPRESSA, L.; HUILES GRASSES, Fr. The fixed oils are compounds of carbon, hydrogen, and oxygen (oxyhydro-carbons), obtained from the organic kingdom, and characterised by their insipidity, unctuosity, insolubility in water, and being lighter than that fluid. Olive oil, which is obtained from the vegetable kingdom, and spermaceti oil, which is obtained from the animal kingdom, may be taken as types of the rest.

The fixed oils are chiefly found in the fruit and seeds of plants, and in thin membranous cells, forming what is called the adipose tissue, in the bodies of animals. According to their consistence, they may be classed into ‘OILS,’ ‘BUTTERS,’ and ‘TALLOWS,’

_Prop., &c._ Among the best-known properties of the fixed oils are——the permanent stain they give to paper, which they render translucid; their non-volatility at the ordinary temperature of the atmosphere, or at that of boiling water, or, indeed, at any temperature insufficient for their decomposition; their constantly floating on the surface of water when added to it; and, lastly, their inability to mix with that fluid. Some of them, as palm oil and cocoa-nut oil, are solid at ordinary temperatures; but the majority are fluid, unless they have been considerably cooled, when they separate into two portions——the one solid, consisting chiefly of stearin, or some analogous substance, and the other liquid, consisting chiefly of olein or elain. Nearly all of them, when exposed to the air, absorb oxygen rapidly, and either gradually harden or become rancid and nauseous. From the first are selected the ‘drying oil’ used by painters; the last are used as food, in cookery, and for machinery, lamps, &c. The whole of these oils, when heated to their boiling points (500° to 600° Fahr.), suffer decomposition, yielding various hydrocarbons; and when suddenly exposed to a red heat, they furnish a gaseous product (oil-gas), which was formerly employed for illumination. It is owing to this property of oil and liquid fats that candles and lamps give their light. The wick is a gas-producing apparatus in miniature. With the caustic alkalies and water the fixed oils unite to form soap. When some of these oils are absorbed by porous bodies, and thus expose a vastly increased surface to the air, they absorb oxygen with such rapidity as to generate a considerable degree of heat. Paper, tow, cotton, wool, straw, shavings, &c., slightly embued with oil, and left in a heap, freely exposed to the air or sun, often spontaneously inflame. In this way many extensive fires have arisen. The above is more particularly the case with linseed, rape, nut, and olive oil. The first, made into a paste with manganese, rapidly becomes hot, and ultimately inflames spontaneously.

The specific gravities of the fixed oils range between ·865 and ·970, water being 1·000.

_Prep._ The fixed oils, except where otherwise directed, are obtained from the bruised or ground fruit or seed, by means of powerful pressure, in screw or hydraulic presses, and are then either allowed to clarify themselves by subsidence or are filtered. Both methods are frequently applied to the same oil. In some cases the impurities are removed by ebullition with water, and subsequent separation of the pure oil. Heat is frequently employed to increase the liquidity of the oil, and thus lessen the difficulty of its expulsion from the mass. With this object the bruised mass, placed in bags, is commonly exposed to the heat of steam, and then pressed between heated plates of metal. This is always necessary with the ‘butyraceous oils.’

Another method is by boiling the bruised seed in water, and skimming off the oil as it rises to the surface. This is the plan adopted for castor oil in the West Indies.

In a few cases, for medicinal purposes, the bruised mass is mixed with 1/2 its weight, or an equal weight, of alcohol or ether, and after 24 hours’ digestion the whole is submitted to pressure, and the alcohol or ether removed by distillation at a gentle heat. The first menstruum is commonly employed for croton oil on the Continent; the second, for that of ergot of rye.

_Purif._ Several methods are adopted for refining or purifying the fixed oils, among which are the following:——

1. The oil is violently agitated along with 1-1/2 to 2% of concentrated sulphuric acid, when it assumes a greenish colour, and, after about a fortnight’s repose, deposits much colouring matter, becomes paler, and burns with greater brilliancy, particularly if well washed with steam or hot water, and clarified by subsequent repose or by filtration. This answers well for most of the recently expressed vegetable oils. It also greatly improves most of the fish oils.

2. A modification of the last method is to well mix the acid with the oil, then to blow steam through the mixture for some time, and afterwards to otherwise proceed as before.

3. FISH OIL (WHALE, SEAL, &c.) is purified by——

_a._ Violently agitating it with boiling water or steam, by placing it in a deep vessel with perforated bottom, through which high pressure steam is forced for some time; it is afterwards clarified by repose, and filtered through coarse charcoal.

_b._ The oil is violently agitated with a boiling hot and strong solution of oak bark, to remove albumen and gelatin, and next with high-pressure steam and hot water; it is, lastly, dried and filtered.

_c._ The oil, gently heated, is stirred for some time with about 1% of good chloride of lime, previously made into a milk by trituration with water; about 1-1/2% of oil of vitriol, diluted with 20 times its weight of water, is then added, and the agitation renewed and maintained for at least 2 hours; it is, lastly, well washed with steam or hot water.

_d._ Mr Davidson treats the oil first with a strong solution of tan, next with water and chloride of lime, then with dilute sulphuric acid, and lastly, with hot water.

_e._ Mr Dunn’s method, which is very effective, and admirable on account of its simplicity, is to heat the oil by steam to from 180° to 200° Fahr., and then to force a current of air of corresponding temperature through it, under a flue or chimney, until it is sufficiently bleached and deodorised; it is, lastly, either at once filtered or is previously washed with steam or hot water.

_f._ Another method, formerly very generally adopted and still in use, is to violently agitate the oil for some time with very strong brine, or with a mixed solution of blue vitriol and common salt, and then either to allow it to clarify by repose or to filter it through freshly burnt charcoal.

4. ALMOND, CASTOR, LINSEED, NUT, OLIVE, RAPE, and some other vegetable oils, are readily bleached by either of the following processes:——

_a._ Exposure in glass bottles to the sun’s rays, on the leads or roofs of houses, or in any other suitable position, open to the south-east and south. This is the method employed by druggists and oilmen to whiten their castor and linseed oils. 14 to 21 days’ exposure to the sun in clear weather during summer is usually sufficient for castor oil when contained in 2 to 4-quart pale green glass bottles (preferably the former), and covered with white gallipots inverted over them. The oil is filtered before exposing it to the light, as, if only in a slight degree opaque, it does not bleach well. Almond and olive oil are, when thus treated, apt to acquire a slight sulphurous smell; but this may be removed by filtration through a little animal charcoal, or, still better, by washing the oil with hot water.

_b._ Another method employed to decolour these oils is to heat them in a wooden, tinned, or well-glazed earthen vessel along with some dry ‘filtering powder’ (1 to 2 lbs. per gall.), with agitation for some time, and lastly, to filter them in the usual manner through an oil-bag. In this way the West-end perfumers prepare their ‘WHITE ALMOND OIL’ (OLEUM AMYGDALÆ ALBUM), and their ‘WHITE OLIVE OIL’ (OLEUM OLIVÆ ALBUM). Formerly, freshly burnt animal charcoal was used for this purpose, and is still so employed by some houses.

5. Mr Bancroft refines OILS FOR MACHINERY AND LUBRICATING PURPOSES generally, by agitating them with a lye of caustic soda of the sp. gr. 1·2. A sufficient quantity is known to have been added when, after repose, a portion begins to settle down clear at the bottom. About 4% to 8% is commonly required for lard oil and olive oil. After 24 hours’ repose the clear supernatant oil is decanted from the soapy sediment, and filtered.

6. Not only the oils above referred to, but all other oils and fats, may be rendered perfectly colourless by the use of a little chromic acid; or, what is the same, by a mixture of a solution of bichromate of potassa and sufficient sulphuric, hydrochloric, or nitric acid, to seize on all the alkali, and thus liberate the chromic acid.

7. PALM OIL and COCOA-NUT OIL are generally refined and bleached by either chromic acid or chlorine, or by heat:——

_a._ The ‘butyraceous oil’ is liquefied by heat in a wooden vessel, and 7% to 9% of good chloride of lime, previously made into a smooth cream with water, is added, and the whole assiduously stirred until the ingredients appear united; the mixture is then allowed to cool, and is next cut up into small lumps, which are exposed to a free current of air for 2, 3, or even 4 weeks; these are melted in a wooden vessel heated by high-pressure steam circulating through leaden pipes, or in a cast-iron boiler lined with lead, and an equal weight of oil of vitriol (diluted with about 20 times its weight of water) is poured in, and the whole gently boiled until the oil is discoloured and runs clear; the fire is then moderated, and the whole allowed to settle; lastly, the fire is removed, and the oil is left to cool very slowly.

_b._ The process with chromic acid has been already noticed, but is more fully explained _below_.

_c._ The oil, heated to the temperature of about 250° Fahr., is exposed to the action of high-pressure steam, which is continuously ‘blown’ through it for 10 or 12 hours, or even longer. The process is greatly facilitated by the introduction of some chromic acid.

8. Mr Watt’s methods of purifying fats and oils are very effective, more especially for those intended for illumination. They are as follows:——

_a._ (For FISH OILS.) Each ton is boiled for 1/2 an hour with caustic soda, 1/2 lb., previously made into a weak lye with water; or steam is blown through the mixture for a like period; oil of vitriol, 1/2 lb., diluted with 6 times its weight of water, is next added, the whole again boiled for 15 minutes, and allowed to settle for an hour or longer, when the clear oil is run off from the water and sediment into the bleaching tubs; here solution of bichromate of potash, 4 lbs., in oil of vitriol, 2 lbs., previously diluted with water, q. s., together with a little nitric acid and some oxalic acid, are added, and after thorough admixture of the whole, by blowing steam through it, strong nitric acid, 1 lb., diluted with water, 1 quart, is poured in, and the boiling continued for 1/2 an hour longer; a small quantity of naphtha or rectified spirit of turpentine is then mixed in, and the oil is, finally, well washed with hot water, and left to settle.

_b._ (For PALM OIL.) The oil is melted by the heat of steam, and, after it has settled and cooled down to about 130° Fahr., is carefully decanted from the water and sediment into the steaming tubs; here a mixture of a saturated solution of bichromate of potash, 25 lbs., and oil of vitriol, 8 or 9 lbs., is added, and after thorough admixture, hydrochloric acid, 50 lbs., is poured in; the whole is then constantly stirred until it acquires a uniform greenish colour, or is sufficiently decoloured, a little more of the bleaching materials being added if the latter is not the case, after which it is allowed to repose for half an hour to settle; it is next run into a wooden vat, where it is washed, &c., as before.

_c._ (For VEGETABLE OILS.) These are treated with a solution of chromic acid, or with a solution of bichromate of potassa, or some mineral acid, as noticed at No. 6. For COLZA, LINSEED, MUSTARD, NUT, and RAPE OIL, a little hydrochloric acid is added; but for ALMOND, CASTOR, OLIVE OIL, and POPPY OIL, no such addition (at least in excess) is required.

9. RANCID OILS and FATS are recovered by boiling them for about 15 minutes with a little water and calcined magnesia; or, by filtering them through freshly burnt charcoal.

In reference to the above processes, it may be useful to remark, that chlorine, the common bleacher and deodoriser of other substances, cannot be well employed directly in the purification of oils, as certain chemical reactions occur when these substances are brought together, which increase the colour instead of removing it, and are often otherwise injurious. The same remarks apply to the use of the ‘chlorides,’ which frequently fails in unskilful hands, and is, indeed, of questionable utility, except, perhaps, in the case of palm oil. Even charcoal exerts little of its usual energy on the oils, and whilst it removes or lessens their offensive odour, sometimes increases their colour. The addition of 1% or 2% of very pure and recently rectified naphtha or oil of turpentine (camphine) to lamp oil is a real improvement, since it increases its combustibility and its illuminative power.

OILS FOR MEDICAL PURPOSES, as CASTOR OIL, COD-LIVER OIL &c., must not be subjected to any process beyond mere clarification by subsidence, filtration through Canton flannel or porous paper, or, at the utmost, washing with warm water, as otherwise their active and valuable properties, if not wholly removed, will be considerably lessened. See FILTRATION.

_Purity._ The fixed oils vary greatly in their value, and hence the constant inducement which leads the unprincipled dealer to adulterate the more expensive ones with those of a similar character, but of an inferior kind of grade. Various methods are adopted to detect these frauds, among which the following are the most valuable of those capable of general application. Others referring to individual oils will be found under the respective heads.

1. (From the odour.) The method of applying this test is to heat a few drops of the oil under examination in a small porcelain, platinum, or silver spoon or capsule (a watch-glass answers well), and to carefully compare the odour evolved with that arising from a known pure sample of the same kind and quality of the oil similarly treated. The odour of the two, when each is pure, is precisely alike, and immediately suggests the plant or animal from which it has been obtained. The presence of LINSEED, NUT, RAPE, SEAL, TRAIN, or WHALE OIL, is thus readily detected, and the imperfections of the sample, even if pure, rendered much more perceptible.

2. (From the density.)——_a._ According to M. Penot, every oil supposed to come from the same plant, or the same animal, has its own particular density, which, at the same temperature, never deviates more than a few thousandths. To apply this test, the relative density or specific gravity of the sample must be determined. This may be done by means of a thousand-grain bottle or an ordinary ‘AREOMETER,’ or, more conveniently, by an ‘ELAÏOMETER’ or ‘OLEOMETER,’ constructed and graduated for the purpose. ‘Fischer’s ELAÏOMETER’ or ‘OIL-BALANCE’ is much employed on the Continent for this purpose, and is a very useful instrument. On the large scale, the weight of an accurately measured imperial gallon of the oil may be taken.

_b._ M. Lauret, an eminent Parisian chemist, a short time since observed that the variations of the density of an oil from adulteration are rendered much more apparent when it is examined in a heated state. To render this discovery practically available, he plunges an ‘elaïometer,’ graduated for the given temperature, into a small tin cylinder nearly filled with the oil, and then places this in a vessel containing boiling water; as soon as the whole has acquired a uniform temperature, he observes the point on the scale of the instrument at which it floats. This point for——

Colza oil is 0° Fish oil 83° Poppy oil 124° Hemp-seed oil 136° Linseed oil 210°

_c._ By employing a specific gravity bottle or small glass globe, fitted with a stopper in which is hermetically fixed a capillary tube of about 8 or 9 inches in length, we may apply the above principle of M. Lauret with the greatest accuracy. This little apparatus is filled with the oil, and then immersed in boiling water for a sufficient length of time for it to acquire that temperature; it is then removed and weighed. The smallest adulteration is, it is said, in this way immediately detected.

When the density of the given sample has been taken, and the name of the oil used to adulterate it is known, the quantity of the latter present may be approximately determined from the specific gravities by the common method of alligation.[49]

[Footnote 49: See MIXTURES, Arithmetic of.]

3. (Sulphuric-acid test.)——_a._ Heidenreich was the first person who gave a useful and general application to the reactions which occur when oil of vitriol is mixed with the fatty oils. As soon as these substances are placed together, very intense chemical action commences, the temperature of the mixture rises, and the mass becomes coloured. These changes are sufficiently varied in the case of the different oils to furnish us with the means of identifying many of them, and of determining their purity. The method of M. Heidenreich is to lay a plate of white glass over a sheet of white paper; on the glass he places 10 or 15 drops of oil, and then adds to it a small drop of concentrated sulphuric acid (‘oil of vitriol’). The appearances which follow differ with the character of the fatty oil examined, and whether the acid is allowed to act on the oil undisturbed (without stirring) or the two are stirred together with a glass rod. In many cases, as with tallow oil, a peculiar odour as well as a change of colour is developed, and a further means of detection supplied. M. Heidenreich has minutely described these reactions, which, for the most part, closely resemble those given in the table, p. 1129. It is necessary, however, in order to ensure great accuracy, to compare the effect of the reagent on the sample with those which it produces on pure oil of the same kind and character under precisely similar circumstances.

_b._ M. Penot, who has followed up the researches of M. Heidenreich with considerable success, recommends the employment of 20 drops of oil, instead of only 10 or 15; and the use of a small capsule of white porcelain, instead of a plate of glass. He also employs a saturated solution of bichromate of potash in sulphuric acid, which he uses in the same proportion as before; but in this case the oil and the reagent are always stirred together.

The observations of M. Penot have been repeated in many cases by Mr Cooley, and the results, with additions, and rearranged, are given in the table, p. 1129.

“By perusing this table,” writes M. Penot, “it will be observed that the same oil does not, under all circumstances, yield precisely similar results with the same reagent. This depends on the place of growth, the age, and the manner of pressing. If, however, any oil be examined comparatively with a perfectly pure one, the proof of adulteration may be rendered, if not certain, at least probable, by noting the difference. Thus I obtained, by adding 1 part of either whale-train, or linseed oil, or oleic acid, or 10 parts of rapeseed oil, the following results:——

+-------------------+---------------------------------------------------------+ | | REAGENTS. | | +-----------------------------------+---------------------+ | NAME OF OIL. | Sulphuric Acid. | Solution of | | | |Bichromate of Potash.| | +--------------------+--------------+---------------------+ | | _Not stirred._ | _Stirred._ | _Stirred._ | +-------------------+--------------------+--------------+---------------------+ |Rape oil with |More red ground |Brownish-olive|Small reddish lumps | | whale-train oil | than with rape oil| coloured | on a grey ground. | | | | | | |Rape oil with |No perceptible |Olive coloured|Small and more | | linseed oil | difference from | | numerous red lumps | | | the rape oil | | on a very | | | | | dark-green ground. | | | | | | |Rape oil with olein|No perceptible |Greenish brown|Small brownish | | or oleic acid | difference from | | lumps on an | | | the rape oil | | olive-coloured | | | | | ground. | +-------------------+--------------------+--------------+---------------------+

“The adulteration being ascertained as far as is possible, the oil is then tested by endeavouring to discover the adulterating oil, either by reagents or by its odour when gently heated, as before described. This having been found out, small quantities of the suspected oil are added to a perfectly pure oil of the kind under examination. Every mixture is then tested by the reagents, until precisely similar results are obtained as those yielded by the oil under examination. Thus, the proportions of the two mixed oils will be discovered by approximation.” (M. Penot.) A simpler method of finding the proportions of the so mixed oils is referred to above.

4. (From increase of temperature.) M. Maumené proposed the increase of temperature arising from the admixture of monohydrated sulphuric acid (oil of vitriol, sp. gr. 1·845) with the fatty oils as a test of their purity, but a sufficient number of observations have not yet been made to furnish data for a general application of this method. According to MM. Faisst and Knauss, who have re-examined the subject, the following are the results when 15 grammes of oil are mixed with 5 grammes of the acid:

_Rise of Temperature._ Almond oil 72·5° Olive oil 68·0° Poppy oil 127·0° Rape or colza oil 100·0° Linseed oil (with Nordhausen or fuming acid only) 133·0°

The above method is less liable to error when a larger quantity of the substances are thrown together.

5. The presence of FISH OIL in the vegetable oils may be readily detected by passing a stream of chlorine through them; the pure vegetable oils are not materially altered, but a mixture of the two turns dark brown or black.

6. Mr Coleman states that the presence of mineral oils in animal or vegetable oils can be easily detected by two characteristic tests——(1) the fluorescent properties they impart to all animal or vegetable oils. (2) The strongly marked aromatic burning flavour they communicate to mixtures containing them. The first-mentioned property is brought out by smearing a metallic surface, such as tin plate or steel, with the oil, and then viewing it at different angles in the open air or sunlight. Mr Coleman suggests that, in examining a dark-coloured oil, it may first be necessary to refine the sample by successive treatments with concentrated sulphuric acid and weak soda solution or lime water, so small a quantity as 2-1/2 per cent. may then be detected by the bluish colour noticed on viewing the oil at certain angles and by tasting it.

The absence of resin oil must also be proved. Nitric acid is said to be a good test, as the colour developed is much greater than in pure oils. Sometimes it may be detected by the smell. The presence of 10 per cent. of resin or mineral oil in non-drying oils delays their solidification with the nitrate of mercury test.[50]

[Footnote 50: ‘Journal of Applied Chemistry,’ Dec., 1874.]

7. Miss Kate Crane[51] states that the cohesion figures of oils may be usefully employed as tests of the identity and purity of the oils. She says, “A number of experiments on this subject have led her to the conclusion that a little patient practice will teach the eye of the observer in a short time to detect the characteristic differences of the figures. To make these perfect it is necessary to observe the time in forming, for _at different periods_ some varieties form figures very like; but with this precaution each is entirely characteristic.

[Footnote 51: ‘American Journal of Pharmacy,’ iv, 406.]

“It is essential that the dish used, &c., be perfectly clean, so that when filled with water no dust or lint floats upon the surface, as this materially interferes with the perfect formation of the figure.

“A single drop is let fall from a burette or glass rod held steadily above the water, upon the centre of the surface. The experiments made with fixed oils are as follows:——_Poppy-seed oil_ spreads instantly to a large figure, retaining an entire outline, and for a few seconds the surface is unbroken, except the bare intimation of a beaded edge.

“In a few moments little holes appear round the edge, and soon the whole surface is broken in like manner; these increase in size very slowly. In fifteen minutes the edge begins to open, forming indentations, which gradually work their way across the figure. As they increase in length these begin to curve, and in three quarters of an hour have doubled themselves two or three times.

“_Cod-liver oil_ spreads in a large film; a little way from the edge a row of small holes appears, and in a minute or two the surface is covered with them; these gradually enlarge, assuming irregular shapes, soon separated by branching lines.

“_Cod-liver oil_ with _lard oil_ spreads very like the former, but in a few moments the edge opens, and the film separates partly across; in a moment one of the projecting points begins to curve itself towards the centre, bending more and more until it forms a coil; meanwhile a few holes have appeared, which spread irregularly, throwing out projecting points.

“_Castor oil_ spreads instantly, the edge remaining entire; openings appear quickly in thirty seconds, and increase gradually, but unevenly, those nearer the edge being larger, and lengthening out irregularly as they spread. The figure lasts some time.

“_Castor_ with a little _lard oil_ makes a smaller figure, and not nearly so much broken; in five minutes the holes open into each other, and the figure breaks up from the edge.

“A mixture of _castor_ and _poppy-seed oils_ spreads to form a lacework border, but smooths out to an entire edge soon, and within a few seconds openings appear. The figure, in size and general appearance, is more like castor oil alone, but the holes spread less uniformly in a given time, a few being larger, but the greater portion much smaller. In fifteen minutes there is a general tendency to break up.

“_Castor_ with a little _croton oil_ throws out a spray, which in a few moments unites into a thin film. The spray, as it spreads, draws out the inner portion into radiate points, which open into a beautiful network, the centre cohering closely.

“_Croton oil_ throws out, in spreading, a fine spray in advance of the more closely cohering portion, which follows quickly. The outer edge breaks up unevenly into little indentations, the border of the inside portion being quite broken, but gradually becomes nearly entire. The surface, too, has openings, which increase quite rapidly in size, the outer ones being much the larger. In the final breaking up, before the holes open one into another, the outlines are beautifully fringed.

8. “Spontaneous combustion ensues when a handful of cotton waste is embued with oil and placed in an air bath at 130° to 200° F. Boiled linseed oil required 1-1/4 hour; raw linseed oil, 4 hours; lard oil, 4 hours; refined rape about 9 hours.”[52]

[Footnote 52: J. J. Coleman, ‘Journal of Applied Chemistry,’ Dec., 1874.]

Mr Gellatly found that an admixture of 20 per cent. of mineral oil retarded combustion, and 50 per cent. prevented it completely.

M. Burstyn,[53] believing that the value of a fatty oil as a lubricant depends on the amount of acid it contains, has invented a method for volumetrically determining the acidity. The process is as follows:——A tall cylindrical vessel, provided with a ground-glass stopper, and having two marks on it to indicate respectively 100 cubic centimètres, and 200 cubic centimètres, is filled to the first mark with the oil to be tested, and to the second mark with 88 to 90 per cent. alcohol. The cylinder is then closed and well shaken. Equal quantities other than 100 cubic centimètres can be employed without any other change in the process. After standing two or three hours the oil settles, and the clear alcohol, which contains in solution the free acids and a little of the oil, rises to the top perfectly clear; 25 cubic centimètres of the clear alcohol is taken from the top by means of a pipette. A few drops of alcohol extract of turmeric is added, and the acid determined by means of a standard solution of potash, as in acetometry. The change from yellow to brownish red takes place with great sharpness when neutralisation is reached.

[Footnote 53: Ure’s ‘Dictionary of Arts,’ &c.]

The number of cubic centimètres of potash employed, multiplied by four, gives the quantity of normal solution requisite to neutralise the free acid in 100 cubic centimètres of oil. As it is not an individual acid, but a variable mixture of acids, it is not possible to calculate the percentage of acids present. These numbers, however, may be taken as degrees of acidity. For instance, an oil of 3° of acidity is one which contains enough free acid to neutralise 3 cubic centimètres of normal alkali.

If we assume that oleic acid predominates, which in most cases is the fact, 1° of acidity correspond to 0·28 per cent. by weight of oleic acid. The olive oil of commerce has an acidity ranging from 0·4° to 12°. The first passes as very fine, and is called free from acid or salad oil, while the latter is known by smell and taste as very rancid. Oil that has 4° to 6° of acidity has been found to answer very well as a lubricator.

What relation there exists between the degree of acidity and any injurious effect upon metals is shown by the following experiments:——Four shallow vessels of sheet brass, having a surface of 40 square centimètres each, at the bottom, were filled to the depth of 2 millimètres, with oils of different acidity, and exposed to the air at the ordinary temperature. The vessels were soon more or less covered with green fatty salts, and the oil too acquired a green colour. Oil and vessel No. 1 were the only ones in which no change could be perceived. At the end of 3 days the vessels were cleaned with ether and weighed. The following table shows the amounts of action:

Vessel No. 1, filled with oil of 0·8° lost 0·03 gr. ” No. 2, ” 4·6° ” 0·22 ” ” No. 3, ” 7·8° ” 0·36 ” ” No. 4, ” 8·8° ” 0·04 ”

The quantity of metal destroyed, in equal times and under equal conditions, increases with the acidity of the oil.

The table on page 1128, by Mr Bottome, describes the most striking physical properties of some of the principal fixed oils.

⁂ The following are the principal fixed oils met with in commerce, or which are objects of interest or utility:

=Oil of Al′monds.= _Syn._ OLEUM AMYGDALÆ (B. P., Ph. L), O. AMYGDALARUM (Ph. D.), O. AMYGDALI COMMUNIS (Ph. E.), L. “The oil expressed from the kernels.” (Ph. L.) “Bruise the fresh almonds in a stone mortar, then put them into a hempen sack, and express the oil, without heat.” (Ph. E.) The oil of almonds B. P. and of commerce is obtained from either the bitter or sweet almond, but chiefly from the first, on account of their less value, and the marc being employed in the manufacture of essential oil.

_Prop., &c._ Oil of almonds is black, demulcent, emollient, and nutritious; possesses a purely oleaginous taste, and is one of the most agreeable of the fixed oils; when taken in quantity it is mildly laxative; it is little affected by cold, and congeals with difficulty; is soluble in 35 parts of cold and 6 parts of boiling alcohol; ether dissolves it freely. Sp. gr. ·915 to ·918. _Av. prod._ Sweet almonds, 46%; bitter a., 41%.

_Pur._ It is extensively adulterated with poppy, nut, and teel oil, and not unfrequently with refined rape or colza oil. (See _above_.)

=Oil of Bay.= 1. (EXPRESSED O. OF B.; OLEUM LAURI, O. LAURINUM, L.) By expression from either fresh or dried bayberries, as castor oil. Limpid; insipid.

2. (By decoction; BUTTER OF B.; OLEUM LAURI NOBILIS, O. L. VERUM, L.) From the berries, by boiling them in water, and skimming off the oil. Green, buttery; chiefly imported from Italy. Used by the vulgar in bruises, sprains, rheumatism, deafness, &c. _Prod._ 20%.

=Oil of Beech.= _Syn._ OLEUM FAGI, L. From the nuts of _Fagus sylvatica_ (Linn.) or beech mast. Clear; keeps well; when washed with hot water, it is used for salads, and burnt in lamps. Sp. gr. ·9225. _Prod._ 16%.

=Oil of Belladon′na.= _Syn._ OLEUM BELLADONNÆ SEMINUM, O. B. BACCÆ, L. From the seeds or berries of _Atropa belladonna_ or deadly nightshade. Yellow; insipid. Used for lamps in Swabia and Wurtemberg, and as an application to bruises. The marc is poisonous. It freezes at 34° Fahr. Sp. gr. ·9250.

=Oil of Ben.= _Syn._ OIL OF BEHEN; OLEUM BALATINUM. From the seeds of _Moringa pterygosperma_ (ben nuts). Scentless, colourless; keeps long without growing rank; by standing, it separates into two parts, one of which freezes with difficulty, and is hence much used in perfumery.

=Oil of Benne Seed.= See OIL OF GINGELLY.

=Oil of Brazil-nuts.= _Syn._ OLEUM BERTHOLLETIÆ. From the kernels of the fruit of _Bertholletia excelsa_, or Brazil-nuts. An oil of a bright amber colour, congealing at 24° Fahr. Sp. gr. ·917. It has been used as a substitute for olive oil in plasters and ointments.

=Oil of Caca′o.= _Syn._ BUTTER OF C.; OLEUM CACAO CONCRETUM, BUTYRUM CACAO, L. From the seeds of _Theobroma Cacao_, or chocolate nuts, gently heated over the fire, and then decorticated, and pressed between hot iron plates. Sp. gr. ·892.

Column headings:

A. Name of Oil. B. Specific Gravity at 15°C., Water = 1,000. C. Combustibility. Grms. consumed per hour in a Lamp with Wick. D. Freezing Point in degrees Centigrade. E. Colour. F. Taste. G. Smell. H. Limpidity. Time (in seconds) required to trickle a given distance. I. Drying Power.

+-------------+------+----+------+-------------+-------------+------------+------+-------------+ | A. | B. | C. | D. | E. | F. | G. | H. | I. | +-------------+------+----+------+-------------+-------------+------------+------+-------------+ |Plum kernel |0·9127|68 | -9 |Brownish |Amygdalaceous|Very slight | 93 |Non-drying. | | | | | | yellow | | | | | |Rape seed |0·9128|30 | -4 |Yellow |Nauseous |Nauseous | 159 |Non-drying. | |Colza |0·9136|40 | -9·25|Yellow |Nauseous |Nauseous | 162 |Non-drying. | |Cabbage seed |0·9139|48·5| -8 |Yellow |Nauseous |Nauseous | 148 |Non-drying. | |White mustard|0·9142|29·8|-16·25|Light |Pleasant |Very slight | 157 |Non-drying. | | | | | | yellow | | | | | |Ground nut |0·9163| ? | -3 |Pale greenish|Like peas |Like peas |Not |Non-drying. | | | | | | yellow | | |tested| | |Black mustard|0·9170|25 |-17·5 |Yellow |Pleasant |Very slight | 141 |Non-drying. | |Olive |0·9176|62 | -6[54]|Yellow |Sweet |Peculiar | 195 |Non-drying. | |Sweet almond |0·9180|52·8|-21·5 |Amber |Agreeable |None | 150 |Non-drying. | |Horse-radish | | | | | | | | | | seed |0·9187|43 |-16·25|Yellowish |Pleasant |None | 143 |Non-drying. | | | | | | brown | | | | | |Grape seed |0·9202|37 |-16·25|Gold yellow |Sweet |None | 99 |Dries slowly.| |Beech nut |0·9225|50 |-17·5 |Amber |Very sweet |None | 158 |Non-drying. | |Pumpkin |0·9231|43 |-15 |Pale brown |Sweet |None | 185 |Dries slowly.| | | | | | yellow | | | | | |Land-cress |0·9240|42 |-15 |Brownish |Acrid |Disagreeable| 103 |Dries slowly.| | | | | | yellow | | | | | |Hazel nut |0·9242|53·4|-10 |Amber |Sweet |None | 166 |Non-drying. | |Poppy |0·9243|31 |-18[55]|Pale yellow |Flat |None | 123 |Drying. | |Camelina |0·9252|34 |-18 |Yellowish |Peculiar |Peculiar | 119 |Drying. | |Walnut |0·9260|45 |-27·5 |Light yellow |Flat |None | 88 |Drying. | |Sunflower |0·9262|51·8|-16 |Colourless |Sweet |None | 114 |Dries slowly.| |Hemp seed |0·9276|46 |-27·5 |Dark greenish|Disagreeable |Disagreeable| 87 |Drying. | | | | | | yellow | | | | | |Cotton seed |0·9316| ? | -2·5 |Reddish brown|Strong |None |Not | | | | | | | | | |tested|Drying. | |Sesame |0·9320| ? | -5 |Bright yellow|Pleasant, |None |Not |Non-drying. | | | | | | | slightly | |tested| | | | | | | | piquant | | | | |Linseed |0·9347|38 |-27 |Dark greenish|Strong |Disagreeable| 88 |Drying. | | | | | | yellow | | | | | |Wood |0·9358|44 |Not |Green |Unpleasant |None | 73 |Drying. | | | | |noted | | | | | | |Spindle |0·9360|61 |-20 |Reddish brown|Acrid |Slight | 143 |Non-drying. | |Castor |0·9611|47 |-18 |Colourless |Sickly |Very slight |1,830 |Dries slowly.| +-------------+------+----+------+-------------+-------------+------------+------+-------------+

[Footnote 54: Though these oils do not become quite solid till the point indicated is reached, yet they begin to become grainy at +4° C.]

[Footnote 55: Once solidified, this oil does not liquify until the temperature reaches 2°C.]

TABLE _giving the reactions of various_ OILS _with_ SULPHURIC ACID _and with a saturated solution of_ BICHROMATE OF POTASH _in sulphuric acid_. Re-arranged from M. PENOT’s table, with additions, by Mr COOLEY.

⁂ _The result indicated is obtained in each case by the action of_ one drop _of the_ REAGENT _on_ twenty drops of OIL.

---------------------+--------------------------------------------------------+ | REAGENTS | +--------------------------------------------------------+ | | Saturated Solution of | NAME OF OIL | Sulphuric Acid | Bichromate of Potassa | | | in Sulphuric Acid | +------------------+-------------+-----------------------+ | _Not stirred_ | _Stirred_ | _Stirred_ | ---------------------+------------------+-------------+-----------------------+ Almond oil |Greenfinch yellow,| Dirty green |Yellowish, small lumps | |with orange spots | | | | | | | Castor oil |Yellow, with |Little |Slightly green | |slight spots |reaction | | | | | | Cod-liver oil |Deep purple in |Deep purple, |Reddish-brown clots, | (_fine sample |the centre, |passing into |changing to a clear | of pale oil_) |rapidly turning |purple brown,|bright green | |brown, whilst |reddish | | |violet or purple |brown, and | | |clouds or streaks |gradually | | |spread out towards|deepening to | | |the circumference,|an intense | | |the colour of |brown, | | |which remains |approaching | | |minutes after the |black | | |central portion | | | |turned nearly | | | |black | | | | | | | Hemp-seed oil |Small brown lumps |Greenish |Small yellow lumps or | |or clots on a |brown |clots on a green | |yellow ground | |ground | | | | | Linseed oil | | | | (_from the | | | | Upper Rhine_) |Dark reddish brown|Brown small |Brown small lumps on | | |lumps on a |an almost colourless | | |grey ground |ground | | | | | | | | | (_from Paris_) |Reddish brown, |Brown clots |Brown small lumps on a | |less dark coloured|on a green |green ground | | |ground | | | | | | (_English_) |Chestnut brown |Brown clots |Brown lumps on a | | |on a |greenish-grey ground | | |greenish-grey| | | |ground | | | | | | Liver-train oil |Dark red |Dark red |Dark red | | | | | Madia-sativa oil |Slightly reddish |Olive green |Light brown small lumps| |brown underneath | |on an olive-coloured | |a thin greyish | |ground | |film | | | | | | | Black-mustard oil |Bluish green |Olive green |Olive brown | | | | | Neat’s-foot oil |Yellow slight |Dirty brown |Brown spots on a | |spots | |brownish ground | | | | | Nut oil | | | | (_recent_) |Yellowish brown |Clotted, dark|Small brown lumps or | | |brown |clots | | | | | (_one year old_) | Yellow |Dirty brown, |Small brown lumps | | |less dark | | | |coloured | | | | | | (_still older_) |Orange yellow |Dirty brown |Small brownish lumps | | | | | Olein, oleic acid, | | | | lard, or tallow oil |Reddish spots, |Reddish brown|Bright chestnut colour | |with reddish | | | |circles | | | | | | | Olive oil |Yellow |Dirty brown |Olive brown | | | | | (_another | | | | sample_) |Orange yellow |Brownish grey|Brown | | | | | (_from fermented | | | | olives_) |Orange yellow |Brownish grey|Brown | | | | | Poppy oil | | | | (_recent cold | | | | drawn_) |Yellow spots |Olive brown |Small yellow lumps on a| | | |white ground | | | | | (_recent_ | | | | expressed with slight| | | | heat) |Greenish-yellow |Olive brown, |Small yellow lumps on a| |spots |turning more |greenish-grey ground | | |on the green | | (_one year old, | | | | expressed with | | | | heat_) |Greenish spots |Olive green |Small yellow lumps on a| | | |green ground | | | | | Rape or colza oil | | | | (_trade_) |Yellowish-brown |Brownish, |Yellow small lumps on a| |streaks surrounded|turning on |green ground | |by a bluish-green |the olive | | |ring |green | | | | | | (_recent_) |Green |Bluish green |Yellow small lumps on a| | | |green ground | | | | | (_one year old_) |Green |Bluish green |Yellow lumps on a | | | |brighter green ground | | | | | (_one year old, | | | | rough | | | | hot-pressed_) |Green |Olive green |Small yellow lumps, | | | |more numerous, on an | | | |olive-green ground | | | | | Whale-train oil |Small reddish |Resembles |Small, bright, | |lumps on a |wine lees |chestnut-coloured lumps| |brownish ground | |on a brown ground | -------------------------------------------------------------------------------

=Oil, Cas′tor.= _Syn._ RICINI OLEUM (B. P.), OLEUM CASTOREI, O. RICINI (Ph. L., E., & D.), L. “The oil prepared by heat, or by pressure, from the seed” of “_Ricinis communis_, Linn.” (Ph. L.), the _Palma Christi_, or Mexican oil-bush.

The best castor oil (COLD-DRAWN CASTOR OIL; OLEUM RICINI SINE IGNE)is prepared by pressing the shelled and crushed fruit (seed) in hemp bags, in an hydraulic press, and heating the oil thus obtained along with water in well tinned vessels, until the water boils and the albumen and gum separate as a scum; this is carefully removed, and the oil as soon as it has become cold is filtered through Canton flannel, and put into canisters. The commoner kinds are prepared by gently heating the crushed seeds, and pressing them whilst hot. Another method, sometimes adopted, is to put the crushed seed into loose bags, to boil these in water, and to skim off the floating oil.

_Prop._ It is the most viscid of all the fixed oils; when pure it mixes in all proportions with alcohol and ether, and also dissolves, to a certain extent, in rectified spirit, but a portion of the oil separates on standing. Camphor and benzoic acid increase its solubility in spirit. By long exposure to the air it becomes rancid, thick, and is ultimately transformed into a transparent yellow mass; light hastens these changes. Exposed to cold, a solid, white crystalline fat separates from the liquid portion, and when cooled to 0° it congeals into a yellow transparent mass, which does not again liquefy until the temperature rises to about 18° Fahr. Sp. gr. ·9611 to ·9612, at 60°; ·9690, at 55° (Saussure); ·9575, at 77° (Saussure). _Prod._ 38% to 40% (62%——Ure).

_Pur._ Castor oil is sometimes adulterated with rape oil or with lard oil, a fraud which may be detected by its diminished density; and, when the added oil exceeds 33%, by its insolubility in its own weight of alcohol of ·820. In many cases croton oil is added to increase the purgative quality of the mixture. A compound of this kind is vended in gelatine capsules under the name of ‘CONCENTRATED CASTOR OIL,’ the use of which is fraught with danger. “I have heard of several cases in which very violent and dangerous effects were produced by these capsules.” (Pereira.) The best is imported from the East Indies in tin canisters. The oil obtained from the seeds of _Ricinus viridis_ (Willd.), or lamp-oil seeds, is often mixed with or sold for castor oil.

_Uses, &c._ Castor oil is an exceedingly useful mild purgative, particularly when abdominal irritation should be avoided, as in inflammations of the stomach and bowels, pregnancy, surgical operations, &c.——_Dose_, 2 fl. dr. to 1 fl. oz.

=Oil, Cocoa-nut.= _Syn._ COCOA-NUT BUTTER; OLEUM COCOIS NUCIFERÆ, L. By expression from the kernels of the cocoa nut, or fruit of the _Cocos nucifera_.

=Oil, Cod-liver.= _Syn._ MORRHUÆ OLEUM (B. P.), COD-FISH OIL; OLEUM JECORIS ASELLI, O. GADI, O. G. MORRHUÆ, OLEUM MORRHUÆ (Ph. L.), L. “The oil extracted from the fresh liver of the _Gadus morrhua_ by a steam heat or water bath not exceeding 180° Fahr. Yellow.” “The oil prepared from the liver of _Gadus morrhua_, Linn.” (Ph. L.)

The common cod-liver oil of commerce drains from the livers of the cod-fish when freely exposed to the sun, and just beginning to putrefy. It is dark coloured, strong, and nauseous, and is now chiefly employed in this country by the curriers, for dressing leather. It is the ‘OLEUM JECORIS ASELLI FUSCUM’ of Continental writers. Formerly, the less fetid varieties of this crude oil, after the impurities were removed, either by subsidence or filtration, constituted the only cod-liver oil used in medicine. As its employment as a remedy increased, its revolting flavour, and its great tendency to permanently disorder the stomach and bowels, was found, however, to be a serious obstacle to its general use. It was observed that the oil as it exists in the liver of the cod is bland and nearly colourless, and has only a slight fishy, but not a disagreeable flavour. The attention of persons interested was therefore immediately directed to the subject, and improved methods of obtaining the oil were suggested, and ere long adopted on the large scale.

The methods of preparing cod-liver oil are noticed in another part of this work, but we think it advisable to add to these a description of the plan adopted by Messrs Charles Fox and Co., of Newfoundland, Scarborough, and London, the well-known manufacturers and importers of cod-liver oil:——

“The Newfoundland fisheries are entirely carried on in small boats, principally by the hand-line system, and quite close to the shore. The boats go out early in the morning, and return about four o’clock in the afternoon. The fish, on landing, are handed over to a ‘fish-room keeper,’ whose duty it is to split and open the fish, and to deposit the livers in small tubs holding 17 or 18 gallons each. The tubs are soon afterwards collected from the different ‘fish-rooms,’ and conveyed to the manufactory. The livers are here thrown into tubs filled with clean cold water, and, after being well washed and jerked over, are placed on galvanised iron-wire sieves to drain. They are next put into covered steam-jacket-pans, and submitted to a gentle heat for about three quarters of an hour, after which the steam is turned off, cold air again admitted, and the whole allowed to repose for a short time, during which the livers subside, and the oil separates and floats on the top. The oil is then skimmed off into tin vessels, and passed through flannel strainers into tubs, where it is left to subside for about 24 hours. From these the purer upper portion of oil is run into a very deep, galvanized-iron cistern, and again left to clarify itself by defecation for a few days. It is now further refined by carefully passing it through clean and very stout mole-skin filters, under pressure. The transparent filtered oil is received in a clean, galvanised-iron cistern containing a pump, from which the casks are filled for exportation. The latter, before being filled, are carefully seasoned and cleaned, to prevent their imparting either flavour or colour to the pure oil.”

The superiority of the oil prepared as above consists essentially in every part of the process of extraction being performed whilst the livers are fresh, and in no chemical means being adopted to give the oil a factitious appearance. Its natural pale colour is thus preserved from contamination, and its medicinal virtues maintained intact.

Much of the light brown oil of commerce is obtained from _Gadus callarius_ (the dorse). _G. carbonarius_ (the coal-fish), and _G. pollachius_ (the pollack).

_Pur., &c._ “The finest oil,” remarks Dr Pereira, “is that which is most devoid of colour, odour, and flavour. The oil, as contained in the cells of the fresh liver, is nearly colourless, and the brownish colour possessed by ordinary cod-liver oil is due to colouring matters derived from the decomposition (putrefying) of hepatic tissues and fluids, or from the action of the air on the oil (age). Chemical analysis lends no support to the opinion, at one time entertained, that the brown oil was superior, as a therapeutic agent, to the pale oil. Chemistry has not discovered any substance in the brown oil that would confer on it superior activity as a medicine. On the other hand, the disgusting odour and flavour and nauseating qualities of the brown oil preclude its repeated use. Moreover, there is reason to suspect that, if patients could conquer their aversion to it, its free use, like that of other rancid and empyreumatic fats, would disturb the digestive functions, and be attended with injurious effects.”[56]

[Footnote 56: ‘Elem. Mat. Med.,’ &c., 3rd edit., iii, 2339.]

Among the tests of purity, that generally relied on is known as the ‘sulphuric acid test.’ See OILS (Fixed): _Purity_.

DORSE OIL, and other FISH OIL, sold as ‘LIGHT-BROWN COD-LIVER OIL,’ exhibit with this test much lighter reactions, which closely resemble those of LIVER-TRAIN and WHALE-TRAIN OIL.

To detect the presence of combined iodine, upon which, by some, the therapeutic value of cod-liver oil is thought to depend, the sample is saponified by trituration with a little caustic potassa and hot water, the resulting soap cautiously incinerated, the ashes digested with water, and the whole thrown on a filter. The usual tests for iodine may be then applied to the filtered liquid.

The presence of iodine artificially added is best detected by agitating the oil with a little rectified spirit, and then testing this last for iodine. Or, a little solution of starch and a few drops of sulphuric or nitric acid may be at once added to the oil, when a blue colour will be developed if iodine, or an iodide, has been mixed with the sample.

The sp. gr. of the pale oil is ·9230 to ·9238; of the light-brown oil, ·9240 to ·9245; of the dark-brown oil, ·9290 to ·9315. The density is, however, apt to vary a little with the quantity of moisture present.

_Uses, &c._ Cod-liver oil is a most valuable medicine in a great variety of diseases, more especially in glandular indurations and enlargements, scrofula, phthisis, rheumatism, gout, certain cutaneous diseases, amenorrhœa, chlorosis, caries, rickets, &c. To be of service, however, its use must be continued for several weeks, and the oil must be recent.——_Dose_, 1 to 2 table-spoonfuls, 3 or 4 times daily, or oftener.

=Oil, Col′za.= From the seeds of _Brassica campestris_, var. _oleifera_, or _colza de printemps_, a variety of _Brassica campestris_ (Linn.). It may be regarded as a superior sort of rape oil. Burns well in lamps, especially after being refined. Sp. gr. ·9136. _Prod._ 39%. The term ‘colza oil’ is commonly applied to ordinary refined rape.

=Oil, Cottonseed.= _Syn._ OLEUM GOSSIPII SEMINUM, L. From the seeds of _Gossypium Barbadense_. Drying.

=Oil, Croton.= _Syn._ CROTONIS OLEUM (B. P.), OLEUM CROTONIS (Ph. E.), O. TIGLII (Ph. L.), L. From the shelled seeds of _Croton tiglium_ or Molucca grains. Imported chiefly from the East Indies. It is one of the most powerful cathartics known, and acts when either swallowed or merely placed in the mouth. Externally, it is a rubefacient and counter-irritant, often causing a crop of painful pustules, like tartar emetic.——_Dose_, 1 to 2 drops, on sugar; in apoplexy, &c. It is poisonous in larger doses. Sp. gr. ·947 to ·953. _Prod._ Unshelled seeds, 22% to 25%; shelled do., 32% to 35%.

Pure croton oil is soluble in an equal volume of alcohol of ·796, but in 2 or 3 days about 96% of the oil separates. In France the marc is exhausted with alcohol, and the oil thus obtained is added to that previously obtained from the same seeds by expression. The East Indian oil (OLEUM CROTONIS EXOTICUM) is usually of a pale yellow; that pressed in England (O. CROTONIS ANGLICANUM) is much darker.

=Oil of Cu′cumber.= _Syn._ OLEUM CUCURBITÆ, L. From the seeds of _Cucurbita pepo_ or squash, and the _C. melopepo_ or pumpkin. Pale; used in lamps; and, sometimes, as a soothing application to piles. Sp. gr. ·9231. _Prod._ 24%.

=Oil of Eggs.= _Syn._ OLEUM OVI, O. O. VITELLI, O. OVORUM, L. From the yolks of eggs, gently heated until they coagulate and the moisture has evaporated, and then pressed or broken up, digested in boiling rectified spirit, the tincture filtered whilst hot, and the spirit distilled off. Bland; emollient. The common plan is to fry the yolks hard; but the oil is then darker coloured and stronger. The P. Cod. orders them to be exhausted with ether, by displacement. Formerly commonly used to ‘kill’ quicksilver, and still held in great esteem in some parts of England for sore nipples and excoriations. _Prod._ 10 to 12 eggs yield 1 oz. See MIXED OILS.

=Oil of Garden Cress.= _Syn._ OLEUM LEPIDII SATIVI, L. From the seed. Drying. Sp. gr. ·9240. _Prod._ 54%.

=Oil of Gar′den Spurge.= _Syn._ OLEUM LATHYRIS, O. EUPHORBIÆ L., L. From the seeds of _Euphorbia lathyris_ or garden spurge. Cathartic.——_Dose_, 3 to 8 drops. Sp. gr. ·9281. _Prod._ 30% to 41%. Croton oil mixed with 6 times its weight of nut or rape oil is usually sold for it.

=Oil of Gingel′ly.= _Syn._ OIL OF SESAMUM, BENNE OIL, TEEL O., TEL O.; OLEUM SESAMI, L. From the seeds of _Sesamum orientale_ (Willd.), or gingelly. Pale; bland. Used in salads, paints, &c.; also to adulterate oil of almonds. _Prod._ 46%.

=Oil, Gourd.= See OIL OF CUCUMBER.

=Oil of Ground Nuts.= From the nuts of _Arachis hypogæa_. Glutinous.

=Oil of Gurgun.= See BALSAM, GURGUN.

=Oil of Hemp.= _Syn._ OLEUM CANNABIS, L. From the seed of _Cannabis sativa_ (Linn.), or common hemp. Mawkish. Sometimes used for frying, but chiefly for paints, soaps, &c. Freely soluble in boiling alcohol; does not thicken until cooled to 5° Fahr. Sp. gr. ·9276. _Prod._ 18% to 24%.

=Oil of Jatro′pha.= _Syn._ OIL OF WILD CASTOR SEEDS; OLEUM JATROPHÆ, L. From the seeds of _Jatropha purgans_. Somewhat resembles CROTON OIL. Used for lamps in the East Indies.

=Oil, Kundah.= _Syn._ TALLICOONAH O.; OLEUM TOULOUCOUNÆ, L. From the fruit of _Carapa Touloucouna_. Rancid, nauseous, vermifuge, rubefacient, emetic, and purgative. Chiefly used in lamps.

=Oil, Lard.= _Syn._ TALLOW O., CRUDE OLEIN, C. OLEIC ACID; OLEUM ADIPIS, L. By separating the olein of lard from the stearin by means of boiling alcohol. Only applicable where spirit is cheap. The product is, however, excellent. The crude oleic acid, or lard oil of commerce, is chiefly obtained as a secondary product in the manufacture of stearin. It is purified by agitation with sulphuric acid, and subsequently by steaming it, or washing it with hot water. Burns well in lamps, if the wick-tube is kept cool. Sp. gr. ·9003.

=Oil, Linseed.= _Syn._ OLEUM LINI (B. P., Ph. L., E. & D.), L. 1. (COLD-DRAWN LINSEED OIL; OLEUM LINI SINE IGNE.) From the seed of _Linum usitatissimum_ (Linn.), or common flax, bruised or crushed, and then ground and expressed without heat. Pale, insipid, viscous; does not keep so well as the next. _Prod._ 17% to 20%.

2. As the last, but employing a steam heat of about 200° Fahr. Amber coloured; less viscous than the last; congeals at 2°; soluble in 5 parts of boiling and 40 parts of cold alcohol. Both are drying and cathartic.——_Dose_, 1 to 2 oz.; in piles, &c. Chiefly used in paints, varnishes, &c. Sp. gr. ·9347. _Prod._ 22% to 27%.

3. (BOILED LINSEED OIL.) See OILS (Drying).

=Oil of Mace (Expressed).= See OIL OF NUTMEG (Expressed).

=Oil of Male Fern.= See EXTRACT OF MALE FERN.

=Oil of Mustard.= _Syn._ OLEUM SINAPIS, L. 1. (OIL OF WHITE MUSTARD.) From _Sinapis alba_, or white mustard, but chiefly from _Sinapis arvensis_, _S. chinensis_, _S. dichotoma_, _S. glauca_, _S. ramosa_, and _S. tori_. Sweet. Used for the table. Sp. gr. ·9142 (·2160——Ure). _Prod._ 36%.

2. (OIL OF BLACK MUSTARD; OLEUM SINAPIS NIGRI, L.) From the ‘hulls’ of black-mustard seed. Viscid, stimulant. Used in rheumatism, Sp. gr. ·9168 to ·9170. See OILS (Volatile).

3. (OIL OF WHITE MUSTARD; OLEUM RAPHANI, L.) From the seed of _Raphanus raphanistrum_ (Linn.), or jointed charlock or wild mustard. _Prod._ 30%.

=Oil, Neat’s-foot.= _Syn._ NERVE OIL, TROTTER O.; OLEUM BUBULUM, O. NERVINUM, AXUNGIA PEDUM TAURI, L. From neat’s-feet and tripe, by boiling them in water, and skimming off the oil. Does not thicken by age. Used to soften leather, to clean fire-arms, and for other purposes.

OIL, NUT. _Syn._ HAZEL-NUT O.; OLEUM NUCIS, O. CORYLI, L. From the kernels of _Corylus Avellana_ (Linn.), or hazel-nut tree. Pale, mild tasted, drying; superior to linseed oil for paints and varnishes. It is commonly sold for oil of almonds and oil of ben, and is extensively employed to adulterate both. Walnut oil is also frequently sold for nut oil. Sp. gr. ·9260. _Prod._ 63%(Ure).

=Oil of Nut′meg (Expressed).= _Syn._ EXPRESSED OIL OF MACE, BUTTER OF M.; OLEUM MYRISTICÆ (CONCRETUM) (Ph. L.), MYRISTICÆ ADEPS (Ph. E.), M. BUTYRUM, O. MYRISTICÆ EXPRESSUM (B. P.), O. MOSCHATÆ, O. NUCISTÆ, L. “The concrete oil expressed from the seed of _Myristica officinalis_,” Linn. (Ph. L.), or common nutmeg. The nutmegs are beaten to a paste, enclosed in a bag, exposed to the vapour of hot water, and then pressed between heated iron plates. Orange coloured, fragrant, spicy; butyraceous, or solid. It is a mixture of the fixed and volatile oils of the nutmeg. When discoloured and hardened by age, it is called ‘BANDA SOAP’ (OL. MACIS IN MASSIS). When pure, it is soluble in 4 parts of boiling alcohol and in 2 parts of ether. It has been used in rheumatism and palsy, but is now chiefly employed for its odour and aromatic qualities. From the East Indies. _Prod._ 17% to 20%.

=Oil, Ol′ive.= _Syn._ SALAD OIL, SWEET O.; OLIVÆ OLEUM (B. P.), OLEUM OLIVARUM, O. OLIVÆ (Ph. L., E., & D.), L. The “oil expressed from the fruit” of “_Olea europœa_, Linn.” (Ph. L.), or common olive. Five different methods are employed to obtain the oil, from the fruit:

1. (VIRGIN OIL; O. O. VIRGINEUM, L.); (HUILE VIERGE, Fr.) From olives, carefully garbled, either spontaneously or only by slight pressure, in the cold. That yielded by the pericarp of the fruit is the finest.

2. (Ordinary ‘FINE OIL,’) This is obtained by either pressing the olives, previously crushed and mixed with boiling water, or by pressing, at a gentle heat, the olives from which the virgin oil has been obtained. The above processes furnish the finer salad oils of commerce. The cake which is left is called ‘GRIGNON,’

3. (SECOND QUALITY.) By allowing the bruised fruit to ferment before pressing it. Yellow; darker than the preceding; but mild and sweet tasted. Much used for the table.

4. (‘GORGON.’) By fermenting and boiling the pressed cake or marc in water, and skimming off the oil. Inferior.

5. (OIL OF THE INFERNAL REGIONS; OLEUM OMPHACINUM) is a very inferior quality of oil, which is skimmed off the surface of the water in the reservoirs into which the waste water which has been used in the above operations is received, and allowed to settle. The last two are chiefly used for lamps, and in soap-making, &c.

Of the principal varieties of olive oil known in commerce, and distinguished by the place of their production, ‘PROVENCE OIL’ is the most esteemed; ‘FLORENCE OIL’ and ‘LUCCA OIL’ are also of very fine quality; ‘GENOA OIL’ comes next, and then ‘GALLIPOLI OIL,’ which forms the mass of what is used in England; ‘SICILY OIL,’ which has a slightly resinous flavour, is very inferior; and ‘SPANISH OIL’ is the worst imported.

_Prop., &c._ Olive oil is a nearly inodorous, pale greenish-yellow, unctuous fluid, with a purely oleaginous taste, peculiarly grateful to the palate of those who relish oil. It does not suffer active decomposition at a heat not exceeding 600° Fahr.; and when cooled to 36°it congeals into a granular solid mass. It is very slightly soluble in alcohol, but its solubility is increased by admixture with castor oil. It is soluble in 1-1/2 part of ether. When pure it has little tendency to become rancid. Sp. gr. ·9170 to ·9173; ·9192, at 53-1/2° (Saussure); ·9176, at 59° (Heidenreich); and ·9109, at 77° Fahr. (Saussure). _Prod._ 32%, of which 21% is furnished by the pericarp, and the remainder, which is inferior, by the seed and woody matter of the fruit.

_Pur._ Olive oil, with the exception of that of almonds, being the most costly of the ordinary fixed oils of commerce, is, consequently, the one most subject to adulteration. Nut, poppy, rape, and lard oil, are those most commonly used for this purpose. Refined tallow olein, including that obtained from the ‘knackers’ yards’ of Paris, is said to have been used in the same way. The addition of any other oil to olive oil renders it far less agreeable to the palate, and, by increasing its tendency to rancidity, much more likely to offend and derange the stomach and bowels of those who consume it. Parties who indulge themselves in the use of this luxury would, therefore, do well to ascertain that what they purchase is pure. When pure, and also fresh, olive oil is most wholesome as an article of food or us a condiment.

The detection of the sophistication of salad oil is a matter of no great difficulty. The palate of the connoisseur will readily perceive the slightest variation in the quality of his favourite condiment. Other methods, however, of a more accurate and certain description, and of more general application, are adopted. Amongst these, in addition to those mentioned above, are the following:——

_a._ When pure olive oil is shaken in a phial, only half filled, the ‘bead’ or bubbles rapidly disappear; but if the sample has been mixed with poppy or other oil, the bubbles continue longer before they burst.

_b._ Olive oil congeals at 36° Fahr., and is completely solidified when a small bottle containing it is surrounded by ice, or a freezing mixture; but when mixed with poppy oil, it remains partly liquid, even when the latter forms only 1-4th of the mass; if more than 1-3rd of poppy oil is present, it does not solidify at all, unless cooled much below the freezing point of water.

_c._ (Ph. E.) When olive oil is “carefully mixed with 1/12th part of its volume of a solution of 4 oz. of mercury in 8 fl. oz. 6 dr. of nitric acid (sp. gr. 1·500), it becomes in 3 or 4 hours like a firm fat, without any separation of liquid oil.”

_d._ M. Pontet recommends the mercurial solution to be made by dissolving 6 parts of mercury in 7-1/2 parts of nitric acid (sp. gr. 1·35), without heat; of this solution he adds 1 part to every 48 parts of the oil, and well shakes the mixture every 30 minutes, until it begins to solidify. This it does after about 7 hours in summer and 4 or 5 hours in winter, and when the oil is pure it will have formed, in 24 hours, a mass so hard that some little force must be employed to thrust a glass rod into it. The other edible oils do not furnish a hard mass with nitrate of mercury. The solidity of the mass is exactly in proportion to the quantity of foreign oil present. When the sophistication is equal to 1-8th of the whole, a distinct liquid layer separates; when the mixture contains half its volume of an inferior oil, one half only of the mixture becomes solid, and the other half continues liquid. A temperature of about 90° Fahr. is the best to cause the oil and coagulum to separate perfectly from each other. When the oil has been adulterated with animal oil, the mixture solidifies in about five hours; but in this case the coagulum consists of the animal oil, whilst the olive oil floats on the surface, and may be decanted for further examination. This coagulum, on being heated, exhales the well-known odour of rancid fat or melted tallow.

_e._ Dr Ramon Cordina Langlies states that the best reagent for the examination of olive oil is that of Hauchecorne.

This reagent is composed of three parts of pure nitric acid at 40° with one part of distilled water. The following is Dr Langlies’ process for proving that olive oil does not contain seed oil, and more especially cotton oil:——

He mixes three grammes of the oil to be tested with one gramme of the reagent in a test tube, or a small stoppered flask, and heats the liquid in a water bath. If the oil is pure the mixture becomes clearer, and takes a yellow colour, like purified oil; if it is adulterated with seed oil, it acquires the same transparency as the pure oil, but becomes red. With 5 per cent. of seed oil the reddish colouring is characteristic; with 10 per cent. it is decided. The reaction does not require more than from 15 to 20 minutes.

The colouring of the oils lasts for three days.

_Uses, &c._ The dietetical uses of olive oil are well known. In Spain and Italy it is commonly employed as a substitute for butter. It is highly nutritious, but is digested with difficulty by some persons, and hence should be avoided by the dyspeptic. Like almond oil, it is occasionally employed as a laxative and vermifuge, and is, perhaps, one of the mildest known. In _pharmacy_ it is extensively employed in the preparation of cerates, liniments, ointments, and plasters.——_Dose._ For an adult, 1/2 to 1 wine-glassful as a mild aperient; for an infant, 1/2 to 1 teaspoonful, mixed up with an equal quantity of honey, syrup of roses, or syrup of violets. The white fibrous sediment which forms in the recently expressed oil is the ‘AMURCA’ of Pliny, and was formerly highly esteemed in medicine.

=Oil, Olive, Droppings.= _Syn._ SWEET-OIL D. The ‘foots’ or ‘deposits,’ and the ‘drippings’ of the casks, cisterns, and utensils. Used for machinery, making soap, &c.

=Oil, Olive (Oxygenated).= _Syn._ OLEUM OLIVÆ OXYGENATUM (Ph. Batav.), L. Olive oil, 16 oz., is placed in a receiver surrounded with ice or very cold water, and chlorine is slowly transmitted through it for several days, or until it becomes thick and viscid, after which it is well washed with warm warm.

=Oil, Palm.= _Syn._ PALM BUTTER; OLEUM PALMÆ;, L. From the fruit of _Elais Guineensis_, and _E. melanococca_, the Guinea oil palms. Orange or red coloured; butyraceous or solid; smells of violets; unchanged by alkalies; bleached by sunlight, age, exposure, chlorine, chromic acid, and oil of vitriol; melts at 117-1/2° Fahr. Sp. gr. ·968. Demulcent. Used to colour and scent ointments, pomades, &c.; but chiefly to make soap and candles. From Africa.

=Oil, Pi′′ney.= _Syn._ PINEY TALLOW, P. DAMMAR, P. RESIN. From _Vateria Indica_ (Linn.) or pænoe tree. Resinous flavoured, fragrant, made into candles. Sp. gr. ·926.

=Oil, Pop′py.= _Syn._ OLEUM PAPAVERIS, L.; OLIETE, HUILE BLANCHE, Fr. From the seeds of _Papaver somniferum_ (Linn.), or white poppy. Sweet; pale; dries and keeps well. Used for salads, paints, and soaps; also (extensively) to adulterate almond oil, for the inferior qualities of which it is frequently sold. It does not freeze until cooled to 0° Fahr. Sp. gr. ·9243 to ·9245. _Prod._ 48% to 54%.

=Oil of Pumpkin.= _Syn._ OLEUM CUCURBITÆ. Expressed from the seeds of the pumpkin; a soothing application to piles.

=Oil, Rape.= _Syn._ COLZA OIL, BROWN O.; OLEUM RAPÆ, L. From the seed of _Brassica napus_ (Linn.; cole or rape), and from _Brassica campestris_ (Linn.; wild navew or rape). Glutinous; buttery at 25° Fahr. Dries slowly; makes soft soaps and good ointments, but bad plasters; smokes much in burning, unless well refined. Sp. gr. ·9135 to ·9136. _Prod._ 32%.

OIL, REFINED or PALE RAPE (OLEUM RAPÆ REFINUM, OL. R. ALBUM) is prepared from crude rape oil, by agitating it with about 2% of oil of vitriol, previously diluted with about twice its weight of water, and, after 10 or 12 days’ repose, decanting the clear oil, and filtering it through Canton flannel or felt. The quality is improved by washing it with hot water or steam before filtration. Used for lamps, blacking, and machinery; also extensively employed to adulterate both almond and olive oil. It forms the common ‘SWEET OIL’ of the oilmen and druggists. Sp. gr. ·9136 to ·9140.

=Oil, Seal.= _Syn._ OLEUM PHOCÆ, L. From the hood seal, and harp seal, and other species of _Phocidæ_. PALE SEAL OIL is that which drains from the blubber before putrefaction commences, and forms about 60% of the whole quantity of oil obtained. It is very clear, free from smell, and, when recently prepared, not unpleasant in its taste. REFINED SEAL OIL is the last, washed and filtered. Ranks close after sperm oil. BROWN or DARK SEAL OIL is that which subsequently drains from the putrid mass. It is very strong-scented and nauseous, and smokes in burning. Both are used for lamps and dressing leather. A full-grown seal yields 8 to 12 galls. of oil; a small one, 4 to 5 galls.

=Oil of Ses′amum.= _Syn._ OIL OF GINGELLY (_above_).

=Oil, Shark-liver.= The lightest of the fixed oils. Sp. gr. ·865 to ·867.

=Oil, Skate.= _Syn._ OLEUM RALÆ, L. From the livers of _Raia batis_ (Linn.), or common skate, as cod-liver oil; also from _Raia rhinobatus_, or white skate, and _Raia clavata_, or thornback. Often sold and mixed with cod-liver oil.

=Oil, Spermace′ti.= _Syn._ SPERM OIL; OLEUM CETACEI, L. From the ‘head matter’ of _Physeter macrocephalus_, or spermaceti whale; a species once common in all the principal seas, but now chiefly confined to the Southern Ocean. It is very limpid, smells little, and burns well; and has long been reputed the best oil for lamps and machinery, as it does not thicken by age or friction. It is frequently adulterated with refined seal oil. Sp. gr. ·875.

=Oil, Sun′flower.= _Syn._ OLEUM HELIANTHI, L. From the seeds of _Helianthus annuus_ and _H. perennis_. Clear, pale yellow, tasteless; thickens at 60° Fahr. Used for salads and lamps. Sp. gr. ·9261. _Prod._ 15%.

=Oil, Teel.= See OIL, GINGELLY.

=Oil, Tobac′co-seed.= _Syn._ OLEUM TABACI (EXPRESSUM), L. From the seeds of _Nicotiana tabacum_ (Linn.), or true tobacco plant. Pale; dries well; equal to nut oil. Its production has recently been carried on with considerable success in some parts of Russia. Sp. gr. ·9232.

=Oil of Touloucou′na.= See OIL, KUNDAH.

=Oil, Train.= See OIL, WHALE.

=Oil, Wal′nut.= _Syn._ OLEUM JUGLANDIS, O. NUCIS J., L. From the kernels of the nuts of _Juglans regia_ (Linn.), or common walnut tree. Soon gets rank; dries well. Used in paints, and occasionally in plasters. When ‘cold drawn’ and washed it is sometimes eaten with salad. Sp. gr. ·9260 to ·9262. _Prod._ 48% to 52%.

=Oil of Wax.= _Syn._ BUTTER OF WAX; OLEUM CERÆ, L. From beeswax, by quick distillation in a close vessel. Butyraceous. By rectification along with quicklime it yields a liquid oil.

=Oil, Whale.= _Syn._ TRAIN OIL, WHALE-TRAIN O.; OLEUM BALÆNÆ, O. CETI, L. From the blubber of the _Balæna mysticetus_ (Linn.), or the common or Greenland whale, by heat. Coarse; stinking. SOUTHERN WHALE OIL is the best. Used for lamps, machinery, &c. Sp. gr. ·9231. _Prod._ per fish, about 1-1/2 ton for each foot of bone.

=Oil of Wheat.= _Syn._ OLEUM TRITICI, L. From bruised Colne wheat, with heat. In chilblains, ringworm, and several other skin diseases.

=Oil of Wine-stones.= _Syn._ GRAPE-STONE OIL; OLEUM VITIS VINIFERÆ LAPIDUM, L. From the seeds of grapes, separated from the marc. Pale yellow, bland, emollient. Used for salads and lamps. Sp. gr. ·9202. _Prod._ 14% to 18%.

⁂ The numbers given above, under ‘products,’ unless when otherwise stated, refer to the respective fruits, kernels, nuts, seeds, &c., deprived of their husks, pods, shells, and every other portion destitute of oil.

=OILS (Medicated).= _Syn._ OLEA COCTA, O. INFUSA, O. MEDICATA, L. These are prepared by infusion or decoction. The bruised ingredients are either simply digested in 2 to 4 times their weight of olive oil for some days, or they are gently boiled in it until they become dry and crisp, great care being taken that the heat towards the end of the process is not greater than that of boiling water. As soon as the process is complete, the oil is allowed to drain from the ingredients, which are then (if necessary) submitted to the action of the press. The product is commonly run through flannel or a hair sieve whilst still warm, after which it is allowed to repose for a week or ten days, when the clear portion is decanted from the dregs. The green or recent plants are usually employed for this purpose, but, in many cases, the dried plants, reduced to powder, and digested for 6 or 8 hours in the oil, at the heat of hot water, with frequent agitation, yield a much more valuable product. They are nearly all employed as external applications only.

⁂ The following are the most important preparations of this class:——

=Oil of Adder’s Tongue.= _Syn._ OLEUM OPHIO GLOSSI, L. From the herb, as OIL OF BELLADONNA. A popular vulnerary.

=Oil of Ants.= _Syn._ OLEUM FORMICARUM. Digest 4 oz. of ants in 16 oz. (by weight) of olive oil with a gentle heat, and strain.

=Oil of Bal′sam Apple.= _Syn._ OLEUM BALSAMINÆ. _Prep._ Balsam apple (deprived of seeds), 1 oz.; oil of almonds, 4 oz.; digest and strain.

=Oil of Belladon′na.= _Syn._ OLEUM BELLADONNÆ (P. Cod.), L. _Prep._ From the fresh leaves, bruised, 1 part; olive oil, 4 parts; digested together at a gentle heat until the moisture is evaporated; the oil is then strained off with pressure, and filtered.

=Oil of Cantha′rides.= _Syn._ OLEUM CANTHARIDIS, O. CANTHARIDIBUS, L. _Prep._ (P. Cod. 1839). From Spanish flies (powdered), 1 part; olive oil, 8 parts; as OIL OF BELLADONNA. Stimulant and rubefacient. Used as a dressing to indolent sores, blisters, &c.; and in dropsy, rheumatism, gout, &c., OIL OF THE OIL-BEETLE (_Meloe proscarabæus_——Linn.) is prepared in a similar manner.

=Oil of Cap′sicum.= _Syn._ OLEUM CAPSICI, L. _Prep._ (Dr Turnbull.) From powdered capsicum or Cayenne pepper, 4 oz., olive oil, 1 pint; digested together for 6 hours, with heat, and strained. Stimulant; rubefacient in colic, cholera, &c.

=Oil of Cham′omile.= _Syn._ OLEUM ANTHEMIDIS, OL. CHAMÆMELI, L. From the dried flowers (rubbed to pieces), 1 part, olive oil, 8 parts; digested together, with heat, for 6 hours. Stimulant, emollient, and vermifuge.

=Oil of Col′ocynth.= _Syn._ OLEUM COLOCYNTHIDIS, L. From the pulp, as OIL OF CHAMOMILE. Diuretic. In dropsy, neuralgia, rheumatism, worms, &c.

=Oil of Earth′worms.= _Syn._ OLEUM LUMBRICORUM. (E. Ph. 1744.) Washed earthworms, 1/2 lb.; olive oil, 1-1/2 pint; white wine, 1/2 pint. Boil gently till the wine is consumed, and press and strain.

=Oil of Elder-flowers.= _Syn._ WHITE OIL OF ELDER; OLEUM SAMBUCI ALBUM, O. SAMBUCINUM (P. Cod.), L. _Prep._ From the flowers, as OIL OF CHAMOMILE. Emollient and discussive.

=Oil of Elder-leaves.= _Syn._ GREEN OIL, GREEN OIL OF ELDER, OIL OF SWALLOWS; OLEUM VIRIDE, O. SAMBUCI VIRIDE, L. _Prep._ 1. Green elder leaves, 1 lb.; olive oil, 1 quart; boil gently until the leaves are crisp, press out the oil, and again heat it till it turns green.

2. As before, but by maceration, at a heat under 212° Fahr. More odorous than the last.

3. Elder leaves, 1 cwt.; linseed oil, 3 cwt.; as No. 1.

_Obs._ The last form is the one usually employed on the large scale. It is generally coloured with verdigris, 1/2 lb. to the cwt., just before putting it into the casks, and whilst still warm; as, without great skill and a very large quantity of leaves, the deep-green colour so much admired by the ignorant cannot be given to it. The oil is got from the leaves by allowing them to drain in the pan or boiler (with a cock at the bottom), kept well heated. Emollient; in great repute among the vulgar as a liniment, in a variety of affections.

=Oil of Fen′ugreek.= _Syn._ OLEUM FŒNUGRÆCI, L. _Prep._ (P. Cod.) From the seeds, as OIL OF CANTHARIDES or of CHAMOMILE. Emollient and resolvent.

=Oil of Fox′glove.= _Syn._ OLEUM DIGITALIS, L. _Prep._ (P. Cod.) From the fresh leaves, as OIL OF BELLADONNA. Used as an application to chronic ulcers and indurations, painful swellings &c. As usually met with, it is nearly inert.

=Oil of Garden Night′shade.= _Syn._ OLEUM SOLANI, L. _Prep._ (P. Cod.) From the leaves, as OIL OF BELLADONNA. Anodyne and discussive.

=Oil of Gar′lic.= _Syn._ OLEUM ALLII INFUSUM, L. From garlic, as OIL OF BELLADONNA. Used as a liniment in deafness, diarrhœa, infantile convulsions, palsy, rheumatism, &c.

=Oil, Green.= _Syn._ OLEUM VIRIDI, L. From bay leaves, origanum, rue, sea wormwood, and elder leaves, of each 2-1/2 oz.; olive oil, 1 quart; as OIL OF ELDER. Detergent, stimulant, and resolvent. Green oil of elder is now usually sold for it.

=Oil of Hem′lock.= _Syn._ OLEUM CONII, L. _Prep._ (P. Cod.) As OIL OF BELLADONNA. Anodyne and emollient; in painful ulcers, glandular tumours, &c.

=Oil of Hen′bane.= _Syn._ OLEUM HYOSCYAMI, L. _Prep._ (P. Cod.) As OIL OF BELLADONNA. Used as the last, in various painful local affections.

=Oil Iodizeo, Marshall’s.= _Syn._ OLEUM IODATUM. _Prep._ Oil of almonds, 15 parts; iodine, 1 part. Triturate and digest till dissolved.

=Oil of Ju′′niper (by Infusion).= _Syn._ OLEUM JUNIPERI INFUSUM, L. From the crushed berries, as OIL OF BELLADONNA. Diuretic and vulnerary; in frictions, &c.

=Oil of Lil′ies.= _Syn._ OLEUM LILIORUM, L. From white lilies, 1 lb.; olive oil, 3 lbs.; as OIL OF BELLADONNA. Emollient; used to soften and ripen tumours, indurations, &c.

=Oil of Mel′ilot.= _Syn._ OLEUM MELILOTI, L. As the last, avoiding much heat. Emollient and resolvent.

=Oil of Mu′cilages.= _Syn._ OLEUM MUCILAGINUM, O. CUM MUCILAGINIBUS, L. _Prep._ 1. (Ph. L. 1746.) Marshmallow root, 1/2 lb.; linseed and fenugreek seed, of each, bruised, 3 oz.; water, 1 quart; boil 1 hour, add of olive oil, 2 quarts, and boil until the water is consumed.

2. Fenugreek seeds, 8 oz.; linseed oil, 1 quart; infuse a week, and strain. Once a highly popular emollient application in various local affections.

=Oil of Mu′dar.= _Syn._ OLEUM MUDARIS, L. From mudar bark (in coarse powder), 1 dr.; warm olive oil, 1/4 pint; digest 24 hours and strain. Used as an application to cutaneous ulcers, the bites of venomous animals, &c., and as a friction in worms.

=Oil of O′′pium.= _Syn._ ANODYNE OIL, OPIATED O.; OLEUM OPIATUM, L. _Prep._ From opium (in powder), 1 dr.; olive oil, 2-1/2 fl. oz.; digest at a gentle heat, with frequent agitation, for 5 or 6 hours. The powder should be rubbed in a mortar with a few drops of the oil before adding the remainder. As a local anodyne. The above is the only reliable formula for this preparation. Others are extant, but whilst the products of several are much stronger, those from others have only 1-5th or 1-6th the strength.

=Oils, Ozonised.= (Dr Thompson.) _Syn._ OLEO OZONATA. _Prep._ Pass oxygen gas into the oil (cocoa nut, sunflower, cod-liver oil, &c.) until it will dissolve no more. Then expose for a considerable time in the direct rays of the sun. Used in phthisis.

=Oil of Pel′litory.= _Syn._ OLEUM PYRETHRI, L. From bruised pellitory root, as OIL OF BELLADONNA. Used as the last.

=Oil of Black Pep′per (by Infusion).= _Syn._ OLEUM PIPERIS INFUSUM, L. From black pepper, in coarse powder, as OIL OF CAPSICUM. Stimulant and rubefacient; in frictions.

=Oil of Poison Oak.= _Syn._ OLEUM RHOIS TOXICODENDRI, L. From the leaves, as OIL OF BELLADONNA Externally; in paralysis, &c.

=Oil of Rhu′barb.= _Syn._ OLEUM RHEI, L. From rhubarb (in powder), 1 part; oil of almonds, 8 parts; digested together in a gentle heat for 4 hours, and strained, with expression. As an application to indolent ulcers, and as a friction over the abdomen in diarrhœa, English cholera, &c., or as a laxative when the stomach will not bear medicine.

=Oil of Ro′′ses.= _Syn._ OLEUM ROSÆ, O. ROSACEUM, O. R. INFUSUM, O. ROSATUM, L. _Prep._ From the fresh petals, pulled to pieces, crushed, and digested for 2 or 3 days in the sun, or a warm situation, in 4 times their weight of olive oil, and then pressed; the process being repeated with fresh roses. Ph. E. 1744 and P. Cod. are nearly similar. ALMOND, BEN, or OLIVE OIL, coloured with ALKANET, and scented with attar of roses, is now almost universally sold for it. Used for the hair.

=Oil of Rue.= _Syn._ OLEUM RUTÆ (INFUSUM), L. _Prep._ (P. Cod.) From fresh rue, bruised, as OIL OF CHAMOMILE. Reputed antispasmodic, emmenagogue, stimulant, and vermifuge. In frictions.

=Oil of St John’s Wort.= _Syn._ OLEUM HYPERICI (Ph. L. 1746), O. H. SIMPLEX, BALSAMUM H., L. From the flowers, 1 part; olive oil, 6 parts; digested together until the oil is well coloured. Antispasmodic, stimulant, and resolvent. A mixture of equal parts of RAPE OIL and GREEN ELDER OIL is usually sold for it.

=Oil of Scam′mony.= _Syn._ OLEUM SCAMMONII, O. PURGANS, L. _Prep._ (Van Mons.) From scammony (in powder), 1 dr.; hot oil of almonds, 3 fl. oz.; triturate together until cold, and the next day decant the clear portion.——_Dose_, 1/2 to 1 table-spoonful.

=Oil of Stramo′′nium.= _Syn._ OLEUM STRAMONII, L. _Prep._ (P. Cod.) From the leaves of thorn apple or stramonium, as OIL OF BELLADONNA. Anodyne and discussive; as an application to painful tumours, joints, &c.

=Oil of Tobac′co (by Infusion).= _Syn._ OLEUM TABACI, O. T. INFUSUM, L. From fresh tobacco leaves (bruised), like OIL OF CHAMOMILE. As an application in ringworm, irritable ulcers, pediculi, &c.; and as a friction in itch, neuralgia, painful indurations, &c. It must be used with extreme caution, as it is poisonous.

=Oil of Tooth′wort.= _Syn._ OLEUM SQUAMARIÆ, L. From the herb of _Lathræa squamaria_ (Linn.), as OIL OF ST JOHN’S WORT. Astringent and vulnerary. This must not be confounded with another preparation sometimes called ‘OIL OF TOOTHWORT’ (OLEUM PLUMBAGINIS EUROPÆÆ),and which has been occasionally used in itch, as the latter is acrid and apt to cause much irritation.

=Oil of Worm′wood.= _Syn._ OLEUM ABSINTHII, L. From the fresh herb, as OIL OF LILIES. The P. Cod. and Ph. Wurtem. order only part of the herb to 8 parts of oil. Applied to the abdomen in dyspepsia, diarrhœa, heartburn, worms, &c. It is seldom used in this country.

=OILS (Mineral).= _Syn._ HYDROCARBON OILS. An important class of liquids, consisting solely of carbon and hydrogen——the elements of ordinary coal-gas, and obtained by the distillation of coal, lignite, petroleum, and other bituminous substances. For the purposes of illumination, many of these oils are in most respects superior to the fixed or fat oils containing oxygen. They give a whiter and more brilliant light, and are produced at a much lower cost. The lamps in which they are burnt, when properly constructed, are less liable to get out of order than those adapted for the combustion of fat oils, and require less attention when in use. The experiments of Dr Frankland on the relative value of the ordinary illuminating agents[57] prove that the mineral oils are cheaper than all other portable illuminating agents in common use, and that they give, while burning, the largest amount of light with the least development of heat, and the smallest production of carbonic acid. With the oils adapted for burning in lamps other oils are produced. Some are very volatile and highly inflammable, and the safety of the burning oils depends on their proper extraction. These volatile liquids, when isolated, are used in the arts as substitutes for spirits of turpentine, as solvents for various substances, and to increase the illuminating power of coal-gas. Others are of a greasy nature, and are too heavy to be conveniently used in lamps. These, however, are well adapted for lubricating fine machinery, and are extensively employed instead of sperm oil by the cotton manufacturers of Lancashire. When the more volatile ingredients are separated from the burning oils, the latter are perfectly safe. Most of the mineral burning oils now in use are, we believe, free from danger in this respect. (See _Tests_, _below_.)

[Footnote 57: See article ILLUMINATION.]

_Hist._ For many years the manufacture of burning oils by the distillation of bituminous schists has been extensively carried out on the Continent, but the discovery which formed the foundation of the modern manufacture was made nearly thirty years ago by our countryman, Mr James Young. This gentleman took the lease of a spring of petroleum in 1847, and after numerous experiments succeeded in obtaining two useful oils from the crude liquid; the one being adapted for lubricating machinery, and the other for burning in lamps. The almost total cessation of the flow of petroleum terminated the business after two years’ working, and led Mr Young to institute a series of experiments to try if petroleum could be produced artificially by the destructive distillation of coal. These experiments resulted in the discovery of an oil which Mr Young named ‘Paraffin oil,’ as it had many of the chemical properties of the solid body of paraffin, discovered twenty years before by Reichenbach in beech-wood tar. Young’s patent (dated Oct. 7, 1850) involved the slower distillation of coals, at a lower temperature than had hitherto been employed for the purpose, and this novelty in practice was followed by the novel result of a copious production of liquid hydrocarbons. The gas or cannel coals were found to yield the liquids in largest quantities, that variety known as Boghead coal or Torbane Hill[58] mineral being specially adapted for the patented process. (See PARAFFIN OIL, _below_.) Soon after Young’s discovery native petroleum was brought from Rangoon, and purified by distillation, so as to produce oils very similar to the coal products. During the last few years, however, rich sources of petroleum have been discovered in North America, and from whence are imported the greater part of the vast quantities of petroleum oil (both for burning and lubricating purposes), together with the paraffin spirit, or naphtha, which are consumed in this country.

[Footnote 58: This species of coal is now exhausted.——ED.]

In the following table are given the quantities of these substances sent into England and Scotland during the year 1875:——

+---------+---------------+----------------+---------+-----------------+ | |Refined burning|Lubricating Oil.|Residuum.|Petroleum Spirit.| | | Oil. | | | | +---------+--------+------+----------------+---------+-------+---------+ | |Barrels.|Cases.|Barls. & Casks. |Barrels. |Cases. |Barrels. | |London | 169,762| 3,250| 2,511 | 1,000 | ... | 53,173 | |Liverpool| 95,853| 2,830| 300 | 29,358 | ... | 30,913 | |Hull | 20,226| 8| ... | ... | ... | ... | |Bristol | 36,889| 1,392| ... | ... | ... | 17,203 | |Clyde and| | | | | | | | Leith | 4,233| 4| 535 | 9,387 | ... | ... | +---------+--------+------+----------------+---------+-------+---------+ | Total | 326,963| 7,484| 3,346 | 39,745 | ... |101,289 | +---------+--------+------+----------------+---------+-------+---------+

This amounts to about 17 millions of gallons. In 1874 it exceeded 20 millions of gallons, but the stock in hand at the end of 1874 was about 5 millions of gallons, and the end of 1875 was only 1-1/2 million. The difference was mainly due to overtrading in 1874, which brought refined petroleum to the lowest price yet known in England, viz. 7-3/4d. per gallon in December, 1874, and checked its subsequent importation.[59]

[Footnote 59: W. Matthieu Williams.]

_Tests, Precautions._ The Sanitary Commission of the ‘Lancet’ took as the limit of safety an oil that gave off inflammable vapour when heated to 130° Fahr., and this has been generally accepted by dealers. If an oil gives off inflammable vapours before being heated up to 130°, it is considered unsafe for domestic use.

1. The plan for testing this, recommended in the ‘Lancet,’ is to heat a portion of the suspected oil in a gallipot placed in boiling water, ascertaining by a thermometer suspended in the oil the temperature at which it will take fire on the surface when a lighted wax vesta is applied to it. This is a troublesome and dangerous process, and has little practical value.

2. A rough-and-ready method of testing the inflammability of a sample is to pour a little out on a dry flat board, and try whether it can be ignited readily by a lighted paper. If it catches fire like turpentine or brandy, the oil is dangerous.

3. The following plan, proposed by Mr Tegetmeier, requires no scientific knowledge and no apparatus but what is to be found in every house, while it is sufficiently accurate for all practical purposes:——

“Take an earthenware dish, holding about half a pint (a breakfast cup will do), fill the cup full from a kettle of boiling water, pour this into an earthenware quart jug, then fill the same cup again with boiling water from the kettle, and pour it also into the quart jug, then fill the cup with cold water, put it into the jug, shake the jug to mix the hot and cold water, then pour the tepid water from the jug into the cup till the cup is half full, then pour about a table-spoonful of the oil to be tested on the tepid water in the cup, take the oil-can with the oil out of the room, then touch the surface of the oil in the cup with a lighted splinter of wood, or a match without sulphur. If the match causes a flash of flame to appear on the surface of the oil, the oil is below the standard of safety, and should not be used; if no flame appears, the oil is up to the standard. We may mention that in this trial no time should be lost after pouring the boiling water from the kettle, as the water may get too cold, but the whole may be gone through in from two to three minutes. It is well to have a saucer at hand, and if the oil should be a bad oil, and ignite with the match, place the saucer on the mouth of the cup, and the flame is extinguished. This trial should be done by daylight, and at a distance from a fire, and the directions must be followed exactly in the order as given above.”

4. Provided that the oils to be examined have been produced by careful fractional distillation, their relative volatility, as indicated by their specific gravity, shows to a great extent the facility with which they ignite. The lightest oils are more volatile and more easily inflamed than those which are heavier. Oils much under ·800 inflame directly a lighted match is thrown into them, whereas oils at about ·815 to ·823 (if unmixed products) cannot be set on fire in this manner. The specific gravity test cannot, however, be depended on to determine the inflaming point of any commercial oil. A heavy oil, badly rectified, may contain a proportion of very volatile vapour, and have a low inflaming point; whereas a much lighter oil may be perfectly safe, from its having the more volatile portions carefully removed.

5. (Van der Weyde.) The oil to be tested is placed in a graduated tube closed at one end; the open end is then closed with the finger, and is then placed mouth downwards in a vessel of water that is heated from 43°——44° C. The vapour from the portion volatilised at this temperature then collects in the upper part of this tube, and expels a corresponding quantity of oil. See PETROLEUM.

In Great Britain petroleum is defined by Act of Parliament as being any oil which gives off all inflammable vapour at a temperature less than 100° F.

To prevent accidents with paraffin or petroleum lamps, the following precautions ought to be observed:——

The lamps should be filled and trimmed by daylight.

They should never be overfilled; the oil should not be allowed to come into contact with the metal work of the burner.

Any portion of oil spilled on the outside of the lamp should be carefully wiped away.

When not in use the wick should be turned down into the wick-holder.

⁂ The principal products noticed below rank high among the numerous varieties of mineral oil now in the market, but there are doubtless many others equally good and safe. Their properties are described in accordance with the results obtained by Mr W. B. Tegetmeier, who has devoted much time to the examination of the mineral oils:——

=Oil, Al′bertite.= From ‘Albertite,’ a lustrous black mineral found in New Brunswick. A sample was shown in the Colonial Department of the International Exhibition of 1862, but the oil has not yet appeared in the English market.

_Prop._ Odour very slight; illuminating power high; boiling point 338° Fahr., or 126° above that of water.

=Oil, American.= See PETROLEUM OIL (_below_).

=Oil, Apyroec′tic.= _Syn._ NON-EXPLOSIVE OIL. A burning oil, introduced by F. Tall, of Hull, and prepared, we believe, from American petroleum.

_Prop._ Slightly coloured; perfectly limpid; odour slight, but not perceivable during combustion. The most remarkable property of this oil is that, in spite of its limpidity, the point at which it gives off inflammable vapour is 180° Fahr., or 80° above the requirements of the Petroleum Act.

=Oil, Bel′montine.= From Rangoon tar, or Burmese petroleum, by distillation; superheated steam being employed as the heating agent.

_Prop._ Colourless; odour not unpleasant; sp. gr. ·847; but although so heavy, the oil is altogether free from viscosity, and will rise rapidly in a comparatively long wick; inflaming point 134° Fahr.; burns with an exceedingly white light, and possesses a very high illuminating power.

_Obs._ The distillation of the Rangoon tar is carried on by Price’s Patent Candle Company under a patent. Besides the above lamp oil, several beautiful and useful products are obtained. At first there comes over a very volatile liquid, termed SHERWOOD OIL, used as a detergent for removing grease from fabrics, cleaning gloves, &c.; then comes the BELMONTINE OIL, already noticed; then two lubricating oils, the one light and the other heavy; and, last of all, when the temperature is considerably elevated, the beautiful white, translucent solid known as BELMONTINE, distils over. This last is a kind of paraffin, and is used for making ornamental candles.

=Oil, Caz′eline.= An excellent burning oil, probably prepared from American petroleum, introduced by Cassell, Smith, and Co., of London.

_Prop._ Bright, limpid, with scarcely a trace of colour; odour very slight, and quite free from any objectionable character; sp. gr. ·805; lowest point of ignition 144° Fahr.; burns with a pure white light, free from smoke and smell.

=Oil, Col′zarine.= A heavy hydrocarbon oil, adapted for burning in lamps constructed from the old ‘Moderators’ and ‘Carcels,’ formerly so much used for the fat oils.

_Prop._ Limpid; quite inodorous; of a pale amber colour; sp. gr. about ·838; temperature at which the vapour can be permanently ignited, 250° Fahr. Tested in the altered moderator, it gives an intense white light, without smoke or smell. Compared with vegetable colza oil, its illuminating power is in the proportion of 3 to 2.

_Obs._ This oil is manufactured by Cassell, Smith, and Co., under Martin’s patent for the modification of mineral oils, to fit them for burning in lamps where ‘colza’ and other vegetable and animal oils have been usually consumed. Similar oils are prepared by other firms.

=Oil, Machin′ery.= _Syn._ LUBRICATING OIL, SHAFTING O., SPINDLE O. The heavier hydrocarbon, oils obtained in distilling coal, shale, and petroleum, have almost superseded the fat oils for lubricating purposes. They have no chemical action on the ordinary metals, and are not affected by cold. The lightest of these comparatively heavy oils are used for spindles, or other kinds of rapid machinery; the heaviest for the bearing parts of heavy machinery; and those of an intermediate character for such things as printing-presses, agricultural steam-engines, &c. In America and on the Continent this oil is also used for making gas. The firm of Whitmore and Craddock is favorably known for the manufacture and purification of these machinery oils. See OIL, BELMONTINE (_above_), and OIL, PARAFFIN (_below_).

=Oil, Pa′raffin.= _Syn._ PARAFFINE OIL. This name was given by Mr Young to the oil produced by the distillation of cannel coal, Boghead coal, &c., at a temperature considerably lower than that employed in the manufacture of illuminating gas. The following is a brief outline of Mr Young’s process:——

_Manuf._ (Young’s patent.) Boghead coal, broken into small fragments, is introduced into perpendicular tubes or retorts, about eleven feet in height, by conical hoppers at their upper extremities. Four of these tubes constitute a set, being built into one furnace, and charged by a single workman. They pass completely through the furnace, and are closed below by dipping into shallow pools of water, while the openings into the hoppers above may be shut by spherical valves. The coal in each tube is gradually heated as it descends to that part which passes through the furnace, and when it reaches the bottom of the tube it has parted with its volatile constituents, and is raked away as refuse, the coal from above descending as it is removed. Thus, the action of these perpendicular retorts is continuous, and the distillation goes on uninterruptedly both day and night. The vapours produced are conducted by iron tubes to the main condensers, which consist of a series of syphon pipes freely exposed to the air. The quantity of incondensible gas formed is inconsiderable; and it is this result, so different from that obtained in the ordinary gasworks, that marks the great value of Young’s process. The crude oil, a dark-coloured, thick liquid, is then distilled to dryness in large iron cylindrical stills, and is thus freed from the excess of carbon which is left behind as coke. The oil, after distillation, is further purified by being acted upon by strong sulphuric acid (oil of vitriol), which chars the principal impurities, and causes them to subside in the form of a dense black, heavy acid tar. To separate the remaining impurities, and that portion of the sulphuric acid which remains in the oil, it is next subjected to the action of caustic soda. As thus purified, the paraffin oil contains four distinct commercial products. To effect their separation, the process of fractional distillation is first employed. The first elevation of temperature drives over the lighter and more volatile portions, which, when purified by a subsequent distillation, yields the fluid known as ‘paraffin naphtha,’ ‘petroleum spirit,’ ‘benzoline.’ This product is used as a substitute for ‘turps,’ as a solvent for india rubber for cleaning gloves, and for burning in those naphtha lamps so much employed by costermongers, and workmen in railway tunnels and similar situations. On the perfect separation of this naphtha the safety of the burning oil depends. This burning oil, the ‘paraffin oil’ of commerce, comes over at a much higher temperature than the naphtha. It is a perfectly safe lamp oil, and has a greater illuminating value than any other oil in the market. Its properties are noticed _below_. The third product in point of volatility is a comparatively heavy liquid (machinery oil), largely used for lubricating purposes in the Lancashire factories. From this oil, and others which come over at a very high temperature, the fourth commercial product is separated by the action of artificial cold. This last product is the beautiful translucent solid, paraffin, now much used as a candle material.[60] (See OIL, PARAFFIN, PETROLEUM.)

[Footnote 60: For a detailed account of the processes carried on at the Bathgate works, see Mr Tegetmeier’s paper in ‘England’s Workshops,’——Groombridge and Sons.]

In the preparation of paraffin oil, from native petroleum, the oil is obtained by direct distillation from the petroleum, and subsequently separated from the more or less volatile hydrocarbons (the paraffin naphtha, the lubricating oils and the solid paraffin) that are associated with it by fractional distillation as in Young’s process; whereas, when procured from bituminous minerals, it is derived from the _tar_ or _crude oil_, which has to be previously extracted from the bituminous matters by destructive distillation. There are various methods for obtaining this tar or crude oil, which, although differing in detail, are in general principles very similar to that described in Young’s patent. Thus, whilst in many works _closed_ horizontal retorts are employed, in other establishments vertical ones, to the bottoms of which are attached receptacles for the receipt of the exhausted coal or other material as it falls from the retort, the same as in Young’s apparatus, are extensively adopted. When horizontal retorts are employed they are made of cast iron, and vary in length from 8 to 10 feet, being from 28 to 34 inches wide and from 9 to 14 inches deep. The charge is introduced by an opening in the end of the retort, by which aperture the exhausted residue is removed when necessary. This aperture is closed by a tightly fitting cast iron cover while the distillation is going on. At the other end of the retort is a pipe for carrying off the products of distillation. This communicates with a larger pipe, and this latter with the condensing apparatus. A number of these retorts are set together in a row, with a furnace at one end, and flues extending beneath the retorts, while the upper parts of the retorts are covered with brickwork, to prevent the oil vapours from being decomposed by the heat of the waste furnace gas passing to the chimney through the flues above the retorts.

The gaseous products of the distillation of the tar, leaving the retort by the exit tube already described, are cooled by being made to pass through a number of iron pipes exposed to the air, or surrounded by water, and thus becoming condensed pass into a reservoir in the form of the oil, which forms the material from which the various hydrocarbons are separated by fractional distillation. Accompanying the oil vapours are certain uncondensable gases; these escape through a properly contrived outlet which is made in the condensing pipes; in some works these escaping gases are utilised as fuel, and in others for purposes of illumination.

In other works superheated steam is driven into the retorts during the process of distillation; but although this has the effect of sweeping the oil vapour more quickly out of the retort into the condenser, it is questionable whether this advantage covers the extra cost of the production of the steam.[61]

[Footnote 61: Payne’s ‘Industrial Chemistry.’ Edited by Dr Paul.]

In many parts of Germany the extraction of the crude oil or tar from bituminous substances is effected in ovens. In these ovens the bituminous body is thrown upon a layer of burning fuel which covers the bottom of the oven, the result being that the bituminous matter is resolved into gaseous bodies which are lost, and tar which flows downwards toward the burning fuel, which being covered with a layer of clay is prevented from entering into violent combustion. This method, however, is only had recourse to on a small scale, since it is found that in most cases the tar obtained by means of it is not of a kind suited for yielding paraffin and paraffin oils.

The preparation of the tar or crude oil from fossil fuel, of the character already specified, constitutes one of the most delicate and difficult branches in the manufacture of paraffin oils, and paraffin, &c. The chief sources of failure to be avoided are the overheating of the oil vapour, and its consequent decomposition (varying in amount) into useless gaseous products; and its inefficient condensation.

It has been shown by Vohl that even when the construction of the retorts is not of the best, an average yield of tar may be obtained by the proper condensation of the vapours. “The complete condensation of the vapours of the tar is one of the most difficult problems the mineral oil and paraffin manufacturer has to deal with, while the means usually adopted for condensation, such as large condensing surfaces, injection of cold water, and the like, have proved ineffectual. It has often been attempted to condense the vapours of tar in the same manner as those of alcohol, but there exist essential differences between the distillation of fluids and dry distillation. In the former case the vapours soon expel all the air completely from the still and from the condenser, and provided, therefore, that, in reference to the size of the still and bulk of the boiling liquid, the latter be large and cool enough, every part of the vapour must come into contact with the condensing surfaces. In the process of dry distillation the process is entirely different, because with the vapours, say of tar, permanent gases are always generated. On coming into contact with the condensing surfaces a portion of the vapours is liquefied, leaving a layer of gas as a coating, as it were, on the condensing surface. The gas being a bad conductor of heat prevents to such an extent the further action of the condensing apparatus, that a large proportion of the vapours are carried on, and may be altogether lost. A sufficient condensation of the vapours of tar can be obtained only by bringing all the particles of matter which are carried off from the retorts into contact with the condensing surface, which need neither be very large nor exceedingly cold, because the latent heat of the vapours of tar is small, and consequently a moderately low temperature will be sufficient to condense those vapours to the liquid state. The mixture of gases and vapours maybe compared to an emulsion such as milk, and as the particles of butter may be separated from milk by churning, so the separation of the vapours of tar from the gases can be greatly assisted by the use of exhausters acting in the manner of blowing fans. It is of the utmost importance in condensing the vapours of tar that the molecules of the vapours be kept in continuous motion, and thus made to touch the sides of the condenser. The condenser should not be constructed so that the vapours and gases can flow uninterruptedly in one and the same direction.”[62]

[Footnote 62: B. Wagner.]

An important condition for the safe and quiet distillation of the tar or crude oil when obtained is that it should be free from water. Unless the removal of the water is effectually accomplished, during its distillation, the tar may boil over, and coming into contact with the fire under the still may give rise to an alarming conflagration. The dehydration of the tar is effected in an apparatus constructed for the purpose, consisting of an iron tank placed within a larger tank, a space of about two inches intervening between the two tanks is filled with water, which is heated to, and kept at a temperature of between 60° and 80° C., for 10 hours, by the end of which time the ammoniacal water having separated from the lighter tar is drawn off by a stop-cock placed at the bottom of the tank, whilst the tar is decanted through a valve at the top.

In America the distillation of the natural petroleum oils is carried out in cylindrical stills capable of holding as much as 1600 gallons each. The retorts employed in the distillation of the tar or crude oils obtained from shale and other bituminous compounds are often constructed of large cast-iron flanged pans, each capable of containing from 1-1/2 to 3 tons of the oil, “and forming the body of the retort. The pan is set in brickwork with flues running round the upper portion, and beneath it is a perforated dome of brickwork, through which the flame and hot gas from the furnace pass up round the bottom of the pan before entering the flues by which the upper portion of the pan is heated. To the flange of the pan is fitted a flanged cover having on one side a discharge pipe through which the vapour is passed to the worm of the condenser. In the centre of the cover is a manhole. The oil condensed in the worm is discharged through a pipe into a receiver, and the uncondensable gas escapes through an ascending pipe.”[63]

[Footnote 63: Palen.]

The processes to which the crude oil or tar and the natural petroleum are next submitted differ only in the degree of treatment with certain agents to which these products are subjected when, after similar methods of fractional distillation, they have been isolated from each other. The benzoline and paraffin oils (both for burning and lubricating purposes) separately yielded by the natural oils seldom require purification, or if so in a minor degree only, whilst the same bodies as obtained from the crude shale oil or tar must be submitted to various processes of depuration before they are fit for the market. Thus, the crude petroleum or burning oil derived from tar is characterised by a more or less dark colour and disagreeable smell——properties which are partly due to the presence of carbolic acid and its homologues. By agitating the paraffin oil with a solution of caustic soda these objectionable substances are removed.

The oil, being next separated from the alkali by subsidence, and any remains of the soda being removed from it by washing with water, is next mixed with an aqueous solution of sulphuric acid in the proportion of 5 per cent. of acid of sp. gr. 1·70. The acid removes from the oil certain basic substances derived from the tar, which, like the carbolic acid, give to it a bad odour and a dark colour. In this operation thorough admixture of the acid with the oil is important, and this is generally effected by mixing the two in vessels furnished with puddles. After a time, and when the mixture has separated into two layers, the upper one or the paraffin oil is drawn off from the lower or acid one, and well washed with water; in some instances lime water is used for the washing, in others the water is impregnated with caustic alkali. With some samples of crude paraffin oil the above operations have to be repeated two or three times, and even redistilled before the oil becomes sufficiently pure and colourless for sale. When redistilled, the last portions which come over are often found to yield some solid paraffin in addition to that furnished by the first fractional distillation. The ‘paraffin,’ ‘naphtha,’ ‘petroleum,’ ‘spirit,’ or ‘benzoline’ (by all of which names it is known), which forms the more volatile portion of the tar, and which is the first to pass over from the retort, is subjected to the same treatment as that used for burning oil; as for the denser lubricating oil, which passes over after the burning portion, this being freed from any of the latter, is set aside in a cool place, in order that any solid paraffin it contains may crystallise out, and be separated from it.

The waste carbolate of soda resulting from the treatment of the oil with the caustic alkali, being decomposed by sulphuric acid, the liberated carbolic acid is utilised either as a disinfectant, or for saturating railway sleepers; and sometimes as a source of certain tar colours; or it may be used in the manufacture of gas, the soda which remains in the coke being extracted by lixiviation. The waste sulphuric acid combined with the ammoniacal liquors that always accompany the first stages of the distillation of the tar is made into sulphate of ammonia.

_Prop._ The paraffin oil of commerce is of a very pale amber colour; is bright, perfectly transparent, and remarkably limpid. Its sp. gr. is ·823. Its point of temporary ignition is 150° Fahr., that of permanent ignition being a few degrees higher. Its odour is very slight. Its rate of combustion is slow, as may be inferred from the absence of the lighter oils, as indicated by its high sp. gr. and inflaming point. At the same time its limpidity proves the absence of the heavier oils, and accounts for its rising through a long wick with freedom, and burning without charring the cotton.

=Oil, Petro′leum.= _Syn._ KEROSENE OIL, REFINED PETROLEUM, PARAFFIN OIL. Most of the burning oils now in the market are derived from American petroleum. That obtained from natural petroleum is now manufactured solely in America. The native petroleums vary greatly in properties, and numerous methods of refining are employed by the manufacturers. The Canadian petroleum contains sulphuretted hydrogen, which imparts to it a very disagreeable smell, and is difficult of removal. Some make use of both acids and alkalies, others employ alkalies alone, and steam is applied at various degrees of heat. Some of the oils produced are of excellent quality, but others are inferior, and do not ascend the wick in sufficient quantity to afford a constant light. None of the native petroleums contain carbolic acid and other impurities which exist in the oils distilled from coals and shales; hence their purification is simple and comparatively cheap. “The oil prepared from petroleum is almost colourless; it has a specific gravity of about ·810, and when of good quality only a slight and rather aromatic odour.” (Payen.) See PETROLEUM, and _above_.

=Oil, Shale.= As we have stated, products analogous to those derived from cannel coal are obtained by the destructive distillation of bituminous shales and schists, and lignites or brown coals. On the Continent the production of shale oils has of late years declined considerably, owing to their unsuccessful competition, in point of price, with the American petroleum oils. The oil obtained from bituminous shale or from coal is generally of higher specific gravity than that procured from petroleum; it is deeper in colour, and not so pleasant in smell.

=OILS (Mixed).= _Syn._ COMPOUND OILS; OLEA COMPOSITA, OLEA MIXTA, L. Under these names are commonly included various mixtures of oils and other substances that possess an unctuous appearance. When not otherwise stated, they are prepared by simply agitating the ingredients together, and, after a sufficient time, decanting the clear portion, which, in some cases, is then filtered. A few of them only possess any importance. Some of them are highly esteemed as remedies among the vulgar, and the use of others is confined to veterinary medicine.

The following include the principal mixed oils of the shops, to which the names of a few other compounds, which are frequently called ‘_oils_’ by the ignorant, are added, for the purpose of facilitating a reference to them:——

=Oil of Turpentine, Sulphurated.= _Syn._ OLEUM TEREBINTHINÆ SULPHURATUM. _Prep._ Sulphurated linseed oil, 1 part; oil of turpentine, 3 parts.

=Oil of Turpentine (for acoustic use).= _Syn._ OLEUM TEREBINTHINÆ ACOUSTICUM. (Mr Manle.) Oil of almonds, 4 drams; oil of turpentine, 40 minims.

=Oil, Acou′stic.= _Syn._ EAR OIL; OLEUM ACOUSTICUM, O. TEREBINTHINÆ ACOUSTICUM, L. _Prep._ From oil of turpentine, 1 part; oil of almonds, 6 parts; mix. In atonic deafness, accompanied with induration of the wax. 1 or 2 drops are poured into the ear, or on a piece of cotton wool, which is then gently placed in it.

=Oil, Black.= _Syn._ OLEUM NIGRUM, L. _Prep._ 1. Oil of turpentine, 1 pint; rape oil, 3 pints; oil of vitriol, 1/4 lb.; agitate well together with care; then add of Barbadoes tar, 3 oz.; again agitate well, and in 10 days decant the clear portion. Linseed oil is preferred for the above by many persons.

2. (Percivall.) Sweet oil, 1 pint; oil of turpentine, 2 oz.; mix, add gradually of oil of vitriol; 1-1/4 oz.; again mix, and leave the bottle open until the next day. Detersive, stimulant. Used by farriers for mange, &c.

=Oil, British.= _Syn._ COMMON OIL OF PETRE; OLEUM BRITANNICUM, O. PETRÆ VULGARE, L. _Prep._ From oil of turpentine, 1 quart; Barbadoes tar, 1 lb.; oils of rosemary and origanum, of each 1 oz. Stimulant. Formerly reputed to possess the most astonishing virtues.

=Oil, Camphora′ted.= Liniment of camphor.

=Oil, Car′ron.= Liniment of lime.

=Oil, Chabert’s.= _Syn._ CHABERT’S EMPYREUMATIC OIL; OLEUM CHABERTI, O. CONTRA TÆNIAM CHABERTI, L. Oil of turpentine, 3 parts; Dippel’s animal oil, 1 part; mix, and distil 3 parts. It must be preserved from the air and light. Used in tapeworm.——_Dose_, 1 to 2 teaspoonfuls, in water, night and morning, until 5 or 6 fl. oz., or more, have been taken; a cathartic being given every third day.

=Oil, Exeter.= _Syn._ OLEUM EXCESTRENSE. (Gray.) Green oil, 16 lbs.; euphorbium, mustard seed, castor, pellitory, of each 1 oz.; digest and strain. The original form is more complex. The following is also used:——Rape oil, 1-1/2 pint; green oil, 1/2 pint; oils of wormwood, rosemary, and origanum, of each half a dram.

=Oil, Fur′niture.= _Syn._ MAHOGANY OIL, OIL STAIN. _Prep._ 1. From refined linseed oil, 1 pint; alkanet root, 1/4 oz.; digested together in a warm place until the former is sufficiently coloured, when it is poured off and strained.

2. Pale boiled oil, 1 pint; beeswax, 1/4 lb.; melted together, and coloured as before. Gives a superior polish, which becomes very tough by age.

3. Linseed or boiled oil, 1 pint; Venice turpentine (pure), 6 oz.; as before. The above are used for mahogany and other dark-coloured woods.

4. Linseed oil, 8 oz.; vinegar, 4 oz.; oil of turpentine, mucilage, rectified spirit, of each 1/2 oz.; butter of antimony, 1/4 oz.; hydrochloric acid, 1 oz. Mix.

5. Linseed oil, 16 oz.; black resin, 4 oz.; vinegar, 4 oz.; rectified spirit, 3 oz.; butter of antimony, 1 oz.; spirit of salts, 2 oz.; melt the resin, add the oil, take it off the fire, and stir in the vinegar; let it boil for a few minutes, stirring it; when cool put it into a bottle, and add the other ingredients, shaking all together. The last two are specially used for reviving French polish.

6. (Pale.)——_a._ As the preceding, omitting the alkanet.

_b._ From nut oil, 3/4 pint; beeswax (finest), 3 oz.; melted together.

_c._ To the last add of copal varnish, 3 or 4 oz.

The last three are employed for pale woods. They are all applied by means of a rag, and are ‘polished off’ with a ‘woollen rubber’ or ‘furniture brush.’ A little strong vinegar, or a few drops of hydrochloric acid, are sometimes added. See POLISH.

=Oil, Hair.= See OIL (Perfumed).

=Oil and Hartshorn.= Liniment of ammonia.

=Oil, I′ron.= _Syn._ OLEUM FERRI, O. MARTIS, L. The old name for the liquid formed when perchloride of iron is allowed to deliquesce by free exposure to the air. It is excessively caustic and corrosive.

=Oil, Lime.= See CALCIUM (Chloride).

=Oil, Macas′sar.= See OILS (Perfumed).

=Oil, Mar′row.= _Prep._ From clarified beef marrow, 1 part; oil of almonds, 3 parts; melted together, and strained through muslin. It is usually scented with ambergris, cassia, or mace, and slightly tinged with palm oil or annotta. Used for the hair.

=Oils, Marshall’s.= _Prep._ From linseed oil and rape oil, of each 1 lb.; green oil and oil of turpentine, of each 1/2 lb.; oil of origanum, 1/2 fl. oz.; oil of vitriol, 1/4 oz.; well shaken together.

=Oils, Mixed.= _Syn._ OLEUM MIXTUM COMMUNE, L. _Prep._ From linseed oil and green oil, of each 1 lb.; oil of turpentine, 1/2 lb.; Barbadoes tar and balsam of sulphur, of each 2 oz.; oils of spike and origanum, of each 1 oz. Stimulant and rubefacient. Used by farriers for sprains, &c. See OILS, STAMFORD’S (_below_).

=Oils, Newmarket.= _Prep._ From oils of linseed, turpentine, and St John’s wort, of each 3 lbs.; oil of vitriol, 1-1/2 oz.; well shaken together, and the clear portion decanted in a few days. A favourite remedy for sprains in horses.

=Oils, Nine.= _Syn._ OLD MIXED OILS; OLEUM EX OMNIBUS, L. _Prep._ From train oil, 1 gall.; oil of turpentine, 1 quart; oil of amber and oil of bricks, of each 5 oz.; oil of spike and oil of origanum, of each 2 oz.; Barbadoes tar, 2-1/2 lbs.; oil of vitriol, 2 oz.; camphorated spirit, 1/2 pint, mixed together as the last. A favourite remedy with provincial farriers.

=Oil of Petre.= See OIL, BRITISH (_above_).

=Oil, Phos′phorated.= _Syn._ OLEUM PHOSPHORATUM, L. _Prep._ 1. (Ph. Bor.) Phosphorus (dried and sliced small), 6 gr.; oil of almonds, 1 oz.; mix, place the phial in hot water, agitate for some time, and, when cold, decant the clear oil from the undissolved phosphorus.

2. (Magendie.) Phosphorus (sliced), 1/2 dr.; almond oil, 1 oz.; macerate in the dark, with frequent agitation, for 14 days, then, after repose, decant the clear portion, and aromatise it with a little essence of bergamotte.

3. (B. Ph.) _Prep._ Take of phosphorus and oil of almonds, of each q. s. Heat the oil in a porcelain dish to 300° F., and keep it at this temperature for about 15 minutes, then let it cool and filter it through paper. Put 4 fluid ounces of this oil into a stoppered bottle capable of holding four and a half fluid ounces; then add to it 12 grains of phosphorus. Immerse the bottle in hot water until the oil has acquired the temperature of 180° F., removing the stopper two or three times to allow the escape of expanded air, then shake the oil and phosphorus together, until the latter is entirely dissolved.——_Dose_, 5 to 10 minims.

_Obs._ A fl. oz. of oil dissolves rather less than 5 gr. of pure phosphorus. The large excess ordered in the second formula must be merely for the purpose of increasing the extent of surface acted on. It is, however, with the other precautions given, quite unnecessary. The products of both formulæ have the same strength.——_Dose_, 5 to 10 or 12 drops, in milk, barley water, or gruel, or made into an emulsion; in chronic rheumatism, gout, &c., and as a powerful, diffusible stimulant in various diseases with debility and general prostration of the vital powers, &c. Externally, as a friction. It is chiefly to the presence of phosphorus that cod-liver owes its wonderful remedial power in these affections.

=Oil, Quit′ter.= _Prep._ 1. Red precipitate, 2 dr.; aquafortis, 1 oz.; dissolve, add of olive oil, oil of turpentine, and rectified spirit, of each 2 oz.; and agitate well and frequently for 3 or 4 hours.

2. Ointment of nitrate of mercury (Ph. L.), 1 part; nut oil, 3 parts; melt together, and stir until the mixture is cold. Used by farriers for quitters, &c.

=Oils, Radley’s.= From Barbadoes tar, 1/2 lb.; linseed oil and oil of turpentine, of each 1/4 pint; gently warmed, and shaken together.

=Oil, Shav′ing.= See ESSENCE OF SOAP.

=Oil, Sheldrake’s.= _Prep._ From pale boiled nut oil and copal varnish, equal parts, melted together by the heat of hot water, and, when perfectly mixed, placed aside in a bottle for a week to settle, after which the clear portion is decanted. Used by artists to grind their colours in to brighten them.

=Oil of Spike.= 1. (FARRIER’S). From oil of turpentine, 1 quart; Barbadoes tar, 1-1/2 oz.; alkanet root, 1/2 oz.; digested together for a week. Used as a stimulating liniment by farriers.

2. (PAINTER’S.)——_a._ From rectified oil of turpentine, 3 pints; oil of lavender, 1 pint; mix.

_b._ Oil of turpentine (warm), 5 parts; lavender oil bottoms (genuine), 3 parts; agitate well together, and in a fortnight decant the clear away. Used by artists and enamellers.

=Oils, Stamford’s.= _Syn._ LORD STAMFORD’S MIXED OILS. _Prep._ Dissolve camphor, 1 oz., in rectified spirit of wine, 1/4 pint; add oil of origanum, 2 oz.; oil of turpentine, 1/2 pint; green elder oil, 2 lbs.; and agitate until mixed. The rectified spirit is now generally omitted, the camphor being dissolved in the green oil by aid of heat before adding the other ingredients. Stimulant. Used by farriers.

=Oil, Sul′phurated.= _Syn._ BALSAM OF SULPHUR; OLEUM SULPHURATUM, BALSAMUM SULPHURIS, L. _Prep._ 1. (Ph. L. 1746.) Flowers of sulphur, 1 part; olive oil, 4 parts; boil together in a vessel lightly covered, until they assume the consistence of a thick balsam.

2. (Ph. L. 1824.) Olive oil, 16 fl. oz.; heat it in a sand bath, and gradually add of washed sulphur, 2 oz.; stirring until they combine.

_Prop., &c._ Balsam of sulphur is a dark, reddish-brown, viscid fluid, having an extremely disagreeable and penetrating odour, and a strong, nauseous taste. The local action of balsam of sulphur is that of an acrid and irritant; its remote effects those of a stimulant, expectorant, and diaphoretic. Externally, it is occasionally used as an application to foul ulcers; and was formerly commonly employed internally in chronic pulmonary affections, in doses of 20 to 50 drops. It is now seldom given internally except in veterinary practice.

=Oils, Three.= _Syn._ OLEUM DE TRIBUS (Van Mons), L. Oils of brick, lavender, and turpentine, equal parts. As a stimulant liniment.

=Oil of Vit′riol.= Sulphuric acid.

=Oils, Ward’s.= _Syn._ WARD’S WHITE OILS. From powdered camphor, rape oil, oil of turpentine, rectified spirit, and liquor of potassa, equal parts, agitated together for some time, and again before use. Beef brine was formerly used instead of liquor of potassa.

=Oil, Watchmaker’s.= Prepared by placing a clean strip or coil of lead in a small white-glass bottle filled with pure almond or olive oil, and exposing it to the sun’s rays at a window for some time till a curdy matter ceases to be deposited, and the oil has become quite limpid and colourless. Used for fine work; does not become thick by age.

=Oil, Wedell’s.= _Syn._ BEZOAR OIL; OLEUM BEZOARDICUM, L. From nut oil, 1/4 pint; camphor, 1/2 oz.; dissolve by a gentle heat, and, when cold, add of essence of bergamot, 1 dr., and let it stand over a little alkanet root until sufficiently coloured.

=Oils, White.= _Syn._ WHITE EGG-OILS. _Prep._ 1. Yolks of eggs, 4 in number; oil of turpentine, 1/4 pint; mix, add of liquor of ammonia, 3 fl. oz.; oil of origanum, 1/2 oz.; soaper’s lye, 1/4 pint; water, 3/4 pint; agitate well, and strain through a coarse hair sieve.

2. Rape oil, 3/4 pint; liquor of ammonia and oil of turpentine, of each 3 oz.; agitate until they form a milk.

3. (Redwood.) Whites and yolks of 2 eggs; oil of turpentine, 1-1/2 oz.; triturate together, add of Goulard’s extract, 1/2 oz; mix, next add of distilled vinegar, 1-1/2 pint, and, lastly, of rectified spirit, 1-1/2 fl. oz. Stimulant and detergent. Used by farriers.

=Oil, Worm (Canine).= _Syn._ OLEUM VERMIFUGUM CANINUM. _Prep._ From oil of turpentine and castor oil, equal parts; tinged yellow with a little palm oil or annotta.——_Dose._ For a middle-sized dog, 1/2 oz., repeated in 2 or 3 hours if it does not operate.

=OILS (in Perfumery).= _Syn._ SCENTED OILS; OLEA FIXA ODORATA, L. The oils which usually form the basis of these articles are those of almonds, ben, or olives; but others are occasionally used. The methods adopted for their preparation vary with the nature of the substances whose fragrance it is intended to convey to the oil. The Continental perfumers employ three different processes for this purpose, which they technically distinguish by terms indicative of their nature. These are as under:——

1. A sufficient quantity of the essential oil of the plant, or of the concentrated essence of the substance, if it does not furnish an oil, is added to the fixed oil which it is desired to perfume, until the latter becomes agreeably fragrant; the whole is then allowed to repose for a few days, and, if any sediment falls (which should not be the case when the ingredients are pure), the clear portion is decanted into another bottle. When alcoholic essences are thus employed, the fixed oil should be gently warmed, and the admixture made in a strong bottle, so as to permit of it being corked and well agitated with safety; and in this case the agitation should be prolonged until the whole has become quite cold. In this way all the ordinary aromatised and perfumed oils of the English druggists and perfumers, as those of bergamotte, cassia, cloves, lavender, lemon, mille-fleurs, neroli, nutmeg, oranges, roses, &c., are made, but those of a few of the more delicate flowers, and of certain other substances, can only be prepared of the first quality by one or other of the processes described below.

In general, 1 to 1-1/2 dr. of the pure essential oil, or 3 to 4 fl. dr. of the alcoholic essences, are found sufficient to render 1 pint of oil agreeably fragrant, 1/2 dr. of pure attar of roses is, however, enough for this purpose, owing to the very powerful character of its perfume; but even a less quantity than this is commonly employed, on account of its costliness, the deficiency being made up by a mixture of the oils of rhodium, rosemary, and bergamotte. Most of the oils of this class are intended for hair cosmetics.

2. (By INFUSION.) Dry substances, after being reduced to powder, or sliced very small——flowers or petals, after being carefully selected, and picked from the stems and other scentless portions——and soft or unctuous matters, as ambergris, civet, or musk, after being rubbed to a paste with a little oil, either with or without the addition of about twice their weight of clean sand or powdered glass, to facilitate the reduction, are digested in the fixed oil for about 1 hour, at a gentle heat obtained by means of a water bath, continual stirring being employed all the time; the mixture is then removed from the heat, covered up, and left to settle until the next day, when the clear portion is decanted into clean bottles. When flowers are employed, the free oil is drained off, and the remainder obtained by the action of a press. The process is then repeated with fresh flowers, 5 or 6 times, or even oftener, until the oil is sufficiently perfumed. For ambergris, musk, or civet, the digestion is generally continued for 15 to 20 days, during which time the vessel is either freely exposed to the sunshine, or kept in an equally warm situation.

The first quality of the oils of ambergris, balsam of Peru, benzoin, cassia, cinnamon, civet, orange flowers, orris, roses, styrax, and vanilla, are made by infusion.

3. (BY THE FLOWERS.)——_a._ Upon an iron frame a piece of white, spongy, cotton cloth is stretched, and then moistened with almond or olive oil, usually the latter; on the cloth is placed a thin layer of the fresh-plucked flowers; another frame is similarly treated, and in this way a pile of them is made. In 24 or 30 hours the flowers are replaced by fresh ones, and this is repeated every day or every other day, until 7 or 8 different lots of flowers have been consumed, or the oil is sufficiently loaded with their odour. The oil is then obtained from the cotton cloth by powerful pressure, and is placed aside in bottles to settle, ready to be decanted into others for sale. Sometimes thin layers of cotton wool, slightly moistened with oil, are employed instead of cotton cloth.

The oils of honeysuckle, jasmin, or jessamine, jonquil, may-blossom, myrtle-blossom, narcissus, tuberose, violet, and, in general, of all the more delicate flowers, are prepared in the above manner.

_b._ The native perfumers of India prepare their scented oils of bela, chumbul, jasmin, &c., in the following manner:——A layer of the scented flowers, about 4 inches thick and 2 feet square, is formed on the ground; over this is placed a layer of moistened tel or sesamum seeds, 2 inches thick, and on this another 4-inch layer of flowers. Over the whole a sheet is thrown, which is kept pressed down by weights attached round the edges. The flowers are replaced with fresh ones after the lapse of 24 hours, and the process is repeated a third and even a fourth time, when a very highly scented oil is desired. The swollen sesamum seeds, rendered fragrant by contact with the flowers, are then submitted to the action of the press, by which their bland oil is obtained strongly impregnated with the aroma of the flowers. The expressed oil is then set aside in dubbers (bottles made of untanned hides) to settle. We have employed poppy seed in this country, in a similar manner, with great success.

_c._ The flowers are crushed in a mortar or mill, with one half their weight of blanched sweet almonds, and the next day the mass is gently heated and submitted to the action of a powerful press; the liquid thus obtained is allowed to repose for a week, when the upper portion of oil is decanted and filtered. This plan is occasionally adopted in this country for the oils of roses and of a few other flowers. (See _below_.)

The solution of a few grains of benzoic acid, or of gum benzoin (preferably the first), in any of the above oils, will materially retard the accession of rancidity, if it does not prevent it altogether.

The oils of the last two classes (2 and 3) are chiefly used to impart their respective odours to the simple oils, pomades, &c.; and in the manufacture of scented spirits or esprits. The following formulæ are given as examples of both classes of preparations:——

=Oil of Am′bergris.= From ambergris, 2 dr.; oil, 1 pint; by infusion.

=Oil of Ben′zoin.= From gum benzoin, 7 dr.; oil, 1 pint; by infusion.

=Oils for the Hair.= _Syn._ HUILES ANTIQUES, Fr. These are numerous. All those scented with the simple perfumes are prepared in the way explained under class 1 (_above_). The selection depends entirely upon the judgment of the operator or the fancy of the purchaser. In general, a mixture of two or three perfumes is preferred in these countries to the pure fragrance of any single flower, and a grossness of taste is exhibited in these matters which surprises our Continental neighbours, and the inhabitants of Italy more particularly. Some of these oils are coloured. A red tinge is given to them by allowing the oil to stand for a few hours over a little alkanet root (2 dr. to the pint) before scenting it. The application of a gentle heat facilitates the process. Yellow and orange are given by a little annotta or palm oil; and green, by steeping a little green parsley or lavender in them for a few days; or by dissolving 2 or 3 dr. of gum guaiacum in each pint by the aid of heat, and, when cold, decanting the clear portion. Huile antique au jasmin, Huile antique à la fleurs d’oranges, Huile antique à la rose, Huile antique à la tuberose, Huile antique à la violette, &c., are simple oils flavoured with the respective perfumes or their preparations.——Huile antique rouge à la rose is the ordinary oil of roses coloured with alkanet root.——Huile antique verte is simple oil coloured green, as above, and scented.——Huile antique aux millefleurs is so scented with several perfumes that none predominate. A mixture of bergamotte, lemons, lavender, neroli, pimento, and ambergris or musk, is commonly employed for the purpose.

=Oil, Macas′sar.= _Syn._ HUILE DE MACASSAR. _Prep._ 1. (Rowland’s.) Oil of ben or almonds (reddened by alkanet root), 1 pint; oils of rosemary and origanum (white), of each 1 dr.; oil of nutmeg and attar of roses, of each 15 drops; neroli, 6 drops; essence of musk, 3 or 4 drops.

2. (De Naquet.) Oil of ben, 1 quart; nut oil, 1 pint; rectified spirit, 1/4 pint; essence of bergamotte, 3-1/2 dr.; tincture of musk and esprit de Portugal, of each 2 dr.; attar of roses, 1/2 dr.; alkanet root, q. s. to colour.

=Oil, Mar′row (Perfumed).= 1. Simple marrow oil, scented at will.

2. (FLUIDE DE JAVA.) Marrow oil, coloured with a little palm oil and scented.

3. (HUILE COMOGENE.) Marrow oil, 4 oz.; spirit of rosemary, 1-1/2 oz.; oil of nutmeg, 12 drops.

4. (HUILE PHILOCOME D’AUBRIL.) Cold-drawn nut oil and marrow oil, equal parts; scent at will, q. s.

5. (HUILE DE PHÉNIX.) Clarified beef marrow, lard, pale nut oil, and expressed oil of mace, of each 4 oz.; melt together by the heat of hot water, strain through linen into a warm stone mortar, add, of oils of cloves, lavender, mint, rosemary, sage, and thyme, of each 1/2 dr.; rectified spirit, 1 oz., in which has been dissolved by a gentle heat balsam of tolu, 4 dr.; camphor, 1 dr.; triturate until the whole is cold, and then put it into bottles. All the above are used to make the hair grow, and to prevent it falling off.

=Oil of Musk.= From grain musk, 1 dr.; ambergris, 1/2 dr.; oil of lavender, 20 drops; oil, 1 pint, by infusion. A second quality is made by working the same ingredients, after the oil is poured from them, with 3/4 pint of fresh oil. This also applies to OIL OF AMBERGRIS and HUILE ROYALE.

=Oil of Musk and Am′bergris.= _Syn._ HUILE ROYALE. From ambergris, 2 dr.; grain musk, 1/2 dr.; oils of cassia, lavender, neroli, and nutmeg, of each 10 drops; oil, 1 pint; by infusion. (See _above_.)

=Oil of Sty′rax.= From liquid styrax (pure), 5 dr.; oil of nutmeg, 10 drops; ambergris, 6 gr.; oil, 1 pint; by infusion.

=Oil of Vanil′la.= _Syn._ HUILE À LA VANILLE. From purest olive or almond oil, 1-1/2 pint; vanilla (finest, in powder), 2 oz.; oil of bergamotte, 1 dr.; attar of roses (finest), 15 drops; by infusion.

=OILS (Volatile).=[64] _Syn._ OLEA DESTILLATA, OLEA DISTILLATA, OLEA ESSENTIALIA, OLEA VOLATILIA, L.; HUILES VOLATILES, Fr. The volatile oils are an extensive and important class of bodies, derived from the vegetable kingdom, and found in almost every part of the majority of the plants which produce them, except the cotyledons of the seeds, in which, in general, the fixed oils are exclusively stored up. Their presence confers upon flowers, leaves, fruit, seeds, roots, bark, and woods their peculiar and characteristic odours; but among these they are not equally distributed in the same individual, and are often altogether absent from some of them. To them we are indebted for our most delightful perfumes, and our choicest spices and aromatics. Some of them are found to possess valuable medicinal properties, and others are invested with the highest possible interest on account of their peculiar chemical constitution, and the reactions which occur when they are brought into contact with other bodies.

[Footnote 64: Although essential oils are volatile oils, volatile oils are not always essential ones as the term is understood. This is the case with the petroleum and paraffin oils obtained by the distillation of native petroleum and bituminous bodies. To describe the two as synonymous is therefore incorrect.——ED.]

The volatile oils are often called ‘essences,’ and the same loose and unmeaning term is also commonly applied to their alcoholic solutions.

_Prop._ The volatile or essential oils are usually more limpid and less unctuous than the fixed oils; but some of them are butyraceous or crystalline. Nearly all of them consist of two or more oils, differing in their sp. gr. and boiling points, one of which is generally liquid, the other, in some cases, crystalline. All of them, when perfectly pure, are colourless, though before rectification nearly the whole of them have a pale yellow tint, and some of them are brown, blue, or green. Their odour is that of the plants which yield them, and is usually powerful; their taste is pungent and burning. They mix in all proportions with the fixed oils, dissolve freely in both alcohol and ether, and are sparingly soluble in water, forming ‘perfumed’ or ‘medicated waters.’ Their boiling point usually ranges between 310° and 325° Fahr., and is always considerably higher than that of water. They resist saponification, and (excepting oil of cloves) do not combine with the salifiable bases. Their density fluctuates a little on either side of water. The lightest oil is that of citrons (sp. gr. ·847), and the heaviest that of sassafras (sp. gr. 1·096). When cooled sufficiently, they all solidify. The common temperature of the atmosphere is sufficient for this with some of them, as the oils of roses and aniseed; whilst others require to be cooled below the freezing point of water before they assume the solid form. In this state they appear to consist of a crystalline or semi-crystalline substance (stearopten, stearessence), and a fluid portion (eleopten, oleiessence). The two may be separated by pressing the concrete oil between the folds of bibulous paper, in the cold. By exposure to the air the volatile oils rapidly absorb oxygen, and become partially converted into resin. This is the cause of the deposit that usually forms in them (especially in the expressed oil of orange) when kept in an ill-corked vessel. The solid crystalline matter which separates from them when kept in closed vessels is stearoptene.

_Class._ Chemically considered, the essential oils may be divided into three great classes:——

1. Oils composed of carbon and hydrogen only (binary volatile oils, carbo-hydrogens, hydro-carbons, terebenes, camphenes), of which oil of turpentine may be regarded as the type. These are characterised by being, as a class, less soluble in rectified spirit and in water than the other essential oils. The oils of bergamot, capivi, cubebs, elemi, hops, juniper, lemons, orange peel, pepper, the grass oil of India, the laurel oil of Guiana, and some others, belong to this class.

2. Oils containing carbon, hydrogen, and oxygen (oxygenated oils), including most of those used in medicine and perfumery. These, as a class, are more soluble in rectified spirit and in water than those containing carbon and hydrogen only. To this class belong the oils of almonds, aniseed, cassia, cedar-wood, cinnamon, cumin, jasmin, lavender, meadow-sweet (_Spirœa ulmaria_), orange flowers, pennyroyal, peppermint, spearmint, rosemary, rose-petals, valerian, winter green (_Gaultheria procumbens_), and others too numerous to mention. A few of these oxygenated oils contain nitrogen.

3. Oils containing sulphur (sulphuretted oils). These are characterised by their extreme pungency, suffocating odour, vesicating power, property of blacking silver, and being decomposed by contact with most other metallic bodies. The oils of assafœtida, black mustard seed, garlic, horseradish, and onions, are of this kind. Some sulphuretted oils contain nitrogen.

_Prep._ The volatile oils are generally procured by distilling the odoriferous substances along with water; but in a few instances they are obtained by expression, and still more rarely by the action of alcohol.

According to the common method of proceeding, substances which part freely with their oil are put into the still along with about an equal weight of water, and are at once submitted to distillation. Those substances which give out their oil with difficulty are first soaked for 24 hours, or longer, in about twice their weight of water, to each gallon of which 1 lb. of common salt has been added, in order to raise its boiling point. The distillation is conducted as quickly as possible, and, when one half the water has come over, it is returned into the still, and this cohobation is repeated, when necessary, until the distilled water ceases to be mixed with oil. The heat of steam or a salt-water bath should be preferably employed. When a naked fire is used, the still should be deep and narrow, by which means the bottom will be better protected by the gradually decreasing quantity of water towards the end of the process, and empyreuma prevented. When the distilled water is to be repeatedly cohobated on the ingredients, a convenient and economical plan is to so arrange the apparatus that, after the water has separated from the oil in the receiver, it shall flow back again into the still. An ordinary worm-tub, or other like condensing apparatus, may be employed; but in the case of those oils which readily solidify, the temperature of the water in the condenser must not fall below about 55° Fahr.

The mixed vapours which pass over condense and fall as a milky-looking liquid into the receiver. This separates after a time into two portions, one of which is a solution of a part of the newly eliminated oil in water, and the other is the oil itself. The latter either occupies the upper or the lower portion of the receiver, according as its specific gravity is less or greater than that of distilled water. The separation of the oil and water is effected by allowing the mixed liquids to drop into a ‘Florentine receiver’ (see _engr._) when the oil is the lighter of the two, by which means the latter accumulates at _a_, and the water flows over by the spout _b_.

The same receiver may be employed for oils heavier than water, by reversing the arrangement; but a glass ‘separator’ (see _engr._) is, in general, found more convenient. In this case the oil accumulates at the bottom of the vessel, and may be drawn off by the stop-cock provided for the purpose.

The essential oils of lemons and oranges of commerce, and of some other fruits, are chiefly obtained by submitting the yellow rind to powerful pressure; but in this way they are not so white, nor do they keep so well, as when distilled, although in the case of the fruits referred to the oils are more fragrant than when prepared by any other method.

The London College excluded the usual directions for the preparation of the essential oils from their Pharmacopœia of 1851, on the ground that these substances are seldom prepared by the druggist or apothecary, or at all on the small scale.

“The fruit of anise, caraway, and juniper, the flowers of chamomile, lavender, and elder, the berries of allspice, the tops of rosemary, and the entire recent plants of the other herbs, are to be employed.” “Put any one of these into an alembic, then pour in as much water as will cover it, and distil the oil into a large vessel, kept cool.” (Ph. L. 1836.)

The Edinburgh College directs——“As much water only is to be employed as will prevent empyreuma during the distillation. The distillation may be immediately commenced after a proper maceration, and the oil afterwards separated from the water,” in the manner already noticed.

“It is also necessary to observe, in preparing these oils, as well as the distilled waters, that the quality of the substances, their texture, the season of the year, and similar circumstances, must occasion so many differences, that it is scarcely possible to give any certain and general rules which shall strictly apply to every example. Many things, therefore, must be regulated by the judgment of the operator.”

The Dublin College directs the vegetable substances to be macerated in the still with about 5 times their weight of water, for 24 hours, when one half of the water is to be drawn over. The oil having been separated from this in the usual manner, it is to be returned to the still, and the same quantity drawn over, as before, from which the oil must again be separated.

Chevallier gives the following rules for the distillation of essential oils:——

1. Operate upon as large quantities as possible, in order to obtain a greater product, and one of finer quality.

2. Conduct the distillation rapidly.

3. Divide the substances minutely, in order to facilitate the extrication of the oil.

4. Employ only sufficient water to prevent the matter operated on from burning, and the product from being contaminated with empyreuma.

5. For substances whose oil is heavier than water, saturate or nearly saturate the water in the still with common salt, to raise the boiling point, and thus to enable the vapour to carry over more oil.

6. Employ, when possible, water which has been already distilled from off the same substances, and has thus become saturated with oil.

7. For oils naturally fluid, keep the water in the refrigerator cool; but for those oils which easily become solid, preserve it at 80° to 90° Fahr.(?)

To the above may be added——

8. Collect the oil as soon as possible after it separates from the water with which it passes over, and in its subsequent treatment keep it, as much as possible, from free contact with the air.

Dr Ure remarks, “The narrower and taller the alembic is, within certain limits, the greater will be the proportion of oil, relative to that of the aromatic water, from like proportions of aqueous and vegetable matter employed.” “Some place the plants in baskets, and suspend these immediately over the bottom of the still, under the water, or above its surface in the steam; but the best mode, in my opinion, is to stuff an upright cylinder full of the plants and drive down through them steam of any desired force, its tension and its temperature being further regulated by the size of the outlet-orifice leading to the condenser. The cylinder should be made of strong copper, tinned inside, and encased in the worst conducting species of wood, such as soft deal or sycamore.”

The newly distilled oils may be separated from adhering water, which frequently renders them partially opaque or ‘cloudy,’ by repose in a temperature between 60° and 70° Fahr., and subsequent decantation; but to render them quite dry (anhydrous), it is necessary to let them stand over some fragments of fused chloride of calcium. This is not, however, required with the commercial oils.

The rectification of the volatile oils is commonly performed without water, by the careful application of a heat just sufficient to make them flow over pretty rapidly, so that they may be kept heated for as short a time as possible. One half, or at most two thirds only, is drawn off, that left in the retort being usually mixed with raw oil intended to be sold in that state. This method often leads to much loss and disappointment, and we have known more than one rather dangerous explosion result from its use. A better plan is to rectify the oil from strong brine, and then to separate any adhering water, either by repose or chloride of calcium.

_Pres._ Volatile oils should be preserved in well-closed and nearly full bottles, in the shade, and should be opened as seldom as possible. By age they darken, lose much of their odour, increase in density, and become thick and clammy. It is then necessary to distil them, by which the undecomposed portion is separated from the resin. Agitation along with animal charcoal will restore their clearness and original colour, but nothing more.

_Pur., Tests._ The essential or volatile oils of commerce are very frequently adulterated with the fatty oils, resins, spermaceti, or alcohol, or with other essential oils of a cheaper kind or lower grade. The presence of the first three of these may be readily detected by placing a drop of the suspected oil on a piece of white paper, and exposing it for a short time to heat. If the oil is pure, it will entirely evaporate; but if adulterated with one of these substances, a greasy or translucent stain will be left on the paper. These substances also remain undissolved when the oil is agitated with thrice its volume of rectified spirit.

The presence of alcohol may be detected by agitating the oil with a few small pieces of dried chloride of calcium. These remain unaltered in a pure essential oil, but dissolve in one containing alcohol, and the resulting solution separates, forming a distinct stratum at the bottom of the vessel. When only a very little alcohol is present, the pieces merely change their form, and exhibit the action of the solvent on their angles or edges, which become more or less obtuse or rounded.

Another test for alcohol in the essential oils is the milkiness occasioned by agitating them with a little water, as well as the loss of volume of the oil when it separates after repose for a short time.

A more delicate test of alcohol in the essential oils than either of the preceding is potassium, as employed by M. Beral:——12 drops of the oil are placed on a perfectly dry watch-glass, and a piece of potassium, about the size of an ordinary pin’s head, set in the middle of it. If the small fragment of metal retains its integrity for 12 or 15 minutes, no alcohol is present; but if it disappears after the lapse of 5 minutes, the oil contains at least 4% of alcohol; and if it disappears in less than 1 minute, it contains not less than 25% of alcohol.

Boettger states that anhydrous glycerin possesses the property of dissolving in alcohol, without mixing with the volatile oils. The mode of applying the glycerin is as follows:——The oil to be examined is well shaken in a graduated tube, with its own volume of glycerin (sp. gr. 1·25). Upon being allowed to settle, the mixture separates into two layers. The denser glycerin separates rapidly, and if the essence has been mixed with alcohol, this is dissolved in the glycerin, the augmentation in the volume of glycerin showing the proportion of alcohol present.

This species of adulteration is very common, as it is a general practice of the druggists to add a little of the strongest rectified spirit to their oils, to render them transparent, especially in cold weather. Oil of cassia is nearly always treated in this way.

The admixture of an inferior essential oil with one more costly may be best detected by pouring a drop or two on a piece of porous paper or cloth, and shaking it in the air, when, if occasionally smelled, the difference of the odour at the beginning and the end of the evaporation will show the adulteration, especially if the added substance is turpentine. The presence of the latter may also be detected by agitating the oil with rectified spirit, when it will remain undissolved.

The following method, which may also be used as a test for the presence of turpentine, is based upon its power of dissolving fats:——Take about 50 gr. of oil of poppy in a graduated glass tube, and add an equal quantity of the sample of essential oil. Shake the mixture up thoroughly and then allow it to stand; if the essential oil be pure, the mixture becomes milky, and does not clear until after several days have passed, whereas it will remain transparent if even so little as 5 per cent. of essence of turpentine be present.

The purity of essential oils may likewise, in many cases, be determined by taking their sp. gr.; or, with still greater accuracy and convenience, by measuring their index of refraction, as suggested by Dr Wollaston. A single drop of oil is sufficient for the application of the last method.

The adulteration of a heavy oil with a light one, or the reverse, may be detected by agitating the suspected oil with water, when, in most cases, the two will separate and form distinct strata.

Miss Crane believes that the cohesion figures afforded by the volatile oils, like those of the fixed ones, will be found useful indications of their purity. The application of her method is precisely similar to that followed in her examination of the fixed oils as already described. She finds that——

_Oil of Turpentine_, by itself, spreads instantly to the whole size of the plate (a common soup plate), and almost immediately the edge begins to break into irregular shapes, when a rapid motion takes place over the surface of the film, and there seems to be a contest between the cohesion of the oil particles and the adhesion between them and the water. The oil makes repeated efforts to gather itself closer together, when the water instantly reacts, giving a wavy appearance to the whole figure.

The play of colours at this point is beautiful, and serves to bring out the lines more perfectly. In a few seconds innumerable little holes appear over the surface, which soon are separated only by threaded lines, and the figure is like the most exquisitely fine lace.

_Oil of Cinnamon_ forms a figure not more than half the size of the last-named. In a few seconds small portions are detached, and shortly separate into distinct drops, four or five larger, and a number of smaller ones, scattered about. With mixtures in different proportions of _oil of turpentine_, the figures formed differently, taking more of the characteristics of the adulterant as it predominated.

_Oil of Nutmeg_ forms a large figure instantly, the edge showing a beaded line. It gathers itself together and spreads again, very like oil of turpentine, but the surface presents more the appearance of watered silk. Within sixty seconds some holes appear, and in eighty more the surface is covered with them; these scarcely spread to more than a sixteenth of an inch in diameter, but from the first each is bordered with a dotted edge. The figure lasts some time without changing materially, except the openings lengthen out into an oblong shape, remaining entirely distinct. The play of colours is very fine. With the addition of one third of the _oil of turpentine_, the first spreading is little different, but openings appear in half the time, and the dotted border does not come as soon; in about four minutes the figure is most characteristically marked, and soon breaks up entirely, this being the distinctive difference between the pure oil and the mixture.

_Oil of Peppermint_ spreads instantly to a large figure, and in ten or fifteen seconds openings appear, which increase rapidly in size. At first they look somewhat like the last-named, but are not nearly so numerous, and the border soon is more like tiny drops. In one and a half or two minutes they begin to run together, and the figure breaks up.

With the addition of _turpentine oil_ the figure forms more slowly, and the breaking up is less rapid, but in five minutes the outlines only remain.

_Oil of Bergamot_ spreads instantly; in thirty seconds tiny openings appear, not very abundant, and increase in size slowly; in five minutes they are not larger than _oil of nutmeg_ at one and a half minute. At first they have a dotted border, but as they increase in size this changes to a scalloped film, which spreads, until, in eight or ten minutes, they are joined together over the whole surface. This, with the _turpentine oil_, gives a watered surface in spreading, much more marked, and with a fine play of colours.

_Uses, &c._ The volatile oils are chiefly used by perfumers and rectifiers, and in medicine. Some of the cheaper kinds are largely employed as vehicles for colours, and in the manufacture of varnishes. The dose of the aromatic and carminative oils is from 1 to 10 drops, on sugar, or dissolved in a little weak spirit. This does not apply to oil of bitter almonds, the dose of which is 1/4 to 1/2 a drop.

⁂ The following list includes short notices of nearly all the volatile oils which have been examined, as well as of some other substances of a similar character, which commonly pass under the name.

=Oil of Allia′ria.= From the roots of _Alliaria officinalis_, or sauce-alone. Identical with the oil of black mustard.

=Oil of All′spice.= See OIL OF PIMENTO.

=Oil of Al′monds.= See OIL OF BITTER ALMONDS.

=Oil of American Arbor Vitæ.= _Syn._ HUILE CEDRE BLANC, Fr. From the fresh tops of _Thuja occidentalis_, or American arbor-vitæ tree. Yellow; fragrant; stimulant. Used in frictions for rheumatism. _Prod._ 1-1/2 to 2% (nearly).

=Oil of Angel′ica.= From the dried root of _Angelica Archangelica_. _Prod._ 25% (fully).

=Oil of An′iseed.= _Syn._ OLEUM ANISI (Ph. L., E., & D.), O. ESSENTIALE ANISI, L. From the fruit (seeds) of _Pimpinella anisum_, or anise. Nearly colourless. It is very frequently adulterated with one or other of the cheaper oils, in which case spermaceti or camphor is added to it, to make it ‘candy.’

_Prop., &c._ When pure it congeals into a solid crystalline mass on being cooled to 50° Fahr., and does not melt again until heated to about 63°. Treated with iodine, it quickly congeals into a solid hard mass, with a perceptible increase of temperature, and the development of orange-coloured and grey fumes. Sulphuric acid, with heat, turns it of a rich purple-red colour, and the compound soon afterwards becomes inspissated and hard (resinified). In alcohol of ·806 it is soluble in all proportions, but rectified spirit (·838) dissolves only 42% of this oil. Sp. gr. (recent) ·9768; (one year old) ·9853 to ·9855; (old) ·9856 to ·9900. The foreign oil is generally the heaviest.

Oil of aniseed is carminative and pectoral; and both itself and preparations have long been in favour with the masses in coughs, colds, &c. In preparing it care must be taken that the temperature of the water in the receiver and refrigerator does not fall lower than about 68° Fahr. _Prod._ (From the dried fruit of commerce) avoir. 2% (nearly). See OIL OF STAR-ANISE.

=Oil, Ap′ple.= See AMYL (Valerianate of), and ESSENCE OF APPLE.

=Oil of Ar′nica.= _Syn._ OLEUM ARNICÆ, O. A. RADICUM, L. From the roots of _Arnica montana_. Yellowish brown. Sp gr. ·940. Prod. 16 lbs. yielded 1 oz. of oil. The oil from the flowers of arnica is blue.

=Oil of Asarabac′ca.= _Syn._ OLEUM ASABI, O. ASARI LIQUIDUM, L. From the roots of _Asarum Europæum_. Yellow; glutinous. Two butyraceous oils pass over at the same time.

=Oil of Assafœt′ida.= _Syn._ OLEUM ASAFŒTIDA, L. From the gum resin. Contains sulphur. Very fetid and volatile.

=Oil of Balm.= _Syn._ OLEUM MELISSÆ, L. From the herb (_Melissa officinalis_). Pale yellow; fragrant. Sp. gr. ·970 to ·975. _Prod._ 100 lbs. of the fresh flowering herb yielding 1/4 oz. of oil (M. Raybaud). A mixture of oil of lemons and rosemary is commonly sold for it.

=Oil of Balsam of Peru.= See CINNAMEINE.

=Oil of Ber′gamot.= _Syn._ BERGAMOT, ESSENCE OF B.; OLEUM BERGAMII, O. BERGAMOTÆ, L. By expression from the yellow portion of the rind of the fruit of _Citrus Bergamia_, or bergamot orange. Pale greenish yellow; highly fragrant. It is obtained purer by distillation, but its perfume is then slightly less delicate. Sp. gr. ·875 to ·885. _Prod._ The rind of 100 bergamot oranges yielded by distillation nearly 3 oz. of oil. (M. Raybaud.)

Oil of bergamot is frequently adulterated with rectified spirit, or with the oils of lemons, oranges, or turpentine. The presence of these substances may be detected in the manner explained under OILS (Volatile), _Purity and Tests_ (_anté_), as well as by the altered density of the oil. Pure bergamot oil is much more soluble in rectified spirit than either of the others, and is further distinguished from them by its free solubility in solution of potassa, forming a clear solution.

=Oil of Bit′ter Almonds.= _Syn._ ESSENCE OF B. A.; OLEUM AMYGDALÆ AMARÆ, O. A. ESSENTIALE, L. From the ground cake of bitter almonds from which the fixed oil has been expressed. The common plan is to soak the cake (crumbled to fragments) for about 24 hours in twice its weight of water, to which 1/3rd or 1/4th of its weight of common salt has been added, and then to submit the whole to distillation, allowing the first half of the water that passes over to deposit its oil, and to run back again into the still. Pale golden yellow; colourless when rectified; tastes and smells strongly nutty, like peach-kernels. It consists of 85% to 90% of hydride of benzoyl and 8% to 12% of hydrocyanic acid, with a variable quantity of benzoic acid and benzoin. The density varies a little with the age of the oil, and the temperature and rapidity with which it has been distilled. Sp. gr. (recent) 1·0525; (trade crude oil) 1·079 (G. Wippel); (old) 1·081 (1·0836——Pereira). “Essential oil of almonds, free from adulteration, should have a sp. gr. at most of 1·052.” (Ure.) According to Prof. Redwood, the density may vary from 1·0524 to 1·0822. The light oil contains the most hydride of benzoyl, and the heavy oil the most benzoin. _Prod._ From less than ·2 to ·5%.

_Pur._ This oil is generally adulterated with cheaper oils, and in nearly every case with alcohol. When it is pure——Mixed with oil of vitriol, it strikes a clear crimson-red colour, without visible decomposition,——Mixed with an alcoholic solution of potassa, crystals are eliminated.——Iodine dissolves only partially and slowly in it, without further visible results.——Chromate of potassa does not affect it.——Nitric acid (sp. gr. 1·42) causes no immediate reaction, and in the course of 3 or 4 days crystals of benzoic acid begin to appear; but if only 8% or 10% of alcohol or rectified spirit is present, a violent effervescence speedily commences, and nitrous fumes are evolved. By using nitric acid, sp. gr. 1·5, the smallest quantity of alcohol may be detected.

_Obs._ This oil does not pre-exist in the almond, but is formed by the action of water on a peculiar crystallisable substance, called amygdalin. It is essentially the hydride of benzoyl, but it always contains a portion of hydrocyanic or prussic acid, to which it owes its very poisonous properties. It is occasionally employed as a substitute for hydrocyanic acid in medicine; but its principal consumption is as a flavouring ingredient and a perfume by cooks, confectioners, liquoristes, and perfumers. For this purpose it is dissolved in rectified spirits. See ESSENCE.——_Dose_, 1/4 to 1 drop.

An oil closely resembling that from bitter almonds is obtained by distillation from the leaves of the peach and cherry-laurel, the bark of the plum-tree, the bruised kernels of cherries, plums, and peaches, the pips of apples, and from several other vegetable substances that possess a nutty odour and flavour.

A NON-POISONOUS OIL OF ALMONDS has been introduced. This is simply the ordinary oil of commerce freed from hydrocyanic acid, and is intended to be substituted for the crude, poisonous oil for domestic purposes. Unfortunately, the purified essence does not keep well, and is often converted after a few months into little else than a solution of benzoic acid, almost devoid of the usual odour and flavour of the bitter almond. “No wonder, then, under such circumstances, that the public preferred the preparations they had been accustomed to, which were not so liable to change.” (Redwood.) The following methods have been adopted for this purpose:——

1. (Liebig.) Agitate the crude distilled oil with red oxide of mercury, in slight excess, and after a few days’ contact, rectify the oil from a little fresh oxide of mercury. The product is quite pure, when the process is properly managed. The cyanide of mercury thus formed may be either employed as such, or reconverted into mercury and hydrocyanic acid.

2. (Mackay.) Commercial oil of almonds, 1 lb.; fresh-slaked lime, q. s. to form a milk-like liquid; afterwards add, of solution of potassa, 1-1/2 lb.; water, 3 pints; agitate occasionally for 48 hours, then distil over the oil, and rectify it from a fresh mixture of lime and potassa.

3. (Redwood.) The oil is mixed with an equal quantity of water, and the mixture is digested in a water bath with red oxide of mercury, and small quantities of fresh-slaked lime and protochloride of iron, with as little access of air as possible; as soon as decomposition of the acid has taken place, the whole is introduced into a copper retort, and submitted to distillation. The product is perfectly free from hydrocyanic acid. The first process is, however, the simplest, cheapest, and best.

The sp. gr. of this non-poisonous oil is 1·051. (G. Whippell.) That of pure colourless hydride of benzoyl is 1·043; it boils at 356° Fahr., is soluble in 35 parts of water, and in all proportions in alcohol and ether. Exposed to the air, it greedily absorbs oxygen, and becomes converted into a mass of crystallised benzoic acid. The purified oil of almonds does the same, only less rapidly.

=Oil of Almonds (Facti′′tious).= _Syn._ ESSENCE OF MIRBANE, NITROBENZOL. The preparation of this article on the small scale is explained under NITROBENZOL. It is now extensively prepared as a substitute for the oil of almonds obtained by distillation. The following is Mansfield’s process:——The apparatus consists of a large glass worm, the upper end of which is divided into two branches, gradually dilating so as to form two funnel-shaped tubes. Into one of these concentrated nitric acid is poured, and into the other benzol, which need not, for this purpose, be chemically pure. These bodies meet at the point of junction of the two tubes, and the rate of their flow is regulated by any appropriate means. Chemical reaction instantly takes place, and the new compound is cooled by its passage through the worm, which is refrigerated for the purpose. It has then only to be washed with water or a very weak solution of carbonate of soda for the process to be complete. The product has the sp. gr. 1·209, boils at 415° Fahr., has an intensely sweet taste, and an odour closely resembling, but not actually identical with, that of oil of bitter almonds. Unlike genuine oil of almonds or hydride of benzoyl, it is insoluble in water, and does not distil without suffering partial decomposition. It is chiefly used to scent soaps, and to adulterate the genuine oil. The benzol for this purpose is obtained from coal-tar. See BENZOL and NITROBENZOL.

=Oil of Boxwood.= (Ph. L. 1746.) _Syn._ OLEUM BUXI EMPYREUMATICUM. Distilled from fragments of boxwood in a retort, with a sand bath gradually increased in heat. Anodyne, antispasmodic, and diaphoretic.——_Dose_, 10 to 20 drops. (Jourdan says 4 to 5 drops in gonorrhœa.) It relieves toothache.

=Oil, Brandy.= See OIL OF GRAPE.

=Oil of Bu′chu.= _Syn._ OLEUM BAROSMÆ, O. DIOSMÆ, L. From the leaves of _Diosma crenata_. Yellow; lighter than water; smells of the leaves.

=Oil of Caj′eput.= _Syn._ CAJEPUTI OIL, KYAPOOTIE O.; CAJEPUTI OLEUM (B. P.), OLEUM CAJEPUTI (Ph. L. E. & D.), L. From the dried leaves of the _Melaleuca Cajeputi_ (_Melaleuca minor_, B. P.). Colourless, when pure (that of commerce is usually green); odorous; aromatic; taste hot and penetrating. Its odour has been compared to a mixture of those of camphor and cardamoms. It boils at 343° Fahr. Sp. gr. ·925 to ·927. When rectified, about 3/4ths of the quantity passes over colourless, and has the density ·897; the remaining portion is green, and has the density ·920 to ·925. Its green colour is derived from chloride of copper, the presence of which may be recognised by the red precipitate occasioned by agitating the oil with a solution of ferrocyanide of potassium. (Guibourt.) From the East Indies.

Pure oil of cajeput is slightly soluble in water; entirely and freely soluble in alcohol; dissolves iodine; and when dropped on water, rapidly diffuses itself over the surface, and soon completely evaporates. A spurious kind (FACTITIOUS OIL OF CAJEPUT), made of oil of rosemary, flavoured with camphor and the oils of peppermint and cardamoms, and coloured with verdigris, is occasionally met with in the shops.

Oil of cajeput is a powerful antispasmodic and diffusible stimulant.——_Dose_, 3 to 6 drops, on sugar; in cholera, colic, epilepsy, hysteria, rheumatism, spasms, toothache, &c.

=Oil of Cam′phor.= _Syn._ LIQUID CAMPHOR; OLEUM CAMPHORÆ, O. C. VOLATILE, L. Obtained from incisions in the wood of the camphor tree of Borneo and Sumatra (_Dryobalanops aromatica_), in which it exists in cavities in the trunk; also by distillation from the branches of the _Camphora officinarum_, or laurel camphor tree. Colourless when rectified. Sp. gr. ·910. _Prod._ 60 lbs. of the crude brown oil yields 40 lbs. of pure white oil and 20 lbs. of camphor. It rapidly oxidises in the air. Used to scent soap. See CAMPHOR (Liquid).

=Oil of Car′away.= _Syn._ OLEUM CARUI (B. P. Ph. L. E. & D.), O. C. ESSENTIALE, L. From the fruit of _Carum Carui_ (caraway seeds). Nearly colourless; aromatic; carminative. Sp. gr. ·940; (old) ·946 to ·950. _Prod._ Av. 5% (nearly). It is frequently adulterated with oil of cumin. Added to purgative medicines to prevent griping.

=Oil of Car′damoms.= _Syn._ OLEUM CARDAMOMI, O. C. ESSENTIALE, L. From the seed of _Elettaria cardamomum_, or true cardamom. Colourless; fragrant; carminative. Sp. gr. ·943. _Prod._ 5% (nearly). The capsules (‘lesser cardamoms’) yield only about 1% of oil. (M. Raybaud.)

=Oil of Cascaril′la.= _Syn._ OLEUM CASCARILLÆ, L. From the bark of _Croton eleuteria_ (Swartz.), or cascarilla tree. Very fragrant. _Prod._ ·4% to ·75%.

=Oil of Cas′sia.= _Syn._ OIL OF CHINA CINNAMON; OLEUM CASSIÆ (Ph. E.), L. From cassia buds, or from cassia bark, Golden yellow; aromatic; fragrant. It is generally adulterated with rectified spirit. Nitric acid converts the pure oil into a crystalline mass. Sp. gr. 1·071 to 1·073; (old) 1·078 to 1·090 _Prod._ From the buds of 1% (barely); from the bark of commerce, ·75%. It is frequently sold for oil of cinnamon.

=Oil of Cebadil′la.= _Syn._ OIL OF SABADILLA; OLEUM CEBADILLÆ, L. A green butyraceous matter, obtained from _Asagræa officinalis_.

=Oil of Ce′dar-wood.= From the wood of a species of _Cedrus_. It consists of two hydrocarbons. One, a volatile liquid (cedrene), and the other a solid, crystalline compound containing oxygen. _Prod._ ·2% to 25%.

=Oil of Ce′drat.= _Syn._ ESSENCE OF CEDRA; OLEUM CEDRI, O. CITRI FINUM, L. From the exterior yellow rind of the fruit of _Citrus medica_ (Risso), or citrons, either by expression or distillation, as oil of bergamot. The first portion of oil that comes over is colourless; the latter portion greenish. Very fragrant. Sp. gr. ·847. _Prod._ 100 citrons yield nearly 1 fl. oz. of pale, and 1/2 fl. oz. of green oil. See OIL OF CITRON (_below_).

=Oil of Cel′ery Seed.= _Syn._ OLEUM APII. L. From the fruit (seed) of _Apium graveolens_. Diuretic; stimulant. _Prod._ 3/4% to 1% (nearly).

=Oil of Cham′omile.= _Syn._ OIL OF ROMAN CHAMOMILE; OLEUM ANTHEMIDIS (Ph. L. E. & D.), O. CHAMÆMELI, O. C. FLORUM, O. ESSENTIALE EX FLORIBUS C., L. From the flowers of _Anthemis nobilis_. In the Ph. L., English oil of chamomile (ANTHEMIDIS OLEUM ANGLICUM) is ordered. Blue; turns yellow and brown by exposure and age; odour characteristic. Sp. gr., English (from the flowers), ·9083; foreign, ·9289. _Prod._ Fresh flowers, ·1% (barely); recently dried (finest commercial), 5%; av. of 6 dried samples, ·25% (nearly). If much water is employed, even the above small quantities of oil will not be obtained.

Oil of chamomile is reputed antispasmodic, tonic, and stomachic. 1 to 3 drops on a lump of sugar, taken just before retiring to rest, is an excellent preventive of nightmare, and will frequently induce quiet sleep where more active substances have failed. Unfortunately, the oil of the shops is generally either adulterated or old, and commonly both, in which case the oil acts as an irritant. A common plan is to mix it with old oil of lemons, a fraud which may be detected by the lessened density of the oil, and by its diminished solubility in rectified spirit.

=Oil of Cher′ry-laurel.= _Syn._ OLEUM LAURO-CERASI, L. From the leaves of _Cerasus Laurocerasus_, or common laurel. Closely resembles oil of almonds, but is said to be weaker. Like that substance, it is powerfully poisonous. _Prod._ 100 lbs. fresh leaves (undeveloped, June), 10·13 oz.; do. (half grown, June), 7·2 oz.; do. (full-grown, 8 weeks on tree, July), 4·96 oz.; do. (do., 3 months on tree, Sept.), 7·04 oz.; do. (15 months on tree), 2·24. (Christison.)

=Oil of Cher′vil.= _Syn._ OLEUM CHÆROPHYLLI, L. From the bruised fresh herb, macerated for 2 or 3 days in salt and water, and then distilled.

=Oil of Cincho′na.= _Syn._ OLEUM CINCHONÆ, L. From cinchona bark. Butyraceous; smells of the bark. 20 lbs. yield only 2 gr. (Trommsdorff.) The odour of bark is imitated by a solution of turmeric in potash, and by chloride of iron.

=Oil of Cin′namon.= _Syn._ HYDRIDE OF CINNAMYL; OLEUM CINNAMOMI (B. P., Ph. L. E. & D.), O. C. VERI, L. From the bark of _Cinnamomum zeylanicum_, macerated for several days in salt and water, and then distilled. Yellowish or red; very aromatic; both odour and taste resemble that of the bark. Sp. gr. 1·035. _Prod._ 11 lbs. yielded 1 oz.; 100 lbs. yielded 1·56 oz. (M. Raybaud.)

_Pur._ Oil of cinnamon, owing to its high price, and the consequent premium for its adulteration, can scarcely be obtained pure from the shops of this country. Oil of cassia and highly rectified spirit are the substances usually employed for this purpose. The increased sp. gr. resulting from the first, and the diminished sp. gr. from the second, afford ready means of detecting these frauds. The presence of oil of cassia may also be detected by an experienced person by the odour, which differs a little from that of pure oil of cinnamon. Oil of cassia is less limpid than oil of cinnamon, and it stands a greater degree of cold without becoming turbid or congealing. “Wine-yellow, when recent; cherry-red, when old; odour purely cinnamonic; nitric acid converts it nearly into a uniform crystalline mass.” (Ph. E.) During this reaction the odour of bitter almonds is perceptible. Both oil of cassia and oil of cinnamon are thus converted into a brown balsam; with oil of cassia, however, a brisk decomposition occurs sooner, and at a slighter heat. It also forms a crystalline compound with ammonia. These reactions, unfortunately, are not characteristic. “The most distinguishing characteristic of the cinnamon oils is, perhaps, their relation to the alcoholic solution of caustic potash. Both dissolve in it readily and clear, with a reddish, yellowish-brown colour; after some time, however, the solution becomes very turbid, and a rather heavy undissolved oil precipitates, when the solution gradually becomes clear again. (Ure.) The palest oil is considered the best.

_Obs._ Oil of cinnamon is chiefly imported from Ceylon, where it is distilled from bark that is unfit for exportation. The dark coloured oil is usually rectified, when two pale oils are obtained, one lighter, and the other heavier, than water; but 10% of oil is lost by the process. The oil distilled from the root of the tree (O. CINNAMOMI RADICIS) is much weaker than that from the bark. The oil from the leaves (O. C. FOLIORUM), also imported from Ceylon, smells of cloves, but has a less density than oil of cloves.

Oil of cinnamon consists essentially of hydride of cinnamyl, but, unless when very recently prepared, it also contains a variable proportion of cinnamic acid formed by the oxidation of the hydride.

=Oil of Cit′ron.= _Syn._ ESSENCE OF CITRON; OLEUM CITRI, L. From the lees of citron juice; or, from the peels, as oil of lemons or bergamot. The last generally goes by the name of oil of cedrat. Both are fragrant. (See _above_.)

=Oil of Citron-flowers.= _Syn._ OLEUM CITRI FLORUM, L. Amber-coloured; highly fragrant. _Prod._ 60 lbs. yield 1 oz.

=Oil of Cloves.= _Syn._ ESSENCE OF CLOVES; OLEUM CARYOPHYLLORUM, O. CARYOPHYLLI (B. P., Ph. L. E. & D.), O. EUGENIÆ C. (Ph. D. 1826), L. From the unexpanded flowers (cloves) of the _Caryophylus aromaticus_, or Molucca clove-tree, soaked for some time in salt and water, and then submitted to distillation; the distilled water, after having deposited its oil, being returned 3 or 4 times into the still, and again ‘worked off’ from the same materials. Nearly colourless, when recent, gradually becoming pale yellow and ultimately light brown, by age; highly aromatic, with the characteristic odour and flavour of cloves. It is the least volatile of all the essential oils. Sp. gr. 1·055 to 1·061 (1·034 to 1·061, B. P.). _Prod._ 16% to 22%.

_Pur._ Oil of cloves is frequently adulterated with inferior essential oils, especially with those of pimento, pinks, and clove-gilly flowers, and, occasionally, with castor oil.——1. Pure oil of cloves forms a butyraceous coagulum when shaken with pure liquor of ammonia, which crystallises after fusion by a gentle heat.——2. Treated with an alcoholic solution of potassa, it entirely congeals into a crystalline mass, with total loss of its characteristic odour.——3. Shaken with an equal volume of strong caustic soda lye, it forms, on repose a mass of delicate lamellar crystals——4. Solution of chromate of potassa converts it into brown flakes, whilst the salt loses its yellow colour.——5. Chlorine turns it first green, and then brown and resinous.——6. Nitric acid turns it red, and a reddish-brown solid mass is formed; with heat, it converts it into oxalic acid.——7. It dissolves freely in sulphuric acid (oil of vitriol), yielding a transparent, deep reddish-brown solution, without any visible decomposition.——8. Mixed, gradually, with about 1/3rd of its weight of oil of vitriol, an acid liquor is formed, together with a resin of a rich purple colour, which, after being washed, is hard and brittle, and forms a red tincture with rectified spirit, which is precipitated of a blood-red colour by water.——9. It dissolves iodine freely, without any marked reaction.——10. It dissolves santaline freely.——11. Mix one drop of the oil with a small trace of solution of aniline by means of a glass rod, and then shake with 5 or 6 c.c. of distilled water. By the addition of a few drops of sodium hypochlorite to the mixture the characteristic blue coloration due to phenol will be developed in a few minutes, if the adulterant be present; whereas with the pure oil nothing but the purplish-violet colour of aniline will be perceived. Stirring or shaking must be avoided after the addition of the hypochlorite. The presence of 1 per cent. of phenol can thus be demonstrated in one drop of the oil.

_Obs._ Clove oil contains a heavy oil, sp. gr. 1·079 (caryophyllic acid), and a light oil, sp. gr. ·918 (clove hydrocarbon); by rectification, much of the light oil is lost, and the product becomes denser. (1·361——Bonastre.)

=Oil, Cog′nac.= See OIL, GRAPE (_below_).

=Oil of Copai′ba.= _Syn._ OIL OF CAPIVI; OLEUM COPAIBÆ (B. P., Ph., L. & E.), L. 1. (Ph. E.) Balsam of capivi, 1 oz.; water, 1-1/2 pint; distil, returning the water into the still, until oil ceases to pass over.

2. (Wholesale.) From the crude oil which separates during the manufacture of ‘specific solution of copaiba’ and ‘soluble capivi,’ by distillation along with a little salt and water.

_Pur., &c._ Colourless when pure; that of commerce has frequently a greenish tinge, derived from the copper utensils; odour, not disagreeable when recent. Sp. gr. ·876 to ·878. _Prod._ 50% to 55%. When adulterated with oil of turpentine, its solubility in rectified spirit is greatly diminished, and the solution is turbid.——_Dose_, 10 to 15 drops, in sugar; in the usual cases in which copaiba is ordered. 20 to 60 minims, three times a day (B. P.).

=Oil of Corian′der.= _Syn._ OLEUM CORIANDRI, L. From the fruit (seeds) of _Coriandrum sativum_. Yellowish; aromatic; carminative. _Prod._ (Dried fruit) 5-1/2 to 6%.

=Oil, Corn.= The name given by Mulder to a peculiar fatty compound found in the fusel oil of the distilleries of Holland. It has a very powerful odour, resembling that of some of the umbelliferous plants, and is unaffected by caustic potassa. See OIL, FUSEL (page 772).

=Oil of Cu′bebs.= _Syn._ OLEUM CUBEBARAM, O. CUBEBÆ (B. P., Ph. E. & D.), L. From the fruit of _Cubeba officinalis_, or cubebs, coarsely ground. Aromatic, hot, and bitter tasted; odour, that of the fruit; faintly green, colourless when pure. Sp. gr. ·129. _Prod._ 9% to 11%.

_Pur., &c._ When pure, iodine has little action on this oil, and immediately gives it a violet colour, without any very marked reaction; nitric acid turns it opaque, and the mixture changes to a pale red when heated; sulphuric acid turns it of a crimson red. When adulterated with oil of turpentine, both its viscidity, solubility in rectified spirit, and its density, are lessened; when mixed with castor oil it leaves a greasy stain on paper.——_Dose_, 10 to 15 drops, in the usual cases in which cubebs in substance is given. 5 to 20 minims (B. P.), suspended in water by mucilage and sugar.

=Oil of Cumin.= _Syn._ OLEUM CUMINI, O. CYMINI, L. From the fresh fruit (seed) of _Cuminum Cyminum_, or cumin. Pale yellow; smells and tastes strongly of the seeds. Sp. gr. ·975. _Prod._ 2-1/2% to 3%.

_Obs._ Oil of cumin is a mixture of two oils differing in volatility, and which may be separated by careful distillation. The more volatile one has been named cymol; the other, cuminol.

=Oil of Dill.= _Syn._ OLEUM ANETHI (Ph. L. & E.), L. From the bruised fruit (seed) of _Antheum graveolens_. Pale yellow; odour, that of the fruit; taste, hot and pungent; carminative. Sp. gr. ·188 to ·882. _Prod._ 4% (nearly).

=Oil of El′der.= _Syn._ ATTAR OF ELDER FLOWERS; OLEUM SAMBUCI, L. From elder flowers (_Sambucus nigra_). Butyraceous; odour not very marked.

=Oil of El′emi.= _Syn._ OLEUM ELEMI, L. From the resin. Isomeric with oil of turpentine.

=Oil of Er′got.= _Syn._ ETHEREAL O. OF E.; OLEUM ERGOTÆ, O. E. ÆTHEREUM, O. SECALIS CORNUTI, L. Prepared by evaporating the ethereal tincture at a very gentle heat, and, preferably, allowing the last portion of the ether to escape by spontaneous evaporation. Brownish-yellow; lighter than water; soluble in ether and solution of potassa; only partly soluble in alcohol. It appears to be a mixture of volatile and fixed oil, with some resinous matter.——_Dose_, 10 to 20 drops, in hæmorrhages; 10 or 12 drops every 3 or 4 hours, in diarrhœa; 20 to 50 drops, as a parturifacient, &c. Externally, in rheumatism, toothache, &c.

_Obs._ The above is the oil of ergot now employed in medicine. It must not be confounded with other preparations occasionally called by the same name, but which differ from it in character. Among the latter are the following:

_a._ A fixed oil obtained by distilling off the spirit from the alcoholic tincture. It has the odour of rancid fish oil, and the distilled spirit has also a putrid odour.

_b._ A fixed oil, obtained from coarsely powdered ergot by strong pressure between iron plates, at a heat of about 212° Fahr. It is fluid, coloured, smells strongly of the drug, but is nearly destitute of its leading qualities. Both the preceding contain some volatile oil and resinous matter.

_c._ An empyreumatic oil obtained by distilling ergot _per se_. It is light brown, viscid, acrid, and nauseous.

_d._ A volatile oil obtained by digesting powdered ergot in solution of potassa at 125° Fahr., diluting the saponaceous mass thus formed with one half to an equal weight of water, neutralising the alkali with dilute sulphuric acid, and then submitting the whole to distillation in a chloride of sodium or oil bath. It is white, adhesive, butyraceous, and tasteless. It appears a product, rather than a simple educt.

_e._ This is the ethereal oil, first described, in its purest form. It is colourless, translucent, oily, and acrid-tasted, with the odour of ergot; it has a high boiling-point, at which it suffers partial decomposition, but may be volatilised at a lower temperature, like the other oils. By long exposure to heat, it thickens and partly solidifies; light and air darken it; it is lighter than water, very slightly soluble in water, but sufficiently so to impart to it its peculiar odour; it is soluble in pure alcohol, in ether, the volatile and fixed oils, alkaline lyes, liquor of ammonia, creasote, and naphtha. The dilute mineral acids clear it but do not produce any marked reaction.

=Oil, Ethe′′real.= See OIL OF WINE (_below_).

=Oil of Eucalyptus.= _Syn._ OLEUM EUCALYPTI GLOBULI. See EUCALYPTUS.

=Oil of Fen′nel.= _Syn._ OLEUM FŒNICULI (Ph. L.), O. F. OFFICINALIS (Ph. E. & D.), O. F. DULCIS, L. From the fruit or seed of _Fœniculum dulce_, or sweet fennel (Ph. L.), Colourless; odour that of the plant; tastes hot and sweetish; congeals at 50° Fahr.; carminative and stomachic. It consists of two oils; the one solid and identical with that of oil of aniseed. When treated with nitric acid, it affords benzoin, Sp. gr. ·997. _Prod._ Dried fruit (of commerce), 3% to 3·5%. The flowering herb yields ·35% of a similar oil.

_Obs._ The oil of fennel of the shops is the product of the fruit of _Fœniculum vulgare_, or common, wild, or bitter fennel. It closely resembles that of sweet fennel, but is scarcely so agreeable either in taste or smell. It is chiefly used to scent soaps.

=Oil of Firwood.= _Syn._ OLEUM PINI SYLVESTRIS. An essential oil, distilled from the leaves of _Pinus sylvestris_.

=Oil of Fleabane.= (Ph. U. S.) _Syn._ OLEUM ERIGERONIS CANADENSIS. An essential oil, distilled from _Canada erigeron_.——_Dose_, 5 minims in hæmorrhage.

=Oil, Fu′sel.= Noticed at page 772.

=Oil of Gal′banum.= _Syn._ OLEUM GALBANI (Ph. Bor.), L. From galbanum, 2 lb.; water, 16 fl. oz.; distilled together. Yellow; resembles oil of asafœtida, but milder.

=Oil of Gar′lic.= _Syn._ SULPHIDE OF ALLYL. From the bruised bulbs or ‘cloves’ of _Allium sativum_, or garlic. It possesses the peculiar odour, taste, and other properties of the bulbs, in a highly exalted degree.

_Obs._ When a mixture of oil of black mustard and sulphide of potassium is exposed in a sealed glass tube to a temperature above that of 212° Fahr., sulphocyanide of potassium and garlic oil are formed. On the other hand, when the compound of garlic oil and chloride of mercury (formed by adding to an alcoholic solution of the oil a like solution of the chloride) is gently heated with sulpho-cyanide of potassium, mustard oil, with all its characteristic properties, is called into existence.

=Oil of Gaulthe′′ria.= See OIL OF PARTRIDGE BERRY (_below_).

=Oil of Gen′tian.= _Syn._ OLEUM GENTIANÆ, L. From the root. Butyraceous; smells strongly of gentian. 3 cwt. yield 1 dr. (barely).

=Oil of Gera′′nium.= _Syn._ OIL OF GINGER GRASS, O. OF SPIKENARD. The oil of commerce which passes under this name and which was formerly imported from the East Indies, was not obtained from any species of _Geranium_ or _Pelargonium_, but probably from a species of _Andropogon_. Of recent years, however, genuine geranium oil, obtained from the rose geranium (_Pelargonium roseum_) has been and continues to be met with in our markets. This essential oil is manufactured in immense quantities, at La Trappe de Staonelli not far from the Bay of Sidi Ferruch, in Algiers, where about forty acres of the plant are in cultivation. “Three harvests are gathered every year, and each yields from 170 to 200 kilograms of oil, or equal to 500 to 600 kilograms per annum. The value of this product never falls below forty francs the kilogram, the average gross value being therefore from 20,000 to 25,000 francs or at least £20 per acre. Seven distillatory apparatus are employed in this manufactory.”[65] A finer oil is yielded by the rose geranium, when grown in France, but it is much dearer. It is often employed to adulterate otto of roses. See OIL, GRASS (_below_).

[Footnote 65: “The Paris Exhibition,” ‘Pharmaceutical Journal,’ 3rd series, No. 433.]

=Oil of Gin′ger.= _Syn._ OLEUM ZINGIBERIS, L. From the dried root (rhizome) of _Zingiber officinale_, or ginger of commerce. Bluish-green; possesses a less agreeable odour than that of good ginger, without any pungency. _Prod._ 11/16 of 1% (M. Raybaud).

=Oil of Goosefoot.= (Ph. U. S.) _Syn._ OLEUM CHENOPODII. Distilled from the seeds of _Chenopodium anthelminticum_.——_Dose._ From 4 to 8 drops, with treacle or milk, for 3 nights in succession, for children. For adult, 1/2 dr. Vermifuge.

=Oil of Grain-spirit.= _Syn._ GRAIN OIL. Two distinct substances are found in spirit distilled from fermented grain; one of which is butyraceous and highly offensive (corn oil of Mulder————?), the other liquid (crude fusel oil). The relative proportions of these substances to each other, and to the spirits which they contaminate, vary with the materials and the management of the process. The ‘GRAIN OIL’ of the London rectifiers consists chiefly of fusel or potato oil, mixed with alcohol and water, and with small and variable proportions of solid ethyl and amyl-compounds of certain fatty acids (œnanthic and margaric). The latter are said to be similar to the butyraceous matter before referred to, as well as the solid fat of the whisky distilleries conducted on the old plan. According to Mr. Rowney, the fusel oil of the Scotch distilleries contains capric acid. See OIL OF CORN (_above_), and FUSEL OIL.

=Oil, Grape.= _Syn._ BRANDY OIL, COGNAC O. This is essentially the sulphate of amyl. It is prepared by dissolving the fusel oil of marc-brandy in strong rectified spirit, and then adding concentrated sulphuric acid; alcohol and excess of acid is removed by washing the newly formed compound with water. Dissolved in rectified spirit, it forms ‘BRANDY ESSENCE,’ which is used to impart the Cognac flavour to plain spirit. See SULPHATE OF AMYL and AMYL-ETHER, also OIL OF MARC-BRANDY (_below_).

=Oil, Grass.= Several of the grasses (_Graminaceæ_) yield fragrant volatile oils. See OIL OF GERANIUM, GRASS OIL (of Namur), OIL OF LEMON-GRASS, OIL OF SPRING-GRASS, &c.

=Oil, Grass (of Namur).= _Syn._ INDIA GRASS OIL. From _Andropogon Calamus aromaticus_ (Royle), supposed to have been the “sweet cane” and “rich aromatic reed from a far country” of Scripture; formerly supposed to be obtained from _Andropogon Iwarancusa_. Stimulant and highly fragrant. See OIL OF SPIKENARD.

=Oil of Hops.= _Syn._ OLEUM LUPULI, L. From commercial hops, by distillation along with water. It may also be collected during the brewing of beer. Odorous; acrid; narcotic; soluble in water; becomes resinous by exposure and age. Sp. gr. ·910. Chiefly used to increase the aroma and flavour of old or damaged hops.

=Oil of Horse-mint.= _Syn._ OLEUM MONARDÆ (Ph. U. S.), L. From the fresh herb of _Monarda punctata_, a plant indigenous in the U.S. of America. Dark amber-coloured; fragrant; pungent; carminative; rubefacient; and vesicant.

=Oil of Horse-rad′ish.= _Syn._ OLEUM ARMORACIÆ, L. From the fresh roots of _Cochlearia armoracia_ (Linn.), or common horse-radish. Pale yellow; heavier than water; acrid; vesicant; identical with that from black mustard. _Prod._ ·5% (nearly).

=Oil of Hyssop.= _Syn._ OLEUM HYSSOPI, L. From the flowering herb of _Hyssopus officinalis_. Aromatic; stimulant. _Prod._ ·25% to ·33%.

=Oil of Jargonelle Pear.= See AMYL (Acetate).

=Oil of Jas′min.= _Syn._ OIL OF JESSAMINE; OLEUM JASMINI, O. J. VOLATILE, L. From the flowers of _Jasminum grandiflorum_ and _J. Fragrans_, carefully picked, by placing them in alternate layers with cotton wadding imbued with olive oil, in any suitable vessel, and renewing the flowers till the fixed oil becomes strongly odorous, and then distilling the wadding along with a little water. The volatile oils of hyacinths, jonquil, tuberose, violets, and most of the more delicate flowers, are obtained in the same way. Used in perfumery. From the East Indies.

=Oil of Ju′niper.= _Syn._ JUNIPERI OLEUM (B. P.), OLEUM JUNIPERI (Ph. L. E. & D.), O. È. BACCIS J., O. ESSENTIALE È. B. J., L. From either the wood, tops, or berries, preferably the last. The berries should be chosen fully grown, but still slightly green, and should be bruised before being placed in the still. In the Ph. L., English oil of juniper (O. JUNIPERI ANGLICUM) is ordered. Colourless, or very pale greenish-yellow; odour and taste, sweet and terebinthinate; rather viscid; soluble in rectified spirit; rendered opaque and resinous by exposure and age. It is reputed carminative and diaphoretic, and possesses powerful diuretic properties, Sp. gr. ·911 (English, ·8688; foreign, ·8834——Brande). _Prod._ Green berries, ·25%; ripe do. (one year old), 3/4 to 1% (fully).

_Pur._ It is frequently adulterated with oil of turpentine, a fraud readily discovered by the lessened density, viscidity, and solubility, in rectified spirit, of the oil.

_Obs._ Oil of juniper consists of two oils——one, white and most volatile, sp. gr. ·8393; the other, dark-coloured and less volatile, sp. gr. ·8784; together with some resin left in the retort.

=Oil, Krumholz.= _Syn._ OLEUM TEMPLINUM, L. From Hungarian balsam, a terebinthinate exudation from the _Pinus pumilio_, or mountain pine of Southern Europe. Fragrant; golden yellow; tastes oily, acidulous, and resinous.

=Oil of Lau′rel.= _Syn._ OIL OF SWEET BAY; OLEUM LAURI VOLATILE, O. L. ESSENTIALE L. From either the berries or leaves of _Laurus nobilis_ (Linn.), or sweet bay-tree. Pale yellow, clear, odorous, aromatic, stimulant, and narcotic. Sp. gr. ·871. _Prod._ From the leaves, 3/4 to 1% (fully).

=Oil of Lavender.= _Syn._ ESSENCE OF L.; LAVANDULÆ OLEUM (B. P.), OLEUM LAVANDULÆ (Ph. L.), O. L. VERÆ (Ph. E. & D.), O. L. SPICÆ, O. L. ESSENTIALE, O. L. FLORUM, L. The oil (OLEUM LAVANDULÆ ANGLICUM) distilled from the flowers of ‘_Lavandula vera_’ (Ph. L.). Very pale lemon-yellow; highly fragrant; taste, warm and not disagreeable; carminative, antispasmodic, and stimulant. Sp. gr. ·877 to ·905. According to Brande, the sp. gr. of the oil obtained from the flowers only is ·8960; that from the whole plant, ·9206. The lightest is esteemed the best. _Prod._ Flowers, 1-1/2 to 2% (nearly). The whole of the flowering herb is commonly distilled. According to Raybaud, the herb, after flowering (Sept.), yields the most oil.

_Pur._ Alcohol is the substance commonly used to adulterate this oil; but, occasionally, oil of bergamot is used for the same purpose. If the density is below ·87, there is reason to suspect adulteration. When pure——1. Sulphuric acid turns it reddish-brown, and the reaction is accompanied by strong inspissation.——2. It fulminates quickly and violently with iodine, and the thick syrupy residue possesses a pungent, acid, balsamic odour. The oils of the other labiate plants fulminate much less powerfully with iodine. The presence of alcohol weakens, but does not destroy, the action of this test, unless it is added in an equal volume, when only a lively effervescence and a disengagement of orange-coloured vapours are produced by the iodine, without fulmination.——3. Santaline is nearly insoluble in pure oil of lavender, and exerts no marked action on it, but is freely soluble in oil of lavender adulterated with alcohol or rectified spirit.

_Obs._ English oil of lavender possesses the purest fragrance; and of this, the variety known as “MITCHAM OIL OF LAVENDER,” from the place of its preparation, is esteemed the best. The foreign oil of lavender is inferior. This last is improved by rectification. See OIL OF SPIKE.

=Oil of Lem′ons.= _Syn._ ESSENCE OF L.; OLEUM LIMONIS (B. P.), OLEUM LIMONIS, O. LIMONUM (Ph. L. E. & D.). From the yellow portion of the rind, grated, placed in hair bags, and exposed to powerful pressure; also by distillation, but the product is then less agreeably fragrant and sweet, but keeps better. Nearly colourless; odour that of the fruit. Sp. gr. ·8752 to ·8785. Expressed oil, ·8517, distilled do., ·845, at 72° Fahr. (Ure.) _Prod._ 100 lemons yield, by expression, 1-3/4 to 2 oz. (nearly); by distillation 1-1/4 to 1-1/2.

_Pur._ Commonly adulterated with oil of turpentine, and occasionally with nut or poppy oil. These may be detected in the manner already explained. When pure, it is soluble in all proportions in absolute alcohol, but rectified spirit only dissolves 16% of it. It also boils at 148° Fahr., whereas oil of turpentine boils at 312°, and mixtures of the two at intermediate temperatures, depending on the proportions.

=Oil of Le′mon Grass.= _Syn._ ESSENCE OF L. G., INDIAN GRASS-OIL, OIL OF VERBENA. Probably from _Andropogon citratum_, the Indian lemon-grass. Pale yellow; powerfully fragrant. CITRONELLE OIL is also the product of this or of an allied species of _Andropogon_.

=Oil of Lemon Thyme.= _Syn._ OLEUM SERPYLLI, L.; HUILE DE TAIN, Fr. From the fresh flowering herb of _Thymus serpyllum_, the lemon or wild thyme of our hills and pastures. Very fragrant, used to scent soaps &c. Sp. gr. ·867. _Prod._ 100 lbs. yield 2-1/2 to 5-1/2 oz. of oil. When pure, it is scarcely affected by iodine, but solution of chromate of potassa acts on it with energy.

=Oil of Let′tuce.= _Syn._ OLEUM LACTUCÆ VIROSÆ, L. From _Lactusa virosa_ (Linn.), or strong-scented wild lettuce. Closely resembles the odorous matter of opium.

=Oil of Limes.= _Syn._ OLEUM LIMETTÆ, L. From the rind of the fruit of _Citrus limetta_, or lime, as oil of lemons, which it somewhat resembles. _Prod._ 100 limes yield 2-1/4 to 2-1/2 oz. of oil.

=Oil of Lov′age.= _Syn._ OLEUM LEVISTICI, L. From the leaves of fruit of _Levisticum officinale_, Lovage. Pale yellow, aromatic, carminative. _Prod._ Fresh herb, ·1% to ·15%.

=Oil of Mace.= _Syn._ OLEUM MACIDIS, O. M. ESSENTIALE, O. M. STILLATITIUM, L. From the arillus of _Myristica officinale_ (commercial mace). Nearly colourless; fragrant; lighter than water; closely resembles oil of nutmeg. Sp. gr. ·945. _Prod._ 4-1/2 to 9%.

=Oil of Marc-brandy.= _Syn._ FUSEL OIL OF M.-B., O. OF GRAPE SPIRIT. Obtained after the spirit (marc-brandy) has passed over during the distillation of the fermented residuum of expressed grapes. Limpid; odorous; acrid; offensive; soon turns yellow in the air; soluble in 1000 parts of water, and in all proportions in rectified spirit; 6 or 7 drops will spoil a hogshead of brandy. According to M. Balard, this oil is a mixture of potato oil and œnanthic ether.

=Oil of Mar′joram.= _Syn._ OIL OF SWEET M.; OLEUM MARJORANÆ, O. ORIQANI M. (Ph. E.), L. From the fresh flowering herb of _Origanum marjorana_, or sweet or knotted marjoram. Pale yellow; odorous; tonic; stimulant. Sp. gr. ·925 (·940——Baumé). _Prod._ ·33 to ·35%. See OIL OF ORIGANUM.

=Oil of Mea′dow-sweet.= _Syn._ OLEUM SPIRÆÆ ULMARIÆ, L. From the flowers or flowering tops of _Spiræa ulmaria_ (Linn.), or common meadow-sweet. This oil is a native hydride of salicyl. It is yellow, sweet-scented, and slightly soluble in water, which then strikes a deep violet colour with the persalts of iron. It boils at 385° Fahr. Sp. gr. 1·172. (See _below_.)

=Oil of Mea′dow-sweet (Facti′′tious).= This is prepared as follows:——Salicin, 1 part, is dissolved in distilled water, 10 parts, and being placed in a glass retort, bichromate of potassa (in powder), 1 part, is added, followed by oil of vitriol, 2-1/2 parts, previously diluted with 4 times its weight of water; a gentle heat is next applied to the retort, and after the first effervescence resulting from the mutual reaction of the ingredients is over, the heat is increased, and the mixture is distilled for the oil in the usual manner. The product is absolutely identical with the natural oil of meadow-sweet. (See _above_.)

=Oil of Mil′foil.= _Syn._ OLEUM MILLEFOLII, L. From the flowers of _Achillæa millefolium_ (Linn.), or yarrow. Blue. Sp. gr. ·852. _Prod._ 14 lbs. of the dried flowers yield 3 dr. of oil.

=Oils, Mixed (Essential).= _Syn._ OLEA MIXTA ESSENTIALIA. From the oils of bergamot and lemons, of each 1 oz.; oils of lavender and pimento, of each 1/2 oz. Used to scent ‘sal volatile drops,’ smelling-bottles, &c.

=Oil of Mus′tard (Volatile).= _Syn._ SULPHO-CYANIDE OF ALLYL; OLEUM SINAPIS NIGRÆ, O. S. ESSENTIALE, L. From the seeds of _Sinapis nigra_(Linn.), or black mustard, as oil of bitter almonds. Nearly colourless; intensely acrid, pungent, rubefacient, and vesicant; slightly soluble in water; boils at 289° Fahr. It contains sulphur. Sp. gr. 1·035 to 1·038; 1·015, at 68° Fahr. _Prod._ Av. ·6% (fully).

_Obs._ This oil, like that of bitter almonds, does not pre-exist in the seed, but is the result of the action of myronic acid on a peculiar substance, myrosin, in the presence of water. Oil of black mustard has been used as a stimulant or counter-irritant in palsy, &c.; and the distilled water, or a solution of the oil in water, is said to be an excellent and cleanly remedy for the itch.

=Oil of Myrrh.= _Syn._ OLEUM MYRRHÆ, O. M. ESSENTIALE, L. Colourless; thin; heavier than water; stimulant; smells strongly of the drug.

=Oil of Myr′tle (Volatile).= _Syn._ ESSENCE OF M.; OLEUM MYRTÆ ESSENTIALE, L. From the flowers and leaves of _Myrtus communis_. 100 lbs. of the fresh leaves yield 2-1/2 to 5 oz.

=Oil of Namur Grass.= See OIL OF GRASS (NAMUR).

=Oil of Narcis′sus.= _Syn._ ESSENCE OF JONQUIL; OLEUM NARCISSI, L. As OIL OF JASMINE. Delightfully odorous.

=Oil of Nero′li.= See OIL OF ORANGE FLOWERS.

=Oil of Nut′meg (Volatile).= _Syn._ OLEUM MYRISTICÆ (B. P., Ph. E.), O. M. MOSCHATÆ (Ph. D.), L. From the officinal nutmeg or kernel of the fruit of _Myristica moschata_. Nearly colourless; odour and flavour that of the fruit, but more powerful. By agitation with water, it is separated into two oils——one lighter, the other heavier, than water; the last is butyraceous. Sp. gr. ·948. _Prod._ 4-1/2 to 7%. It is reputed to make the hair grow, and to prevent baldness.

OIL OF ON’IONS. From the bulbs of _Allium cepa_, or common onion. Contains sulphur, and smells strongly of the herb.

=Oil of Or′ange.= _Syn._ ESSENCE OF O.; OLEUM AURANTII, O. AURANTIORUM, O. A. CORTICIS, L. From the yellow portion of the rind of either the Seville or sweet orange, preferably of the last; as oil of bergamot or lemons. Closely resembles oil of lemons, but is more agreeably fragrant. The expressed oil is very apt to become opaque, and deposit a stearopten, especially in cold weather, unless well kept from the air. Sp. gr. ·875. _Prod._ 100 fruits yield 4 to 5 oz. (See _below_.)

=Oil of Orange Berries.= _Syn._ OLEUM AURANTII BACCÆ, L. From the small unripe fruit of the orange-tree. Does not keep well. (See _below_.)

=Oil of Orange Flowers.= _Syn._ NEROLI, OIL OF N., ESSENCE OF N.; OLEUM NAPHÆ, O. AURANTII FLORUM, AURANTII OLEUM (Ph. E. and D.), L. From the flowers of either the bitter (Seville)or sweet orange (_Citrus vulgaris_ or _C. aurantium_), by distillation with water. That from the fruit is said to be preferred, but there does not appear any actual difference between the two. Very fluid; lighter than water, in which it is slightly soluble; it is delightfully aromatic and fragrant, but the odour differs slightly from that of the flowers. _Prod._ 100 lbs. of flowers gathered in May or December yield 3 to 6 oz. of oil; 6 cwt. of the fresh flowers yield 1 lb. of oil.

_Pur._ Neroli is commonly adulterated with alcohol or essence de petit grain, and generally with both of them. The presence of the first is easily determined (see _above_): that of the second can only be discovered by comparing the odour evolved during the evaporation of a drop of the suspected oil, placed on a piece of white paper, with a like drop of pure neroli similarly treated. (See _above_ and _below_.)

=Oil of Orange-leaf.= _Syn._ OLEUM AURANTII FOLII, L.; ESSENCE DE PETIT GRAIN, Fr. From the leaves of either the bitter or sweet orange; that from the first being preferred. Delightfully fragrant. Extensively used to adulterate oil of neroli, and is itself commonly sophisticated with both alcohol and oil of orange-berries. (See _above_.)

=Oil of Orig′anum.= _Syn._ OLEUM ORIGANI, O. O. ESSENTIALE, L. From the flowering herb of _Origanum vulgare_, or common or winter marjoram. Pale yellow colour; fragrant; acrid, pungent, and rubefacient. Sp. gr. ·927 (·940——Baumé). _Prod._ ·5% to ·75%. The dark-coloured oil of origanum of the shops is obtained from _Thymus vulgare_. The oil of origanum (Ph. E.) is oil of _Origanum marjorana_. See OILS OF MARJORAM, THYME, and LEMON THYME.

=Oil of Or′ris.= _Syn._ ESSENCE OF VIOLET; OLEUM IRIDIS, L. From the dried rhizomes of _Iris Florentina_, or Florentine orris-root. Fragrant. Sold for oil and essence of violets.

=Oil of Par′sley.= _Syn._ OLEUM PETROSELINI, L. From the fresh herb or dried fruit (seed) of _Apium petroselinum_, or garden parsley. Yellowish; smells strongly of the plant. It consists of two oils, separable by agitation with water, one of which is concrete, and melts at 80° Fahr.; the other, liquid. _Prod._ Herb, ·50 to 1% (nearly).

=Oil of Par′tridge-berry.= _Syn._ OIL OF WINTER-GREEN, METHYLO-SALYCILIC ETHER, SALICYLATE OF OXIDE OF METHYL; OLEUM GAUL-THERIÆ (Ph. U. S.), L. From the leaves or the whole plant of _Gaultheria procumbens_, a herb common in North America, and otherwise known by the names——Box-berry, chequer-berry, partridge-berry, mountain tea, winter-green, &c. Pale yellow, growing brown by exposure and age; aromatic; sweet; highly pungent; when diluted, agreeably fragrant; mixed with a dilute solution of potassa, it solidifies to a crystalline mass (salicylate of methyl and potassa), from which the oil may be again separated by the addition of an acid. It is the heaviest of all the essential oils. Sp. gr. 1·173. Boils at 412°, and, when purified, at 435° Fahr.

Oil of partridge-berry, dissolved in rectified spirit, is in common use in the United States of America as an antispasmodic, carminative, diuretic, emmenagogue, and stimulant; chiefly as an adjunct to mixtures, &c.; and also with the view of increasing the flow of milk during lactation. It is likewise extensively used in perfumery, and is an object of great interest to the organic chemist, on account of its peculiar constitution and reaction.

=Oil of Partridge-berry (Facti′′tious).= See SALICYLIC ACID.

=Oil, Pearl.= See AMYLE (Acetate of), and ESSENCE OF JARGONELLE PEAR.

=Oil of Pennyroy′al.= _Syn._ OLEUM PULEGII (Ph. L.), O. MENTHÆ P. (B. P., Ph. E. & D.), O. P. ESSENTIALE, L. From the flowering herb of _Mentha Pulegium_, or the common pennyroyal of our gardens. Pale yellow, growing reddish yellow by age and exposure; antispasmodic, carminative, and emmenagogue. Boils at 395° Fahr. Sp. gr. ·925 to ·931. _Prod._ 3/4 to 1%. (See _below_.)

=Oil of Pennyroyal (American).= _Syn._ OLEUM HEDEOMÆ (Ph. U. S.), L. From _Hedeoma pulegioides_, as the last. Light yellow; closely resembles oil of pennyroyal, for which it passes in the U. S. Sp. gr. ·945 to ·948.

=Oil of Pepper.= _Syn._ OIL OF BLACK P.; OLEUM PIPERIS, O. P. NIGRI, L. From bruised black pepper (_Piper nigrum_). Colourless, turning yellow; odorous; pungent; not so hot as the spice. Sp. gr. ·9932. _Prod._ 1·25% to 1·5%. White pepper (of commerce), 1% (barely).

=Oil of Pep′permint.= _Syn._ OLEUM MENTHÆ PIPERITÆ (B. P., Ph. L., E., & D.), O. ESSENTIALÆ M. PIPERITIDIS, L. From the fresh flowering herb of _Mentha piperita_, or garden peppermint. Nearly colourless, or at most a very pale greenish yellow; powerfully odorous; tastes pungent, at the same time imparting a sensation of coldness to the tongue and palate. Boils at 365° Fahr. Sp. gr. ·902 to ·905. _Prod._ Fresh flowering herb, ·25% to ·4%; dried do., 1% to 1·25% (fully). In a warm dry season, 5 lbs. of the fresh flowering herb yield 1 oz. of oil; in a wet and unfavorable one, 11 lb. yield barely the same quality.

_Pur._ The oil of commerce usually contains fully a third part of rectified spirit, and is also frequently adulterated with the oils of rosemary, spearmint, and turpentine. When pure——1. It is soluble in its own weight of rectified spirit.——2. Mixed with 1-4th its volume of nitric acid, a rich purple-red colour is developed.——3. Chromate of potash, in solution, turns it of a deep reddish-brown colour, and converts it into a soft coagulum, which assumes a flaky form when divided with a glass rod, whilst the solution of the salt loses its yellow colour or becomes greenish yellow.——4. With iodine it forms a homogeneous mass, without fulmination. If it explodes with iodine, it contains turpentine. The yellowish, resinous oil, sold under the name of ‘American’ or ‘crude oil of peppermint,’ consists chiefly of oil of turpentine, and on evaporation leaves a residuum of pine resin.

_Obs._ English oil of peppermint is the best, a fact clearly shown by its price in the market being so greatly above that of the imported oil. The oil distilled at Mitcham, in Surrey (Mitcham oil of peppermint), is the most esteemed. It has usually a very pale greenish colour, which is often imitated by steeping a leaf or two of green mint or parsley in the oil. Old dark-coloured oils are commonly bleached by exposure to the light, to the destruction of a portion of their other properties.

According to a recent and valuable report upon those articles in the Paris Exhibition of 1878, more particularly interesting to the pharmacist, the chemical manufacturer, the perfumer, &c., which lately appeared in the ‘Pharmaceutical Journal,’ the above statement is open to question. Of late years it seems that a considerable industry has sprung up at Arzin in the Department du Nord, in France, where large quantities of libiate plants are cultivated, and subsequently submitted to distillation.

An acre of land generally yields every year from 3 to 4 tons of the peppermint plant; and from 500 parts of this, one part of essential oil is usually obtained, which it is alleged by M. Hanart, the distiller of the oil in question, after being carefully bottled and kept for some years, successfully rivals the English oil both in quality and price.

Of late years an essential oil of peppermint manufactured by Messrs Holchkiss, of New York, has lately come into considerable demand.

This, which is said to be a very pure article, differs from the other peppermint oils in becoming thick when first mixed with spirit of wine. After a short time, however, the mixture clears and becomes perfectly bright.

Oil of peppermint is stimulant, antispasmodic, and carminative, and has always been a favourite remedy in flatulence, nausea, vomiting, loss of appetite, cramp of the stomach, colic, griping pains, diarrhœa, the early stage of cholera, &c.——_Dose_, 1 to 3 drops, on sugar.

=Oil of Petro′leum.= See NAPHTHA, OILS (Mineral), PETROLEUM, &c.

=Oil of Pim′ento.= _Syn._ OIL OF ALLSPICE; OLEUM PIMENTÆ (B. P., Ph. L., E., & D.), L. From the bruised fruit of _Eugenia pimenta_, allspice, or Jamaica pepper. Pale yellow, growing reddish brown by age; odour, a combination of cloves and cassia; taste pungent. Sp. gr. 1·021. _Prod._ 5% to 8%.

_Obs._ Oil of pimento contains two oils similar to those found in clove oil. When pure, nitric acid turns it red, with active effervescence and the assumption of a rusty brown colour. It combines with the salifiable bases in a nearly similar manner to oil of cloves. It is much used in perfumery, especially in hair cosmetics.

=Oil of Pim′pernel.= _Syn._ OLEUM PIMPINELLÆ, L. From the root of _Sanguisorba officinalis_, or pimpernel. Blue; carminative.

=Oil, Pine-ap′ple.= This artificial essential oil dates its commercial importance from the Great Exhibition of 1851. It is essentially butyric ether, and may be regarded as simply the crude form of that substance. On the large scale it is prepared by saponifying butter or crude butyric acid with a strong lye of caustic potassa, and dissolving the resulting soap in the smallest possible quantity of hot alcohol; to the solution is added a mixture of alcohol and oil of vitriol in excess, and the whole is then submitted to distillation as long as the product has an aromatic fruity odour; the product is rectified from dried chloride of calcium and a little litharge. Dissolved in rectified spirit it is much used as a flavouring substance by confectioners and liquoristes. See ETHER (Butyric) and ESSENCE OF PINE-APPLE, &c.

=Oil of Pota′to Spirit.= See FUSEL OIL.

=Oil of Ravensa′ra.= _Syn._ OLEUM RAVENSARÆ, L. From the roots of _Ravensara aromatica_. Chiefly used to adulterate oil of cloves, which it somewhat resembles.

=Oil of Rho′dium.= _Syn._ OLEUM RHODII, L. Said to be derived from the wood of a species of _Rhodoriza_. Very fluid and limpid; pale yellow; soon darkens by age and exposure; tastes bitter and aromatic; has a modified odour of roses. Chiefly used as a substitute for otto of roses in cheap perfumery, and to adulterate it. Oil of sandal-wood is frequently sold for it. _Prod._ 1% to 16%. See OIL OF ROSES (_below_).

=Oil of Ro′′ses.= _Syn._ OLEUM ROSÆ, L. _Prep._ 1. From the petals of _Rosa sempervirens_ (Linn.), or the musk rose, as oil of cloves, observing to keep the water in the worm-tub at 85° Fahr., and afterwards subjecting the water in the receiver to refrigeration. Resembles otto of roses, of which it is merely a variety. _Prod._ 1/20 to 1/16 of 1%.

2. (ATTAR OF ROSES, OTTO OF R.; OLEUM ROSÆ——Ph. E.) From the petals of _Rosa centifolia_ and _Rosa sempervirens_ (damask and musk rose), principally the first, by saturating the water, by returning it repeatedly on fresh flowers, and then exposing it to a low temperature. In the East Indies it is obtained by stratifying gingelly seeds in alternate layers with rose petals, for some days, and repeating the arrangement with fresh roses till the seeds are saturated, when the oil is expressed and distilled along with water. In the neighbourhood of Mecca the rose leaves are macerated in salt-and-water for 2 or 3 days, and then distilled, the water being received in separate receivers at different parts of the process. The water is afterwards exposed in porous earthenware vessels, tied over with linen, in trenches dug in the earth, and over which moistened straw is thrown, when in a short time the otto separates and floats on the surface.

_Prop., &c._ Colourless, or nearly so; odour intense, penetrating, and diffusive, and in a concentrated state far from pleasant, but when dilute very agreeable; taste, bland and sweetish; when pure, it congeals at 80°, and does not remelt until heated to fully 85° Fahr.; 1000 parts of alcohol of ·806 dissolve only 7 parts of otto at 57° Fahr., and only 33 parts at 72°. Sp. gr. ·832 at 90°, to water 1·000 at 60° Fahr. _Prod._ 100 lbs. of roses yield 2 to 3 dr.

_Pur._ Otto of roses is frequently adulterated with the oils of rhodium, sandal-wood, and geranium, and with camphor; and occasionally with spermaceti, to give the spurious compound the usual crystalline appearance. The following are reliable tests:——1. Pure otto has a bland, sweet taste; if it is bitter, it contains oil of rhodium or sandal-wood; if it is pungent, or ‘bites,’ the palate, it contains either oil of geranium or camphor, and probably both; if it imparts an unctuous sensation, it contains spermaceti.——2. Exposed for some hours to the fumes of a small quantity of iodide under a bell-glass in the cold, pure otto remains white, and continues so when exposed to the air; an adulterated sample, on the contrary, becomes yellow or brown, and afterwards, on exposure to the air, continues to darken in colour, until it becomes of a deep brown, or even perfectly black, according to the quantity of foreign oil present. A single drop may be thus tested.——3. (Guibourt.) One or two drops of the suspected oil are put into a watch-glass; the same number of drops of concentrated sulphuric acid are added, and the two fluids are mixed with a glass-rod. All the oils are rendered more or less brown by this proceeding; but, otto of roses retains the purity of its odour——oil of geranium acquires a strong and disagreeable odour, which is perfectly characteristic——the odour of the oil of rhodium is increased, and becomes somewhat unctuous, and, in general, it acquires an odour distinctly like that of cubebs.

=Oil of Rose′mary.= _Syn._ ROSMARINI OLEUM (B. P.), OLEUM ANTHOS, O. RORISMARINI, O. ROSMARINI (Ph. L. E. & D.), O. RORISMARINI ESSENTIALÆ, L. From the flowering tops of _Rosmarinus officinalis_. In the Ph. L. English oil of rosemary (O. ROSMARINI, ANGLICUM) is ordered, as it is superior to that from abroad. Colourless; strongly fragrant, but scarcely agreeable unless compounded; carminative and stimulant. Boils at 365° Fahr. Sp. gr. ·910; recent,·897; rectified, ·8887. _Prod._ 3/4 to 1% (nearly).

_Pur., &c._ It is frequently adulterated with oil of turpentine. When pure it dissolves in all proportions in spirit of ·830. By age it deposits a crystalline stearoptene, and acquires a terebinthinate odour. It is chiefly used as a stimulant in liniments, hair oil, pomatums, &c.

=Oil of Rose′wort.= _Syn._ OIL OF ROSE-ROOT; OLEUM RHODIOLÆ, L. From the roots of _Rhodiola rosea_. Yellowish; odour resembles that of oil of rhodium, for which it is often sold, as well as the distilled water for rose water. 1-1/2 lb. yields about 1 dr.

=Oil of Rue.= _Syn._ RUTÆ OLEUM (B. P.), OLEUM RUTÆ (Ph. L. & E.), L. The “oil distilled from the fresh herb of _Ruta graveolens_” (B. P.), or common rue. Pale yellow, turning brown by age, and depositing a brownish, resinous sediment; congeals at about 40° Fahr.; acrid, bitter; odour that of the plant; stimulant, antispasmodic, and emmenagogue. Sp. gr. ·909 to ·911. _Prod._ 1/4 to 1%(nearly). According to Raybaud, the recent dried seeds yield fully four times as much oil as the flowering herb.

_Pur._ Nearly always adulterated. When pure——1. It forms a clear solution with rectified spirit.——2. It does not form a camphor with gaseous hydrochloric acid.——3. Iodine dissolves in it slowly, without any apparent reaction, beyond a darkening and a slight increase of viscidity.——4. It is unaffected by a solution of chromate of potassa.——5. Nitric acid very slowly changes it into a greenish-yellow liquid balsam.——6. If it forms a reddish-brown solution with liquor of potassa and a still darker one with oil of vitriol, or if it fulminates with iodine, it is adulterated with the oil of some labiate plant.——7. It is more soluble in both rectified spirit and water than any of the oils used to adulterate it.

=Oil of Saf′fron.= _Syn._ OLEUM CROCI, L. From the pistils of _Crocus sativus_ (saffron). Yellow; heavier than water; acrid, pungent, and narcotic; decomposed by exposure to light and age, with the formation of a white solid matter, which is lighter than water.

=Oil of Sage.= _Syn._ OLEUM SALVIÆ, L. From the herbaceous portion of _Salvia officinalis_, or common sage.

=Oil of San′dal-wood.= _Syn._ OLEUM SANTALI, O. S. ALBI, L. From the wood of _Santalum album_, or sandal-tree, and preferably from that of Malabar. It has an odour somewhat resembling that of oil of rhodium, for which it is commonly used; also used to adulterate otto of roses. _Prod._ 9 lbs. yield 1 oz.; 100 lbs. yield 5 oz. (Raybaud).

=Oil of Sarsaparil′la.= _Syn._ OLEUM SARZÆ, L. From the root bark, distilled along with salt-and-water. Acrid; odour and flavour same as the root.

=Oil of Sas′safras.= _Syn._ VOLATILE OIL OF S.; OLEUM SASSAFRAS (Ph. E.), O. LAURI S., O. S. OFFICINALIS, L. From bruised sassafras chips, the sliced root of _Sassafras officinale_, as oil of cloves. Pale yellow; highly odorous; hot, pungent, rubefacient, and stimulant; reputed alterative, sudorific, and diuretic, and, as such, occasionally given in rheumatism, cutaneous affections, &c. Sp. gr. 1·094 to 1·096. _Prod._ 1-1/2 to 2% (fully).

_Pur., &c._——1. If the density is lower than 1·094, it is adulterated.——2. Nitric acid acts on this oil, at first slowly, merely turning it of an orange-red, but afterwards with violence, and a reddish-brown resin is formed.——3. Mixed with about one half its weight of sulphuric acid, a green colour is at first developed, which, by heat, is changed to a blood red. A large quantity of sulphuric acid acts at once violently, white fumes are given off, and mere charcoal is left.——4. With iodine it forms a permanently clear solution, or at least one that remains so for some time.——5. By agitation with water, it separates into two oils——one lighter, the other heavier, than that fluid.

=Oil of Sav′ine.= _Syn._ OLEUM SABINÆ (B. P.), OLEUM JUNIPERI SABINÆ, O. SABINÆ (Ph. E. & D.), L. From the fresh tops or leaves of _Juniperus sabina_, or common savin. Pale yellow; limpid; acrid, pungent, and stimulant. It possesses the general properties of the plant in a highly exalted degree. Sp. gr. ·915. _Prod._ Fresh herb, 1·25% to 1·5%; dried do. (recent), 2-1/2% to 3%. _Dose_, 2 to 6 drops; as an anthelmintic, diaphoretic, and emmenagogue. Its use must be carefully avoided during pregnancy or disease of the abdominal viscera.

_Pur., &c._ It is less frequently adulterated than the other volatile oils. Its high sp. gr. and free solubility in rectified spirit offer the means of detecting the presence of either oil of turpentine or alcohol, the substances occasionally added to it. A mixture of equal parts of oil of savin and oil of vitriol, by distillation from milk of lime, furnishes an oil apparently identical with oil of thyme. (Winckler.)

=Oil of Sen′na.= _Syn._ OLEUM SENNÆ VOLATILE, L. Possesses the nauseous odour and flavour of the leaves, and, as well as the distilled water, is purgative.

=Oil of Spear′mint.= _Syn._ ENGLISH OIL OF SPEARMINT (B. P.), OIL OF MINT, OIL OF GREEN M.; MENTHÆ VIRIDIS OLEUM (B. P.); OLEUM MENTHÆ VIRIDIS (Ph. L., E., & D.), O. M. SATIVÆ, O. ESSENTIALE MENTHÆ S., L. From the fresh flowering herb of _Mentha viridis_ (Linn.) or garden spearmint. Pale yellow; reddened by age; odour and general properties resemble those of oil of peppermint, but it is less grateful. It boils at 320° Fahr. Sp. gr. ·915 (·9394, Brande). _Prod._ ·2% to ·25%. Its common adulterants are alcohol and oil of turpentine.

=Oil of Spike (True).= _Syn._ FOREIGN OIL OF LAVENDER; OLEUM SPICÆ, O. S. VERUM, O. STÆCHADIS, O. LAVANDULÆ S., L.: HUILE D’ASPIC, Fr. Chiefly from _Lavandula spica_ and _L. stæchas_, or French and Alpine lavenders. It differs from English oil of lavender by its darker green colour and inferior odour. From France. Used by artists to mix their colours in, and to make varnishes. Oil of turpentine scented with lavender is commonly sold for it. _Prod._ From _L. spica_ (fresh), 3/4 to 1-1/2%; _L. stæchas_ (dried), 3/4 to 1% (fully).

=Oil of Spike′nard.= _Syn._ OLEUM NARDI, L. The precious oil mentioned under this name in Scripture is supposed to have been derived from _Andropogon Iwaracusa_. The commercial oil of geranium (see _above_) is also called by this name.

=Oil of Spring Grass.= _Syn._ OLEUM ANTHOXANTHI ODORATI, L. From _Anthoxanthum odoratum_, or sweet-scented vernal grass. It is this oil that gives the very agreeable odour to new hay.

=Oil of Star-an′ise.= _Syn._ BADIAN OIL; OLEUM BADIANI, O. ANISI STELLATI, L. From the capsules of _Illicium anisatum_, or star-anise. It continues liquid at 35-1/2° Fahr. This, and its weaker reaction with iodine, distinguish it from the preceding compound, which it is commonly used to adulterate. _Prod._ 2% (fully).

=Oil of Sweet Fen′nel.= See OIL OF FENNEL.

=Oil of Sweet Flag.= _Syn._ OLEUM ACORI, O. A. AROMATICA, L. From the rhizomes or roots of _Acorus calamus_ (Linn.), or sweet flag. Yellow; agreeably fragrant. Used to scent snuff, aromatic vinegar, &c. _Prod._ Fresh rhizomes, 3/4 to 1%; dried (recent), 1 to 1·25%.

=Oil of Tan′sy.= _Syn._ OLEUM TANACETI, L. From the flowering herb of _Tanacetum vulgare_ (Linn.), or tansy. Pale greenish yellow; very odorous; bitter; aromatic. Sp. gr. ·946 to ·950. _Prod._ Fresh, ·25% to ·5%; dried (recent), 3/4 to 1%(fully).

=Oil of Thyme.= _Syn._ OLEUM THYMI; OIL OF ORIGANUM; OLEUM ORIGANI (of the shops). From the flowering herb of _Thymus vulgaris_ (Linn.), or garden thyme. Nearly colourless; the imparted oil has a reddish colour, which it loses by rectification; very fragrant; acrid; hot tasted, stimulant, and rubefacient; boils at 354° Fahr. Sp. gr. ·867 to ·875. _Prod._ ·5% to ·75%.

_Obs._ This is the dark-coloured ‘OIL OF ORIGANUM’ of the shops. It is frequently adulterated with oil of turpentine. It is occasionally used in toothache and in stimulating liniments; but its chief consumption is in perfumery, more particularly for hair oils, pomatums, and hair-washes, as it is reputed to make the hair grow and to prevent baldness.

=Oil of Tobac′co (Volatile).= From the leaves of _Nicotiana tabacum_ (Linn.), or the tobacco plant. Concrete.

=Oil of Turpentine.= _Syn._ SPIRIT OF T., ESSENCE OF T., TURPS, CAMPHENE, CAMPHINE; TEREBINTHINÆ OLEUM (B. P.), SPIRITUS TEREBINTHINÆ, ESSENTIA T., OLEUM TEREBINTHINÆ (Ph. L. & D.), O. T. PURIFICATUM (Ph. E.), L. The oil of turpentine of commerce is obtained by distilling strained American turpentine along with water. The residuum in the still is ‘resin’ or ‘rosin.’ The product in oil varies from 14% to 16%. The colleges order it to be rectified before being employed for medicinal purposes. This is effected by redistilling it along with 3 or 4 times its volume of water, observing not to draw over quite the whole. The portion remaining in the retort (balsam of turpentine) is viscid and resinous. A better plan is to well agitate it with an equal measure of solution of potassa or milk of lime before rectifying it. This is the plan adopted for the camphine used for lamps. By agitating crude oil of turpentine with about 5% of sulphuric acid, diluted with twice its weight of water, and after repose and decantation rectifying it from 5 or 6 times its volume of the strongest lime water, a very pure and nearly scentless oil may be obtained. Dr Nimmo recommends oil of turpentine to be purified by agitation with 1/8th part of rectified spirit, after repose to decant the spirit, and to repeat the process 3 or 4 times. The product retains, however, fully 1/5th part of spirit in solution, and hence this method is objectionable, except for medicinal purposes, for which, according to Dr Garrod, it is better than the oil purified by rectification. The sweet spirits of turpentine (SPIRITUS TEREBINTHINÆ DULCIS), vended of late years in the shops, is simply the common oil which has been agitated with, and rectified from, somewhat dilute sulphuric acid.

_Prop._ Pure oil of turpentine is colourless; limpid; very mobile; neutral to test-paper; has an odour neither powerful nor disagreeable when recently prepared, but becoming so by exposure to the air; dissolves 1/5th part of alcohol of ·830; is soluble in 6 parts of ether and in 7-1/2 parts of rectified spirit; hot strong alcohol dissolves it freely, but the greater part separates in globules as the liquid cools. Oil of vitriol chars it, and strong nitric acid attacks it violently, even with flame. It congeals at 14°, and boils at 312° Fahr. Sp. gr. ·867; that of the oil of the shops varies from ·872 to ·878. It possesses a very high refractive power. At 72° it absorbs 163 times its volume of hydrochloric-acid gas (if kept cool), and in 24 hours from 26% to 47% of crystals (KIND’S CAMPHOR) separate. These have a camphoraceous odour, and, after being washed with water, and sublimed along with some dry chalk, lime, or charcoal, assume the form of a white, translucent, flexible, crystalline mass, which is volatile, soluble in alcohol, and possesses a considerable resemblance to camphor. A nearly similar substance is produced by the action of oxygen gas on oil of turpentine.

_Uses, &c._ Oil of turpentine is extensively used in the manufacture of varnishes and paints. Under the name of ‘camphine’ it is occasionally employed for burning in lamps. For the last purpose it must be newly rectified and preserved from the air. By exposure it rapidly absorbs oxygen, resin is formed, its density increases, and it gives a dull fuliginous flame. In medicine it is employed as a diaphoretic, stimulant, vermifuge, &c.——_Dose_, 6 to 30 or 40 drops; in rheumatism, hemicrania, &c., 1 fl. dr. every four hours, in combination with bark or capsicum; in tapeworm, 3 fl. dr. to 1 fl. oz., either alone or combined with a little syrup of orange peel, every 8 hours, until the worm is expelled. The common symptoms of large doses of this oil are dizziness and a species of temporary intoxication, and occasionally nausea and sickness, which subside after two or three alvine evacuations, leaving no other effect, when the oil is pure, than a certain degree of languor for a few hours. In tapeworm a little castor-oil may be advantageously combined with the second and subsequent doses. Oil of turpentine imparts a violent odour to the urine. To prevent loss by evaporation and resinification, this oil should be kept in tin cans or glass bottles. For store vessels, closely covered tin cisterns are the best. To _prevent accidents_ it is proper to caution the operator of the extremely penetrating and inflammable nature of the vapour of this oil, even in the cold. During the process of its distillation, without the greatest precautions are taken, an explosion is almost inevitable.

=Oil of Vale′′rian.= _Syn._ OLEUM VALERIANÆ (Ph. Bor.), L. From the root of _Valeriana officinalis_ (Linn.), or wild valerian. Yellowish; viscid; lighter than water; smells strongly of the plant. By exposure to the air it is partly converted into valerianic acid, and more readily so under the influence of an alkali. In its usual form it consists of valerol, a neutral oily body; borneene, a volatile liquid hydrocarbon; and valerianic acid. It is powerfully antispasmodic, emmenagogue, tonic, and stimulant, and, in large doses, narcotic.——_Dose_, 2 to 6 drops; in epilepsy, hysteria, hemicrania, hypochondriasis, low fevers, &c. _Prod._ 1-1/4% to 2% (nearly).

=Oil of Ver′bena.= _Syn_. OLEUM VERBENÆ, L. From the fresh flowering herb of _Verbena odorata_. _Prod._ 2% to 5%. The ‘OIL OF VERBENA’ of the shops is imported from India, and is obtained from _Andropogon citratum_. See OIL OF LEMON GRASS.

=Oil of Wine.= SYN. HEAVY OIL OF WINE, ETHEREAL OIL, OILY ETHEREAL LIQUOR, SULPHATE OF ETHER AND ETHEROLE; OLEUM ÆTHEREUM (Ph. L.), OLEUM VINI, LIQUOR ÆTHEREUS OLEOSUS, L. This is an artificial production which, for convenience, may be included under this head.

1. (Ph. L.) Rectified spirit, 2 pints, and sulphuric acid, 36 fl. oz., are cautiously mixed together in a glass retort, and submitted to distillation until a black froth appears, when the retort is immediately removed from the fire (sand heat); the lighter, supernatant, liquor is next separated from the fluid in the receiver, and exposed to the air for 24 hours; it is then agitated with a mixture of solution of potassa and water, of each 1 fl. oz., or q. s., and, when, sufficiently washed, is, lastly, separated from the aqueous liquid from which it has subsided. The formula of the Ph. L. 1836 is nearly similar.

2. (Ph. D.) Rectified spirit and oil of vitriol (commercial), of each 1-1/2 pint; as the last, employing a Liebig’s condenser, and a capsule for the exposure to the air; the oil is then transferred to a moistened paper filter, and washed with a little cold water, to remove any adhering acid.

3. (Ph. D. 1826.) From the residuum in the retort after the process of preparing ether, distilled to one half, by a moderate heat, and the oil treated as before.

4. From rectified spirit (sp. gr. ·833), 2 parts; oil of vitriol, 5 parts; mix and distil, as before; wash the product with distilled water, and free it from adhering water and undecomposed alcohol by exposure in the vacuum of an air-pump, between two open capsules, the one containing fragments of solid potassa, and the other concentrated sulphuric acid. Pure.

5. By distilling a mixture of ether and oil of vitriol, and treating the product as before.

6. By the destructive distillation of dry sulphovinate of calcium; the product is freed from alcohol, &c., by washing it. This process yields the largest product.

_Prop., &c._ An oily liquid, nearly colourless, neutral, with an aromatic taste, and an odour resembling that of oil of peppermint. It is insoluble in water, but freely soluble in both alcohol and ether; boiling water converts it into sulphovinic acid, and a volatile liquid called light or sweet oil of wine; with an alkaline solution, this effect is produced with even greater facility. Sp. gr. 1·05 (Hennel & Ph. L.); 1·13 (Serullas). Boils at 540° Fahr. “Dropped into water, it sinks, the form of the globule being preserved.” (Ph. L.) _Prod._ 1·25 to 1·5%; 33 lbs. of rectified spirit, and 64 lbs. of oil of vitriol, yield 17 oz. of this oil (Hennel).

_Uses._ Oil of wine is reputed anodyne, but is only used in the preparation of other compounds. See SPIRIT OF ETHER (Compound), &c.

=Oil of Wine (Light).= _Syn._ SWEET OIL OF WINE. See ETHERIN, ETHEROLE, and _above_.

=Oil, Wood (of India).= From the _Chloroxylon Swietenia_ (De Cand.), the tree which yields the satin-wood of the cabinet-makers. Another wood oil (GŪRJUN BALSAM) is obtained by incision from various species of _Dipterocarpus_. This balsam yields about 38% of a volatile oil by distillation, which in its general properties closely resembles OIL OF COPAIBA. (O’Shaughnessey.)

=Oil of Worm′seed.= _Syn._ OLEUM CHENOPODII (Ph. U. S.), L. From the seeds of _Chenopodium anthelminticum_, or Jerusalem oak (American wormseed). Light yellow, or greenish; powerfully anthelmintic. Sp. gr. ·908.——_Dose._ For an adult, 25 to 30 drops, in sugar, honey, or milk, night and morning, for 3 or 4 days, followed by a good dose of castor oil, or some other suitable purgative.

=Oil of Worm′wood.= _Syn._ OLEUM ABSINTHII, L. From the herbaceous portion of _Artemisia absinthium_, or common wormwood; green or brownish-green; odorous; acrid; bitter; stomachic. Sp. gr. ·9703 (Brisson); ·9720 (Pereira); ·9725 (Brande). _Prod._ Fresh herb (picked), 1/4 to 1/3%, dry herb (a year old), 1/2% (fully); do. (recent), 3/4 to 1% (fully).

_Pur._ That of the shops is nearly always either adulterated or partly spoiled by age; hence the discrepancies in the densities given for this oil by different authorities. A specimen of this oil distilled by Mr Cooley from the green plant had the sp. gr. ·9712; but after being kept for 12 months, it had increased to ·9718. Nitric acid of 1·25 colours the pure oil first green, then blue, and, lastly, brown. The positive character of these reactions is in direct proportion to the purity and freshness of the sample.

=OILY EMUL′SION.= See LINCTUS (Emollient).

=OILY ETHE′′REAL LIQ′UOR.= See OIL OF WINE (_above_).

=OINT′MENT.= _Syn._ UNGUENTUM, L. Any soft, fatty substance applied to the skin by inunction. The term is now commonly restricted to those which are employed in medicine.

Ointments (unguenta) differ from ‘cerates’ chiefly in their consistence, and in wax not being a constant or essential constituent; and they are made and used in a nearly similar manner to that class of preparations. Their proper degree of solidity is that of good butter, at the ordinary temperature of the atmosphere. When the active ingredients are pulverulent substances, nothing can be more suitable to form the body of the ointment than good fresh lard, free from salt; but when they are fluid or semi-fluid, prepared suet, or a mixture of suet and lard, will be necessary to give a due consistence to the compound. In some instances wax is ordered for this purpose. Another excellent ‘vehicle’ for the more active ingredients is a simple ointment, formed by melting together 1 part of pure white wax with about 4 parts of olive oil. The use of the last excludes the possibility of the irritation sometimes occasioned by the accession of rancidity, when inferior lard is employed. In a few cases butter is employed to form the body of the ointment.

Some ointments are made from recent vegetable substances by infusion or coction, in the manner adopted for medicated oils. See OILS, MEDICATED.

The precautions to be used in the choice of lard are noticed in the article devoted to this substance. Lard is included in the Materia Medica of the London College. In the last Ph. D. lard for medicinal use (ADEPS SUILLUS PRÆPARATUS——Ph. D.) is ordered to be prepared by melting it in twice its weight of boiling water, stirring it constantly for some time, then setting the mixture aside to cool; and, lastly, separating the fat when it has solidified.

Ointments are best preserved by keeping them in salt-glazed earthen or stoneware jars, covered with tin foil, in a cool situation.

The accession of rancidity in ointments and other unctuous preparations may be greatly retarded, if not wholly prevented, by previously dissolving in the fat about 2% of gum-benzoin, in fine powder, or rather less quantity of benzoic acid by the aid of heat. This addition renders the ointment peculiarly soothing to irritable or highly sensitive skins. Poplar buds act in a similar manner.

⁂ The formulæ for all the more useful and generally employed ointments are given below. Those not included in the list may be prepared of the proper strength for all ordinary purposes, by combining about 12 to 15 times the medium dose of the particular medicinal with 1 oz. of lard or simple ointment. For substances which possess little activity, 1/2 to 1 dr. per oz., or even more, may be taken. See CERATE, FAT, &c.

=Ointment of Ac′etate of Lead.= _Syn._ UNGUENTUM PLUMBI ACETATIS (B. P., Ph. E. & D.), L. _Prep._ 1. (Ph. E.) Acetate of lead, in fine powder, 1 oz.; simple ointment, 20 oz.; mix them thoroughly (by trituration).

2. (Ph. D.) Ointment of white wax, 1 lb.; melt by a gentle heat, then add, gradually, of acetate of lead, in very fine powder, 1 oz., and stir the mixture until it concretes.

3. (B. P.) Acetate of lead, in fine powder, 12 gr.; benzoated lard, 1 oz.; mix.

_Obs._ A useful, cooling, astringent, and desiccative ointment. For the formula of Ph. L., see CERATE.

=Ointment, Ace′tic.= See OINTMENT, VINEGAR.

=Ointment of Ac′onite.= _Syn._ UNGUENTUM ACONITI, L. _Prep._ 1. (Dr Turnbull.) Alcoholic extract of aconite, 1 part; lard, 2 parts; carefully triturated together. In neuralgia, &c.

2. (Ammoniated; UNGUENTUM ACONITI AMMONIATUM——Turnbull.) Ammoniated extract of aconite, 1 part; lard, 3 parts. In neuralgia, paralysis, old rheumatic affections, &c. The use of the above preparations of aconite requires the greatest caution. They are intended as substitutes for OINTMENT OF ACONITINE, a still more dangerous preparation.

=Ointment of Acon′itine.= _Syn._ UNGUENTUM ACONITINÆ, L. _Prep._ 1. (Dr Garrod.) Pure aconitine, 1 gr.; lard, 1 dr.; mix by careful trituration.

2. (Dr Turnbull.) Aconitine, 2 gr.; rectified spirit, 6 or 7 drops; triturate together, then add of lard, 1 dr., and mix well.

3. (B. P.) Aconitia (aconitine), 8 gr.; rectified spirit, 1/2 dr.; dissolve and add lard, 1 oz.; mix.

_Use, &c._ As a topical benumber in neuralgic affections, rheumatic pains, &c. Its application generally occasions considerable tingling, and sometimes redness of the part to which it is applied, followed by temporary loss of sensation in the skin and the cessation of the pain. For slight cases Dr Paris formerly employed only 1 gr. to the oz. Owing to the intensely poisonous nature of aconitine, this ointment must be both prepared and used with great caution, and must never be applied to an abraded surface. It is seldom employed, owing to its extreme costliness. See ACONITIA, and _above_.

=Ointment, Ague.= See OINTMENT, ANTIPERIODIC.

=Ointment, Albinolo’s.= See PATENT MEDICINES.

=Ointment, Alkaline.= _Syn._ UNGUENTUM ALKALINUM, L. _Prep._ 1. (Biett.) Carbonate of soda, 2 dr.; fresh-slaked lime, 1 dr.; powdered opium, 2 gr.; lard, 2 oz.; mix by trituration. In prurigo, ringworm, and some other cutaneous affections.

2. (Cazenave.) Carbonate of potassa, 1 dr.; lard, 1 oz. In psoriasis, lepra, and scorbutic eruptions.

3. (Devergie.)——_a._ From carbonate (not sesquicarbonate) of soda, 10 to 15 gr.; lard, 1 oz. In lichen.

_b._ From carbonate of soda, 20 to 30 gr.; lard, 1 oz. In ichthyosis, lepra, psoriasis, and some other scaly skin diseases.

_c._ From carbonate of soda, 1/2 to 1 dr.; lard, 1 oz. In porrigo favosa, especially when occurring in adults.

4. (Soubeiran.) Carbonate of soda, 1 to 2 dr.; wine of opium, 1 fl. dr.; lard, 1 oz. In any of the above affections, when there is much pain or irritation.

_Obs._ Carbonate of potassa is thought to be preferable to carbonate of soda, when the above affections occur in scorbutic habits. A little camphor is also occasionally added.

=Ointment of Aloes.= See OINTMENT FOR WORMS.

=Ointment of Aloes, Compound.= See OINTMENT FOR WORMS.

=Ointment of Al′um.= _Syn._ UNGUENTUM ALUMINIS, L. _Prep._ 1. Alum, in very fine powder, 1 dr.; lard, 1-1/2 oz. In piles.

2. To the last add of powdered opium, 7 gr. In piles, when there is much pain. See OINTMENT, BANYER’S.

=Ointment, Ammoni′acal.= _Syn._ UNGUENTUM AMMONIACALE, U. AMMONIÆ, L.; LIPAROLE D’AMMONIAQUE, POMMADE DE GONDRET, Fr. _Prep._ 1. (P. Cod.) Suet and lard, of each 1 oz.; melt in a strong wide-mouthed bottle, add of liquor of ammonia (sp. gr. ·923), 2 oz., at once close the bottle, and agitate it until its contents concrete. As little heat as possible should be employed, to prevent unnecessary loss of ammonia.

2. (Gondret.) Lard, 3 parts; suet, 2 parts; almond oil, 1 part; strong solution of ammonia, 6 parts; mix, as before. Rubefacient, vesicant, and counter-irritant. Smeared over the skin and covered so as to prevent evaporation, it raises a blister in 5 or 6 minutes. Its general effects and uses are similar to those of compound liniment of ammonia.

=Ointment of Car′bonate of Ammo′′nia.= _Syn._ UNGUENTUM AMMONIÆ CARBONATIS, U. A. SESQUICARBONATIS, L. _Prep._ From carbonate of ammonia, 1 dr.; lard, 9 dr. An excellent application to painful joints, indolent tumours, scrofulous sores, &c.

=Ointment of Ammo′niated Mercury.= _Syn._ UNGUENTUM HYDRARGYRI AMMONIATI (B. P.). Ammoniated mercury, 62 gr.; simple ointment, 1 oz.; mix. See next preparation.

=Ointment of Ammo′′nio-chloride of Mercury.= _Syn._ WHITE PRECIPITATE OINTMENT; UNGUENTUM HYDRARGYRI AMMONIO-CHLORIDI (Ph. L.), U. H. PRECIPITATI ALBI, U. PRECIP. A. (Ph. E.), U. H SUBMURIATIS AMMONIATI (Ph. D. 1826), L. _Prep._ 1. (Ph. L.) Ammonio-chloride of mercury, 2 dr.; lard, 3 oz.; triturate together.

2. (Ph. E.) As the last, but employing heat.

_Uses, &c._ Alterative; detergent; stimulant. In itch, scald-head, and various other skin diseases; in inflammation of the eyes; as an application to scrofulous and cancerous tumours; to destroy vermin on the body, &c. It “may be safely used” (in small quantities) “on infants.” (A. T. Thomson.)

=Ointment, An′′glo-Saxon.= _Prep._ Heat olive oil, 1 pint, and beeswax, 1/4 lb., until the mixture acquires a reddish-brown colour; then add red lead (levigated), 1/4 lb., and continue the heat, with constant stirring; when the union appears complete, add of amber and burnt alum, of each, in fine powder, 1/2 oz.; lastly, when considerably cooled, add of powdered camphor, 3 dr. As a dressing to foul ulcers.

=Ointment, An′odyne.= See OINTMENT OF OPIUM, HEMLOCK, &c.

=Ointment of An′thracoka′li.= _Syn._ POMADE DE ANTHRACOKALI, Fr. _Prep._ (Dr Polya.) Anthracokali, in very fine powder, 1 part; lard, 30 parts. See ANTHRACOKALI.

=Ointment, Antiherpet′ic.= _Syn._ UNGUENTUM ANTIHERPETICUM, L. _Prep._ 1. (Alibert.) Red sulphide of mercury, 3 dr.; powdered camphor, 1 dr.; lard, 3 oz.

2. (Chevallier.) ‘Subsulphate of mercury’ (Turpeth mineral), 2 dr.; chloride of lime, 3 dr.; almond oil, 6 dr.; lard, 2 oz. In herpes or tetters.

=Ointment, Antimo′nial.= See OINTMENT OF POTASSIO TARTRATE OF ANTIMONY.

=Ointment, Antiperiod′ic.= _Syn._ AGUE OINTMENT; UNGUENTUM ANTIPERIODICUM, U. FEBRIFUGUM, L. _Prep._ 1. Disulphate of quinine, 1-1/2 dr.; saccharine carbonate of iron, 1 dr.; oil of cajeput, 30 drops; fresh butter, 1 oz.

2. (Antonini.) Sulphate of quinine, 1 oz.; rectified spirit and sulphuric acid, of each q. s.; lard, 1 oz.

_Uses, &c._ About 1/4 oz. of either of the above to be rubbed on the vertebral regions once every 2 or 3 hours for 3 or 4 days, in intermittent fevers, more especially in those accompanied by vomiting; or, into the epigastrium, in cholera, diarrhœa, or dysentery.

=Ointment of Araroba.= See ARAROBA.

=Ointment, Aromat′ic.= _Syn._ BALSAMUM STOMACHALE WACKERI, UNGUENTUM AROMATICUM, L. _Prep._ (Ph. Austr. 1836.) Simple ointment, 2-1/2 lbs.; yellow wax and oil of laurel, of each 3 oz.; melt together, and, when considerably cooled, add of oils of juniper, mint, lavender, and rosemary, of each 2 dr. Anodyne, balsamic, and stimulant.

=Ointment, Arsen′ical.= _Syn._ OINTMENT OF WHITE ARSENIC; UNGUENTUM ARSENICALE, U. ARSENICI, U. ACIDI ARSENIOSI, L. _Prep._ 1. Arsenious acid (levigated), 3 gr.; lard or simple ointment, 1 oz. In lepra, psoriasis, malignant whitlows, &c.

2. (Hosp. F.) Levigated white arsenic, 15 to 20 gr.; lard, 1 oz. As a dressing for cancerous sores.

2. (Soubeiran.) White arsenic, 1 dr.; lard, and spermaceti ointment, of each 6 dr. In malignant cancer. The above must be carefully prepared, and used with great caution. See CERATE.

=Ointment of Arse′′niate of I′ron.= _Syn._ UNGUENTUM FERRI ARSENIATIS, L. _Prep._ 1. (Carmichael.) Arseniate of iron, 1/2 dr.; phosphate of iron, 2 dr.; spermaceti ointment, 6 dr.

2. (Dr Pereira.) Arseniate of iron, 1/2 dr.; lard, 1-1/2 oz. In cancer.

=Ointment of Arseniate of Soda.= _Syn._ UNGUENTUM SODÆ ARSENIATIS. _Prep._ Arseniate of soda, 1 dr.; lard, 2 oz. Mix.

=Ointment, Astrin′gent.= _Syn._ UNGUENTUM ASTRINGENS, L. _Prep._ Triturate powdered catechu, 1-1/2 dr., with boiling water, 2 fl. dr., add, gradually, of spermaceti ointment (melted), 1-1/4 oz., and continue the trituration until the mass concretes. An excellent dressing for ill-disposed sores and ulcers, especially during hot weather. See the several LEAD OINTMENTS, OINTMENT OF GALLS, &c.

=Ointment of Atro′′pia.= _Syn._ UNGUENTUM ATROPIÆ (B. P.), L. _Prep._ 1. Atropia, 1-1/2 gr; simple ointment, 1 dr.; mix by careful trituration.

2. (Dr Brookes.) Atropia, 5 gr.; lard, 3 dr.; otto of roses, 1 drop. In neuralgia, rheumatic pains, &c., when the affection is not deeply seated.

3. (B. P.) Atropia, 8 gr.; rectified spirit, 1/2 dr.; lard, 1 oz.; dissolve the atropia in the spirit and mix with the lard.

=Ointment, Bailey’s.= See OINTMENT, ITCH.

=Ointment of Bal′sam of Peru.= _Syn._ UNGUENTUM BALSAMI PERUVIANI, L. _Prep._ 1. Lard or spermaceti ointment, 1 oz.; balsam of Peru, 1 dr.; melt together by the heat of boiling water, stir for 5 or 6 minutes, allow it to settle, and pour off the clear portion. In chaps and abrasions.

2. (Compound; UNG. B. P. COMPOSITUM——Copland.) Lard, 1 oz.; white wax, 1/4 oz.; balsam of Peru, 1 dr,; melt as before, and when nearly cold, add of oil of lavender, 10 or 12 drops. As the last, and to restore the hair.

=Ointment, Banyer’s.= _Syn._ COMPOUND ALUM OINTMENT; UNGUENTUM ALUMINIS COMPOSITUM, U. CALOMELANOS, U. BANYERI, L. _Prep._ From burnt alum and calomel, of each 1-1/2 oz.; carbonate of lead, or litharge (levigated), 2 oz.; Venice turpentine, 1/2 lb.; lard, 2 lbs.; carefully triturated together. In milk-scald, porrigo, &c.

=Ointment of Bark.= See OINTMENT OF CINCHONA.

=Ointment, Basil′icon.= _Syn._ BASILICON, YELLOW B.; UNGUENTUM BASILICUM; U. B. FLAVUM, L. _Prep._ (Ph. L. 1746.) Olive oil, 16 fl. oz.; yellow wax, yellow resin, and Burgundy pitch, of each 1 lb.; melt, remove the vessel from the fire, and stir in of common turpentine, 3 oz. This form is still occasionally employed in some shops, but is generally superseded by the resin cerate and resin ointment of the Pharmacopœias. A nearly similar preparation under the name of ‘basilicon ointment,’ is contained in the Ph. Bor. 1847. (See _below_.)

=Ointment, Basilicon (Black).= See OINTMENT OF PITCH.

=Ointment, Basilicon (Green).= _Syn._ UNGUENTUM BASILICUM VIRIDE, L. _Prep._ (Ph. L. 1746). Prepared verdigris, 1 oz.; yellow basilicon, 8 oz.; olive oil, 3 fl. oz. Detergent. Used to keep down fungous growths, to dress syphilitic ulcers, &c. See CERATE and OINTMENT OF VERDIGRIS.

=Ointment, Bateman’s.= See OINTMENT, ITCH.

=Ointment of Bay-leaves.= See OINTMENT, LAUREL.

=Ointment of Belladon′na.= _Syn._ UNGUENTUM BELLADONNÆ (B. P., Ph. L.). _Prep._ 1. (Ph. L.) Extract of belladonna (deadly nightshade), 1 dr.; lard, 1 oz.; mix by trituration.

2. (Soubeiran.) Fresh belladonna leaves (bruised), 1 part; lard, 2 parts; simmer together until the leaves become crisp, and, after digestion, for a short time longer, drain with pressure.

3. (B. P.) Extract of belladonna, 1; rubbed with a few drops of water and mix with lard, 5-1/2.

_Uses, &c._ As a local anodyne, in painful and indolent tumours, nervous irritations, &c. Also as an application to the neck of the uterus in cases of rigidity. (Chaussier.)

4. Compound; UNGUENTUM BELLADONNÆ COMPOSITUM, L.——_a._ (W. Cooley.) Compound iodine ointment, 7 dr.; extract of belladonna, 1 dr. Powerfully discutient. A most excellent application to all glandular tumours and indurations, buboes, &c., which it is desirable to disperse instead of mature, more especially where there is much pain. It is particularly suitable to cases occurring on shipboard, and when its application (at least twice a day) is accompanied with the internal use of the mixture of iodine and gold (See ANTISCROFULOUS MIXTURE), this treatment has seldom failed, even when the parties were dieted chiefly on salt food.

_b._ (Debreyne.) Extract of belladonna and lard, of each 3 dr.; powdered opium, 1/2 dr. As an external anodyne and benumber, more especially in neuralgia, painful cancerous tumours, &c. A small piece is to be applied to the part, and the friction continued for 6 or 8 minutes. The above preparations are useless unless the extract employed is recent, and of good quality.

=Ointment of Benzoin.= (Ph. U. S.) _Syn._ OINTMENT OF BENZOIN. _Prep._ Tincture of benzoin, 2 oz.; lard, 16 oz.; melt the lard over a water bath and add the tincture, stirring constantly, and when the spirit has evaporated, remove from the water bath, and stir whilst cooling.

=Ointment of Bismuth.= _Syn._ UNGUENTUM BISMUTHI, L. _Prep._ 1. Nitrate of bismuth (‘white bismuth’), 1 dr.; simple ointment, 1 oz.

2. (Fuller.) Nitrate of bismuth, 1 dr.; spermaceti ointment, 19 dr. In itch, and some chronic cutaneous diseases.

=Ointment, Blist′ering.= See OINTMENT OF CANTHARIDES, and VESICANTS.

=Ointment, Blue.= This is the vulgar name in England of mercurial ointment. On the Continent, an ointment made of smalts and Goulard water is commonly so called.

=Ointment of Bo′′rax.= _Syn._ UNGUENTUM BORACIS, L. _Prep._ From borax (in very fine powder), 1 dr.; simple ointment or lard, 7 dr. In excoriations, chaps, &c.

=Ointment of Bromide of Potas′sium.= _Syn._ UNGUENTUM POTASSII BROMIDI, U. POTASSÆ HYDROBROMATIS, L. _Prep._ (Magendie.) Bromide of potassium, 1/2 dr.; lard, 1 oz. Resolvent; in bronchocele, scrofula, &c.

=Ointment of Bro′mine.= _Syn._ UNGUENTUM BROMINII, U. B. COMPOSITUM, L. _Prep._ (Magendie.) Bromide of potassium, 20 gr.; bromine, 6 to 12 drops; lard, 1 oz. As the last, but more active.

=Ointment, Brown.= _Syn._ FRENCH POOR-MAN’S FRIEND; UNGUENTUM FUSCUM, U. HYDRARGYRI, F., L. _Prep._ (P. Cod.) Nitric oxide of mercury (levigated), 1/2 dr.; resin ointment, 1 oz. In ophthalmia (cautiously), after the inflammatory stage is over; as an application to sore legs, &c.

=Ointment of Cad′mium.= _Syn._ UNGUENTUM CADMII, U. C. SULPHATIS, L. _Prep._ (Radius.) Sulphate of cadmium, 1 to 2 gr.; pure lard, 1 dr.; carefully triturated together. In specks on the cornea.

=Ointment of Cadmium, Iodide of.= (B. Ph.) _Syn._ UNGUENTUM CADMII IODIDI. _Prep._ Mix thoroughly iodide of cadmium in fine powder, 62 gr., with simple ointment, 1 oz.

=Ointment of Caffeine.= _Syn._ UNGUENTUM CAFFEINÆ. _Prep._ Citrate of caffeine, 8 gr.; lard, 10 oz. Mix.

=Ointment of Cala′mine.= _Syn._ UNGUENTUM CALAMINÆ, U. LAPIS CALAMINARIS, U. ZINCI CARBONATIS IMPURI, L. _Prep._ (Ph. D. 1826.) Prepared calamine, 1 lb.; ointment of yellow wax, 5 lbs. Desiccative and healing. This is the old Dublin form for Turner’s cerate.

=Ointment of Cal′omel.= _Syn._ UNGUENTUM HYDRARGYRI SUBCHLORIDI (B. P.), UNGUENTUM CALOMELANOS, U. HYDRARGYRI CHLORIDI, L. _Prep._ 1. From calomel, 1 dr.; lard, or simple ointment, 1 oz.

_Obs._ “Were I required to name a local agent pre-eminently useful in skin diseases generally, I should fix on this. It is well deserving a place in the Pharmacopœia.” (Pereira.) Dr Underwood uses elder-flower ointment as the vehicle.

2. (Compound; UNGUENTUM CALOMELANOS COMPOSITUM——Dr A. T. Thomson.) Calomel, 1 dr.; tar ointment, 4 dr.; spermaceti ointment, 1 oz.

3. (B. P.) Calomel, 1; prepared lard, 5-1/2; mix. In lepra.

=Ointment of Cam′phor.= _Syn._ UNGUENTUM CAMPHORÆ, L. _Prep._ 1. Camphor, 1 to 2 dr.; lard, 1 oz.; dissolve by a gentle heat and stir until the mass is nearly cold. Stimulant and anodyne; in prurigo, psoriasis, &c.

2. (Compound.) From powdered opium, 1/2 dr.; powdered camphor, 1-1/2 dr.; lard, 1-1/4 oz.; mix by trituration. As an anodyne friction in rheumatic pains, swelled joints, colic, &c.

=Ointment of Canthar′ides.= _Syn._ UNGUENTUM CANTHARIDIS (B. P., Ph. L., D., & U. S.), U. LYTTÆ, L. _Prep._ 1. (Ph. L.) Cantharides (in very fine powder), 3 oz.; distilled water, 12 fl. oz.; mix, boil to one half, to the strained liquid add of resin cerate, 1 lb., and evaporate to a proper consistence.

2. (Ph. D.) Liniment of Spanish flies, 8 fl. oz.; white wax, 3 oz.; spermaceti, 1 oz.; melt together with a gentle heat, and stir until it concretes.

3. (Ph. E.)——_a._ UNGUENTUM INFUSUI CANTHARIDIS——Ph. E. Powdered Cantharides 1 oz.; boiling water, 1/4 pint; infuse one night (12 hours), strain with expression, add of lard 2 oz., and boil until the water is expelled; then add beeswax and resin, of each 1 oz., and when these are liquefied, remove the vessel from the fire, and further add of Venice turpentine, 2 oz.

_b._ (UNGUENTUM PULVERIS CANTHARIDIS——Ph. E.) Resin ointment, 7 oz.; melt, add of cantharides (in fine powder), 1 oz., and stir until the whole is nearly cold.

4. (B. P.) Cantharides, in fine powder, 1; olive oil, 6; yellow wax, 1; digest the cantharides in the oil for 12 hours, and for 1/4 hour at 212°; strain, add the melted wax, and stir till cold.

_Obs._ The above preparations are frequently called ‘blister ointment’ or ‘epispastic ointment.’ They are used to keep blisters open after they have been produced by stronger compounds. The first three compounds are regarded as milder than the last (3, _b_), which contains the flies in substance. The P. Cod. contains an ointment (UNG. EPISPASTICUM FLAVUM) which is weaker than the above, prepared by digesting the bruised flies in lard, for 3 hours, over a warm bath; about 1/6th part of wax is next added to the strained fat, which is then coloured with turmeric, and scented with oil of lemon. See CERATE, POMMADE, VESICANTS, and _below_.

=Ointment of Cantharides, Extract of.= (M. Cap.) _Syn._ UNGUENTUM CUM EXTRACTO CANTHARIDIS. _Prep._ Alcoholic extract of cantharides, 8 gr.; oil of roses, 1 dr.; beef marrow, 2 oz.; oil of lemon, 40 minims. To promote the growth of the hair.

=Ointment of Cantharides with Mercury.= _Syn._ UNGUENTUM CANTHARIDIS CUM HYDRARGYRO. _Prep._ Lard, 65 parts; Spanish flies, 29 parts; strong mercurial ointment, 6 parts. Mix. Used in Normandy to indolent tumours.

=Ointment of Canthar′idine.= _Syn._ UNGUENTUM CANTHARIDINÆ, L. _Prep._ (Soubeiran.) Cantharidine, 1 gr.; white wax, 1 dr.; lard, 7 dr.; mix thoroughly. (See _above_.)

=Ointment of Cap′sicum.= _Syn._ UNGUENTUM CAPSICI, L. _Prep._ (Dr Turnbull.) Tincture of capsicum (pure), q. s.; gently evaporate it until it begins to gelatinise, then mix the extract with twice its weight of lard. As a powerful stimulant and rubefacient. When very freely used, it vesicates.

=Ointment of Car′bonate of Am′′monia.= See OINTMENT, AMMONIACAL.

=Ointment of Carbolic Acid.= (Ph. U. S.) _Syn._ UNGUENTUM ACIDI CARBOLICI. _Prep._ Carbolic acid, 60 gr.; simple ointment, 480 gr.

=Ointment of Car′bonate of Lead.= _Syn._ WHITE LEAD OINTMENT; UNGUENTUM PLUMBI CARBONATIS (P. B., Ph. E. & D.), U. CERUSSÆ, L. _Prep._ 1. (Ph. E.) Carbonate of lead, 1 oz.; simple ointment, 5 oz.; mix thoroughly.

2. (Ph. D.) Carbonate of lead, 3 oz.; ointment of white wax, 1 lb.; mix with heat.

3. (B. P.) Carbonate of lead, in fine powder, 1; simple ointment, 7. Mix.

4. UNGUENTUM PLUMBI CAMPHORATUM——(E., 1744). Add to the last 2 scruples of camphor ground with a little oil.

_Uses, &c._ Cooling; desiccative. Useful to promote the healing of excoriated parts and slight ulcerations. The camphorated white ointment of old pharmacy (UNG. ALBUM CAMPHORATUM——Ph. L. 1744) was made by adding 40 gr. of camphor to the first of the above.

=Ointment of Cat′echu.= _Syn._ UNGUENTUM CATECHU, L. _Prep._ From alum, 1 oz.; catechu, 3 oz.; (both in very fine powder;) added to olive oil, 1/2 pint, and yellow resin, 4 oz., previously melted together. Used to dress ulcers in hot climates, where the ordinary fat ointments are objectionable; also in this country during hot weather. See OINTMENT, ASTRINGENT.

=Ointment of Chalk.= _Syn._ UNGUENTUM CRETÆ. _Prep._ Prepared chalk, 1 oz.; lard, 4 oz. Mix.

=Ointment of Chamomile.= (M. Bazin.) _Syn._ UNGUENTUM ANTHEMIDIS. _Prep._ Freshly powdered chamomile flowers, olive oil, and lard, in equal quantities. For the cure of itch.

=Ointment of Char′coal.= _Syn._ UNGUENTUM CARBONIS, L. _Prep._ 1. Resin ointment, 10 dr.; recently burnt charcoal (levigated), 3 dr. As a dressing to foul ulcers, especially those of the legs.

2. (Caspar.) Lime tree charcoal and dried carbonate of soda, of each 2 dr,; rose ointment, 1 oz., or q. s. In scald-head.

3. (Radius.) Animal charcoal (recent), 1 part; mallow ointment, 2 parts. As a friction in glandular enlargements and indurations, as a dressing to fetid ulcers, &c.

=Ointment of Cher′ry-Laurel.= _Syn._ UNGUENTUM LAURO-CERASI, L. _Prep._ (Soubeiran.) Essential oil of cherry-laurel, 1 dr.; lard, 1 oz. To alleviate the pain in cancer, neuralgia, and other local affections.

=Ointment, Chil′blain.= _Syn._ UNGUENTUM AD PERNIONES, L. _Prep._ 1. From made mustard (very thick), 2 parts; almond oil and glycerine, of each 1 part; triturated together. To be applied night and morning.

2. (Cottereau.) Acetate of lead, camphor, and cherry-laurel water, of each 1 dr.; tar, 1-1/2 dr.; lard, 1 oz.

3. (Devergie.) Creasote and Goulard’s extract, of each 12 drops; extract of opium, 1-1/2 gr.; lard, 1 oz. Twice or thrice daily.

4. (Giacomini.) Sugar of lead, 2 dr.; cherry-laurel water (distilled), 2 fl. dr.; lard, 1 oz.

5. (Linnæus.) Balsam of Peru, 1 dr.; hydrochloric acid, 2 dr.; spermaceti ointment, 2-1/2 oz.

_Obs._ For Swediaur’s, Vance’s, and Wahler’s ointments, see article CHILBLAIN.

=Ointment of Chloral Hydrate.= (Dowault.) _Syn._ UNGUENTUM CHLORALIS HYDRAS. _Prep._ Chloral hydrate, 2 parts; lard, 20 parts. Stimulant; stronger if required as a rubefacient.

=Ointment of Chlo′′ride of Cal′cium.= _Syn._ UNGUENTUM CALCII CHLORIDI, U. CALCIS MURIATIS†, L. _Prep._ (Sundelin.) Chloride of calcium (dry), 1 dr.; strong vinegar, 40 gr.; foxglove (recent, in fine powder), 2 dr.; lard, 1 oz. In bronchocele, scrofulous tumours, &c.

=Ointment of Chloride of Lead.= _Syn._ UNGUENTUM PLUMBI CHLORIDI, L. _Prep._ (Tuson). Chloride of lead, 1 part; simple cerate, 8 parts; carefully triturated together. In painful cancerous ulcerations and neuralgic tumours. See LEAD (Chloride).

=Ointment of Chloride of Lime.= See OINTMENT OF HYPOCHLORITE OF LIME.

=Ointment of Chloride of Mercury.= See OINTMENTS OF CALOMEL and CORROSIVE SUBLIMATE.

=Ointment of Chlo′′rine.= _Syn._ UNGUENTUM CHLORINII, L. _Prep._ (Augustin.) Chlorine water, 1 part; lard, 8 parts; well triturated together. In itch, lepra, ringworm, fetid ulcers, &c.

=Ointment of Chlor-i′odide of Mercury.= _Syn._ UNGUENTUM HYDRARGYRI CHLORIODIDI, L. _Prep._ (M. Recamier.) Chloriodide (iodo-chloride) of mercury, 3 gr.; lard, 5 dr. Recommended as a powerful discutient or resolvent. See OINTMENT OF IODO-CHLORIDE OF MERCURY.

=Ointment of Chlo′′roform.= _Syn._ UNGUENTUM CHLOROFORMI, L. _Prep._ (M. Louis.) Chloroform, 1 dr.; simple ointment, 1 oz. In neuralgia and rheumatic pains, &c. It must be kept in a stoppered, wide-mouthed phial.

=Ointment of Cin′chona.= _Syn._ OINTMENT OF BARK; UNGUENTUM CINCHONÆ, L. _Prep._ (Biett.) Red cinchona bark (in very fine powder) and almond oil, of each 1 part; beef marrow (prepared), 3 parts. In the variety of scald-head termed porrigo decalvans. A little oil of mace or tar is a useful addition.

=Ointment, Cit′rine.= See OINTMENT OF NITRATE OF MERCURY.

=Ointment of Cobalt, Oxide of.= (Amst. Ph.) _Syn._ UNGUENTUM OXIDI COBALTI. _Prep._ Simple cerate, 16 oz.; liquid subacetate of lead, 4 oz.; powdered smalt, 4 oz.

=Ointment of Coc′culus In′dicus.= _Syn._ UNGUENTUM COCCULI (Ph. E.), L. _Prep._ (Ph. E.) Kernels of _Cocculus indicus_, 1 part; beat them to a smooth paste in a mortar, first alone, and next with a little lard; then further add of lard, q. s., so that it may be equal to 5 times the weight of the kernels. Used to destroy pediculi, and in scald-head, &c.

=Ointment of Cod-liver Oil.= _Syn._ UNGUENTUM OLEI MORRHUÆ, U. O. JECORIS ASELLI, L. _Prep._ Cod-liver oil (pale and recent), 7 parts; white wax and spermaceti, of each 1 part; melted together. In ophthalmia and opacity of the cornea, either alone or combined with a little citrine ointment; as a friction or dressing for scrofulous indurations and sores; in rheumatism, stiff joints, and in several skin diseases. It often succeeds in porrigo or scald-head when all other remedies have failed. Scented with oil of nutmeg and balsam of Peru, it forms an excellent pomade for strengthening and restoring the hair.

=Ointment of Col′ocynth.= _Syn._ UNGUENTUM COLOCYNTHIDIS, L. _Prep._ (Chrestien.) Colocynth pulp (in very fine powder), 1 part; lard, 8 parts. Used in frictions on the abdomen as a hydragogue purgative, in mania, dropsy, &c.

=Ointment of Corrosive Sub′limate.= _Syn._ OINTMENT OF CHLORIDE OF MERCURY; UNGUENTUM HYDRARGYRI CHLORIDI, L. _Prep._ 1. From corrosive sublimate, 2 to 5 gr.; rub it to powder in a glass or wedgwood-ware mortar; add of rectified spirit, 6 or 7 drops, or q. s.; again triturate; lastly add, gradually, of spermaceti ointment (reduced to a cream-like state by heat), 1 oz., and continue the trituration until the whole concretes. Used as a stimulant, detergent, and discutient application in various local affections; in lepra, porrigo, acne, &c., and as a dressing to syphilitic and some other ulcers.

2. (Ph. Chirur.) Corrosive sublimate, 10 gr.; yolk of 1 egg; lard, 1 oz. As a dressing.

3. (POMMADE DE CIRILLO——P. Cod.) Corrosive sublimate, 1 dr.; lard, 1 oz. Caustic; must not be confounded with the preceding.

=Ointment, Cosmet′ic.= _Syn._ UNGUENTUM COSMETICUM, L.; POMMADE DE LA JEUNESSE, Fr. _Prep._ (Quincey.) Spermaceti, 3 dr. (better, 4-1/2 dr.); oil of almonds, 2 oz.; melt together, and, when cooled a little, stir in of nitrate of bismuth (‘white bismuth’), 1 dr.; and, lastly, of oil of rhodium, 6 drops. In itch and some other cutaneous eruptions; but chiefly as a pomade for the hair. Its frequent use is said to turn the latter black.

=Ointment of Cre′asote.= _Syn._ UNGUENTUM CREASOTI (B. P., Ph. L. E. D. & U. S.), L. _Prep._ 1. (Ph. L.) Creasote, 1/2 fl. dr.; lard, 1 oz.; triturate together.

2. (Ph. E.) Lard, 3 oz.; melt it by a gentle heat; add of creasote, 1 dr., and stir the mixture until it is nearly cold.

3. (Ph. D.) Creasote, 1 fl. dr.; ointment of white wax, 7 dr.; as the last.

4. (B. P.) Creasote, 1; simple ointment, 8. Mix.

_Uses, &c._ In several skin diseases, especially ringworm; as a friction in tic-douloureux; a dressing for scalds and burns; an application to chilblains, &c.

=Ointment of Cro′ton Oil.= _Syn._ UNGUENTUM CROTONIS, L. _Prep._ 1. Croton oil, 15 to 30 drops; lard (softened by heat), 1 oz.; mix well. This is the usual and most useful strength to prepare the ointment. Rubefacient and counter-irritant; in rheumatism and various other diseases. When rubbed repeatedly on the skin, it produces redness and a pustular eruption. It also often affects the bowels by absorption. The only advantage it possesses over other preparations of the class is the rapidity of its action.

2. (RUBEFACIENT POMADE——Caventou.) White wax, 1 part; lard, 5 parts; melt together, and, when quite cold, mince it small, add of croton oil, 2 parts, and mix by trituration. Stronger than the last.

=Ointment of Cy′anide of Mer′cury.= _Syn._ UNGUENTUM HYDRARGYRI CYANIDI, L. _Prep._ 1. (Cazenave.) Cyanide of mercury, 8 gr.; lard, 1 oz.; carefully triturated together.

2. (Pereira.) Cyanide of mercury, 10 to 12 gr.; lard, 1 oz. As a dressing for scrofulous and syphilitic ulcers, &c.; as an application in psoriasis, moist tetters, and some other skin diseases, &c. Biett orders the addition of a few drops of essence of lemon.

=Ointment of Cyanide of Potas′sium.= _Syn._ UNGUENTUM POTASSII CYANIDI, L. _Prep._ (Cazenave.) Cyanide of potassium, 12 gr.; oil of almonds, 2 dr.; triturate, add of cold cream (dry), 2 oz., and mix by careful trituration. As an anodyne in neuralgia, rheumatism, swelled joints, &c.; also as a friction over the spine in hysteria, and over the epigastrium in gastrodynia, &c.

=Ointment of Delphin′ine.= _Syn._ UNGUENTUM DELPHINIÆ, L. _Prep._ (Dr Turnbull.) Delphinine or delphinia, 10 to 30 gr.; olive oil, 1 dr.; lard, 1 oz.; mix as the last. Used as a friction in rheumatism, and the other cases in which veratrine is employed.

=Ointment, Depil′atory.= _Syn._ UNGUENTUM DEPILATORIUM, L. See DEPILATORY (Cazenave’s).

=Ointment, Desic′cative.= _Syn._ DRYING OINTMENT; UNGUENTUM DESICCATIVUM, U. EXSICCANS, L. See the OINTMENTS OF CALAMINE, LEAD, ZINC, &c.

=Ointment, Deter′gent.= _Syn._ UNGUENTUM DETERGENS, L. The OINTMENTS OF NITRATE OF MERCURY, NITRIC OXIDE OF MERCURY, TAR, VERDIGRIS, &c., when not too strong, come under this head.

=Ointment, Diges′tive.= _Syn._ UNGUENTUM DIGESTIVUM, L. _Prep._ 1. (P. Cod.) Venice turpentine, 2 oz.; yolks of 2 eggs; mix, and add of oil of St John’s wort, 1/2 oz.

2. (DIGESTIF ANIMÉ——P. Cod.) As the last, with an equal weight of liquid styrax.

3. (DIGESTIF MERCURIEL——P. Cod.) As No. 1, with an equal weight of mercurial ointment.

4. (UNG. D. VIRIDE——Dr Kirkland.) Beeswax, gum elemi, and yellow resin, of each 1 oz.; green oil, 6 oz.; melt them together, and, when considerably cooled, add of oil of turpentine 2 dr.

=Ointment, Edinburgh.= Two compounds are known under this name:——1. (BROWN.) From black basilicon, 6 parts; milk of sulphur, 2 parts; sal ammoniac, 1 part.

2. (WHITE.) From white hellebore, 3 oz.; sal ammoniac, 2 oz.; lard, 1 lb. Both are used in itch.

=Ointment of Eggs.= _Syn._ UNGUENTUM OVORUM, L. _Prep._ 1. Yolk of 1 egg; honey and fresh linseed oil, of each 1 oz.; balsam of Peru, 1/2 dr.; mix well.

2. (Soubeiran.) Beeswax, 4 dr.; oil of almonds, 1-1/2 oz.; yolk of 1 egg. As an emollient and soothing dressing to excoriations, irritable ulcers, &c.

=Ointment, Egyp′tian.= _Prep._ (Giordano.) Burnt alum, 1 part; verdigris, 10 parts; strong vinegar, 14 parts; purified honey (thick), 32 parts; mix by heat and agitation. As a detergent application to foul ulcers. It is a modification of the ‘UNGUENTUM ÆGYPTIACUM’ of old pharmacy.

=Ointment of Elder-flowers.= _Syn._ WHITE ELDER-OINTMENT; UNGUENTUM SAMBUCI FLORUM, U. SAMBUCI (Ph. L.), L. _Prep._ 1. (Ph. L.) Elder flowers and lard, of each 1 lb.; boil them together until the flowers become crisp, then strain, with pressure, through a linen cloth. The same precautions must be observed as are necessary in the preparation of the medicated oils, by infusion. Emollient; less white and odorous than the following:——

2. (Wholesale.) Take of lard (hard, white, and sweet), 25 lbs.; prepared mutton suet, 5 lbs.; melt them in a well-tinned copper or earthen vessel, add of elder-flower water 3 galls., agitate briskly for about 1/2 an hour, and set it aside; the next day gently pour off the water, remelt the ointment, and add of benzoic acid, 5 dr.; otto of roses, 20 drops; oil of bergamot and oil of rosemary, of each 1 dr.; again agitate well, let it settle for 10 minutes, and then pour off the clear portion into pots for sale. Very agreeable, and keeps well.

_Obs._ The last formula is the one now generally adopted by the large wholesale houses.

=Ointment of Elder-leaf.= _Syn._ ELDER OINTMENT, GREEN E. O.; UNGUENTUM VIRIDE, U. SAMBUCI VIRIDE, U. SAMBUCI (Ph. D. 1826), L. _Prep._ 1. (Ph. D. 1826.) Fresh elder leaves (bruised), 3 lbs.; suet, 4 lbs.; lard, 2 lbs.; boil together, as above.

2. (Wholesale.) Good fresh lard, 1 cwt.; fresh elder leaves, 56 lbs.; boil till crisp, strain off the oil, put it over a slow fire, add hard prepared mutton suet, 14 lbs., and gently stir it until it acquires a bright green colour.

_Obs._ The above ointment is reputed to be emollient and cooling, and has always been a great favourite with the common people. Both elder-flower and elder-leaf ointment are, however, unnecessary preparations. “They are vestiges of the redundant practice of former times.” (A. T. Thomson.) The above formulæ are those now almost exclusively employed in trade. The ointment should be allowed to cool very slowly, and after its temperature has fallen a little, and it begins to thicken, it should not be stirred, in order that it may ‘grain’ well, as a granular appearance is much admired. It is a common practice to add powdered verdigris to deepen the colour, but then the ointment does not keep well. This dangerous fraud may be detected in the manner noticed under CERATE, SAVINE.

=Ointment of Elecampane.= _Syn._ UNGUENTUM INULÆ. _Prep._ Fresh elecampane root (boiled till soft and pulped), 1-1/2 oz.; lard, 1 oz. Mix.

=Ointment of El′emi.= _Syn._ BALSAM OF ARCÆUS†, UNGUENTUM ELEMI (B. P., Ph. L. & D.), L. _Prep._ 1. (Ph. L.) Elemi, 3 oz.; suet, 6 oz.; melt them together, remove the vessel from the fire, and stir in of common turpentine, 2-1/2 oz.; olive oil, 1/2 fl. oz.; lastly, strain the whole through a linen cloth.

2. (Ph. D.) Resin of elemi, 4 oz.; ointment of white wax, 1 lb; melt them together, strain through flannel, and stir the mixture constantly until it concretes.

3. (B. P.) Elemi, 1; simple ointment, 4; melt and strain.

_Uses, &c._ Stimulant and digestive. It is frequently employed to keep open issues and setons, and as a dressing for old and ill-conditioned sores. The ‘UNG. ELEMI CUM ÆRURINE’ of St George’s Hospital is made by adding 1 dr. of finely powdered verdigris to every 6 oz. of the ointment.

=Ointment of Emetina.= (Dr Turnbull.) _Syn._ UNGUENTUM EMETINÆ. _Prep._ Emetine, 15 gr.; rectified spirit, q. s.; lard, 1/2 oz. Used as a rubefacient.

=Ointment Escharot′ic.= _Syn._ UNGUENTUM ESCHAROTICUM, L. _Prep._ 1. (Sir B. Brodie.) Corrosive sublimate, 1 dr.; nitric oxide of mercury, sulphate of copper, and verdigris, of each 2 dr. (all in very fine powder); lard, q. s. See OINTMENT, and CERATE, ARSENICAL.

=Ointment of Euphorbium.= (Dr Neligan.) _Syn._ UNGUENTUM EUPHORBII. _Prep._ Powdered euphorbium, 25 to 30 gr.; lard, 1 oz.; mix. To keep up a discharge from issues.

=Ointment of Glycerin.= _Syn._ UNGUENTUM GLYCERINI. _Prep._ Glycerin, 4 fl. oz.; oil of almonds, 8 fl. oz.; wax and spermaceti, of each 1/2 oz.

=Ointment, Eye.= _Syn._ EYE SALVE; UNGUENTUM OPHTHALMICUM, L. _Prep._ 1. (Dr Collier.) Burnt alum, 1/2 dr.; powdered opium, 20 gr.; olive oil, 1 fl. dr.; spermaceti ointment, 2 dr. In inflammation of the eyelids, purulent ophthalmia, &c.

2. (W. Cooley.) Chloride of barium, 6 gr.; calomel, 10 gr.; simple ointment, 1 oz.; otto of roses, 1 or 2 drops. In scrofulous ophthalmia.

3. (Dessault.) Nitric oxide of mercury, carbonate of zinc, acetate of lead, and dried alum, of each 1 dr.; corrosive sublimate, 10 gr.; rose ointment, 1 oz. In chronic ophthalmia, profuse discharges, &c.; in general, diluted.

4. (Dupuytren.) Red oxide of mercury, 10 gr.; sulphate of zinc, 20 gr.; lard, 2 oz. For chronic inflammation of the eyelids, chronic ulcers, &c.

5. (Fricke). Nitrate of silver, 10 gr.; zinc ointment, 2 dr.; balsam of Peru, 1/2 dr. In ulceration of the cornea, and in acute, purulent, and chronic ophthalmia, &c., employing great caution in its use.

6. (Guthrie.) Spermaceti ointment, 1 dr.; solution of diacetate of lead, 15 drops; nitrate of silver, 2 to 10 gr. As the last, and in cases wherein a direct caustic action is desired. The stronger ointment often occasions intense pain.

7. (Hufeland.) Black oxide of mercury, 2 gr.; spermaceti cerate and walnut oil, of each 1 dr. In chronic affections of the eyes or eyelids, particularly in those of a syphilitic character.

8. (Janin.) Ammonio-chloride of mercury, 1 dr.; tutty and bole, of each 2 dr.; lard, 1 oz. In debility of the conjunctiva, in chronic inflammation with excessive secretion, &c.

9. (Marshall.) See CERATE (Marshall’s).

10. (Parker.) Iodine, 1 gr.; iodide of potassium, 5 gr.; simple ointment, 3 dr. In scrofulous ophthalmia, thickening of the conjunctiva, opacity of the cornea, &c.

11. (Pellier.) Nitric oxide of mercury and carbonate of zinc, of each 1-1/2 dr.; tutty, 1/2 dr.; red sulphuret of mercury, 20 gr.; lard, 2 oz; balsam of Peru, 15 drops. In specks in the eye arising from small ulcers which have healed up; in excessive defluxions, &c.

12. (Ratier.) Liquor of diacetate of lead, 1/2 dr.; wine of opium, 1 dr.; lard, ·5 dr. In excoriations, and the variety of chronic ophthalmia popularly termed ‘blear eye.’

13. (Regent). Acetate of lead and red precipitate, of each 1 dr.; camphor, 6 gr.; washed fresh butter, 2-1/2 oz. As the last, and in chronic ulcerations.

14. (Singleton’s GOLDEN OINTMENT.) According to Dr Paris, this compound consists of lard medicated with orpiment (native yellow sulphuret of arsenic). There appears, however, to be some mistake in this, as that sold us under the name had nearly the same composition as the OINTMENT OF NITRIC OXIDE OF MERCURY of the Pharmacopœia. It did not contain even a trace of either arsenic or sulphur. The action of this nostrum, and the reputation which it has acquired, fully justify this conclusion.

15. (Smellome.) From verdigris (levigated), 1/2 dr.; olive oil, 1 fl. dr.; triturate together; add of yellow basilicon, 1 oz, and again triturate until it begins to concrete. A popular nostrum, sometimes useful in chronic inflammation and ulcerations of the eyelids, &c., especially in those of a scrofulous character.

16. (Spielmann.) Acetate of lead, 20 gr.; spermaceti cerate, 5 dr.; compound tincture of benzoin, 40 gr. Cooling; desiccative. In inflamed eyelids, excoriations, &c.

17. (St Yve.) Fresh butter (washed), 1 oz.; white wax, 1 dr.; camphor, 15 gr.; melt by a gentle heat, and, when cooled a little, add of red precipitate (levigated), 1/2 dr.; oxide of zinc, 20 gr. In chronic inflammation of the coats of the eye, or of the eyelids, specks on the cornea, &c.

18. (Thomson.) Levigated oxide of zinc, 1 dr.; lard, 9 dr.; wine of opium, 20 drops. In chronic ophthalmia depending on want of tone in the vessels and integuments of the eye.

19. (Velpeau.) Precipitated sesquioxide of iron (recent, but dry), 1/2 dr.; lard, 5 dr.; oil of almonds, 1 fl. dr.; balsam of Peru, 15 drops. As the last, especially in ‘blear eye.’

20. (Ware.) Wine of opium, 1 fl. dr.; simple ointment, 3 dr. In ophthalmia, after the inflammatory symptoms have subsided, and the vessels remain red and turgid.

_Obs._ The ingredients entering into the composition of all the above ointments must be reduced to the state of impalpable powder before mixing them; and the incorporation should be made by long trituration in a wedgwood-ware mortar, or, preferably, for those that contain substances that are very gritty, by levigation on a porphyry slab, with a muller. The most serious consequences, even blindness, have resulted from the neglect of these precautions. They should all be employed in exceedingly small quantities at a time, and they should be very carefully applied by means of a camel-hair pencil or a feather; and, in general, not until acute inflammation has subsided. The stronger ones, in most cases, require dilution with an equal weight to twice their weight of lard or simple ointment, and should only be used of their full strength under proper medical advice. Various other formulæ for OPHTHALMIC OINTMENTS will be found under the names of their leading ingredients.

=Ointment of Fig′wort.= See OINTMENT OF SCROPHULARIA.

=Ointment of Fox′glove.= _Syn._ UNGUENTUM DIGITALIS, L. _Prep._ 1. From fresh foxglove as ointment of hemlock——Ph. L. As an application to chronic ulcers, glandular swellings, &c.

2. (Rademacher.) Extract of foxglove, 2 dr.; lard, 1 oz. In croup; spread on lint, and applied as a plaster to the throat.

=Ointment of Fu′ligokali.= See FULIGOKALI.

=Ointment of Galls.= _Syn._ UNGUENTUM GALLÆ (B. P., Ph. D.), L. _Prep._ 1. (Ph. D.). Gall-nuts (in very fine powder), 1 dr.; ointment of white wax, 7 dr.; rub them together until a uniform mixture is obtained.

2. (B. P.) Galls, in very fine powder, 80 gr.; benzoated lard, 1 oz. Mix. An excellent application to piles, either alone or mixed with an equal quantity of zinc ointment; also highly useful in ringworm of the scalp.

=Ointment of Galls and Opium.= UNGUENTUM GALLÆ CUM OPIO (B. P.); UNGUENTUM GALLÆ OPIATUM, U. GALLÆ COMPOSITUM——Ph. L., U. GALLÆ ET OPII——(Ph. E.)——_Prep._ 1. (Ph. L.) Gall-nuts (very finely powdered), 6 dr.; powdered opium, 1-1/4 dr.; lard, 6 oz.; rub them together.

2. (Ph. E.) Galls, 2 dr.; opium, 1 dr.; lard, 1 oz.; as the last.

3. (B. P.) Ointment of galls, 1 oz.; opium (in powder), 32 gr. Mix.

_Uses, &c._ A most valuable astringent and anodyne in blind piles, slight cases of prolapsus ani, &c. Some practitioners add 1 dr. of camphor. The ointment of the Ph. E. is much the strongest.

OINTMENT OF GALLS WITH MORPHIA. UNGUENTUM GALLÆ ET MORPHIÆ——(Dr Paris.) Morphia, 2 gr.; olive oil (hot), 2 fl. dr.; triturate, add of zinc ointment (Ph. L.), 1 oz.; powdered galls, 1 dr.; and mix thoroughly. In piles. The quantity of galls should be doubled.

=Ointment of Galls with Camphor.= _Syn._ UNGUENTUM GALLÆ CUM CAMPHORÂ. _Prep._ Galls, 2 dr.; camphor, 1/2 dr.; lard, 1 oz. Mix them.

=Ointment of Garlic.= _Syn._ UNGUENTUM ALLII, L. _Prep._ 1. Fresh garlic (bruised), 2 parts; lard, 3 parts; simmer together for 1/2 an hour, and then strain with expression. Rubbed on the abdomen in chronic diarrhœa and colic, and over the chest and spine in hooping-cough.

2. (Beasley.) Fresh garlic and lard, equal parts; beaten together. Applied to the feet in hooping-cough.

=Ointment, Giacomini’s.= See OINTMENT, CHILBLAIN.

=Ointment of Gold.= _Syn._ UNGUENTUM AURI, L.; POMMADE D’OR, Fr. _Prep._ 1. (Legrand.) Gold (in powder), 12 gr.; lard, 1 oz. As a dressing for syphilitic ulcers; and as a friction in glandular indurations, &c.; also endermically.

2. (Magendie.) Amalgam of gold, 1 dr.; lard, 1 oz. For endermic use, chiefly. When the surface becomes dry, the ointment of terchloride of gold is to be substituted as a dressing. In rheumatic pains, neuralgia, &c.

=Ointment, Gold′en.= See OINTMENT, EYE, CITRINE O., &c.

=Ointment, Gondret’s.= See OINTMENT, AMMONIACAL.

=Ointment, Goulard’s.= _Syn._ UNGUENTUM GOULARDI, U. LITHARGYRI ACETATIS, L. _Prep._ (Ph. Chirur.) Goulard’s extract, 1 dr.; simple ointment, 2 oz. See CERATE (Lead).

=Ointment, Green.= See OINTMENT, ELDER.

=Ointment of Guarana.= _Syn._ UNGUENTUM GUARANÆ. _Prep._ One part of extract of guarana to eight parts of lard.

=Ointment of Hel′lebore.= _Syn._ OINTMENT OF WHITE HELLEBORE; UNGUENTUM VERATRI, L. _Prep._ 1. (Ph. L. 1836.) White hellebore (in very fine powder), 2 oz.; lard, 8 oz.; oil of lemons, 20 drops. In itch, lepra, ringworm, &c.; and to destroy insects in the hair of children. It should be used with caution, and, preferably, diluted with an equal weight of lard.

2. (Compound; UNGUENTUM VERATRI COMPOSITUM.)——_a._ (Rayer.) White hellebore, 1 oz.; sal ammoniac, 1/2 oz.; lard, 8 oz. Used as the last.

_b._ See SULFUR OINTMENT (Compound)——Ph. L.

=Ointment of Hem′lock.= _Syn._ UNGUENTUM CONII (Ph. L.), L. _Prep._ 1. (Ph. L.) Fresh hemlock leaves and lard, of each 1 lb.; boil them together (very gently) until the leaves become crisp, then strain through linen, with pressure. See OILS (Medicated).

2. Extract of hemlock, 1 dr.; lard, 9 dr.; triturate together.

_Uses, &c._ As a local anodyne in neuralgic and rheumatic pains, glandular enlargements, painful piles, &c.; and as a dressing to painful and irritable ulcers, cancerous sores, &c.

=Ointment of Hen′bane.= _Syn._ UNGUENTUM HYOSCYAMI, L. _Prep._ 1. Fresh henbane leaves, 1 lb.; lard, 2 lbs.; boil until nearly crisp.

2. (Taddei.) Extract of henbane, 1 dr.; lard, 1 oz. Anodyne; in painful piles, sores, &c., as the last.

=Ointment, Holloway’s.= See PATENT MEDICINES.

=Ointment of Hops.= _Syn._ UNGUENTUM LUPULI, L. _Prep._ (Swediaur.) Hops (commercial), 2 oz.; lard, 10 oz.; as extract of hemlock, Ph. L. In painful piles and cancerous sores.

=Ointment of Hydri′odate of Ammo′′nia.= _Syn._ UNGUENTUM AMMONIÆ HYDRIODATIS, L. _Prep._ From hydriodate of ammonia (iodide of ammonium), 1/2 dr.; simple ointment, 1 oz. Used chiefly as an application to scrofulous tumour and ulcers, in irritable subjects.

=Ointment of Hydrochlo′′ric Acid.= _Syn._ UNGUENTUM ACIDI HYDROCHLORICI, L. _Prep._ (Dr Corrigan.) Hydrochloric acid, 1 dr.; simple ointment, 1 oz. As a dressing for scald-head, after the scabs have been removed by emollient liniments or poultices.

=Ointment of Hypochlo′′rite of Lime.= _Syn._ OINTMENT OF CHLORIDE OF LIME; UNGUENTUM CALCIS HYPOCHLORITIS, U. C. CHLORINATÆ, L. _Prep._ 1. From chlorinated lime (chloride of lime), 1 dr.; lard, 1 oz.; carefully triturated together. In scrofulous swellings, goitre, chilblains, indolent glandular tumours, &c.

2. Chlorinated lime, 1 dr.; powdered foxglove, 2 dr.; simple ointment, 2 oz. As an application to fetid and malignant ulcers, &c.

=Ointment of Hypochlo′′rite of Sul′phur.= _Syn._ UNGUENTUM SULPHURIS HYPOCHLORITIS, L. _Prep._ (Dr Copland.) Hypochlorite of sulphur, 1 dr.; simple ointment, 1 oz. It is generally scented with oil of almonds. Used in psoriasis inveterata, and some other skin diseases.

=Ointment of I′odide of Ar′senic.= _Syn._ UNGUENTUM ARSENICI IODIDI, L. _Prep._ (Biett.) Iodide of arsenic, 2 to 3 gr.; lard, 1 oz.; carefully triturated together. In lepra, psoriasis, &c.; and in corroding tubercular diseases. It should be used with caution, and not more than 1/2 dr. applied at once.

=Ointment of Iodide of Ba′′rium.= _Syn._ UNGUENTUM BARII IODIDE, L. _Prep._ (Magendie.) Iodide of barium, 3 to 4 gr.; lard, 1 oz. As a friction to scrofulous swellings and indurations. The usual proportions are now 5 gr. to the oz.

=Ointment of Iodide of Iron.= (Pierquin.) _Syn._ UNGUENTUM FERRI IODIDI. _Prep._ Iodide of iron, 1 dr.; lard, 1 oz. Mix them.

=Ointment of Iodide of Lead.= _Syn._ UNGUENTUM PLUMBI IODIDI (B. P., Ph. L., & D.), L. _Prep._ 1. (Ph. L.) Iodide of lead, 1 oz.; lard, 8 oz.; rub them together.

2. (Ph. D.) Iodide of lead (in fine powder), 1 dr.; ointment of white wax, 7 dr.

3. (B. P.) Iodide of lead, in fine powder, 62 gr.; simple ointment, 1 oz. Mix. An excellent application to scrofulous tumours and swelled glands, especially when accompanied with pain.

=Ointment of Green Iodide of Mer′cury.= _Prep._ 1. (OINTMENT OF SUBIODIDE OF MERCURY, O. OF PROTIODIDE OF M.*; UNGUENTUM HYDRARGYRI IODIDI——Ph. L.) _a._ (Ph. L.) White wax, 2 oz.; lard, 6 oz.; melt them together, add of iodide (green iodide) of mercury, 1 oz., and rub them well together.

2. (Magendie.) Green iodide of mercury, 23 gr.; lard, 1-1/2 oz.

_Uses, &c._ In tubercular skin diseases, as a friction in scrofulous swellings and indolent granular tumours, and as a dressing for ill-conditioned ulcers, especially those of a scrofulous character.

=Ointment of Red Iodide of Mercury.= UNGUENTUM HYDRARGYRI IODIDI RUBRI, B. P., O. OF BINIODIDE OF M.*; UNGUENTUM HYDRARGYRI BINIODIDI,* U. H. IODIDI RUBRI——(Ph. D.)——1. (Ph. D.) Red iodide of mercury, 1 dr.; ointment of white wax, 7 dr.; mix by careful trituration.

2. (Soubeiran.) Red iodide of mercury, 20 gr.; lard, 1-1/2 oz.

3. (B. P.) Red iodide of mercury (in very fine powder), 16 gr.; simple ointment, 1 oz. Mix.

_Uses, &c._ Similar to those of the preceding, but it is much more stimulant, and is regarded as better adapted for obstinate syphilitic sores. Largely diluted with lard or almond oil, it is applied to the eyes in like cases.

=Ointment of Iodide of Potas′sium.= _Syn._ UNGUENTUM POTASSII IODIDI (B. P., Ph. L. & D.), L. _Prep._ 1. (Ph. L.) Iodide of potassium, 2 dr., dissolved in boiling distilled water, 2 fl. dr.; lard (softened by heat), 2 oz.; triturate together until united.

2. (Ph. D.) Iodide of potassium, 1 dr.; distilled water, 1/2 fl. dr.; ointment of white wax, 7 dr.; as before.

3. (Magendie.) Iodide of potassium, 1 dr.; lard, 12 dr.

4. (Le Gros.) Iodide, 1-1/2 dr.; lard, 1 oz.

5. (B. P.) Iodide of potassium, 64 gr.; carbonate of potash, 4 gr.; distilled water, 1 dr.; prepared lard, 1 oz.; dissolve the carbonate and the iodide in the water, and mix thoroughly with the lard.

_Uses, &c._ As a friction in scrofula, bronchocele, glandular enlargements, indurations, &c.; as a dressing to scrofulous ulcers, as an application in scrofulous ophthalmia, and in most of the other applications in which the employment of iodine is indicated. The last formula has been successfully employed by M. Le Gros in itch.

_Obs._ The strength of this ointment, as prescribed by different parties varies greatly, the proportions of the iodide ranging from 1/32 to 1/8 of the whole, to adapt it to particular cases. When other ingredients are added, the iodide must be used in a perfectly dry state, and in fine powder, instead of being dissolved in water. This is particularly necessary when it is to be mixed with mercurial ointment.

=Ointment of Iodide of Sulphur.= _Syn._ UNGUENTUM SULPHURIS IODIDI (B. P., Ph. L.), L. _Prep._ 1. (Ph. L.) Iodide of sulphur (in fine powder), 1/2 dr.; lard, 1 oz.; mix by trituration.

2. (Cazenave.) Iodide of sulphur, 12 to 15 gr.; lard, 1 oz.

3. (B. P.) Iodide of sulphur, 1; lard, 16. Mix.

_Uses, &c._ As a local stimulant and alterative in the chronic forms of lepra, lupus, porrigo, psoriasis, itch, &c.; also a remedy for acne punctata. A few drops of oil of cloves or nutmeg are commonly added.

=Ointment of Iodide of Zinc.= _Syn._ UNGUENTUM ZINCI IODIDI, L. _Prep._ 1. From iodide of zinc, 12 gr.; simple ointment, 1 oz. In scrofulous excoriations, and in the chronic ophthalmia of scrofulous subjects, arising from a relaxed state of the tissues and vessels.

2. (Dr Ure.) Iodide of zinc, 1 dr.; lard, 1 oz. As a friction to glandular tumours and indurations, and as a dressing to flabby and obstinate scrofulous ulcers.

=Ointment of I′odine.= _Syn._ UNGUENTUM IODI (B. P.), UNGUENTUM IODINII (Ph. U. S.). _Prep._ 1.——(B. P.) Iodine, 32 gr.; iodide of potassium, 32 gr.; proof spirit, 1 dr.; rub together and add prepared lard, 2 oz. See OINTMENT OF IODINE (Compound).

2. (Ph. U. S.) Iodine, 20 gr.; rectified spirit, 20 drops; rub them together, then add of lard, 1 oz.

=Ointment of Iodine (Compound).= _Syn._ OINTMENT OF IODURETTED IODIDE OF POTASSIUM; UNGUENTUM POTASSI IODIDI IODURETUM U. IODINII COMPOSITUM——Ph. L. & D., U. IODINII——Ph. E.——_a._ (Ph. L.) Iodine of potassium (in very fine powder), 1 dr.; lard, 2 oz.; mix, then add of iodine, 1/2 dr., dissolved in rectified spirit, 1 fl. dr., and mix all together. See OINTMENT OF IODINE (B. P.)

_b._ (Ph. E.) Iodine, 1 dr.; iodide of potassium, 2 dr.; rub them together, then gradually add of lard, 4 oz.

_c._ (Ph. D.) Pure iodine, 1/2 dr.; iodide of potassium, 1 dr.; rub them well together in a glass or porcelain mortar, then gradually add of ointment of white wax, 14-1/2 dr., and continue the trituration until a uniform ointment is obtained.

_Uses, &c._ The compound ointment is an excellent friction in goitre, and in enlarged or indurated glands or tumours, more especially those of a scrofulous character; in the quantity of 1/2 to 1 dr., night and morning. It may be advantageously combined with extract of belladonna in the incipient bubo of scrofulous subjects, and in the early stages of cancer; and, with an equal weight of mercurial ointment, as a friction in cases of enlarged liver and spleen, and ovarian dropsy. The simple ointment of the Ph. U. S. is generally regarded as weaker and less efficacious than the compound.

=Ointment of Iodo-chlo′′ride of Mercury.= _Syn._ UNGUENTUM HYDRARGYRI IODO-BICHLORIDI*, L. _Prep._ From iodo-chloride of Mercury, 16 gr.; simple ointment, 1 oz. Discutient; probably one of the most powerful known in syphilitic cases complicated with scrofula. See OINTMENT OF CHLORIODIDE OF MERCURY.

=Ointment of Iodoform= (Dr Glover). _Syn._ UNGUENTUM IODOFORMI. _Prep._ Iodoform 1/2 to 1 dram, simple cerate 8 drams. Mix.

=Ointment, Iodo-hydrar′gyrate of Potassa.= _Syn._ UNGUENTUM POTASSE IODO-HYDRARGYRATIS, L. _Prep._ 1. (Lamothe.) Iodo-hydrargyrate of potassa, 20 gr.; lard, 1 oz.

2. (Puche.) Red iodide of mercury and iodide of potassium, of each 8 gr.; lard, 1 oz. As a powerful stimulant discutient; in tumours, inflammatory sore throat, &c.

=Ointment, Iodo-narcot′ic.= _Syn._ UNGUENTUM IODO-NARCOTICUM, L. _Prep._ (Purvis.) Iodine, 20 gr.; iodide of potassium, 2 dr.; oil of tobacco (by infusion), 1-1/2 dr.; lard, 3 dr. To relax rigid muscles.

=Ointment of Ipecacuan′ha.= _Syn._ UNGUENTUM IPECACUANHÆ, L. _Prep._ (Dr. Turnbull.) Ipecacuanha (in fine powder), 2 dr.; olive oil, 2 fl. dr.; lard or simple ointment, 4 dr. Counter-irritant; when frequently employed as a friction, it occasions an eruption, but one of a milder character than that from either croton oil or tartar emetic.

=Ointment, Is′sue.= _Syn._ UNGUENTUM ADFONTICULOS, L. _Prep._ (Golding Bird.) Ointment of cantharides (Ph. L.), 1-1/2 oz.; tartar emetic (in impalpaple powder), 8 gr.; spermaceti ointment, 2 oz. As a stimulating application to issues, to promote the discharge. See ELEMI OINTMENT, CERATE, PLASTER, &c.

=Ointment, Itch.= _Syn._ UNGUENTUM ANTIPSORICUM, L. Several excellent formulæ for itch ointments will be found under the names of their leading ingredients. The following are additional ones, including some nostrums:——

1. (Bailey.) From alum, nitre, and sulphate of zinc, of each, in very fine powder, 1-1/4 oz.; vermilion, 1/2 oz.; mix, add gradually of sweet oil, 1/4 pint; triturate together until perfectly mixed, then further add of lard (softened by heat), 1 lb., with oils of aniseed, lavender, and origanum, q. s. to perfume.

2. (Bateman.) Carbonate of potassa, 1/2 oz.; rose water, 1 fl. oz.; red sulphuret of mercury, 1 dr.; oil of bergamot, 1/2 fl. dr.; sublimed sulphur, and hog’s lard, of each 11 oz.; mix them. (Bateman, ‘Cutaneous Diseases.’) The nostrum vended under the name is made as follows:——Carbonate of potash, 1 oz.; vermilion, 3 dr.; sulphur, 1 lb.; lard, 1-1/2 lb.; rose water, 3 fl. oz.; oil of bergamot, 1-1/2 dr.

3. (French Hosp.) Chloride of lime, 1 dr.; rectified spirit, 2 fl. dr.; sweet oil, 1/2 fl. oz.; common salt and sulphur, of each 1 oz.; soft soap, 2 oz.; oil of lemon, 20 drops. Cheap, effectual, and inoffensive.

4. (De la Harpe.) Sulphur, 2 oz.; powdered white hellebore, 1/2 oz.; sulphate of zinc, 1/4 do.; soft soap, 4 oz.; lard, 8 oz.

5. (Jackson.) From palm oil, flowers of sulphur, and white hellebore of each 1 part; lard, 2 parts.

6. (Nugent.) From white lead, 2 oz.; orris root, 1 oz.; corrosive sublimate, in very fine powder, 1/2 oz.; palm oil, 4 oz.; lard, 1-1/2 lb.

7. (Ph. E., 1744.) Elecampane root and sharp-pointed dock (_Rumex acutus_——Linn.), of each bruised, 3 oz.; water, 1 quart; vinegar, 3/4 pint; boil to one half, add of water-cress, 10 oz.; lard, 4 lb.; boil to dryness, and stain with expression; to the strained liquid add of beeswax and oil of bays, of each 4 oz.; and stir the mixture until nearly cold.

8. (UNG. A. COMP.——Ph. E. 1744.) To each lb. of the last add of strong mercurial ointment, 2 oz.

9. (Robertson.) Soft soap, 1 oz.; rum, 1 table-spoonful; chloride of lime (dry and good), 1/4 oz.; mix, and add of lard, 2 oz.

10. (Swediaur.) Stavesacre (in powder), 1 oz.; lard, 3 oz.; digest with heat for 3 hours, and then strain. The formula of the Ph. Bruns. is nearly similar. Very useful in itch; also to destroy pediculi.

11. (Thomson.) Chloride of lime and common salt, of each, in fine powder, 1 dr.; soft soap, 1 oz.; rectified spirit, 2 fl. dr.; mix, add of lard, 1 oz.; and, lastly, of strong vinegar, 3 fl. dr. Very cleanly and effective; but should not be made in quantity, as it does not keep well.

12. (Vogt.) Chloride of lime (dry), 2 dr.; burnt alum, 3 dr.; lard, 9 dr. To be mixed with an equal quantity of soft soap at the time of fusing it.

_Obs._ The products of the preceding formulæ are used by well rubbing them into the part affected, night and morning, as long as necessary, the number of applications required depending greatly on the manner in which this is done.

=Ointment of I′vy.= _Syn._ UNGUENTUM HEDERÆ, L. _Prep._ From the leaves of common ivy, by infusion, as ointment of henbane. Used as an application to soft corns, in itch, and as a dressing to indolent ulcers and tissues.

=Ointment of Jatropha= (PHYSIC-NUT). The milky juice of the English Physic nut (_Jatropha curcas_) mixed with half its weight of lard. In piles.

=Ointment of Juniper.= _Syn._ UNGUENTUM JUNIPERI. _Prep._ Juniper leaves, 1 part, resin ointment, 6 parts; boil gently and strain.

=Ointment of Ju′′niper-tar.= _Syn._ UNGUENTUM OLEI PYROLIGNI JUNIPERI, U. CADINUM, L. _Prep._ (Eras. Wilson.) Lard and suet, of each 6 parts; beeswax, 4 parts; liquefy by heat, and add of pyroligneous oil of juniper (‘huile de cade’) 16 parts; with a few drops of any fragrant essential oil, to conceal the smell. In ringworm, and as a stimulant ointment in some other skin diseases.

=Ointment, Kirkland’s.= See LEAD OINTMENT (Compound).

=Ointment of Labdanum.= (Quincy.) _Syn._ UNGUENTUM CRINISCUM. _Prep._ Labdanum, 6 dr.; bears’ grease, 2 oz.; powdered southernwood, 3 dr.; oil of mace, 1 dr.; balsam of Peru, 2 dr.

=Ointment of Lard.= _Syn._ UNGUENTUM ADIPIS, L. _Prep._ (Ph. L. 1788.) Prepared lard, 2 lbs.; melt, add of rose water, 3 fl. oz.; beat the two well together, then set the vessel aside, and when the whole is cold, separate the congealed fat. A simple emollient. See OINTMENT, ELDER.

=Ointment of Lau′rel.= _Syn._ LAURINE OINTMENT; UNGUENTUM LAURINUM, U. LAURI NOBILIS, L. _Prep._ 1. (Ph. Lusit.) Suet (softened by heat), 8 oz.; laurel oil (expressed oil of bay), 1 lb.; oil of turpentine, 1-1/2 oz. This is the ‘nervine balsam’ and ‘nervine ointment’ of the shops in the Peninsula, and in some other parts of Southern Europe. The Ph. Bat. 1805 added 1/2 oz. of rectified oil of amber.

2. (P. Cod.) Fresh bay leaves and berries (bruised), of each 1 lb.; lard, 2 lbs.; as hemlock ointment——Ph. L. Highly esteemed on the Continent as a stimulating friction, in bruises, strains, stiff joints, &c.; and in deafness.

3. (Trade.) From fresh bay leaves, 2 lbs.; bay berries, 1 lb.; neat’s-foot oil, 5 pints; boil as last; to the strained oil add, of lard suet, 3 lbs., true oil of bay, 1/4 lb., and allow it to cool very slowly, in order that it may ‘grain’ well. Sold for laurel ointment and common oil of bay.

=Ointment of Lavender= (Baume). _Syn._ OLEUM LAVANDULÆ. _Prep._ Lard, 2-1/2 lbs.; lavender flowers, 10 lbs.; white wax, 3 oz. Melt the lard, digest with 2 lbs. of the flowers for two hours, and strain; repeat this with fresh flowers till all are used; melt the ointment and leave it at rest to cool; separate the moisture and dregs, and melt the ointment with the wax.

=Ointment of Lead.= _Syn._ (UNGUENTUM PLUMBI, U. LITHARGYRI——P. Cod.) _Prep._ 1. Litharge, 3 oz.; distilled vinegar, 4 oz.; olive oil, 9 oz.; mix with heat, and stir until they combine. Camphor, morphia, and opium are common additions to lead ointment, when an anodyne effect is desirable.

2. (Compound; NEUTRAL OINTMENT, HIGGIN’S O., KIRKLANDS’ O.; UNGUENTUM NEUTRALE, U. PLUMBI COMPOSITUM——Ph. L.) Lead plaster, 2 lbs.; olive oil, 18 fl. oz.; mix by a gentle heat, and add of prepared chalk, 6 oz.; lastly, add of dilute acetic acid, 6 fl. oz., and stir well until the mass has cooled. As a dressing in indolent ulcers, “but its utility is doubtful.” (Dr Garrod.)

_Obs._ It will be observed that the College has already modified the old formula of this ointment. The vinegar is now the last ingredient added to the mass. “Gradually add the chalk, separately mixed with the vinegar, the effervescence being finished, and stir,” &c. (Ph. L. 1836.) See ACETATE OF LEAD, CARBONATE OF L., CHLORIDE OF L., IODIDE OF L.; EYE, GOULARD’S, LE MORT’S, and other OINTMENTS containing lead.

=Ointment, Le Mort’s.= Carbonate of lead, corrosive sublimate, litharge, and Venice turpentine, of each 1 oz.; alum, 1/2 oz.; lard, 1/2 lb.; vermilion, q. s. to colour.

=Ointment of Lu′puline.= _Syn._ UNGUENTUM LUPULINÆ, L. _Prep._ (Soubeiran.) Lupuline, 1 part; lard, 3 parts; digest by the heat of a water bath for 5 or 6 hours, and strain. As an anodyne dressing to cancerous ulcers, and as a friction to swollen and painful joints.

=Ointment of Lycopo′dium.= _Syn._ UNGUENTUM LYCOPODII, L. _Prep._ Lycopodium, 1 dr.; balsam of Peru, 1/2 dr.; simple ointment, 1 oz. In chaps and excoriations.

=Ointment of Mace.= _Syn._ UNGUENTUM MACIDIS, L. _Prep._ From mace (beaten to a paste) and palm oil, of each 1 lb.; purified beef marrow, 3 lbs.; gently melted together, and strained. Emollient and stimulant; chiefly used as a pomade for the hair. Sold for ‘common oil of mace.’

=Ointment of Marshmal′low.= _Syn._ UNGUENTUM ALTHÆÆ, DIALTHÆÆ, L. _Prep._ 1. (Ph. L. 1746.) Oil of mucilages, 2 lbs.; beeswax, 1/2 lb.; yellow resin, 3 oz.; melt them together, then add of Venice turpentine, 1/2 oz.; and stir the mixture until it concretes.

2. (Wholesale.) From palm oil, 1/2 lb.; yellow resin, 1-1/4 lb.; beeswax, 2-1/4 lbs.; pale linseed oil, 9 lbs. (say 1 gall.); melt together and stir until it is nearly cold.

_Uses, &c._ Emollient and stimulant; seldom used in regular practice, but in great repute amongst the common people. Linseed oil is now almost universally substituted for the oil of mucilages.

=Ointment of Master-wort.= _Syn._ POMMADE ANTI-CANCÉREUSE DE MILIUS; UNGUENTUM IMPERITORIÆ, L. _Prep._ (Beasley.) Powdered master-wort (_Imperatoria Ostruthium_), 1-1/2 oz.; tincture of master-wort, 1 oz.; lard, 2 oz.

=Ointment of Matico= (Mr Young). _Syn._ UNGUENTUM MATICO. _Prep._ Powdered matico, 3 drams; opium, 3 gr.; lard, 1 oz.

=Ointment, Mercu′′rial.= _Syn._ (Strong MERCURIAL OINTMENT, BLUE O., NEAPOLITAN O.; UNGUENTUM HYDRARGYRI——B. P., Ph. L. E. & D., U. H. FORTIUS, U. CÆRULEUM.) _Prep._ 1. (B. P.) Mercury, 16; prepared lard, 16; prepared suet, 1; rub together until metallic globules cease to be visible. See also OINTMENT, MERCURIAL (Compound).

2 (Ph. L. & E.) Mercury; 1 lb.; lard, 11-1/2 oz.; suet, 1/2 oz.; rub the mercury with the suet and a little of the lard, until globules are no longer visible; then add the remaining lard, and triturate altogether.

3. (Ph. D.) Pure mercury and lard, of each 1 lb.; as before.

_Pur., &c._ The ‘stronger mercurial ointment’ of the shops is usually made with a less quantity of mercury than that ordered by the Colleges, and the colour is brought up with finely ground blue black or wood charcoal. This fraud may be detected by its inferior sp. gr., and by a portion being left undissolved when a little of the ointment is treated first with ether or oil of turpentine, to remove the fat, and then with dilute nitric acid, to remove the mercury. When made according to the instructions of the Ph., its sp. gr. is not less than 1·781 at 60° Fahr. It “is not well prepared so long as metallic globules may be seen in it with a magnifier of 4 powers.” (Ph. E.) When rubbed on a piece of bright copper or gold, it should immediately give it a coating of metallic mercury, and a silvery appearance.

The _Ung. hyd. fort._ of the wholesale houses is generally made of mercury, 12 lbs., suet, 1-1/2 lb., and lard, 16-1/2 lbs. It thus contains only 1/3 instead of 1/2 its weight of mercury. That of the same houses labelled ‘_Ung. hyd. partes æquales_’ is prepared with mercury, 12 lbs.; suet, 1-1/2 lb.; lard, 13-1/2 lbs.

_Uses._ This ointment is chiefly used to introduce mercury into the system when the stomach is too irritable to bear it; in syphilis, hepatic affections, hydrocephalus, &c. For this purpose, 1/2 to 1 dr. is commonly rubbed into the inside of one of the thighs until every particle of the ointment disappears. This operation is repeated night and morning until the desired effect is produced, and should be, if possible, performed by the patient himself. During its administration the patient should avoid exposure to cold, and the use of fermented or acidulous liquors, and his diet should consist chiefly of toast, broth, gruel, milk-and-water, and other inoffensive matters. This ointment has been employed to prevent the ‘pitting’ in smallpox; and, diluted with 3 or 4 times its weight of lard, in several skin diseases, as a dressing for ulcers, to destroy pediculi, &c. Camphor is often added to this ointment to increase its activity. With the addition of a little extract of belladonna, or hydrochlorate of ammonia, it forms an excellent anodyne and resolvent friction in painful syphilitic tumours and glandular enlargements.

_Obs._ The preparation of mercurial ointment according to the common plan is a process of much labour and difficulty, and usually occupies several days. The instructions in the Pharmacopœias are very meagre and unsatisfactory, and, so far as details go, are seldom precisely carried out. Employers grumble, and operatives become impatient, when they find the most assiduous trituration apparently fails to hasten the extinction of the globules. To facilitate matters, various tricks are resorted to, and various contraband additions are often clandestinely made. Among the articles referred to, sulphur and turpentine are those which have been longest known, and, perhaps, most frequently employed for the purpose; but the first spoils the colour, and the other the consistence, of the ointment; whilst both impart to it more or less of their peculiar and respective odours. On the Continent, oil of eggs was formerly very generally used for the purpose, and is even now occasionally so employed. Nearly half a century ago Mr W. Cooley clearly showed that the difficulty might be satisfactorily overcome by simply triturating the quicksilver with 1/8 to 1/4 of its weight of old mercurial ointment, before adding the lard; and that the effective power of this substance was in direct proportion to its age, or the length of time it had been exposed to the air. His plan was to employ the ‘bottom’ and ‘scraping’ of the store pots for the purpose. At a later period (1814-15) Mr Higginbottom, of Northampton, repeated this recommendation, and at length the plan has been imported into the Pharmacopœia Borussica. About twenty years since, “we reopened an investigation of the subject, which extended over several months, during which we satisfied ourselves of the accuracy of the assertion of M. Roux, that the mercury in mercurial ointment exists entirely, or nearly so, in the metallic state, and not in the form of oxide, as was generally assumed. We succeeded in preparing an excellent sample of mercurial ointment by agitating washed suet and quicksilver together _in vacuo_. The quantity of oxide present at any time in this ointment is variable and accidental, and is largest in that which has been long prepared; but in no case is it sufficient to materially discolour the fat after the metallic mercury is separated from it. We were led to conclude that the property alluded to, possessed by old ointment, depends solely on the peculiar degree of consistence or viscidity of the fat present in it, and on the loss of much of the thoroughly greasy, ‘anti-attritive’ character, possessed by the latter in a recent state. In practically working out this idea we obtained pure fats (MAGNETIC ADEPS; SEVUM PRÆPARATUM), which, without any addition, were capable of reducing, in a few minutes, 8, 16, 32, and even 48 times their weight of mercury. We also found that the formula of the Pharmacopœia might be adopted, and that a perfect ointment might be readily obtained by skilful management in from half an hour to an hour, even without these resources. All that was necessary was to employ a very gentle degree of heat by either performing the operation in a warm apartment or by allowing the mortar to remain filled with warm water for a short time before using it. Suet or lard, reduced either by gentle warmth or by the addition of a little almond oil to the consistence of a thick cream, so that it will hang to the pestle without running from it, will readily extinguish 7 or 8 times its weight of running mercury by simple trituration. The exact temperature must, however, be hit upon, or the operation fails. This fact was afterwards noticed in the ‘Ann. de Chim.,’ and some other journals.” (A. J. Cooley.)

M. Pomonti has proposed a method of preparing strong mercurial ointment, which, modified to suit the English operator, is as follows:——Fresh lard, 8 parts; solution of nitre (see _below_), 1 part; mix by trituration, add of mercury, 32 parts, and again triturate. The globules disappear after a few turns of the pestle, but reappear in a few minutes, and then again disappear to return no more. When this happens, the trituration is to be continued for a few minutes longer, when lard, 24 parts, is to be rubbed in, and the ointment at once put into pots. It is said that the globules are so completely extinguished as to escape detection, even when the ointment is examined by a microscope of low power. The SOLUTION.——Nitre, 100 gr.; water, 1 fl. oz.; dissolve. This quantity is sufficient for a kilogramme of mercury.

M. Lahens strongly recommends for the rapid preparation of mercurial ointment the application of oil of almonds in the following proportions:——Mercury, 1000 parts; oil of almonds, 20 parts; lard, 980 parts. The mercury is first triturated with the oil for about fifteen minutes, after which its globules are said to be no longer discernible by the naked eye; 200 parts of the melted lard are now added, and the trituration continued to the complete extinction of the metal, which is generally accomplished within an hour. The ointment is then mixed with the remainder of the lard. SEE OINTMENT OF OXIDE OF MERCURY.

=Ointment, Mercurial= (Milder). MILDER BLUE OINTMENT, TROOPER’S O., UNCTION; UNGUENTUM HYDRARGYRI MITIUS, U. CÆRULEUM MITIUS. _Prep._ 1. Stronger mercurial ointment, 1 lb.; lard, 2 lbs.

_Dose, &c._ In the itch and several other cutaneous diseases, as a dressing to syphilitic ulcers, to destroy pediculi on the body, &c. Each drachm contains 10 gr. of mercury. That of the shops generally contains considerably less.

2. (With SOAP; UNGUENTUM HYDRARGYRI SAPONACEUM; SAVON MERCURIEL).——_a._ (Draper.) Mercurial ointment (softened by a gentle heat), 1 oz.; hydrate of potassa, 1 dr., dissolved in water, 1/2 fl. oz.; triturate them together until the mass solidifies.

_b._ (Swediaur.) Milder mercurial ointment, 8 parts; soft soap, 2 parts; camphor, 1 part. In periostitis, engorgements of the testicles, soft corns, &c. See OINTMENT OF NITRATE OF MERCURY, &c.

=Ointment, Mercurial (Compound).= (B. P.) Mercurial ointment, 6; yellow wax, 3; olive oil, 3; camphor, 1-1/2. Melt the wax and oil, and when the mixture is nearly cold, add the camphor in powder and the mercurial ointment, and mix.

=Ointment, Mercurial, with Hydrochlorate of Ammonia.= (Dupuytren.) _Syn._ UNGUENTUM HYDRARGYRI CUM AMMONIÆ MURIATE. _Prep._ Stronger mercurial ointment, 2 oz.; hydrochlorate of ammonia, 1 dr.

=Ointment, Mercurial, with Soda.= (F. H.) _Syn._ UNGUENTUM HYDRARGYRI CUM SODA, SAVON MERCURIEL. _Prep._ Mercurial ointment, 3-1/2 oz.; solution of soda, 3 oz.; triturate until they combine.

=Ointment of Mercury, Oleate of.= (U. C. Hosp.) _Syn._ LINIMENTUM HYDRARGYRI OLEATIS, UNGUENTUM HYDRARGYRI OLEATIS. (10 per cent.) _Prep._ Yellow peroxide of mercury, 1 dr.; pure oleic acid, 10 dr. To the oleic acid kept agitated in a mortar, sprinkle in the peroxide gradually, and triturate frequently during 24 hours, until the peroxide is dissolved, and a gelatinous solution is formed, 20 per cent. as above, using double the quantity of yellow oxide. To be applied with a brush, or spread lightly over the part with the finger. In persistent inflammation of the joints, Professor Marshall adds to ʒj of the above preparation, 1 gr. of morphia——the pure alkaloid——not one of its salts, which are insoluble in oleic acid.

In the preparation of ointment of oleate of mercury it is of the utmost importance that the mercuric oxide should be thoroughly dry, and further that it should be sifted in small portions at a time upon the surface of the oleic acid, each fresh portion being well incorporated before another is added. Solution should be promoted by frequent stirring, at ordinary temperatures, since experience has shown that all heating is positively injurious.[66]

[Footnote 66: C. Rice.]

=Ointment of Mercury, Yellow Oxide of.= (U. S. Ph.) _Syn._ UNGUENTUM HYDRARGYRI, =Oxydi flavi=. _Prep._ Yellow oxide of mercury, 1 dr.; simple ointment, 420 gr.

=Ointment of Meze′reon.= _Syn._ UNGUENTUM MEZEREI, L. _Prep._ 1. (Hamb. Cod.) Alcoholic extract of mezereon, 2 dr.; dissolve in rectified spirit, q. s.; add it to white wax, 1 oz.; lard, 8 oz., and mix by a gentle heat.

2. (P. Cod.) Mezereon (dried root-bark), 4 oz.; moisten it with rectified spirit, bruise it well, and digest it for 12 hours, at the heat of boiling water, in lard, 14-1/2 oz.; then strain with pressure, and allow it to cool slowly; lastly, separate it from the dregs, remelt it, and add of white wax, 1-1/2 oz. Used as a stimulating application to blistered surfaces and indolent ulcers.

3. (P. Cod.) Ethereal extract of mezereon, 176 gr.; lard, 9 oz.; white wax, 1 oz.; rectified spirit, 1 oz.; dissolve the extract in the alcohol, add the lard and wax, heat moderately, stir until the spirit is driven off, strain and stir till cold.

=Ointment of Monesia.= _Syn._ UNGUENTUM MONESIÆ. _Prep._ Oil of almonds, 4 parts; white wax, 2 parts; extract of monesia, 1 part; water, 1 part.

=Ointment of Mustard.= _Syn._ UNGUENTUM SINAPIS, L. _Prep._ 1. Flour of mustard, 3/4 oz.; water, 1 fl. oz.; mix, and add, of resin cerate, 2 oz; oil of turpentine, 1/2 oz. Rubefacient and stimulant. As a friction in rheumatism, &c.

2. (Frank.) Flour of mustard, 3 oz.; oil of almonds, 1/2 fl. oz.; lemon juice, q. s. In sunburn, freckles, &c.

=Ointment of Naph′thalin.= _Syn._ UNGUENTUM NAPHTHALINÆ, L. _Prep._ (Emery.) Naphthalin, 1/2 dr.; lard, 7-1/2 dr. In dry tetters, lepra, psoriasis, &c.

=Ointment, Neapolitan.= See OINTMENT, MERCURIAL.

=Ointment, Nervine.= _Syn._ BALSAMUM NERVINUM, UNGUENTUM N., L.; BAUME NERVAL, Fr. _Prep._ (P. Cod.) Expressed oil of mace and ox marrow, of each 4 oz.; melt by a gentle heat, and add, of oil of rosemary, 2 dr.; oil of cloves, 1 dr.; camphor, 1 dr.; balsam of tolu, 2 dr.; (the last two dissolved in) rectified spirit, 4 dr. In rheumatism, &c. A somewhat similar preparation was included in the Ph. E. 1744.

=Ointment, Narcotic and Balsamic= (G. Ph.). _Syn._ UNGUENTUM NARCOTICO-BALSAMICUM HELLMUNDI. _Prep._ Acetate of lead, 10 drams; extract of hemlock, 30 drams; wax ointment, 33 oz.; balsam of Peru, 30 drams; wine of opium, 5 drams.

=Ointment, Neu′tral.= See OINTMENT OF LEAD (Compound).

=Ointment of Ni′trate of Mercury.= _Syn._ CITRINE OINTMENT, YELLOW O., MERCURIAL BALSAM; UNGUENTUM HYDRARGYRI NITRATIS (B. P., Ph. L. & D.), U. H. N., or U. CITRINUM (Ph. E.), L. _Prep._ 1. (Ph. L.) Mercury, 2 oz.; nitric acid (sp. gr. 1·42), 4 fl. oz.; dissolve and mix the solution, whilst still hot, with lard, 1 lb., and olive oil, 8 fl. oz., melted together. (For the MILDER OINTMENT, see _below_.)

2. (Ph. E.) Mercury, 4 oz.; nitric acid (sp. gr. 1·500), 8 fl. oz. 6 fl. dr.; dissolve by a gentle heat, add the liquid to lard, 15 oz,; olive oil, 32 fl. oz.; melted together, and whilst the whole are still hot, and mix them thoroughly. “If the mixture does not froth up, increase the heat a little until this takes place. Keep the ointment in earthenware vessels, or glass vessels, secluded from the air.” This admirable formula is a modification of that originally introduced into Pharmacy by the late Dr Duncan, of Edinburgh. (For the milder ointment, see _below_.)

3. (Ph. D.) Mercury 1 oz.; nitric acid, (1·500), 1 fl. oz.; (diluted with) water, 1/2 fl. oz.; dissolve by a gentle heat, and add the liquid to lard, 4 oz.; olive oil, 8 fl. oz.; melted together, and still hot; next “let the temperature of the mixture be raised so as to cause effervescence, and then, withdrawing the heat, stir the mixture with a porcelain spoon until it concretes on cooling.”

4. (P. Cod.) Mercury, 3 parts; nitric acid (1·321), 6 parts; lard and oil, of each 24 parts; as above.

5. (Ph. U. S.) Mercury, 1 oz.; nitric acid (1·42), 14 fl. oz.; lard, 3 oz.; fresh neat’s-foot oil, 9 fl. oz.; mix the mercurial solution with the melted fat and oil at 200° Fahr.

6. (B. P.) Mercury, 4; nitric acid, 12; prepared lard, 15; olive oil, 32; dissolve the mercury in the nitric acid with the aid of a gentle heat; melt the lard in the oil by a steam or water bath in a porcelain vessel capable of holding six times the quantity, and while the mixture is hot add the solution of mercury, also hot, and mix them together thoroughly. If the mixture does not froth up, increase the heat till this occurs. (The heat required for this is from 170° to 180° Fahr.)

_Uses, &c._ Detergent and stimulant. In ringworm, herpes, itch, porrigo, psoriasis, and some other chronic skin diseases; in various chronic affections of the eyes, especially chronic inflammation and ulceration of the eyelids, ‘blear eye,’ &c. It “may almost be regarded as specific in psorophthalmia, in the purulent ophthalmia of infants producing ectropium (eversion of the eyelids), and in ulcerations of the tarsi (edges of the eyelids).” (A. T. Thomson.) As a dressing to old ulcers, more especially those of a syphilitic character, it is superior to all the other ointments containing mercury; in sore legs, assisted by the internal use of the pill of soap with opium (PIL SAPONIS CUM OPIO), it often acts like a charm when all other modes of treatment have failed. For most of these purposes it should be diluted with from twice to seven times its weight of some simple fatty matter. One of the principal reasons why this ointment is in less general use than its merits deserve, is the very inferior quality of that vended in the shops under the name, arising from almost every druggist preparing some mess of his own, instead of adhering to the College formulæ.

_Obs._ Ointment of nitrate of mercury, faithfully prepared according to the instructions in the Pharmacopœia, possesses a rich golden-yellow colour, and a buttery consistence, and keeps well. Unfortunately, clumsy and careless operators, who regard the Pharmacopœia as a foolish book, which it is quite unnecessary to look into, often fail in their attempts to produce an article of good quality. The difficulty is immediately surmounted by employing pure ingredients, in the proportions ordered, and mixing them at the proper temperature. The acid should be of the full strength, or, if somewhat weaker than that directed, an equivalent quantity should be employed. A slight excess of acid is not injurious, rather the contrary; but a deficiency of acid, in all cases, more or less damages the quality of the product. If, on stirring the mercurial solution with the melted lard and oil, the mixture does not froth up, the heat should be increased a little, as, unless a violent frothing and reaction take place, the ointment will not turn out of good quality, and will rapidly harden and lose its colour. The most favorable temperature for the union of the ingredients is from 185° to 200° Fahr., and in no case should it exceed 212°; whilst below 180° Fahr., the reactions are feeble and imperfect.

Stoneware or glass vessels must alone be employed in the preparation of this ointment, and the stirrers or spatulas should be either of glass or white deal. The best plan is to keep the whole exclusively for the purpose, and when out of use to preserve them from dust and dirt. (See _below_.)

=Ointment of Ni′trate of Mercury.= (Milder.) _Syn._ MILDER CITRINE OINTMENT; UNGUENTUM HYDRARGYRI NITRATIS MITIUS (Ph. L.), U. H. N. M., Or U. CITRINUM M. (Ph. E.), L. _Prep._ 1. (Ph. L.) Ointment of nitrate of mercury, 1 oz.; lard, 7 oz.; rub them together. “This ointment is to be used recently prepared.”

2. (Ph. E.) As the stronger ointment, Ph. E., but using a triple proportion of oil and lard. _Uses, &c._ See the STRONGER OINTMENT (_above_).

=Ointment of Ni′trate of Sil′ver.= _Syn._ UNGUENTUM ARGENTI NITRATIS, L. _Prep._ 1. (M. Jobert.) Nitrate of silver, 2, 4, or 6 parts; lard, 20 parts. These ointments are respectively numbered 1, 2, and 3, and are used in white-swelling.

2. (Macdonald.) Nitrate of silver, 1 part; lard, 7 to 8 parts. To smear bougies, in gonorrhœa, &c.

3. (Mackenzie.) Nitrate of silver, 5 gr.; lard, 1 oz. In purulent and chronic ophthalmia, ulcers on the cornea, &c.

4. (Velpeau.) Nitrate of silver, 1 gr.; lard, 1 dr. In acute ophthalmia, &c. The above compounds require to be used with caution.

=Ointment of Ni′tric Acid.= _Syn._ OXYGENISED FAT†; UNGUENTUM OXYGENATUM, U. A. NITRICI, L.; POMMADE D’ALYON, Fr. _Prep._ (Ph. D. 1826.) Olive oil, 1 lb.; lard, 4 oz.; melt them together, add, gradually, of nitric acid (sp. gr. 1·500), 5-1/2 fl. dr., and stir the mixture constantly with a glass rod until it concretes.

_Uses, &c._ In itch, porrigo, and some other chronic skin diseases; and as a dressing for syphilitic and herpetic ulcers, old sores, &c. It is frequently employed as a substitute for the ointment of nitrate of mercury, which it somewhat resembles in appearance; but it is less active and useful.

=Ointment of Ni′tric Ox′ide of Mer′cury.= _Syn._ OINTMENT OF RED OXIDE OF MERCURY (B. P.), RED PRECIPITATE OINTMENT; UNGUENTUM HYDRARGYRI NITRICO-OXYDI (Ph. L.), U. H. OXYDI (Ph. E.), U. H. O. RUBRI (B. P., Ph. D.), L. _Prep._ 1. (Ph. L.) White wax, 2 oz.; lard, 6 oz.; mix, by heat, add of nitric oxide of mercury, in very fine powder, 1 oz., and rub them together.

2. (Ph. E.) Nitric oxide of mercury, 1 oz.; lard, 8 oz.; mix by trituration.

3. (Ph. D.) Red oxide of mercury (nitric oxide), 1 dr.; ointment of white wax, 7 dr.; as the last.

4. (B. P.) Red oxide of mercury, in very fine powder, 62 gr.; yellow wax, 1/4 oz.; oil of almonds, 3/4 oz.; melt the wax, add the oil, and mix.

_Uses, &c._ An excellent stimulant application to indolent and foul sores, ulcers, &c.; and, when diluted, as an eye ointment in chronic inflammation and ulceration of the eyes and eyelids, and especially in psorophthalmia; also in specks on the cornea, and the other affections noticed under OINTMENT OF NITRATE OF MERCURY. It forms the basis of numerous quack medicines. See also OINTMENT OF OXIDE OF MERCURY (_below_).

=Ointment, Obstet′ric.= _Syn._ UNGUENTUM OBSTETRICUM, L.; POMMADE OBSTETRICALE, Fr. _Prep._ 1. (Chaussier.) Extract of belladonna, 1 dr.; water, 2 dr.; lard, 1 oz. To promote the dilatation of the os uteri.

2. (POMMADE POUR LE TOUCHER.) From yellow wax and spermaceti, of each 1 oz.; olive oil, 16 oz.; melt them together, strain, add of solution of caustic soda, 1 fl. oz., and stir until the whole is nearly cold.

=Ointment of O′pium.= _Syn._ UNGUENTUM OPIATUM, U. OPII (Ph. L.), L. _Prep._ 1. (Ph. L.) Powdered opium, 20 gr.; lard, 1 oz.; mix by trituration. As a simple anodyne friction or dressing.

2. (Augustin.) Opium, 2 dr.; ox-gall, 2 oz.; digest 2 days, strain, and add, of melted lard, 2 oz.; oil of bergamot, 10 drops.

3. (Brera.) Opium, 1 dr.; gastric juice of a calf, 1/2 oz.; digest 24 hours, and add of melted lard, 1 oz.

=Ointment of Oxide of Lead.= See OINTMENT, LEAD.

=Ointment of Oxide of Man′′ganese.= _Syn._ UNGUENTUM MANGANESII OXYDI, U. M. BINOXYDI, L. _Prep._ 1. Black oxide of manganese (levigated), 1 dr.; lard, 1 oz.; mix by patient trituration. As a friction in scrofulous swellings and indurations; and in itch, scald-head, chilblains, &c.

2. (W. Cooley.) Binoxide of manganese, 1 dr.; sulphur, 2 dr.; lard, 9 dr.; cajeput oil, 15 drops. As the last; also as a friction in rheumatism, swelled joints, &c., and in porrigo, and some other skin diseases.

=Ointment of Oxide of Mer′cury.= Under this name the two ointments noticed below are often confounded, owing to the different opinions held respecting the atomic weight of mercury:——

1. =Ointment of Grey Oxide of Mer′cury.= _Syn._ OINTMENT OF SUBOXIDE OF MERCURY, O. OF PROTOXIDE OF M.†; UNGUENTUM HYDRARGYRI OXYDI, U. H. SUBOXYDI, U. H. O. CINEREI, L. _Prep._ 1. (Ph. E. 1817.) Grey oxide of mercury, 1 oz.; lard, 3 oz.; triturate together. Formerly proposed as a substitute for mercurial ointment, but in practice it has been found useless as a friction, owing to the unctuous matter only being absorbed, whilst the oxide is left on the surface. This objection does not apply to the following preparations:——

2. (Donovan.) Grey oxide of mercury, 20 gr.; lard, 1 oz.; mix, and expose them to the temperature of 320° Fahr. for 2 hours, constantly stirring. Grey coloured. It may also be made from the nitric- or red-oxide in the same way, by keeping the ointment heated to about 300° for some hours. Cleaner and stronger than Ung. hyd. fort.——Ph. L.

3. (Tyson.) Black oxide of mercury (prepared by decomposing precipitated calomel with liquors of potassa and ammonia), 2 oz.; lard, 1 lb.; triturate together. Inferior in activity to the last. It closely resembles in appearance a fine sample of mercurial ointment.

2. =Ointment of Red Oxide of Mercury.= _Syn._ UNGUENTUM HYDRARGYRI BINOXIDI†, U. H. OXYDI RUBRI, L. _Prep._ (Cazenave.) Red oxide of mercury, 30 gr.; camphor, 5 gr.; lard, 1 oz. Closely resembles ointment of nitric oxide of mercury, over which it, perhaps, possesses some advantage from the oxide being in a more minutely divided state.

=Ointment of Oxide of Sil′ver.= UNGUENTUM ARGENTI OXYDI, L. _Prep._ (Serre.) OXIDE OF SILVER, 16 to 20 gr.; lard, 1 oz. As a dressing for scrofulous and syphilitic sores, &c.

=Ointment of Oxide of Zinc.= _Syn._ ZINC OINTMENT; NIHIL ALBUM OINTMENT†; UNGUENTUM ZINCI (B. P., Ph. L., E., & D.), U. OXYDI ZINCI, L. _Prep._ 1. (Ph. L.) Oxide of zinc, 1 oz.; lard, 6 oz.; mix them together.

2. (Ph. E.) Oxide of zinc, 1 oz.; simple liniment (Ph. E.), 6 oz.

3. (Ph. D.) Ointment of white wax, 12 oz.; melt it by a gentle heat, add of oxide of zinc, 2 oz.; and stir constantly until the mixture concretes.

4. (B. P.) Oxide of zinc, in very fine powder, 1; benzoated lard, 5-1/2; mix.

_Uses, &c._ Astringent, desiccative, and stimulant; in excoriations, burns, various skin diseases attended by profuse discharges, in chronic inflammation of the eyes depending on relaxation of the vessels, in sore nipples, indolent sores, ringworm of the scalp, &c. It is an excellent and very useful preparation. See OINTMENT, TUTTY (_below_).

=Ointment of Pep′per.= _Syn._ UNGUENTUM PIPERIS NIGRI, L. _Prep._ 1. Black pepper (bruised), 1 oz.; lard, 2 oz.; suet, 1 oz.; digest together in a covered vessel, by the heat of a water bath, for six hours, then strain, with pressure, add of expressed oil of mace, 2 dr., and stir until the mixture concretes. In piles, itch, as a friction in rheumatism, &c.

2. (Ph. D. 1826.) Black pepper (in fine powder), 4 oz.; lard, 1 lb.; mix. In scald-head, &c.

=Ointment of Phosphor′ic Acid.= _Syn._ UNGUENTUM ACIDI PHOSPHORICI, L. _Prep._ (Soubeiran.) Phosphoric acid, 1 dr.; lard (softened by heat), 1 oz; triturate carefully together. As a friction in caries, osseous tumours, &c.

=Ointment of Phos′phorus.= _Syn._ UNGUENTUM PHOSPHORI, U. PHOSPHORATUM, L. _Prep._ (P. Cod.) Phosphorus, 1 dr.; lard, 6 oz. 3 dr.; melt together (in a wide-mouthed bottle) by the heat of a water bath, remove the vessel from the heat, and shake it briskly until the ointment concretes. As a friction in gout, chronic rheumatism, and several skin diseases.

=Ointment of Picrotox′in.= _Syn._ UNGUENTUM PICROTOXINÆ, L. _Prep._ (Jäjer.) Picrotoxin, 10 gr.; lard, 1 oz. In ringworm of the scalp, and to destroy pediculi. It should be used with care.

=Ointment for Piles.= _Syn._ UNGUENTUM HÆMORRHOIDALE, U. ANTI-HÆMORRHOIDALE, L. _Prep._ 1. Burnt alum and oxide of zinc, of each 1/2 dr.; lard, 7 dr.

2. (Bories.) Acetate of lead, 15 gr.; freshly burnt cork, 1/2 oz.; washed fresh butter, 2 oz.; triturate well together.

3. (W. Cooley.) Morphia, 8 gr.; melted spermaceti ointment, 1 oz.; triturate together until solution is complete, then add, of galls (in impalpable powder), 1-1/2 dr., essential oil of almonds (genuine crude), 12 to 15 drops, and stir until the mass concretes. In painful piles, prolapsus, &c. It is not only very effective, but does not soil the linen so much as most other ointments.

4. (Dr Gedding.) Carbonate of lead, 4 dr.; sulphate of morphia, 15 gr.; stramonium ointment, 1 oz.; olive oil, q. s. When there is much pain and inflammation.

5. (Sir H. Halford.) Ointment of nitrate of mercury and oil of almonds, equal parts, triturated together.

6. (Mazzini.) Nitrate of morphia, 15 gr.; citrine ointment, 1 dr.; fresh butter, 1 oz. As the last.

7. (Vallez.) Extract of elder leaves, 1/2 dr.; burnt alum, 16 gr.; poplar ointment, 1 oz. For other formulæ, see the respective names of their leading ingredients.

8. (Ware.) Camphor, 1 dr.; simple ointment, 1 oz.; dissolve by heat, add of powdered galls, 2 dr.; mix well, further add of tincture of opium, 2 fl. dr., and stir until the whole is cold. In flabby mucous and painful piles.

9. (Zanin.) Spermaceti ointment, 1 oz.; powdered galls, 1 dr.; powdered opium, 18 gr.; solution of diacetate of lead, 1 fl. dr. When there is both pain and inflammation.

10. (From New Remedies.) Yellow wax, 8 parts; resin, 4 parts; lard, 12 parts; oil of sassafras, 2 parts. Melt the wax, resin, and lard, remove from the fire, add the oil of sassafras, and stir until the mass is solid. This is said to be a most excellent application for painful or itching piles.

=Ointment of Pitch.= _Syn._ BLACK BASILICON, OINTMENT OF BLACK PITCH; UNG. PICIS (B. P., Ph. L.), U. PICIS NIGRÆ, L. _Prep._ 1. (Ph. L.) Black pitch, resin, and beeswax, of each 11 oz.; olive oil, 1 pint; melt together, strain through a linen cloth (and stir until the mass concretes).

2. (B. P.) Tar, 5; yellow wax, 2; melt together, and stir till cold.

_Uses, &c._ Stimulant and detergent; very useful in indolent ulcerations, scald-head, and various foul eruptions. In itch and psoriasis, and other scaly skin diseases, a little sulphur is commonly added to it.

=Ointment of Plat′inum.= _Syn._ UNGUENTUM PLANTINI, L. _Prep._ (Hœfer.) Bichloride of platinum, 15 gr.; extract of belladonna, 1/2 dr.; lard, 1 oz. As a dressing for painful indolent ulcers.

=Ointment of Plumbago.= _Syn._ OINTMENT OF GRAPHITE; UNGUENTUM GRAPHITIS, U. PLUMBAGINIS, L. _Prep._ From pure plumbago (‘black-lead’), 1-1/2 dr.; lard, 1 oz. As a dressing to ulcers, and in certain skin diseases.

=Ointment, Plunket’s.= _Prep._ (Original formula.) Crowsfoot, 1 handful; dog’s fennel, 3 sprigs; pound well, add of flowers of sulphur and white arsenic, of each 3 thimblefuls; beat them well together, form the mass into boluses, and dry them in the sun. For use, powder them; and mix the powder with yolk of egg, spread a little on a small piece of pig’s bladder (size of half a crown), and apply it to the sore, where it must remain until it falls off by itself. Poisonous; in cancer; with great caution.

=Ointment, Poma′tum.= See OINTMENT, LARD.

=Ointment of Pop′lar Buds.= _Syn._ UNGUENTUM POPULEUM, L. _Prep._ 1. Fresh poplar buds (bruised), 1 part; lard, 4 parts; boil until crisp, and strain. It never gets rancid. Emollient and stimulant.

2. (Compound——P. Cod.) Poplar buds, 12 oz.; fresh leaves of belladonna, common nightshade (_Solanum nigrum_), henbane, and poppies, of each 8 oz.; lard, 4-1/2 lbs.; as the last. Emollient, stimulant, and anodyne.

=Ointment of Potas′sio-tar′trate of An′timony.= _Syn._ ANTIMONIAL OINTMENT, TARTAR EMETIC O.; UNGUENTUM ANTIMONII TARTARATI (B. P.), UNGUENTUM ANTIMONII POTASSIO-TARTATRIS (Ph. L.), U. A. TARTARIZATI (Ph. D.), U. ANTIMONIALE (Ph. E.), U. TARTARI EMETICI, L. _Prep._ 1. (Ph. L. & E.) Potassic tartrate of antimony, rubbed to a very fine powder, 1 oz.; lard, 4 oz.; mix by trituration.

2. (Ph. D.) Tartar emetic, in very fine powder, 1 dr.; ointment of white wax, 7 dr.

3. (B. P.) Tartrated antimony (in fine powder), 1; simple ointment, 4. Mix.

_Uses, &c._ Counter-irritant; in phthisis, chronic rheumatism, certain liver affections, and other deep-seated pains and diseases. A portion about the size of a nut is rubbed on the skin night and morning, until a crop of pustules is produced. The part should be well rubbed with a coarse towel, so as to be reddened, before applying the ointment. The product of the Dublin formula is of only half the strength of those of the other Colleges.

_Obs._ Before adding the tartar emetic to the lard it should be reduced to the state of an impalpable powder. The precipitated salt is the best for this purpose. As the pustules formed by this ointment permanently mark the skin, it should only be applied to those parts of the person which are covered by the dress.

=Ointment, Pur′gative.= See OINTMENT OF COLOCYNTH, WORM O., &c.

=Ointment of Quinine′.= _Syn._ UNGUENTUM QUINIÆ, U. QUINIÆ SULPHATIS, L. _Prep._ 1. Sulphate of quinine, 1 dr.; lard, 3 dr. In the agues of children.

2. (Beasley _ex_ Antonini.) Sulphate of quinine, 1 dr.; alcohol (rectified spirit), 2 dr.; sulphuric acid, 10 drops; dissolve, and mix it with lard, 1/2 oz. In malignant intermittents; 2 to 4 dr. at a time, rubbed into the groin or axilla.

=Ointment of Red Sul′phuret of Mer′cury.= _Syn._ UNGUENTUM HYDRARGYRI BISULPHURETI, U. H. SULPHURETI RUBRI, L. _Prep._ 1. (Alibert.) Red sulphuret of mercury, 1 dr.; camphor, 20 gr.; simple ointment, 1 oz. In herpes, applied twice a day.

2. (Collier.) Bisulphuret of mercury, 1-1/2 dr.; sal ammoniac, 1/2 dr.; lard, 1 oz.; rose water, 1 fl. dr. In several skin diseases, to diminish the itching, destroy pediculi, &c.

3. (Radius.) As the last, with 1 oz. more lard.

=Ointment of Res′in.= _Syn._ YELLOW BASILICON; UNGUENTUM RESINÆ (Ph. D.), U. RESINOSUM (Ph. E.), L. _Prep._ 1. (Ph. D.) Yellow wax, 1/4 lb.; yellow resin, in coarse powder, 1/2 lb.; prepared lard, 1 lb.; melt them together by a gentle heat, strain the mixture, whilst hot, through flannel, and stir it constantly until it concretes.

2. (Ph. E.) Beeswax, 2 oz.; resin, 5 oz.; lard, 8 oz.

_Obs._ A useful stimulant dressing to foul and indolent ulcers. For the corresponding preparation of the Ph. L., see CERATE, RESIN.

=Ointment, Resol′vent.= See OINTMENT, DISCUTIENT.

=Ointment of Rhatany= (Trousseau). _Syn._ UNGUENTUM RHATTINIÆ. _Prep._ Extract of rhatany, 1-1/2 dr.; cacao butter, 5 dr. Mix.

=Ointment, Ring′worm.= UNGUENTUM CONTRA-TINEAM, L. _Prep._ 1. Carbonate of soda, 1 part; fresh-slaked lime, 4 parts; lard, 120 parts.

2. Ointment of nitrate of mercury, 1 dr.; tar ointment and lard, of each 1/2 oz.

3. (Henke.) Hydrochloric acid, 1 fl. dr.; juniper-tar ointment, 1/2 oz.; marshmallow do., 1 oz.

4. (Pereira.) Tar, 3 dr.; lard, 1-1/2 oz.; melt them together, and stir in of acetic acid (Ph. L.), 2 fl. dr.

5. (Thompson.) Carbonate of soda and sulphuret of potassium, of each 1 dr.; creasote, 1/2 dr.; lard, 1-1/4 oz.

_Obs._ The hair must be cut off close, and the part washed clean before each application. For other forms, see _above_.

=Ointment of Rose.= _Syn._ ROSE POMMADE, ROSE LIP-SALVE; UNGUENTUM ROSÆ, U. ROSATUM, L. _Prep._ 1. (P. Cod.) Washed lard (melted), and roses (centif.), of each 2 lbs.; mix, and in 2 days remelt the mass, and press out the fat; to this last add of fresh roses, 2 lbs., and repeat the process; lastly, colour it with alkanet root if required red.

2. (UNG. AQUÆ ROSÆ——Ph. U. S.) This is spermaceti ointment melted and beaten up with about 2/3rds of its weight of rose water until they congeal. Both the above are simple emollients. The last is an officinal ‘cold cream.’

=Ointment of Rosemary= (Compound). (Ph. G.) _Syn._ UNGUENTUM ROSMARINI COMPOSITUM. _Prep._ Lard, 16 oz.; suet, 8 oz.; yellow wax, 2 oz.; oil of mace, 2 oz.; liquefy in a vapour bath, and when nearly cold, add oil of rosemary and oil of juniper, of each 1 oz., by weight.

=Ointment of Rue= (Span. Hosp.) _Syn._ UNGUENTUM RUTÆ. _Prep._ Fresh rue, 2 oz.; wormwood, 2 oz.; nitre, 2 oz.; lard, 16 oz.; boil till the moisture is expelled.

=Ointment, Rust’s.= _Prep._ Calcined alum, 1-1/2 dr.; camphor, 1/2 dr.; powdered opium, 20 gr. balsam of Peru, 1 dr.; lead ointment, 5 dr.; triturate together. In chilblains, frostbites, frosted limbs, &c.

=Ointment of Sabadil′line.= _Syn._ UNGUENTUM SABADILLINÆ, L. _Prep._ (Dr Turnbull.) Sabadilline, 15 to 20 gr.; lard, 1 oz. Intended as a substitute for ointment of veratrine.

=Ointment of Sav′ine.= _Syn._ UNGUENTUM SABINÆ (B. P., Ph. L. & D.), CERATUM SABINÆ, L. _Prep._ (Ph. L.) White wax, 3 oz.; lard, 1 lb.; melt them together, mix in of fresh savine (bruised), 1/2 lb., and press through a linen cloth.

2. (Ph. D.) Savine tops, dried and in fine powder, 1 dr.; ointment of white wax, 7 dr.; mix by trituration. For the formula of the Ph. E., the uses, &c., see CERATE.

=Ointment of Scrophula′′ria.= _Syn._ UNGUENTUM SCROPHULARIÆ, L. _Prep._ (Ph. D. 1826.) Green leaves of knotted rooted figwort and lard, of each 2 lbs.; prepared suet, 1 lb.; boil till crisp, and strain with pressure. In ringworm, ‘burnt holes’ (_pemphigus gangrenosus_ of children), impetigo, and some other cutaneous diseases; also as an application to piles, painful swellings, &c. In the second it is said to be almost specific.

=Ointment, Simple.= _Syn._ OINTMENT OF WHITE WAX, SIMPLE DRESSING; UNGUENTUM SIMPLEX (B. P., Ph. E.), U. CERÆ ALBÆ (Ph. D.), L. _Prep._ 1. (Ph. E.) Olive oil, 5-1/2 fl. oz.; white wax, 2 oz.; melted together, and stirred whilst cooling.

2. (Ph. D.) Prepared lard, 4 lbs.; white wax, 1 lb.; as the last.

3. (B. P.) White wax, 2; prepared lard, 3; almond oil, 8; melt together, and stir till it becomes solid.

_Obs._ The above are mild emollients, useful in healthy ulcers, excoriations, &c.; but chiefly as forming the basis for other ointments. The corresponding preparation of the Ph. L. is spermaceti ointment. See _below_, also OINTMENT, LARD, &c.

=Ointment, Singleton’s.= See OINTMENTS, EYE.

=Ointment, Smallpox.= _Syn._ UNGUENTUM ECTROTICUM, L. _Prep._ 1. Mercurial ointment, 1-1/2 oz.; beeswax and black pitch, of each 1/2 oz.; expressed oil of mace, 2 dr.; mixed together by a very gentle heat.

2. (Briquet.) Mercurial ointment, 4 parts; powdered starch, 1 part.

3. (Tourriere.) Iodide of potassium (dry and in fine powder), 1 part; expressed oil of mace, 2 parts; black resin, 4 parts; mercurial ointment, 8 parts. Used to prevent the ‘pitting of the pustules.’ See SMALLPOX.

=Ointment, Smellome’s.= See OINTMENTS, EYE.

=Ointment of Soap.= 1. See CERATE.

2. (Camphorated; UNGUENTUM SAPONIS CAMPHORATUM——Hamb. Cod.) White soap (scraped), 1 lb.; water, 1/2 lb.; dissolve by heat; add of olive oil, 5 oz.; and when the mixture has partly cooled, further add of camphor, 1 oz., previously dissolved by heat in olive oil, 1 oz.; lastly, stir until the mass concretes. As an anodyne and stimulating friction in various local affections, as chaps, chilblains, rheumatism, &c.

=Ointment of So′dio-Chlo′′ride of Gold.= _Syn._ UNGUENTUM AURI SODIO-CHLORIDI, L.; POMMADE DE MURIATE D’OR ET DE SOUDE, Fr. _Prep._ (Magendie.) Sodio-chloride of gold, 10 gr.; lard, 4 dr. In scrofulous and syphilitic swellings, indurations, ulcers, &c.

=Ointment of Spermace′ti.= _Syn._ EMOLLIENT DRESSING, SIMPLE OINTMENT, WHITE O.; UNGUENTUM CETACEI (B. P., Ph. L. & D.), U. SPERMATIS CETI, L. _Prep._ 1. (Ph. L.) Spermaceti, 5 oz.; white wax, 14 dr.; olive oil, 1 pint, or q. s.; melt them together by a gentle heat, and stir the mixture until cold.

2. (Ph. D.) White wax, 1/2 lb.; spermaceti, 1 lb.; prepared lard, 3 lbs.; as the last.

3. (B. P.) Spermaceti, 5; white wax, 2; almond oil, 20, or a sufficiency; stir constantly, until it cools.

_Uses, &c._ As an emollient and healing application or dressing to abrasions, excoriations, blistered surfaces, healthy ulcers, chilblains, chaps, &c. In trade, the Dublin formula, with double the amount of lard, is commonly employed. See OINTMENT, LARD, SIMPLE O., &c.

=Ointment of Squills.= _Syn._ UNGUENTUM SCILLÆ, L. _Prep._ 1. (Brera.) Squills (in very fine powder), 1 dr.; mercurial ointment, 2 dr.

2. (Hufeland.) Squills, 1 oz.; liquor of potassia, 2 fl. oz.; reduce to a mucilage by boiling, then add of lard, 2 oz., or q. s. As a resolvent friction to indolent tumours and indurations.

=Ointment of Stavesa′cre.= _Syn._ UNGUENTUM STAPHISAGRIÆ, L. _Prep._ (Swediaur.) Powdered stavesacre, 1 oz.; lard, 3 oz.; melt together, digest 3 or 4 hours, and strain. A very cleanly remedy for itch, and to destroy pediculi on the person. A similar ointment is much used by farriers.

=Ointment of Stramo′′nium.= _Syn._ UNGUENTUM STRAMONII, L. _Prep._ 1. Fresh thorn-apple leaves, 1 part; lard, 4 parts; as ointment of hemlock.

2. (Pereira.) Powdered leaves, 1 oz,; lard, 4 oz.; mix by trituration.

3. (Ph. U. S.) Extract of stramonium, 1 dr.; lard, 1 oz.; as the last.

_Uses, &c._ To dress irritable ulcers, and as an application to painful piles.

=Ointment of Strych′nine.= _Syn._ UNGUENTUM STRYCHNIÆ, L. _Prep._ 1. (Bouchardat.) Strychnine, 16 gr.; lard, 1 oz.; carefully triturated together.

2. (Wendt.) Nitrate of strychnine, 6 dr.; lard, 1 oz.; as last. Both are used as a friction in paralysed parts, &c. From the extremely poisonous character of strychnine it should be used with caution.

=Ointment of Subac′etate of Cop′per.= See OINTMENT OF VERDIGRIS.

=Ointment of Subacetate of Lead (Compound).= _Syn._ UNGUENTUM PLUMBI SUBACETATIS COMPOSITUM (B. P.). _Prep._ Solution of subacetate of lead, 6; camphor 1/8; white wax, 8; almond oil, 20; melt the wax with 16 of the oil on a steam or water bath; remove the vessel, and as soon as the mixture begins to thicken, gradually add the solution of subacetate of lead, and stir the mixture constantly until it cools; then add the camphor, dissolve in the rest of the oil, and mix thoroughly.

=Ointment of Subchloride of Mercury.= See OINTMENT OF CALOMEL.

=Ointment of Subsul′phate of Mercury†.= _Syn._ UNGUENTUM HYDRARGYRI SUBSULPHATUS, L. _Prep._ 1. (Alibert.) Turpeth mineral, 1/2 dr.; lard, 1 oz.

2. (Biett.) Turpeth mineral, 1 dr.; sulphur, 2 dr.; lard, 2 oz.; oil of lemons, 15 drops. In herpes, porrigo, and the scaly diseases.

=Ointment of Sulphate of I′ron.= _Syn._ UNGUENTUM FERRI SULPHATIS, L. _Prep._ (Velpeau.) Sulphate of iron, 1-1/2 dr.; simple ointment, 1 oz. In erysipelas.

=Ointment of Sulphate of Man′′ganese.= _Syn._ UNGUENTUM MANGANESI SULPHATIS, L. _Prep._ From sulphate of manganese, 1 fl. dr.; lard or simple ointment, 1 oz. Alterative and discutient; in similar cases to those in which MECURIAL OINTMENT is employed.

=Ointment of Sulphate of Zinc.= _Syn._ UNGUENTUM ZINCI SULPHATIS, L. _Prep._ (Scarpa.) Sulphate of zinc (in very fine powder), 1 dr.; lard, 1 oz. In some chronic skin diseases attended with a lax state of the tissues, and as a dressing to scrofulous tumours after they have separated and the abscess has been discharged.

=Ointment of Sulphur.= _Syn._ UNGUENTUM SULPHURIS (B. P., Ph. L., E., & D.) _Prep._ 1. (Ph. L.) Sulphur, 1/2 lb.; lard, 1 lb. In the Ph. L. 1836 oil of bergamot, 40 drops, were added. (See 5, Compound.)

2. (Ph. E.) Sulphur, 1 oz.; lard, 4 oz.

3. (Ph. D.) Sulphur, 1 lb.; lard, 4 lbs.

4. (B. P.) Sublimed sulphur, 1; benzoated lard, 4; mix.

_Uses, &c._ In itch, scald-head, &c., in the first of which it is specific. It should be well rubbed in every night until the disease is cured; “but not more than one fourth part of the body should be covered with it at a time.” (A. T. Thomson.)

5. (Compound; ITCH OINTMENT; UNGUENTUM SULPHURIS COMPOSITUM——Ph. L.)——_a._ (Ph. L.) Nitrate of potassa (powdered), 40 gr.; white hellebore (powdered), 10 dr.; sulphur and soft soap, of each 4 oz.; lard, 1 lb.; rub them together.

_b._ (P. Cod.) Alum and sal ammoniac, of each, 1/2 oz.; sulphur, 8 oz.; lard, 16 oz.

_Uses, &c._ In itch, as the simple ointment (1, 2, and 3.) They are more efficacious, but, owing to the presence of white hellebore, the Ph. L. preparation is apt to cause irritation in persons with delicate skins. See OINTMENT, ITCH.

=Ointment of Sulphuret of Mercury.= See OINTMENT OF RED SULPHURET OF MERCURY.

=Ointment of Sulphurated Potash.= _Syn._ UNGUENTUM POTASSÆ SULPHURATE (B. P.) Sulphurated potash, 30 gr.; triturate, and add prepared lard, 1 oz.; mix. See also next preparation.

=Ointment of Sulphuret of Potas′sium.= _Syn._ UNGUENTUM POTASSI SULPHURETI, L. _Prep._ 1. Sulphuret of potassium (dry and in fine powder), 1 dr.; lard, 9 dr. Alibert adds 1 dr. of carbonate of soda.

2. Sulphuret of potassium, 2-1/2 dr.; lard and soft soap, of each 1 oz.; olive oil, 1/2 oz. In several chronic skin diseases, as itch, psoriasis, ringworm, lepra, eczema, &c.

=Ointment of Sulphuret of So′dium.= _Syn._ UNGUENTUM SODII SULPHURETI, L. _Prep._ (Swediaur.) Sulphuret of sodium, 3 dr.; lard, 1-1/2 oz. In itch, for which it is very cleanly and effective. The last two ointments are most powerful when recently prepared.

=Ointment of Sulphuric Ac′id.= _Syn._ UNGUENTUM ACIDI SULPHURICI, L. _Prep._ 1. (Dr Duncan.) Sulphuric acid, 1 dr.; lard, 2 oz.

2. (Ph. D. 1826.) Sulphuric acid, 1 dr.; lard, 1 oz.; mix.

_Uses, &c._ Black, fetid; in itch. It is now seldom used. With oil of turpentine it has been used as a stimulating liniment in rheumatism. An ointment made of 1-1/2 dr. of dilute sulphuric acid to 1 oz. of lard is a good application in prurigo.

=Ointment, Sulta′na.= Spermaceti and white wax, of each 1/4 oz.; oil of almonds and butter of cacao, of each 1/4 lb.; melt together, add of balsam of Peru, 1 dr., stir constantly for a few minutes, and after it has settled pour off the clear portion; to this add of orange-flower water, 2 fl. dr., and stir the mixture constantly until it concretes. A very agreeable species of cold cream.

=Ointment of Tan′nate of Lead.= _Syn._ UNGUENTUM PLUMBI TANNATIS, L. _Prep._ 1. Tannate of lead, 1-1/2 dr.; powdered camphor, 20 gr.; spermaceti ointment, 7 dr. In inflamed piles, &c.

2. (Sundelin.) Decoction of oak bark, 6 fl. oz.; solution of diacetate of lead, 1-1/2 oz.; mix, collect and drain the precipitate, and mix it, whilst still moist, with lard, 1 oz.; camphor, 10 gr. In bedsores.

=Ointment of Tan′nin.= _Syn._ UNGUENTUM TANNINI, U. ACIDI TANNICI, L. _Prep._ (Richard.) Tannin, 2 dr.; water, 2 fl. dr.; triturate them together, then add of lard, 1-1/2 oz. Astringent and hæmostatic. In piles, prolapsus, &c. It is a very cleanly and effective application.

=Ointment of Tar.= _Syn._ UNGUENTUM PICIS LIQUIDÆ (Ph. L. E. & D.), L. _Prep._ 1. (Ph. L.) Tar and suet, of each 1 lb.; melt them together, and press the mixture through a linen cloth.

2. (Ph. E.) Tar, 5 oz.; beeswax, 2 oz.; melt together, and stir the mixture briskly until it concretes.

3. (Ph. D.) Tar, 1/2 pint; yellow wax, 4 oz.; as the last.

_Uses, &c._ As a detergent application in ringworm, scald-head, scabby eruptions, foul ulcers, &c. It should be, in general, at first diluted with half of its weight of lard or oil. See also OINTMENT OF PITCH.

=Ointment of Tartar Emet′ic.= See OINTMENT OF POTASSIO-TARTRATE OF ANTIMONY.

=Ointment of Tin, Chloride= (Nanche). _Syn._ UNGUENTUM STANNI CHLORIDI. _Prep._ Perchloride of tin, 1-1/2 grain; lard, 1 oz. Mix.

=Ointment of Tin, Oxide= (Bate). _Syn._ UNGUENTUM STANNI OXIDI. Oxide of tin rubbed with oil of St John’s wort was formerly applied for the cure of blindness; with Localette’s balsam and honey, for the cure of indolent ulcers.

=Ointment of Tobac′co.= _Syn._ UNGUENTUM TABACI, L. _Prep._ 1. (Chippendale.) Extract of tobacco, 1 dr.; lard, 1 oz. As a friction in neuralgia.

2. (Ph. U. S.) Fresh tobacco leaves, 1 oz.; lard, 12 oz.; as ointment of hemlock. As an anodyne application in irritable ulcers, ringworm, prurigo, and some other skin diseases.

=Ointment, Tripharm′ic.= _Syn._ OINTMENT OF THREE THINGS; UNGUENTUM TRIPHARMACUM, L. _Prep._ From lead plaster, 4 oz.; olive oil, 2 fl. oz.; distilled vinegar, 1 fl. oz.; melt together, and stir until they combine, and a proper consistence is obtained. Cooling and desiccative; formerly greatly esteemed as a dressing.

=Ointment, Trooper’s.= See OINTMENT, MERCURIAL.

=Ointment of Turpentine.= _Syn._ UNGUENTUM TEREBINTHINÆ (B. P.) _Prep._ 1. (Guy’s Hosp.) Camphor, 1 dr.; oil of turpentine, 1 to 2 fl. dr.; dissolve, and add of resin of cerate, 1 oz. As a stimulant and anodyne friction in nephritic and rheumatic pains, engorgements, &c.

2. (Ph. Austr.) Turpentine, 2 lbs.; simple ointment, 1 lb.; mix by a gentle heat. As a stimulant dressing.

3. (B. P.) Oil of turpentine, 16; camphor, 1; soft soap, 2; dissolve the camphor in the turpentine, add the soap, and rub till thoroughly mixed.

=Ointment of Tut′ty.= _Syn._ UNGUENTUM ZINCI OXYDI IMPURI, U. TUTIÆ, L. _Prep._ From prepared tutty, 1 part; simple ointment, 5 parts; mix by trituration. Formerly in great repute in ophthalmic practice, more particularly in inflammation, &c., of the eyelids. See OINTMENT OF OXIDE OF ZINC.

=Ointment of Vera′trine.= _Syn._ UNGUENTUM VERATRIÆ (B. P.); POMMADE DE VERATRINE; Fr. _Prep._ 1. (Magendie.) Veratrine, 4 gr.; lard, 1 oz.; mixed by careful trituration.

2. (Pereira.) Veratrine, 30 gr.; lard, 1 oz.

3. (Turnbull.) Veratrine, 10 to 20 gr.; olive oil, 1 dr.; triturate, and add of spermaceti ointment, 1 oz.

4. Veratria, 8 gr.; prepared lard, 1 oz.; olive oil, 1/2 dr.; rub the veratria and the oil together, then mix thoroughly with the lard.

_Uses, &c._ As a friction in neuralgia, neuralgic rheumatism, gout, dropsy, &c. A piece about the size of a hazel nut is to be rubbed for 10 or 15 minutes over the seat of pain, twice a day. It must not be applied where the skin is unsound, nor to a large surface at a time, and the greatest caution must be used, on account of the extremely poisonous character of veratrine.

=Ointment of Ver′digris.= _Syn._ OINTMENT OF SUBACETATE OF COPPER; UNGUENTUM ÆRUGINIS (Ph. E.), U. CUPRI SUBACETATIS (Ph. D.). L. _Prep._ 1. (Ph. E.) Resinous ointment, 15 oz.; melt by a gentle heat, sprinkle into it of verdigris (in very fine powder), 1 oz., and stir the mixture briskly until it concretes.

2. (Ph. D.) Prepared subacetate of copper, 1/2 dr.; ointment of white wax, 7-1/2 dr.; mix by trituration.

_Uses, &c._ Detergent and escharotic; as an occasional dressing to foul and flabby ulcers, to keep down fungous-flesh, and, diluted with oil or lard, in scrofulous ulceration and inflammation of the eyelids.

=Ointment of Vin′egar.= _Syn._ ACETIC OINTMENT; UNGUENTUM ACETI, U. ACIDI ACETICI, L. _Prep._ 1. (Dr Cheston.) Olive oil, 1 lb.; white wax, 4 oz.; melt them together by a gentle heat, add of strong vinegar, 2 fl. oz., and stir until the mixture concretes. As a cooling astringent dressing, and as an application in chronic ophthalmia.

2. (W. Cooley.) Acetate of morphia, 6 gr.; acetic acid (Ph. L.) and water, of each 1-1/2 fl. dr.; dissolve, add the solution to simple ointment (melted), 1-1/2 oz., and stir the mixture briskly until nearly cold. In chronic ophthalmia, painful inflamed piles, &c.; also to remove freckles, and to allay itching and irritation in several skin diseases.

=Ointment of Walnut Leaves= (_Negrier_). _Syn._ UNGUENTUM JUGLANDIS. _Prep._ Extract of walnut leaves, 3 drams; lard, 4 drams; oil of bergamot, 1 drop. Mix.

=Ointment, White.= Both SPERMACETI OINTMENT and OINTMENT OF CARBONATE OF LEAD were formerly so called, but the name is now obsolete. The CAMPHORATED WHITE OINTMENT of the Ph. L. of 1746 (UNG. ALBUM CAMPHORATUM) was spermaceti ointment to which a little camphor had been added.

=Ointment of White Precipitate.= _Syn._ OINTMENT OF AMMONIATED MERCURY; UNGUENTUM HYDRARGYRI AMMONIATI. (B. P.) Ammoniated mercury, 62 gr.; simple ointment, 1 oz. Mix. See OINTMENT OF AMMONIO-CHLORIDE OF MERCURY.

=Ointment of White Wax.= See OINTMENT, SIMPLE.

=Ointment of Wolfsbane.= See OINTMENT OF ACONITE.

=Ointment of Wood Soot.= _Syn._ UNGUENTUM FULIGINIS. _Prep._ Wood soot and lard, of each equal parts. Mix.

=Ointment of Wood Soot (Compound).= _Syn._ UNGUENTUM FULIGINIS COMPOSITUM. Acetic extract of wood soot, 4 dr.; dried salt, 10 dr.; lard, 14 oz. For ringworm.

=Ointment for Worms.= _Syn._ UNGUENTUM ANTHELMINTICUM, U. VERMIFUGUM, L. _Prep._ 1. (Boerhaave.) Aloes and ox-gall, of each 1 part; marshmallow ointment, 8 parts.

2. (Fr. Hosp.) Aloes and oil of tansy, of each 1 part; dried ox-gall, 2 parts (both in fine powder); lard, 8 parts.

3. (Ph. Bat.) Aloes, 1 dr.; dried ox-gall and petroleum, of each 1-1/2 dr.; lard, 1-1/2 oz.

4. (Soubeiran.) Powdered aloes, 2 dr.; lard, 1 oz.

_Uses, &c._ The above are purgative and vermifuge, applied as frictions to the abdomen. They are chiefly employed for children and delicate females. See OINTMENT, COLOCYNTH.

=Ointment of Yel′low Wax.= _Syn._ UNGUENTUM CERÆ FLAVÆ, L. _Prep._ (Ph. D. 1826.) Beeswax, 1 lb.; lard, 4 lbs.; melt them together. A mild emollient dressing. Some parties regard it as more ‘healing’ than the OINTMENT OF WHITE WAX.

=Ointment of Zinc.= 1. See OINTMENT OF OXIDE OF ZINC.

2. (Compound); UNGUENTUM ZINCI COMPOSITUM, L.——_a._ (Hufeland.) Oxide of zinc and lycopodium, of each 1 dr.; simple ointment, 1 oz. In excoriations and simple ulcerations, especially those of the eyelids, nipples, &c.

_b._ (Thomson.) Oxide of zinc, 1/2 dr.; powdered opium, 5 gr.; lard, 1 oz. As the last, when there is much pain.

=Ointment of Zinc, Cyanide= (Cunier). _Syn._ UNGUENTUM ZINCI CYANIDI. _Prep._ Cyanide of zinc, 12 grains; lard, 5 drams; butter of cacao, 5 drams. Mix.

=OINTMENTS (Flower of).= _Syn._ FLOS UNGUENTORUM, L. _Prep._ From resin, thus, wax, and suet, of each 1/2 lb.; olibanum and Venice turpentine, of each 2-1/2 oz.; myrrh, 1 oz.; wine, 1/2 pint; boil them together, and, lastly, add of camphor, 2 dr. Suppurative; warming.

=O′LEFIANT GAS.= C_{3}H_{4}. _Syn._ ETHYLENE, HEAVY CARBONETTED HYDROGEN, HEAVY CARBURETTED H., ELAYL, ETHENE. A substance discovered by some associated Dutch chemists, in 1795, and composed of carbon and hydrogen in the proportions expressed by C_{2}H_{2} or C_{4}H_{4}.

_Prep._ 1. A mixture of alcohol (rectified spirit), 1 part, and oil of vitriol, 6 parts, is heated in a retort until it blackens, and sulphurous acid begins to be evolved; the product is then passed first through a wash-bottle containing a solution of caustic potassa or milk of lime, and next through a bottle containing concentrated sulphuric acid, the last being furnished with a tube dipping into the water of the pneumatic trough.

2. The vapour of boiling alcohol is passed into a mixture of oil of vitriol diluted with rather less than one half its weight of water, and so heated as to be in a state of tranquil ebullition (320° to 330° Fahr.); the gaseous product is chiefly olefiant gas, and the vapour of water, from which it may be separated as above. No sulphurous acid is formed, nor does the acid blacken as in the last process.

_Prop., &c._ Colourless; neutral; nearly odourless; nearly insoluble in water; alcohol, ether, and the volatile and fixed oils, absorb a portion of it; burns with a brilliant white flame; at a full red heat it suffers decomposition, with deposit of carbon and liberation of light carburetted hydrogen gas; mixed with twice its volume of chlorine and inflamed, hydrochloric acid is formed, and the carbon of the gas is precipitated in the form of dense black soot; if the mixture (best in equal volumes), instead of being kindled, be left standing over water, it soon condenses into a heavy oily liquid (chloride of olefiant gas, Dutch liquid). Sp. gr. ·981; 100 cubic inches weigh 30·57 gr.

=Olefiant Gas, Bromide of.= _Syn._ BROMIDE OF ETHYLENE. From bromine and olefiant gas as Dutch liquid. A colourless liquid, with an ethereal odour, boiling at 265°, and solidifying at 0° Fahr. Sp. gr. 2·16.

=Olefiant Gas, Chlo′′ride of.= _Syn._ DUTCH LIQUID, CHLORIDE OF ETHYLENE. This substance, referred to above, may be easily prepared in any quantity by the following process:——Chlorine and olefiant gas (the latter a little in excess) are conveyed by separate tubes (passing through the same cork) into a glass globe, having a narrow funnel-shaped neck at its lower part, dipping into a small bottle destined to receive the product of their mutual reaction: the newly formed liquid trickles down the sides of the globe into the receiver, and when a sufficient quantity is collected, it is purified by agitating it first with water, and then with sulphuric acid, and, lastly, submitting it to distillation.

_Prop., &c._ Colourless; sweet-tasted; agreeably fragrant, the odour approaching that of oil of caraway; slightly soluble in water; freely so in alcohol and ether; it sinks in water; boils at 180° Fahr.; burns with a smoky greenish flame; is unaffected by oil of vitriol; but decomposed by solution of caustic potassa. It combines with chlorine, forming new compounds. See CHLORIDES OF CARBON (page 403).

=OLEIC ACID.= HC_{18}H_{33}O_{2}. _Syn._ ELAIC ACID. One of the fatty acids discovered by Chevreul, and produced by saponifying oils, and then separating the base from the resulting soap by means of a dilute acid. It now forms an important secondary product in the manufacture of stearic acid. Perfectly pure oleic acid may be obtained as follows:——

1. By saponifying olein, as just noticed.

2. Pure almond or olive-oil soap is decomposed by a dilute acid, and the resulting oily acid is digested in a water bath with half its weight of litharge (in very fine powder) for some hours, constantly stirring; the mixture is then agitated with twice its volume of ether in a close vessel, and in 24 hours the clear ethereal solution is decanted, and decomposed with dilute hydrochloric acid; the oleic acid separates, and the ether mixed with it is expelled by evaporation. To render it colourless, the acid is again saponified with caustic soda, and the soap thus retained is repeatedly dissolved in a solution of soda, and as often separated by adding common salt; this soap is, lastly, decomposed by dilute hydrochloric acid, as before.

3. (H. N. Fraser, pharmacist.) Oil of cotton seeds (‘winter oil’), deprived of most of its stearin by chilling and pressure, is first saponified with potassa, using a slight excess of the base. The soap is then treated with tartaric acid, or any other acid which will make a soluble salt with potassa, until the base is completely neutralised; the residue is washed until a mass is left about the consistence and colour of cerate, free from any of the salt; this is heated for several hours with nearly its weight of litharge, and three or four times its bulk of water; the resulting compound is shaken up while yet warm with ether, and allowed to stand until all the soluble matter separates.

This separates the stearate, and leaves a nearly pure oleate of lead. The clear liquor is decanted and briskly shaken with dilute muriatic acid for a few minutes to precipitate all the chloride of lead, the lighter liquid washed to remove traces of muriatic acid and filtered; the filtrate heated slowly in a water bath, and the ether distilled until the residue ceases to have an ethereal odour. The product is about 60 per cent. of the bulk of the oil.

Crude oleic acid may be purified as follows:——Expose it repeatedly to a temperature of about 45° F., and express the liquid portion. With this mix an equal bulk of solution of sulphurous acid, place the mixture in the light, and shake it frequently until no more colour is discharged. After separation the oleic acid is to be washed repeatedly with cold distilled water, and put into bottles, which should be kept filled up and in a cool place.

_Prop., &c._ A colourless oily acid, insoluble in water, soluble in alcohol, ether, and oil; with the bases it forms salts called oleates. The best kind of oleic acid is known as “pale cloth oil.”

O’LEIN. C_{57}H_{104}O_{6}. _Syn._ ELAIN; HUILE ABSOLUE, Fr. The liquid portion of the fixed oils and fats. By saponification it yields oleic acid.

_Prep._ 1. Olive oil or almond oil is digested for 24 hours with a quantity of caustic soda lye, only sufficient to saponify one half of the oil, and the undecomposed oily portion (olein) is then separated from the alkaline solution and newly formed stearine soap.

2. The saponified mixture of oil and alkali (see No. 1) is digested with proof spirit until all the soap is dissolved out, and the olein separates and floats on the surface; the latter, after repose, is decanted.

3. Almond or olive oil is agitated in a stout bottle with 7 or 8 times its weight of strong alcohol (sp. gr. ·798), at nearly the boiling point, until the whole is dissolved; the solution is next allowed to cool, after which the clear upper stratum is decanted from the stearin which has been deposited, and, after filtration, the spirit is removed by distillation at a gentle heat; by exposure at a very low temperature it deposits any remaining stearin, and then becomes pure.

_Prop., &c._ The products of the last two formulæ have only a very slight yellow colour, but may be rendered quite limpid and colourless by digestion for 24 hours with a little pure, freshly burnt animal charcoal, and subsequent filtration. In this state the olein is perfectly neutral to test paper, does not in the slightest degree affect metallic bodies immersed in it, and does not thicken by exposure to the greatest cold. Olein is used by watchmakers for their fine work. Some years ago the product of the last formula was sold, by a certain metropolitan house, as ‘watchmakers’ oil,’ at 1s. 6d. a drachm. Commercial olein is generally lard oil. The refined oleic acid of the stearin works also commonly passes under the name. Olein burns well in lamps; but oleic acid does not do so unless when well refined, and when the wick-tube is so formed as to remain cool. See LARD OIL and OLEIC ACID.

OLEOM’ETER. _Syn._ ELAÏOMETER, ELÆOMETER, OIL-BALANCE. A delicate areometer or hydrometer, so weighted and graduated as to adapt itself to the densities of the leading fixed oils. As the differences of the specific gravities of these substances are inconsiderable, to render it more susceptible the bulb of the instrument is proportionately large, and the tube or stem very narrow. The scale of the oleometer in general use (Gobby’s) is divided into 50 degrees, and it floats at 0 or zero in pure poppy oil, at 38 or 38-1/2 in pure almond oil, and at 50 in pure olive oil. The standard temperature of the instruments made in this country is now 60°; those made on the Continent, 54·5° Fahr. The oil must therefore be brought to this normal temperature before testing it, by plunging the glass cylinder containing it into either hot or cold water, as the case may be; or a correction of the observed density must be made. The last is done by deducting 2 from the indication of the instrument for each degree of the thermometer above the normal temperature of the instrument, and adding 2 for every degree below it. Thus: suppose the temperature of the oil at the time of the experiment is 60° Fahr., and the oleometer indicates 61°; then——

60·0° Actual temperature. 54·5° Normal temperature. ———— 5·5° Difference.

Indication of the oleometer 61·0 The difference 5·5 × 2 = 11·0 ———— Real density 50·0

Suppose the temperature observed at the time of the experiment is 52°, and the oleometer indicates 45°; then——

54·5 Normal temperature. 52·0 Actual temperature. ———— 2·5 Difference. ————

Indication of the oleometer 45·0 The difference 2·5 × 2 = 5·0 ———— Real density 50·0 ————

The oil is, therefore, presumed to be pure. See HYDROMETER, OILS (Fixed), and SPECIFIC GRAVITY.

=O′LEO-PHOSPHOR′IC ACID.= An acid compound found by Fremy in the brain and nervous matter.

=OLEO-RES′INS.= The natural compounds of resin and essential oil forming the vegetable balsams and turpentines. Copaiba, Canada balsam, and Venice turpentine are examples. Certain extracts prepared with ether, as the fluid extracts of cubebs and pepper in the Ph. U. S., may be regarded as oleo-resins. See EXTRACT.

=OLEO-SAC′CHARUM.= _Syn._ ELÆOSACCHARUM. Sugar aromatised or medicated by being rubbed up with an essential oil. The oleosacchara of aniseed, caraway, cinnamon, peppermint, pennyroyal, and the other like essential oils, are made by rubbing 15 to 20 drops of the respective oils with white sugar, 1 oz.——The Ph. Græca 1837 prescribes 1 part of oil to 20 parts of sugar.——The Ph. Austr. 1836 and Ph. Bor. order the same proportions, or 3 drops of oil to the dr., and 24 drops to the oz., of powdered sugar. When intended for making extemporaneous distilled waters, 1 dr. of magnesia is a common addition. The oleosacchara of citrons, lemons, oranges, &c., are made from the peels, as follows:——After cleaning off any specks in the outer rind of the fruit, rub a large piece of loaf sugar on it until the yellow rind is completely removed. Those parts of the sugar which are impregnated with the essence are, from time to time, to be cut away with a knife, and put into an earthen pot. The whole being thus taken off, the sugared essence (oleosaccharum) is to be closely pressed down in the pot, tied over with bladder, and preserved in a cool place for use.

=OLIB′ANUM.= _Syn._ OLIBAN, INDIAN OLIBANUM, FRANKINCENSE. A gum resin obtained from _Boswellia thurifera_ or _serrata_. It is stimulant, astringent, and diaphoretic. It is burnt as incense in the temples of India and in Roman Catholic churches. African or Arabian olibanum is produced by _Boswellia floribunda_. (Royle.) This substance must not be confounded with the resin noticed at page 761.

=Olibanum.= This gum resin is yielded by two varieties of the plant known as _Boswellia_——one the _B. floribunda_, being a native of Africa, the other, the _B. serrata_, growing in Asia. Olibanum occurs in the form of fragments, which are sometimes pale yellow, and at others of a reddish colour; these fragments have a splintery fracture, a mealy surface, a faintly balsamic odour and a bitter taste. “It consists of about 4 or 5 per cent. of a volatile oil, 56 per cent. of a resinous acid, 30 to 36 per cent. of gum, and 6 per cent. of bassorin.”[67] Incense, of which olibanum forms one of the ingredients, owes much of its pleasant balsamic odour when burning to its presence. It is also used in pharmacy.

[Footnote 67: Payen.]

=OL′IVE.= _Syn._ OLEA, OLIVA, L. The _Olea Europæa_ (Linn.), a native of the South of Europe. The unripe fruit is preserved in brine (SPANISH OLIVES, FRENCH OLIVES); the ripe fruit furnishes olive oil; the bark is bitter, astringent, and febrifuge, and has been used as a substitute for cinchona bark; it yields a gum-like substance (OLIVE GUM), which was formerly reported vulnerary, and contains olivine. The olive tree has in all ages been held in peculiar estimation as the bounteous gift of Heaven to man. Some authors have styled it “a mine on earth.” It is remarkable for yielding a fixed oil from the pericarp instead of from the seed.

=OLLIVIER’S BISCUITS.= See PATENT MEDICINES.

=OLIVINE.= _Syn._ CHRYSOLITE. A crystallised double silicate of magnesia and iron, found in basaltic and volcanic rocks, and very frequently in masses of meteoric iron. It is sometimes yellow in colour, but mostly green.

=Olivine.= (Dr Landerer.) _Syn._ OLIVINA. _Prep._ Treat olive leaves with acidulated water, concentrate, precipitate with ammonia, re-dissolve the washed precipitate in a diluted acid, purify with animal charcoal, filter, and reprecipitate with ammonia.

=OM′ELET.= _Syn._ OMELETTE, Fr. A variety of pancake or fritter made of eggs and other ingredients. Omelets may contain bacon, ham, herbs, fish, shell-fish, cold meat, cold game, fruit, or anything else at hand at the pleasure of the cook. ‘Spirit omelets’ are made by pouring a little brandy, rum, or whisky over them on serving them up, and setting it on fire for a moment just before placing the dish on the table. “Where is the man or woman cook but says they know how to make an omelette, and that to perfection? But this is rarely the case. It is related of Sarah, the Duchess of Marlborough, that no one could cook a ‘fraise,’ as it was then called, for the great duke but herself. The great point is, if in an iron pan, it should be very clean and free from damp which sometimes comes out of the iron when placed on the fire. The best plan is to put it on the fire, with a little fat, and let it get quite hot, or until the fat burns; remove it, and wipe it clean with a dry cloth, and then you will be able to make the omelette to perfection.” (Soyer.)

The following formula for a plain omelet is by the above culinary authority:——“Break four eggs into a basin, add 1/2 teaspoonful of salt, and 1/4 do. of pepper, and beat them up well with a fork; put into the frying-pan 1-1/2 oz. of butter, lard, or oil, place it on the fire, and, when hot, pour in the eggs, and keep on mixing them quickly with a spoon until they are delicately set; then let them slip to the edge of the pan, laying hold by the handle, and raising it slantways, which will give an elongated form to the omelette; turn in the edges, let it rest a moment to set, turn it over on to a dish, and serve.” “It ought to be of a rich-yellow colour, done to a nicety, and as light and delicate as possible.” “2 table-spoonfuls of milk and 1 oz. of the crum of bread, cut into thin slices, may be added.”

MIXED and FANCY OMELETS are made by simply dropping the ingredients, cut into dice or fragments, into the above. ANCHOVY, OYSTER, and SHRIMP OMELETS are generally prepared by placing a few spoonfuls of the respective sauces in the centre of each when nearly dressed,

=ONGUENT (de la Mère).= A stimulant and digestive ointment, very popular in French pharmacy.

_Prep._ (P. Cod.) Black pitch, 1 part; butter, lard, litharge, suet and yellow wax, 4 parts; olive oil, 8 parts.

=ON′ION.= _Syn._ CEPA, L. The bulb of _Allium cepa_. The onion is diuretic, expectorant, rubefacient, and stimulant. The juice, made into a syrup with sugar (SYRUPUS CEPÆ), has been given in chronic catarrh, diarrhœa, croup, dropsy, and calculus. Roasted and split open, onions have been applied as poultices to suppurating tumours, and applied to the pubes to relieve suppression of urine in children. According to Dr Cullen, “onions are acrid and stimulating, and possess little nutrient power. In bilious constitutions they generally produce flatulence, thirst, headache, and febrile symptoms; but where the temperament is phlegmatic they are of infinite service, by stimulating the system, and promoting the excretions, particularly expectoration and urine.” They also possess antiscorbutic and soporific properties.

=Onions, To Chop.= “Few persons know how to chop onions properly. In the first place all the dry skin must be removed, then a thin slice off the top and bottom, or they will be bitter, then cut them into thin slices, dividing the onion, and cut crossways to form dice. If a very slight flavour is required and the onion is strong, like in the North of England, for it must be remembered that the further north you go the stronger the flavour of the root, and if French receipt books are exactly copied, it is no wonder complaints are made of the preponderance of the flavour of the onion; in which case, when chopped, put them in the corner of a napkin or cloth, wash them in water, squeeze them dry, then put them back on the board, and chop finer, or sometimes only rubbing the pan or the meat with the onion is quite sufficient.” (Soyer.)

=O′NYX.= A sub-species of quartz often wrought into small ornamental articles. Among jewellers, any stone exhibiting layers of two or more colours, strongly contrasted, is called an ‘onyx.’ A regularly and richly banded agate of this class is much prized for cameos. The _Sardonyx_ of the ancients is a variety of onyx. It is so called from _Sard_ or _Sarda_, a rich dark-red variety of carnelian, stripes of which in the stone alternate with white stripes. See GEMS.

=O′PAL.= A mineral allied to agate and chalcedony, but distinguished by its peculiar resinous lustre. The variety most admired as a gem is the precious or noble opal, which is remarkable for its beautiful play of colours. The finest opals come from Hungary, and although usually very small, will, if of good quality, realise as much as £5 each. Their value increases in a much greater ratio than their increase in size. They are also found in Saxony and in North America. The largest known specimen of an opal is that in the Imperial Cabinet at Vienna, the dimensions of which are five inches by two and a half. _Girasol_, _Cacholong_, _Hyalite_, and _Menilite_ are varieties of opal. See GEMS and PASTES.

=O′OLITE.= A variety of limestone composed of a number of collections of small round particles, bound together by a calcareous cement. The resemblance the mass is supposed to bear to the roe of a fish has caused oolite to be called _roestone_. When the grains are of larger dimensions it is called _peastone_. The little spherical bodies of which the stone is composed are mostly formed of concentric layers of carbonate of lime arranged round a grain of sand, a fragment of shell or some other nucleus.

The building stones of Caen, Portland, and Bath are all oolitic limestones. When first quarried they are mostly soft, a circumstance which admits of their being easily sawn and carved. They harden by exposure to the air.

In _geology_ the term “oolite” has a wider signification, and is applied to an important division of the middle secondary rocks of England, underlying the chalk formation and rich in the interesting fossil remains.

=OPHTHAL′MIA.= _Syn._ OPHTHALMITIS, L. Inflammation of the eye. In ordinary cases this disease is confined to the external membrane of the globe of the eye or to the eyelids; but it occasionally attacks the sclerotica, cornea, choroid coat, and retina.

The common causes of ordinary or conjunctival ophthalmia are the sudden exposure of the organ to a cold easterly wind, to dust, gritty particles, or to any external irritation or injury.

The symptoms are, in part, those common to local inflammation. The eye or eyelids become more or less bloodshot, swollen, and tender, and a sensation resembling that induced by the presence of particles of sand or some gritty substance, accompanied by much heat and a pricking pain, is almost constantly experienced. The secretion becomes yellowish and glutinous, and during the night frequently glues, as it were, the lids together. Sometimes only one eye is attacked, but after two or three days the disease extends to the other.

The treatment of mild cases of conjunctival ophthalmia is extremely simple. In general, it may be relieved by fomentations of warm water or decoction of poppy-heads and the use of aperient medicines, to which leeches and cupping may often be added with advantage.

“To apply a lotion to the eyes,” writes Dr Gardner, “the best way is to use a large camel’s-hair pencil or brush. Fill it with the lotion, draw down the lower lid, and apply the brush; the fluid will now come out of it into the eye.

“In order to get it well within the upper lid, move the latter up and down, and the whole surface will be wetted. This is important, because the usual way of applying lotions to the inside of the eye is very inefficient, if not entirely useless. The brush should be washed in warm water after using it.”[68]

[Footnote 68: ‘Household Medicine.’ Smith, Elder, & Co.]

In cases where the inflammation is very severe, the pain very acute, or the vision in the slightest degree impaired, as well as in those accompanied by a discharge of matter or pus, no time should be lost in seeking the services of the oculist.

_Animals._——All animals are liable to attacks of catarrhal or common ophthalmia, which may originate from various causes, such as exposure to cold, influenza, or the presence of foreign substances, such as bits of chaff, the husks of oat, small seeds, &c.

In horses, in addition to the above, it may be caused by a blow from the whip. In animals affected by it the eye becomes watery and half closed, the membrane looks thickened, and the eye is frequently bloodshot. If due to the presence of any foreign body this must be removed, either by means of the fingers, a handkerchief, or a camel’s-hair brush, or, if necessary, by the forceps.

The treatment consists in bathing the eyes with tepid milk and water, after which an alum or zinc lotion may be applied. A mild physic ball should also be administered.

=Ophthalmia, Purulent.= This dreadful disease, which, like the above, is a form of inflammation of the mucous membrane of the eye, differs from ordinary ophthalmia in being accompanied with a discharge of pus, too frequently terminating in total and irrecoverable blindness of one or both eyes, and in being very contagious.

Purulent ophthalmia is very prevalent in India, Persia, and Egypt, and from the circumstance that large numbers of our troops were affected with it on their return from the campaign in Egypt, in the beginning of the present century, before which time it was unknown in England, it acquired the name of “Egyptian ophthalmia.”

Although of late years its ravages amongst the soldiers of our own as well as of other European nations have considerably abated, the disease is still more or less prevalent in the British, French, Prussian, Austrian, Bavarian, Italian, Spanish, Belgian, Swedish, and Russian armies. Purulent ophthalmia is also by no means uncommon amongst the non-military population, such as the poorer classes and their children, and the children in workhouses, asylums, and pauper schools. Dr Parkes says it has evidently been propagated amongst the civil inhabitants by the soldiery.

The following narrative of an outbreak of purulent ophthalmia that occurred on board a vessel freighted with slaves for the West Indies forcibly illustrates the character and infectious nature of this disease.

In the year 1819 the “Le Roideur,” a French vessel, sailed with a cargo of 160 negroes from Bonny, on the coast of Africa, to Guadaloupe. The “Le Roideur’s” crew consisted of 22 men, so that the number of human beings on board, including officers, was 182. No epidemic had been observed amongst the natives from whom the slaves had been taken, and further, at the time of sailing the crew were in perfect health, and the slaves were said to be free from disease of any kind.

The wretched Africans were closely packed in the hold of the vessel, the air of which, as may be imagined, soon became frightfully foul; and after about the thirtieth or fortieth day, the drinking water running scarce, their daily allowance was reduced from 8 oz. to half a wineglassful. Then it was that ophthalmia first showed itself amongst the wretched occupants of the hold, the lids of their eyes becoming red and inflamed. The surgeon of the vessel advised that they should breathe in succession the purer air of the deck. But this course had to be relinquished, since it was found that many of the negroes on leaving the hold jumped over the side of the vessel, and purposely drowned themselves. The disease, which was of a most virulent kind, spread rapidly amongst the negroes, and from these to the crew.

A notable fact demonstrating the propagation of purulent ophthalmia by material particles was the circumstance that the first amongst the crew who was seized was a sailor who guarded the hatch communicating with the hold. The day after another of the crew was attacked, and in three days after this the disease had assailed the captain, and almost the whole of the crew. The disease continued to spread daily, until at last there remained one only of the whole crew unaffected and with sight intact, and to him was deputed the important task of steering the vessel. Great fear was manifested lest he too might eventually be overtaken with the total or partial blindness that had come to the remainder of the crew.

The “Le Roideur” reached Guadaloupe on the 21st of June, when it was found that thirty more of the negroes had entirely lost their sight (thirty-six of whom had been thrown into the sea, since they were unsaleable), twelve had lost the sight of an eye, and fourteen were more or less blind.

Of the crew, twelve including the surgeon were entirely blind, five were blind of one eye, and four partially so.

Three days after the arrival of the vessel in port the steerer of the vessel was seized with the disease.[69]

[Footnote 69: Blythe.]

About thirty years ago a curious discovery in connection with purulent ophthalmia was made by Dr Loffler, a Prussian army surgeon. Many of the soldiers of his regiment being disabled by this disease, he submitted the eyes of all the men to a rigorous daily inspection, and he discovered in the lining membrane of the eyelids of some of them certain small granular bodies resembling boiled sago grains. Furthermore he noticed that, although those soldiers whose eyelids presented this peculiarity showed then no indications of the disease, they were subsequently invariably attacked by it; whilst those from whose eyelids the sago grains were absent as invariably escaped.

Subsequent investigators, amongst whom may be mentioned Drs Welch and Marston, have confirmed the accuracy of Dr Loffler’s observations and the soundness of his conclusions——that the occurrence of the sago grains is always an antecedent condition to an attack of purulent ophthalmia.

As to the nature of the little granular bodies known to pathologists as ‘sago grains,’ it seems to be generally admitted that they are follicles situated directly beneath the epithelium, which, in a healthy condition of the lining membrane, are not apparent, but which become swollen and enlarged when the membrane itself is in an unhealthy and irritable condition. In this respect they resemble the enlarged glands met with in scrofulous and weakly children.

“In a regiment the proneness to the development of sago grains is found to decrease as life advances; that is, to be much greater in young soldiers than in old ones, and by a parity of reasoning it is assumed to be greater in a community of children than in a community of adults. In any individual, and therefore in any community, the sago grains may disappear without producing mischief; but, as a matter of fact, sources of irritation to the eyes abound in the world, and when these sources of irritation act upon eyelids in which sago grains are already present, they often excite the contagious form of ophthalmia.”[70]

[Footnote 70: Brudenell Carter.]

The diffusion into the atmosphere of the purulent discharge accompanying this form of ophthalmia is undoubtedly the means by which the disease is spread.

Hence it is that if one eye be affected the other may be saved from an attack by being hermetically sealed up——a method of prevention sometimes adopted by the ophthalmic surgeon.

Mr Brudenell Carter says “that the secretion passes along the tear-passages into the nostrils, and is driven out with the expired air at every breath; besides the chances of direct contact that must exist when a child with ophthalmia is perpetually sending into the atmosphere what I may describe as a spray of contagious particles.”

Medical opinion is in some measure divided as to the origin of this disease; for whilst there are authorities who believe that its propagation is due to contagion assisted by insanitary environments, there are others who incline to the supposition that these latter conditions alone are sufficient to produce it. Whether this is so or not there can be no question that impure air, overcrowding, filth, and deficient water supply, which implies insufficient ablution, serve to intensify and perpetuate it.

So strongly and confidently impressed are Messrs Welch and Marston of the connection between unhealthy surroundings and prevalent ophthalmia, that they regard the two as cause and effect, and state their belief “that the presence or absence of ‘sago grains’ affords a delicate test of the sanitary state of a school, a regiment, or any similar community.”

Ample and painful confirmation of these views is afforded by the prevalence of the disease amongst the children, more particularly those who live in very poor and crowded districts. The pitiable, blear-eyed little creatures that one meets with in these localities are very frequently the victims of purulent ophthalmia, and as such bear unfailing testimony to the insalubrity and squalor of the homes in which they dwell.

Stromeyer states that he has met with the ‘sago grains’ in the eyelids of many domestic animals, more particularly pigs, the granules being always in proportion to the more or less dirty condition in which the animals were kept.

The above statements plainly indicate the means by which the disease is to be combated. Of these, thorough ventilation and pure air are the most important. Stromeyer records how, by simply ventilating some barracks, he reduced to an amazing extent a number of cases of the disease, which had broken out in the Hanoverian army. Possibly this result was due to the removal, by the current of air from the apartment of the dried particles of contagious matter.

Ablution, which, carefully performed, is, in addition to ventilation, an important curative agent, may, through the neglect of certain precautions, assist to spread the disease.

This it will assuredly do if the basins employed by the patients for washing their eyes are not thoroughly cleansed and disinfected after being used. Furthermore, the towels may be made to spread the infection, unless they too are thrown into some disinfecting solution after use, and unless a separate towel is appropriated to each patient. The danger of reinoculation may ensue if each towel is not changed sufficiently often. The bed-clothes of the affected persons, as well as the pillowcases, should be frequently renewed, the latter every day, since they collect and disseminate the discharges falling on them from the patient.

Medical authorities also strongly recommend the isolation of the patient, and then consequent separation from healthy persons as soon as ever the disease shows itself in a regiment, a school, or amongst any body of persons congregated together; a daily inspection of the eyes of each is recommended, so that whenever the “sago grains” develop themselves, the individuals so attacked may be removed, and placed under proper treatment.

The after effects of the various forms of contagious ophthalmia are thickening and distortion of the eyelids, more or less serious defect of vision, and not unfrequently total blindness.

During the course of the disease relapses from the most trifling causes frequently occur, and Warmolow states that a person who has once been affected with it is not safe against a recurrence, and should be assiduously watched.

=Ophthalmia, Infantile, Purulent.= This disease very frequently attacks infants of 3 or 4 days old. It is distinguished by redness of the edges of the eyes, the lids of which are often glued together. Upon looking into the eye the lining membrane is seen to be swollen and red. Infantile purulent ophthalmia, although yielding much more readily to proper treatment than that which attacks adults, makes rapid progress if neglected, and may jeopardise the sight of the babe; hence the great importance of calling in efficient medical aid as soon as ever it makes its appearance.

=Ophthalmia, Strumous, or Scrofulous.= This form of ophthalmia is generally met with in children of scrofulous habit of from 4 to 10 or 11 years of age. Its most distinctive characteristic is the inability of the sufferer to bear the light, the effect of which is that the eyes are kept spasmodically partially closed. If the eyes are examined, a slight fulness of the vessels usually stopping at the edge of the cornea is observable, and about the line dividing the cornea and sclerotic coat small opaque pimples or pustules are visible. This variety of ophthalmia, being the outcome of a constitutional taint, is frequently very obstinate, and yields with difficulty to medical treatment, besides being very liable to reappear. It is not unfrequently accompanied with a troublesome cutaneous affection known as _Crusta lactea_, which occurs on the cheeks, and arises from the irritation caused by the flow down the cheeks of the acrid lachrymal secretion. The usual treatment consists in improving the general health and strength of the patient by means of tonics, such as quinine, quinine and iron, cod-liver oil, or syrup of iodide of iron. The diet should be nutritious and easy of digestion, and there should be no stint of fresh air.

=O′′PIATES.= _Syn._ OPIATA, L. Preparations containing opium. The word is often applied in a general sense to anodynes and soporifics. In French pharmacy the name is commonly used synonymously with confections, as in the following preparations:——

ANTI-DYSENTERIC OPIATE——Quarin. Purified opium, 4 gr.; ipecacuanha, 1/2 dr.; tormentilla, 1 dr.; syrup of whortleberries and conserve of red roses, of each 6 dr.——_Dose._ A teaspoonful every hour.

ANTI-HYSTERICAL OPIATE——Trousseau and Reveil. Powdered indigo, 1 oz.; white honey, 3 oz.——_Dose_, 1 tablespoonful daily, gradually increased until the whole is taken in a day. In hysteria, epilepsy, and nervous affections of an epileptic character.

BALSAMIC OPIATE——Trousseau and Reveil. Oleo-resin (balsam) of copaiba, 1 oz.; cubebs (in powder), 3 oz.; potassio-tartrate of iron, 2-1/2 dr.; syrup of quince, q. s. In gleet.——_Dose_, 3 boluses the size of a nut, thrice daily.

CHARCOAL OPIATE——Ratier. Willow charcoal (recent), 1 oz.; prepared chalk, 1 dr.; powdered white sugar, 2 oz.: rose water, q. s. to form an electuary. In diarrhœa and incipient cholera, in dysentery with fetid stools, and in gastralgia, flatulence, &c. By substituting calcined magnesia for chalk it becomes an excellent remedy for habitual constipation.

CUBEB OPIATE——Deyeaux. Powdered cubebs, 4 dr.; powdered camphor, 1 dr.; mix, and divide it into 18 powders.——_Dose._ One, 3 or 4 times daily, in gleet, painful and scalding micturition. &c.

=O′′PIUM.= _Syn._ OPIUM (B. P., Ph. L., E, & D.), L. The juice inspissated by spontaneous evaporation, obtained by incision from the unripe capsules of the _Papaver somniferum_, grown in Asia Minor.

_Hist._——“It is uncertain at what period opium was first known and introduced into medicine. Hippocrates recommends the _meconion_ or _poppy juice_, in a disease of the uterus; and Dioscorides, on the authority of Erasistratus, tells us that Diagoras (who was contemporary, it is supposed, with Hippocrates) condemned the use of opium. These are, I believe, the most ancient Greek authorities who speak of this substance; and it is impossible, I think, to arrive at any accurate conclusion from their remarks whether opium had, or had not, been known long before their time, though Alston infers, from the little use made of it by Hippocrates, as well as from Diagoras condemning its use in diseases of the eyes, that its virtues were not known long before him. Dioscorides and Pliny mention that the expressed juice of the heads and leaves is termed _meconium_, and that it is much weaker than opium. Theodore Zwinger, Sprengel, and others have supposed that the _nepenthes_ of Homer was opium. It would appear that opium was not much employed until the time of the Arabs, except in the form of the confections known as Theriaca, Mithridatica, &c. The word opium is derived from _otos, the juice_.”[71]

[Footnote 71: Pereira.]

_Var._——1. EGYPTIAN; in roundish flattened lumps; inferior to Turkish opium.——2. ENGLISH; often equal to the best Smyrna.——3. FRENCH; resembles the last.——4. GERMAN; similar to English opium,——5. INDIAN;——_a._ BENARES; in large balls;——_b._ MALWA; in roundish flattened cakes, of 9 or 10 oz. in weight each;——_c._ PATNA, in balls or square cakes; inferior to Turkey opium.——6. LEVANT; same as Smyrna opium.——7. PERSIAN; in rolls or sticks, 6 × 1/2 inch; inferior; resembles hepatic aloes in appearance.——8. SMYRNA; in irregular, rounded, flattened pieces, varying in weight from 2 or 3 lbs. to only as many oz. It forms the best variety of Turkey opium, and is particularly rich in morphia. It is the only one adapted for the manufacture of the salts of morphia, as it contains on the average from 7 to 9% of that alkaloid, and usually yields about 12 to 12·5% of hydrochlorate of morphia, which is more than can be obtained from any other variety of opium.[72]——9. TURKEY; of which two varieties are known in commerce, viz. Constantinople opium and Levant or Smyrna opium, noticed above. Constantinople opium is generally in small, flattened, roundish cakes, 2 to 2-1/2 inches in diameter, and covered with poppy leaves. It is more mucilaginous and less esteemed than Smyrna opium, from which it may be distinguished by the last being always covered with the reddish capsules of a species of Rumex.

[Footnote 72: Of five kinds of Smyrna opium examined by Merk, the worst were found to yield 3 to 4 per cent. of morphia, and the best from 13 to 13·5 per cent.]

The following account of the method of opium collection, adopted in Asia Minor, is extracted from a paper in the ‘Pharmaceutical Journal,’ contributed by Messrs Maltass and Wilkin.[73] About the end of May the plants arrive at maturity, and the flowers expand. A few days after the petals have fallen the capsule is ready for incision.

[Footnote 73: First series, 14th volume.]

This operation is performed in the afternoon of the day and in the following manner:——A transverse incision is made with a knife in the lower part of the capsule, the incision being carried round until it arrives nearly at the part where it commenced; sometimes it is continued spirally to half way down its starting point. The greatest nicety is required to avoid cutting too deep, and penetrating the interior coating of the capsule, as this would cause the exuding milky juice to flow into the inside.

The following morning those engaged in collecting the opium lay a large poppy leaf on the palm of the left hand, and having a knife in the right hand, they scrape the opium which has exuded from the incision in each capsule, and then transfer it from the knife to the leaf, until a mass of sufficient size has been formed, when a second poppy leaf is placed over the top of the mass. If the dew has been heavy during the night the yield is greater, but the opium is dark in colour; if, on the contrary, there has been no dew, the yield is less, but the opium is of a lighter colour. A high wind is prejudicial, as the dust raised from the pulverised soil adheres to the exudation, and cannot be separated. The poppy capsules are cut but once, but as each plant will from one stem produce several branches, and each branch produce a flower, it is usual to pass over the field a second or a third time, to cut such capsules as were not ready at the first cutting. After the opium is collected it is dried in the shade.

The proceeds arising from the sale of the opium crop in British India form a considerable item in the revenues of our Eastern Empire; hence the poppy as the source of this valuable export, almost the whole of which goes to China, is very extensively cultivated in India.

In the year ending March 31st, 1872, 93,364 chests, valued at £13,365,228, were exported from British India. Of this quantity 49,455 chests were from Bengal, and Bombay 43,909. They were distributed thus:——

To China 85,470 chests. ” the Straits Settlements 7,845 ” ” Ceylon, Java, Mauritius, and Bourbon 38 ” ” the United Kingdom 4 ” ” other countries 7 ” —————— 93,364 ——————

The net revenue to the Indian Government from this source in the year 1871-72 was £7,657,213.[74]

[Footnote 74: Flückiger and Hanbury.]

A large track of country in Bengal, some 600 miles in length and 200 in breadth, watered by the Ganges, embraces the chief opium district of India. A comparatively small quantity of opium is obtained from the mountain parts of the North of India. This latter is yielded by the _Papaver somniferum_, whilst that from the plains is the produce of the _Papaver officinale_.

In India the plant is reared in a rich and well-manured soil, and thrives best in mild moist localities. It requires careful weeding and thinning whilst growing, and when necessary the ground is irrigated. As in Asia Minor, when the time comes for making incisions in the capsules for the purpose of collecting the exuding juice, this latter is always found to be less in quantity if it be rainy weather. In India the poppy begins to flower at the end of January, or the commencement of February and about three or four weeks after its effervescence the capsule, which is about as large as a hen’s egg, is in a condition to be tapped. This operation is always performed at early morn, before sunrise, by means of a little iron instrument notched at the smaller end like a saw.

The treatment to which the milky exudation, which subsequently hardens into opium, is subjected differs only in details from that followed in Asia Minor, and in being more carefully and elaborately carried out. For instance, it is first allowed to stand for some time in a shallow brass dish tilted on one side, by which means there drains away a thin watery fluid, the presence of which seriously impairs the quality of the opium. After this it is dried equably by three or four weeks’ exposure to the air, and in this condition is packed in earthen jars and taken by the native cultivators to the factory. Here, after being tested and weighed, it is thrown into immense vats, which contain the accumulated produce of whole districts; and when the several samples have been kneaded together it is removed, and formed into balls or cakes. The soft opium is made into balls by being pressed into brass cup-shaped moulds, lined throughout with petals of the poppy, which are made to adhere to each other as well as to the ball of opium by means of an adhesive fluid obtained from an inferior kind of opium; other petals are then by the same means stuck on to the upper part of the ball so that the whole of this is covered with a thin layer of them. The balls are next removed to the drying-room of the factory, where they are arranged in tiers on lattice-work shelves. During the process of drying they are carefully watched and examined by boys, to keep them from the ravages of insects. When sufficiently desiccated the cakes of opium are packed in casks, and are ready for the market.

The yield of morphia from East Indian opium is usually very small, a circumstance which Messrs Flückiger and Hanbury conceived to be partly due to the climate and partly to the defective method of cultivation.

He believed that the period, three or four weeks, during which the juice was allowed to remain in the wet state was much too long, and exercised a destructive influence on its constituents.

Opium from England, France, and Germany is occasionally met with, but never in considerable quantity. The cultivation of the opium poppy, however, in these three countries is chiefly carried on for the sake of the capsules which are largely employed in medicine; and the oil extracted from the seed, which is highly valued and extensively employed by artists.

_Pur._ The opium of commerce is not unfrequently adulterated with extract of poppies, extract of lettuce, lactucarium, mucilage of gum tragacanth, dried leaves, starch, water, clay, sand, gravel, and other substances, in order to increase its weight. This fraud is readily detected by inspection, by chemical analysis, and the microscope; and indirectly, with the greatest certainty, by a simple assay of the sample for its morphia (morphiometry). This may be effected by one or other of the following methods:——

1. (Couerbe.) Opium, 4 parts, and quicklime, 1 part, made into a milk with water, q. s., are boiled together, and the solution filtered whilst hot; the filtrate is then saturated with dilute hydrochloric acid and the morphia precipitated by the addition of ammonia, any excess of the latter being expelled by heat; the precipitate is then collected, dried, and weighed. If 100 gr. have been operated on, the given weight will represent (nearly) the per-centage richness of the sample in morphia.

2. (Guilliermond.) 100 gr. of opium are triturated for some time in a mortar along with 4 times its weight of rectified spirit, and the tincture strained through linen, with expression, into a wide-mouthed bottle; the marc is triturated a second time with about 3 times its weight of alcohol, and the tincture strained into the bottle as before; to the mixed tincture is added a fl. dr. of liquor of ammonia, and the whole is agitated for a short time. In about 12 hours the morphia spontaneously separates, accompanied with some narcotina and meconate of ammonium; the morphia covering the interior of the vessel with large, coloured, and gritty crystals, feeling like sand, and the narcotina crystallising in very light, small, white, and pearly needles. These crystals are washed with water, either through a paper filter or linen, to free them from the meconate of ammonia which they contain; after which the narcotina is separated from the morphia by decantation in water, which removes the narcotina, which is the lighter of the two. According to M. Mialhe, however, the morphia is more effectually removed by washing the crystals with 1 to 1-1/2 fl. dr. of ether, by triturating the two together, when the morphia is left in an insoluble state, and may then be dried and weighed.

3. (B. Ph.) Take of opium, 100 gr., slaked lime, 100 gr., distilled water, 4 oz. Break down the opium and steep it in an ounce of the water for 24 hours, stirring the mixture frequently. Transfer it to a displacement apparatus, and pour on the remainder of the water in successive portions, so as to exhaust the opium by percolation. To the infusion thus obtained, placed in a flask, add the lime, boil for ten minutes, place the undissolved matter on a filter, and wash it with an ounce of boiling water. Acidulate the filtered fluid slightly with hydrochloric acid, evaporate it to the bulk of 1/2 an ounce, and let it cool. Neutralise it cautiously with solution of ammonia, carefully avoiding an excess; remove by filtration the brown matter which separates, wash it with an ounce of hot water, mix the washings with the filtrate, concentrate the whole to the bulk of 1/2 an ounce, and add now solution of ammonia in slight excess. After 24 hours collect the precipitated morphia on a weighed filter, wash it with cold water, and dry it at 212°. It ought to weigh at least from 6 to 8 grains.

4. (Cleaver.) Commenting on the above method of opium assay, Mr Cleaver[75] remarks:——“This process, if properly and carefully carried out, is one of the best, as, by the use of lime, the resin and meconate of calcium, also meconic acid, are removed from solution. The objections to it are——

[Footnote 75: ‘Pharmaceutical Year Book,’ 1876.]

“_a._ That the large quantity of water used, and the subsequent evaporation, cause loss of morphia.

“_b._ That no account is taken of the loss of morphia by non-precipitation.

“The modifications I would introduce are as follows:——

“_a._ The opium should be first treated with bisulphide of carbon or benzine.

“_b._ The dried residue should then be mixed with its own weight of lime and two or three times its bulk of some inert powder, such as pumice or glass. It is then to be percolated with water, the first part of the percolate being returned as fast as it runs through. By this means much less water will be required to exhaust the opium than would otherwise be the case.

“After the opium has been exhausted, which will be known by the liquid dropping through devoid of taste, the solution should be exactly neutralised with dilute sulphuric acid and filtered and the precipitate washed. The clear solution is then to be evaporated over a water bath until its bulk is about 1/2 an ounce, and again filtered if requisite, then ammonia is to be added in slight excess, and the liquid allowed to stand for 24 hours.

“The precipitate can then be collected, washed with ether and dried, and to the amount formed must be added the amount corresponding to the quantity of water used in precipitating and washing.

“The morphia obtained by this process is of a dull white colour, crystalline, perfectly soluble in alcohol, acids, and alkalies.”

5. (Prollius.) This is a very simple process and is said to give very exact results. It is as follows:——The opium is exhausted with 9 or 10 times its weight of spirit of 34 per cent. strength. Of the resulting tincture, 100 parts are well shaken with 5 parts of ether and 2 parts of solution of ammonia in a stoppered bottle, and then allowed to stand from 12 to 24 hours. The liquids separate slowly, and retain, partly in the ether, partly in the alcoholic liquid, the colouring matter, narcotine, and other crystallisable constituents of opium; while the morphia separates in crystals between the two layers, and finally sinks to the bottom. The fluid portion is decanted, the crystals are washed with diluted alcohol, dried and weighed.

6.[76] (Teschemacher.) In employing the following method the use of alcohol to extract the morphia is avoided, and meconic acid is separated at an early stage, which prevents the formation of a basic meconate on precipitation of the morphia. Two special reagents are required for this process; the one prepared by mixing 1 part of ammonia, sp. gr. 0·880, with 20 parts of methylated alcohol, and digesting in this mixture a large excess of morphine; this, when filtered, is termed “_morphiated spirit_;” the other, _morphiated water_, is water saturated with excess of morphine, and contains 0·04 per cent. of this alkaloid. 1000 gr. of opium are macerated for 12 to 24 hours in about 4000 grains of cold distilled water, together with 300 gr. of lead acetate, stirring the mixture from time to time. This separates the meconic acid as lead meconate, whilst the morphia is dissolved in the acetic acid set free.

[Footnote 76: ‘Chemical News,’ xxxv, 47.]

After this maceration the opium may be readily ground in a mortar to a paste, and so much more cold distilled water added, raising the pestle and mortar with successive portions of it as to fill with the mixture a measure = 20,250 grains of distilled water; experience has shown that the space occupied by the insoluble matters measures from 200 to 300 gr., so that the limit of possible error, by averaging and allowing 250 gr. for the insoluble portion, amounts to 0·05% in opium containing 10% of morphia. The mixture is to be filtered and 15,000 measured gr. = 750 grains of opium, of the clear solution, are to be evaporated to an extract on a water bath, and this residue to be drenched with 3090 gr. of boiling alcohol or methylated spirit, and the whole digested, with frequent stirring, for about 10 minutes.

This separates the gum, &c., of the opium which is insoluble in alcohol, and so far frees the solution of morphia from impurity.

At this stage of the process it is well to get rid of the excess of lead-salts, and to accomplish this, sulphuric acid is preferable to sulphuretted hydrogen. So much diluted sulphuric acid as may be equal to 30 gr. of oil of vitriol will almost always be sufficient for this purpose, any excess of acid being converted into sulphate of ammonia by the subsequent addition of so much solution of ammonia as shall be equivalent to the 30 gr. of oil of vitriol, thus forming a salt but slightly soluble in the alcoholic solution. This mixture may now be transferred to a beaker and allowed to settle for 12 hours, after which it is to be filtered, and the filter and insoluble residue thoroughly washed with alcohol or methylated spirits. This alcoholic filtrate is then distilled, or evaporated on a water bath, to about 1000 gr.; and mixed, while still hot, with 400 gr. of solution of ammonia, sp. gr. 0·880, stirring rapidly and continuously for at least 20 minutes, whilst the beaker or evaporating dish should be cooled as rapidly as possible by immersion in an external vessel filled with cold water. The rapid and continuous stirring is most important, as the precipitation of the whole of the morphia _in fine powder_ is thereby effected, instead of the granular or mamillated condition so frequently met with, and it thus permits of the easy and thorough separation of all the narcotine which may be mixed with the morphine. When the cooling of the mixture and precipitation of the morphia is thus attained, transfer it quickly and completely to a filter of sufficient capacity to hold the whole, and when the liquid portion has passed through, wash the remainder of the precipitated morphia adhering to the dish or beaker on to the filter, using for this purpose the morphiated spirit already described, and continuing the washing of the precipitate until it is completely freed from the mother-liquor. To do this effectually requires some little care: thus the morphia on the filter must be kept in a spongy condition and never allowed to cohere, which is easily effected by pouring the morphiated spirit round the edges of the filter, so as not to disturb the precipitate, which must not be permitted to drain or solidify until this washing is completed.

The precipitate is now to be washed from off the filter-paper with the morphiated water previously described, and digested therein for a few minutes, which removes some more colouring matter, together with any salts soluble in water, but insoluble in alcohol, which may have adhered to the precipitated morphia; then once more collect the precipitate on a filter, washing it with morphiated spirit, after this once with ether, and finally thrice, or more with benzine; this completely frees it from narcotina, which is very soluble in benzine; morphia, on the contrary, being insoluble in this liquid. It now remains to drain and dry at a low temperature, say 100° F., the resulting pure and white morphia, the weight of which will indicate the amount of this alkaloid present in 750 gr. of the opium under examination.

7. (Ph. E.) Macerate 100 gr. of opium for 24 hours in 2 fl. oz. of water, filter, and strongly squeeze the residue; then precipitate the infusion with carbonate of sodium, 1/2 oz., dissolved in cold water, 2 fl. oz.; gently heat the precipitate until it shrinks and fuses, then cool and weigh it. It should weigh at least 10 gr., and, when powdered, be entirely soluble in a solution of oxalic acid. See also Watts’ ‘Dic. of Chemistry,’ article OPIUM.

_Tests._ These depend chiefly on the chemical and physical characters of morphia and meconic acid, the tests for which have been already noticed. In operating upon the contents of the stomach, or upon solid organs, in cases of suspected poisoning, the best method or proceeding is that already described under ALKALOID.

Another method is to boil the substances in water slightly acidulated with acetic acid, next to evaporate the solution to the consistence of a thick syrup, and then to treat it twice with boiling rectified spirit; the tincture thus obtained is to be filtered when cold, and again evaporated to the consistence of a syrup; it is now re-dissolved in distilled water, the filtrate treated with solution of subacetate of lead, and the precipitate of meconate of lead, separated by filtration, and carefully preserved. A current of sulphuretted hydrogen is then passed through the solution to precipitate excess of lead, and after again filtering it the liquid is evaporated, at first in a water bath, and afterwards under the receiver of an air-pump. The shapeless mass of crystals thus obtained present all the characters of morphia, if the substance examined contained opium. In the meantime the precipitate of meconate of lead is to be boiled with water acidulated with sulphuric acid, and the insoluble sulphate of lead separated by filtration; the filtered liquid, by evaporation, furnishes meconic acid, either under the form of crystals or an amorphous powder, the solution of which precipitates ferric salts of a deep blood-red.

The following are additional tests to those already noticed:——

1. From the peculiar odour of opium, often perceptible when the drug has been taken only in very small quantities.

2. A solution containing crude opium is turned of a deep red colour, or if coloured, it is turned of a reddish brown, and is darkened by tincture of ferric chloride.

3. (Hare.) A portion of the suspected liquid is poured into a beaker glass, and a few drops of solution of acetate of lead are added to it; the whole is stirred frequently for 10 or 12 hours, and then allowed to settle, after which the supernatant liquid is decanted; 20 or 30 drops each of dilute sulphuric acid and solution of ferric sulphate are next poured on the precipitate (meconate of lead), when a deep and beautiful red colour will be developed if the original liquid contained opium.

4. (Dr Rieget.) The suspected substance is mixed with some potassa, and is then agitated with ether; a strip of white unsized paper is next several times moistened with the solution, and when dry it is re-moistened with hydrochloric acid, and exposed to the steam of hot water. The paper assumes a red colour, more or less deep, if opium is present.

_Uses, &c._ Opium is one of the most valuable substances employed in medicine. In small doses it acts as a powerful and diffusible stimulant, in somewhat larger ones it is narcotic, and in excessive doses it proves an active narcotic poison. It is also anodyne, antispasmodic, diaphoretic, soporific, and sedative, its peculiar action being greatly modified by the dose and the condition of the patient. Its action as a stimulant is followed by sedative effects, which are, in general, much more marked than could be expected from the degree of previous excitement it induces. It is employed to fulfil a variety of indications——to procure sleep, to lull pain, allay irritation, check morbid discharges, alleviate cough and spasm, &c. &c. It also, when judiciously administered, renders the body less susceptible of external impressions, as those of cold, contagion, &c.; but it is injurious when the pulse is high, the heat of the body above the natural standard, and the skin dry, or when there is a disposition to local inflammation or congestion. When applied externally, in the form of frictions, liniments, ointments, &c., it is absorbed, and produces similar effects to those produced by swallowing it, but in this way it requires to be used in larger quantities.——_Dose._ As a stimulant, 1/4 gr., every 2 or 3 hours; as an anodyne and antispasmodic, 1/2 to 1 gr.; as a soporific, 1/2 to 2 gr.; in violent spasms, neuralgia, acute rheumatism, &c., 2 to 4 gr., increased in delirium tremens, hydrophobia, mania, tetanus, &c., to several times that quantity, according to circumstances.

The use of opium as a stimulant and intoxicant is common among the nations of the East. The Turks chew it, and the Chinese smoke a watery extract of it, under the name of ‘chundoo,’ the preparation of which from the crude article constitutes a special business. Messrs Flückiger and Hanbury, in their ‘Pharmacographia,’ published in 1874, say this particular business is not confined to the celestials, since, in 1870, a British firm at Amoy opened an establishment for preparing chundoo for the consumption of the Chinese in California and Australia.

The qualities most valued by the Chinese in opium are its fulness and peculiarity of aroma, and its degree of solubility. The amount of morphine it contains is a secondary consideration.

The practice of opium smoking yearly increases in China. It appears to be openly followed, and no odium attaches to it, provided it is not carried so far as to intoxicate or incapacitate the smoker.

In the larger cities and towns adjacent to Amoy the proportion of opium smokers, according to Mr Hughes, Commissioner of Customs at Amoy, is estimated at from 15 to 20 per cent. of the adult population.

In the country districts 5 to 10 per cent. of the population are believed to be opium smokers.

In many of the Western States of America the practice has become so notoriously common that in 1872 the legislature of Kentucky passed a bill by which any person who, through the excessive use of opium, is incapacitated from managing himself or his affairs, may, upon the affidavit of two citizens, be confined in an asylum, and subjected to the same restraint as lunatics or habitual drunkards.[77]

[Footnote 77: Blythe.]

Of late years opium-eating and laudanum-taking have, unfortunately, been greatly on the increase in this country, and the employment of this drug as a soporific for infants and young children has become so general amongst the poor and dissipated as to call for the interference of the legislature.

Of the 250,000 lbs. of opium which, as shown by the recent returns made by the Custom House, are imported into this country, it has been computed that not more than a third of this quantity is used for medicinal purposes.

According to Dr Chevers the practices of opium-eating and opium-smoking are very common among the natives of India. The same authority also states that in that country a large number of female infants are purposely poisoned by it, by introducing the drug into the child’s mouth, and in various other ways.

The first effect of opium as a stimulant is to excite the mental powers and to elevate those faculties proper to man; but its habitual use impairs the digestive organs, induces constipation, and gradually lessens the energy of both the mind and body. In excessive quantities it destroys the memory, induces fatuity and a state of wretchedness and misery, which after a few years is mostly cut short by a premature death. In this respect the effects of the excessive use of opium closely resemble those of fermented liquors.

Opium is somewhat uncertain in its action; some persons being able, sometimes from idiosyncrasy, but more frequently from previous indulgence in it, to take a much larger dose than others. The smallest quantity which is said to have proved fatal with an adult is 4 grains of the crude opium. In contrast with this may be quoted the statement of Dr Garrod, of a young man who not only swallowed 60 gr. of Smyrna opium night and morning, but very frequently, in addition to this, 1 oz. to 1-1/2 oz. of laudanum during the day.

Dr Chapman also cites the case of a patient to whom a wineglass of laudanum had to be administered several times in 24 hours.

_Pois._——_Symptoms._ Headache; drowsiness; stupor; frightful reveries; vertigo; contracted pupil (generally); scanty urine; pruritus or dry itching of the skin, often accompanied by a papular eruption; thirst; dryness of mouth and throat; weak and low pulse; vomiting; respiration, generally, natural. Sometimes the drowsiness or sleep is calm and peaceful.——_Ant., &c._ Vomiting must be induced as soon as possible, by means of a strong emetic and tickling the fauces. If this does not succeed, the stomach-pump should be applied. The emetic may consist of a 1/2 dr. of sulphate of zinc dissolved in 1/2 pint of warm water, of which one third should be taken at once, and the remainder at the rate of a wine-glassful every 5 or 10 minutes, until vomiting commences. When there is much drowsiness or stupor, 1 or 2 fl. dr. of tincture of capsicum will be found a useful addition; or one of the formulæ for emetic draughts given at page 588 (especially No. 7) may be taken instead. Infusion of galls, cinchona, or oak-bark, should be freely administered before the emetic, and water soured with vinegar and lemon-juice, after the stomach has been well cleared out. To rouse the system, spirit-and-water or strong coffee may be given. To keep the sufferer awake, rough friction should be applied to the skin, an upright posture preserved, and walking exercise enforced, if necessary. When this is ineffectual, cold water may be dashed over the chest, head, and spine, or mild shocks of electricity may be had recourse to. To allow the sufferer to sleep is to abandon him to destruction. Bleeding may be subsequently necessary in plethoric habits, or in threatened congestion. The costiveness that accompanies convalescence may be best met by aromatic aperients; and the general tone of the habit restored by stimulating tonics and the shower bath. The smallest fatal dose of opium in the case of an adult within our recollection was 4-1/2 gr. Children are much more susceptible of the action of opium than of other medicines, and hence the dose of it for them must be diminished considerably below that indicated by the common method of calculation depending on the age. See DOSES, &c.

_Concluding Remarks._ Opium is a very complicated substance, and contains a number of alkaloids and other proximate vegetable principles, besides a certain portion of saline matter. The substances already detected in it are caoutchouc, codein, fatty matter, lignin, meconic acid, meconia, morphia, narceia, narcotia, odorous matter, opiania, papaveria, pseudomorphia (?), porphyroxin, resin, saline matter, &c. It is doubtful, however, whether some of these substances are not generated from other principles existing in opium during the processes adopted to obtain them.

According to Mulder, 100 parts of ordinary Smyrna opium contain——

Morphia 10·842 Codeia ·678 Narcotia 6·808 Narceia 0·662 Meconia ·804 Meconic acid 5·154 Resin 3·582 Gummy matter 26·242 Mucus 19·086 Fatty matter 2·166 Caoutchouc 6·012 Water 9·846 Matter undetermined and loss 2·118 ———————— 100·

The sp. gr. of Smyrna opium is 1·336.

The following chart, showing the natural alkaloids of opium and a few of their artificial derivatives, is taken from the ‘Pharmacographia’ of Messrs Flückiger and Hanbury:——

+----------------+----------------------------------------------------+——+——+——+——+ | | |C.|H.|N.|O.| |Discovered by | COTARNINE |12|13| 1| 3| | Wöhler, 1844 |Formed by oxidising narcotine, soluble in water. | | | | | | | | | | | | |Hesse, 1871 | 1. Hydrocotarnine |12|15| 1| 3| | | Crystallisable, alkaline, volatile at 100°. | | | | | | | | | | | | |Matthiesen and | APORMORPHINE |17|17| 1| 2| | Wright, 1869 |From morphine by hydrochloric acid, colourless, | | | | | | | amorphous, turning green by exposure to air, | | | | | | | emetic. | | | | | | | | | | | | |Wright, 1871 | DESOXYMORPHINE |17|19| 1| 2| | | | | | | | |Sertürner, 1816 | 2. Morphine |17|19| 1| 3| | | Crystallisable, alkaline, levogyre. | | | | | | | | | | | | |Pelletier and | 3. Pseudomorphine |17|19| 1| 4| | Thibouméry, |Crystallises with H_{2}O, does not unite even with | | | | | | 1835 | acetic acid. | | | | |

+----------------+----------------------------------------------------+——+——+——+——+ | Discovered by | |C.|H.|N.|O.| |Matthiesen and | APOCODEINE |18|19| 1| 2| |Burnside, 1871 |From codeine by chloride of zinc; amorphous, | | | | | | | emetic. | | | | | | | | | | | | |Wright, 1871 | DESOXYCODEINE |18|21| 1| 2| | | | | | | | |Robiquet, 1832 | 4. Codeine |18|21| 1| 3| | | Crystallisable, alkaline, soluble in water. | | | | | | | | | | | | |Matthiesen and | NORNARCOTINE |19|17| 1| 7| |Foster, 1868 | | | | | | | | | | | | | |Thibouméry, 1835| 5. Thebaine |19|21| 1| 3| | |Crystallisable, alkaline, isomeric with buxine. | | | | | | | | | | | | |Hesse, 1870 | THEBENINE |19|21| 1| 3| | | | | | | | |Hesse, 1870 | THEBARCINE |19|21| 1| 3| | |From Thebaine or Thebenine by hydrochloric acid. | | | | | | | | | | | | |Hesse, 1871 | 6. Protopine |20|19| 1| 5| | | Crystallisable, alkaline. | | | | | | | | | | | | |Matthiesen and | METHYLNORNARCOTINE |20|19| 1| 7| |Foster, 1868 | | | | | | | | | | | | | |Hesse, 1871 | DEUTEROPINE |20|21| 1| 5| | | Not yet isolated. | | | | | | | | | | | | |Hesse, 1870 | 7. Laudanine |20|25| 1| 4| | |An alkaloid, which, as well as its salts, forms | | | | | | | large crystals; turns orange by hydrochloric acid.| | | | | | | | | | | | |Hesse, 1870 | 8. Codamine |20|25| 1| 4| | |Crystallisable, alkaline, can be sublimed; becomes | | | | | | | green by nitric acid. | | | | | | | | | | | | |Merck, 1848 | 9. Papaverine |21|21| 1| 4| | |Crystallisable, also its hydrochlorate; sulphate in | | | | | | | sulphuric acid precipitated by water. | | | | | | | | | | | | |Hesse, 1865 | 10. Rhœadine |21|21| 1| 6| | |Crystallisable, not distinctly alkaline, can be | | | | | | | sublimed; occurs also in Papaver Rhœas. | | | | | | | | | | | | |Hesse, 1865 | RHŒAGENINE |21|21| 1| 6| | |From rhœadine, crystallisable, alkaline. | | | | | | | | | | | | |Armstrong, 1871 | DIMETHYLNORNARCOTINE |21|21| 1| 7| | | | | | | | |Hesse, 1870 | 11. Meconidine |21|23| 1| 4| | |Amorphous, alkaline, melts at 58°, not stable, the | | | | | | | salts also easily altered. | | | | | | | | | | | | |T. and H. Smith,| 12. Cryptopine |21|23| 1| 5| |1864 |Crystallisable, alkaline, salts tend to gelatinise, | | | | | | | hydrochlorate crystallises in tufts. | | | | | | | | | | | | |Hesse, 1871 | 13. Laudanosine |21|27| 1| 4| | | Crystallisable, alkaline. | | | | | | | | | | | | |Derosne, 1803 | 14. Narcotine |22|23| 1| 7| | |Crystallisable, not alkaline, salts not stable. | | | | | | | | | | | | |Hesse, 1870 | 15. Lanthopine |23|25| 1| 4| | |Microscopic crystals, not alkaline, sparingly | | | | | | | soluble in hot or cold spirit of wine, ether or | | | | | | | benzol. | | | | | | | | | | | | |Pelletier, 1832 | 16. Narceine |23|29| 1| 9| | |Crystallisable (as a hydrate), readily soluble in | | | | | | | boiling water, or in alkalies, levogyre. | | | | | +----------------+----------------------------------------------------+——+——+——+——+

⁂ The following preparations, once famous, are now nearly obsolete in this country. Those that are made with cold water or by fermentation are supposed to be milder than crude opium, and in this respect to be similar to ‘BLACK DROP,’

=Opium, Homberg’s.= Opium exhausted by repeated coction in 10 or 12 times its weight of water, and the mixed liquors evaporated to one third, and kept boiling for 2 or 3 days, adding water from time to time, then straining and evaporating to a pilular consistence. BAUMÉ’S PURIFIED OPIUM is similar.

=Opium, Launcelotte’s.= Opium, 1 lb.; quince juice, 1 gall.; pure potassa, 1 oz.; sugar, 4 oz.; ferment for some time, evaporate to a syrup, digest in rectified spirit, filter, and evaporate the tincture.

=Opium, Let′tuce.= Lactucarium.

=Opium, Newmann’s.= Infusion of opium, strained, mixed with a little sugar, and fermented for some months in a warm place; and, lastly, strained and evaporated to an extract, or preserved in the liquid form.

=Opium, Powell’s.= Opium, exhausted by coction with water, the residuum treated with spirit of wine, and the mixed tincture and decoction evaporated to an extract.

=Opium, Pu′′rified.= _Syn._ OPIUM PURIFICATUM, L. The purified opium of old pharmacy is now represented by the aqueous extract of the Pharmacopœias. (See page 703.) Formerly, picked opium, beaten to a pilular consistence, with the addition of a little water or proof spirit, was called ‘SOFT PURIFIED OPIUM’ (OPIUM PURIFICATUM MOLLE); and picked opium, dried in a water bath until brittle enough for powdering, was called ‘HARD PURIFIED OPIUM’ (O. P. DURUM). CORNETTE’S and JOSSE’S PURIFIED OPIUM are similar to the extract of Ph. L.

=Opium, Quercetan’s.= Vinegar of opium evaporated to an extract.

=Opium, Strained.= _Syn._ EXTRACTUM THEBAICUM, OPIUM COLATUM, OPIUM PURIFICATUM, L. Opium dissolved or softened in an equal weight of water, passed through canvas, and evaporated to the consistence of an extract. It is now superseded by the aqueous extract.

=Opium, Tor′refied.= _Syn._ ROASTED OPIUM; OPIUM TORREFACTUM, L. Opium, dried, cut into thin slices, and roasted on an iron plate, at a low heat, as long as it emits vapours, care being taken not to burn it.

=OPODEL′DOC.= 1. See LINIMENT OF SOAP.

2. (STEER’S OPODELDOC.) This, which differs from common opodeldoc chiefly in containing more soap, is prepared as follows:——

_a._ White Castile soap (cut very small), 2 lbs.; camphor, 5 oz.; oil of rosemary, 1 oz.; oil of origanum, 2 oz.; rectified spirit, 1 gall.; mix, and digest in a strong bottle (closely corked), by the heat of a water bath, until solution is complete; when the liquid has considerably cooled, add of liquor of ammonia, 11 oz., and immediately put it into wide-mouthed bottles (Steer’s), cork them close, and tie them over with bladder. Very fine, solid and transparent when cold.

_b._ Soap, 4 oz.; camphor, 1 oz.; oil of rosemary and origanum, of each 1 dr.; rectified spirit, 1 pint; liquor of ammonia, 1-1/2 fl. oz. Mix.

_c._ (Phil. Coll. of Phar.) White soap, 28 oz.; camphor, 8 oz.; rectified spirit, 6-1/2 pints; dissolve, suffer the impurities to subside, add of liquor of ammonia, 4 fl. oz.; oils of rosemary and horsemint, of each 1 fl. oz.; and pour it into phials, as before.

=OPOPONAX.= A resinous substance obtained from the roots of the _Opoponax chironium_. It occurs in lumps of a reddish-yellow or brown colour, and has a waxy fracture. It has a powerful odour, which somewhat resembles garlic, and a bitter taste.

Opoponax is only partially soluble in alcohol, According to Payen it consists of a little volatile oil, a resin that melts it at 100° C., gum, inorganic and organic salts, and mechanical admixtures. It is used in French pharmacy; and was held in great esteem by Hippocrates, Theophrastus, and Dioscorides, all of whom employed it therapeutically.

=ORANGE.= _Syn._ AURANTIUM, L. The common SWEET ORANGE is the fruit of _Citrus Aurantium_. The SEVILLE or BITTER ORANGE is produced by _Citrus vulgaris_ or _Bigaradia_.

Oranges are probably about the most wholesome and useful of all the subacid fruits. Their juice differs from that of lemons chiefly in containing less citric acid and more sugar. In their general properties the two are nearly similar.

FACTITIOUS ORANGE JUICE is made by dissolving citric acid, 1 oz., and carbonate of potassa, 1 dr., in water, 1 quart, and digesting the solution on the peel of half an orange until sufficiently flavoured; Narbonne honey or white sugar is then added to impart the necessary sweetness. Instead of orange peel, 5 or 6 drops of oil of orange peel, with 1/2 fl. oz. of tincture of orange peel, may be used.

ORANGE PEEL (CORTEX AURANTII) is an agreeable, stomachic, bitter tonic, especially useful as an adjunct to more active medicines. That ordered to be used in medicine is the exterior (yellow) rind of the _Citrus Bigaradia_, or bitter orange, dried in the months of February, March, or April. See CANDYING, INFUSION, ISSUE PEAS, OILS (volatile), &c.

=ORANGEADE′.= _Syn._ ORANGE SHERBET. 1. Juice of 4 oranges, thin peel of 1 orange, lump sugar, 4 oz.; boiling water, 3 pints.

2. Juice and peel of 1 large orange, citric acid, 15 gr.; sugar, 3 oz.; boiling water, 1 quart.

=Orangeade, Effervescing or Aerated.= 1. Mix 1 lb. of syrup of orange peel, a gallon of water, and 1 oz. of citric acid, and charge it strongly with carbonic acid gas with a machine.

2. Syrup of orange juice, 3/4 fl. oz.; aerated water, 1/2 pint.

3. Simple syrup, 1/2 fl. oz.; tincture of orange peel, 1/2 dr.; citric acid, 1 scruple; fill the bottle with aerated water.

4. Put into a soda-water bottle 1/2 oz. to 1 oz. of syrup of orange peel, 30 gr. of bicarbonate of potash, 8 oz. of water, and, lastly, 40 gr. of citric acid, in crystals, and cork immediately.

5. Put into each bottle 2 or 3 dr. of sugar, 2 drops of oil of orange peel, 30 gr. of bicarbonate of potash, or 25 gr. of bicarbonate of soda water to fill the bottle, and 40 gr. of citric acid, as before.

=OR′ANGE CHROME.= _Prep._ 1. From a solution of chromate of potash and diacetate of lead, as chrome yellow.

2. From chrome yellow or chromate of lead, by acting on it with a weak alkaline lye, until sufficiently darkened. Used as a pigment.

=ORANGE DYES.= These are produced from mixtures of red and yellow dyes in various proportions; or by passing the cloth, previously dyed yellow, through a weak red bath.

1. A very good fugitive orange may be given with annotta, by passing the goods through a solution made with equal parts of annotta and pearlash, or, still better, through a bath made of 1 part of annotta, dissolved in a lye of 1 part each of lime and pearlash and 2 parts of soda. The shade may be reddened by passing the dyed goods through water acidulated with vinegar, lemon juice, or citric acid, or through a solution of alum. The goods are sometimes passed through a weak alum mordant before immersion in the dye bath.

2. (For COTTON.) For 40 lbs. 2-1/2 lbs. annotta, 24 lbs. of bark, 3 quarts of chloride of tin. Boil the annotta, put off the boil, enter and wince until it has a good body. Then wring out, wash well, wring again, and shake out. Next, in a clean boiler, boil the bark in a bag for a quarter of an hour, add the chloride of tin, and enter, wince at the spring till the required shade is got.

3. (For SILK.) For 10 yards. Annotta, 1-3/4 oz.; bark, 1-1/4 oz.; chloride of tin, 1-1/2 oz. Give a good body of annotta at 212° Fahr.; wash in one water, then top with the bark and chloride of tin.

4. (For WOOL.) For 50 lbs. Boil 10 lbs. of bark and 1-1/2 lbs. of cochineal; add 2 lbs. of tartar, 2-1/2 quarts of yellow spirits. Enter at 200° Fahr.; boil 30 minutes. See ANNOTTA, DYEING, &c.

=ORANGE RED.= _Syn._ SANDIX. From white lead, by calcination, in a nearly similar manner to that by which red lead is prepared from the protoxide. Brighter than red lead. Used wholly as a pigment.

=OR′ANGERY.= The gallery, building, or enclosure in a garden, in which orange trees are preserved or cultivated, to shield them from the effects of the external winter, or to assist their growth by artificial heat.

=OR′CHARD.= See CIDER.

=OR′CEIN.= C_{7}H_{7}NO_{2}. _Syn._ LICHEN LAKE. A brownish-red powder, obtained by dissolving orcin in ammonia, exposing the solution to the air, and then precipitating with dilute acetic acid. It is nearly insoluble in water, but dissolves freely in solutions of ammonia and the fixed alkalies, with the production of a rich purple or violet colour. It probably constitutes the leading tinctorial ingredient in ARCHIL, CUDBEAR, and LITMUS. (See _below_.)

=OR′CHIL.= See ARCHIL.

=OR′CIN.= C_{7}H_{8}O_{2}. The general product of the decomposition of the acids obtained from the tinctorial lichens under the influence of heat or the alkaline earths.

_Prep._ 1. The powdered lichen is treated with boiling alcohol, the tincture filtered whilst hot, and again after it has become cold; the alcohol is then removed by distillation, and the remainder evaporated to the consistence of a syrup; this is redissolved in water, and the solution is again filtered and evaporated to a syrup; it is then set aside some days in a cool place, and the crystals of orcin which form are collected, and dried by pressure in bibulous paper. Impure.

2. Lecanoric or orsenillic acid (impure will do) is boiled in baryta water, and the excess of baryta is precipitated by carbonic acid; the filtered liquid is then evaporated to a small bulk, and set aside to crystallise, as before.

_Prop., &c._ Large, square, prismatic crystals; slightly yellowish; intensely sweet; very soluble in both water and alcohol; melt to a syrupy liquid, and then distil unchanged. Alkalies decompose it; when exposed to the air, it gradually reddens. (See _above_.)

=OREIDE.= A variety of brass, in appearance very much like gold. The following, according to MM. Menrier and Valient, its inventors, is the composition of this alloy:——Copper, 100 parts; zinc, 17 parts; magnesia, 6 parts; sal ammoniac, 3·6 parts; quicksilver, 1·80 parts; tartar of commerce, 9 parts. The copper being first melted, the other ingredients are added by small portions at a time, the whole being kept in fusion for about half an hour, and during which time they are kept skimmed. The oreide has a fine grain, is malleable, is capable of being brilliantly polished, and has its lustre restored by the use of acidulated water.

=OR′ELLIN.= A yellow colouring matter contained together with bixin in annotta. It is soluble in water and in alcohol, slightly soluble in ether, and dyes alumed goods yellow. Also the name sometimes given to purified annotta. The commercial annotta is dissolved in an alkaline solution, either caustic or carbonated, and then precipitated by an acid. See ANNOTTA.

=ORES.= The mineral bodies from which metals are obtained. The processes adopted for this purpose constitute OPERATIVE METALLURGY; those by which their value is determined, MINERAL ASSAYING.

A very small proportion only of the metals are met with in nature in the free or elementary condition, by far the greater number found being united with some non-metallic element or elements, in definite atomic proportions, and as such forming true chemical compounds, in which in almost every instance the physical and chemical properties of the metal are obliterated. In these bodies, which, when they are used as sources of the metals commonly employed by man, are called ORES, the metal is mostly combined with oxygen or sulphur, sometimes with carbonic acid, and less frequently with chlorine, and other negative elements. Thus we have the native combinations of iron and oxygen constituting the minerals known as hæmatite iron ore (Fe_{2}O_{3}), bog iron ore (Fe_{2}O_{3},3H_{2}O), and magnetic iron ore (Fe_{2}O_{3},FeO), of tin and oxygen in tin stone (SnO_{2}), and of copper and oxygen known as red copper ore (Cu_{2}O). Of the principal ores into which sulphur enters as a chemical ingredient, we may mention native sulphide of antimony (Sb_{2}S_{3}); the two native sulphides of arsenic, realgar (As_{2}S_{2}) and orpiment (As_{2}S_{3}); galena, or native sulphide of lead (PbS), blende, or native sulphide of zinc (ZnS), and cinnabar, or native sulphide of mercury (HgS). Besides the above, there are also certain double native sulphides, such as the double sulphide of iron and copper, known as Peacock ore, and having the composition Fe_{2}S_{3},3Cu_{2}S; iron and copper pyrites (Fe_{2}S_{3},Cu_{2}S); and red silver ore (Sb_{2}S_{3},3AgS).

In the state of carbonate, ores occur——as malachite native carbonate of copper (CuCO_{3}.Cu(HO)_{2}), as calamine, or native carbonate of zinc (ZnCO_{3}), and as spathose iron ore, or native carbonate of iron (FeCO_{3}). Horn silver and horn lead, the former having the composition AgCl, and the latter PbCO_{3} + PbCl_{2} are illustrations of ores containing chlorine.

The process of obtaining the metal from the ore of course varies with the nature and character of the latter. Before, however, this operation can be undertaken, the ore itself is subjected to certain mechanical operations, in order to remove the gangue or the adhering earthy, rocky, stony, and other matters with which it is always more or less mixed up. The amount of attention which is given to this preparatory treatment of the ores greatly depends upon their value; those, for instance, of copper and lead as commanding a higher market price than those of zinc and iron being submitted to commensurate treatment. This process of freeing the ores from the gangue, which is termed dressing, is generally conducted as follows, mostly near the pit entrance of the mine whence the ores have been extracted.

If the material brought up to the pit’s mouth is a lead or a copper ore, it mostly contains a number of lumps, which are considered sufficiently pure for the smelting oven, and these are set aside without being dressed. Generally, however, the ore is first broken by hammers into pieces about as large as a walnut, and the best pieces are then selected for smelting.

The remaining or inferior portions are then crushed under the large and horizontal cylinders of a grinding mill, to which they are supplied by hoppers. After being ground the ore is separated by being made to pass through coarse sieves, the coarser portions being set aside for the stampers, whilst the finer ones are subjected to the operation of jigging. This consists in a workman separating the contents of the sieve under water by imparting to them such a movement that the bits of ore (particularly if they are of a friable nature like galena) become broken, and thus pass through the meshes of the sieve to the bottom of the water, whilst the less friable and specifically lighter matter, mostly consisting of gangue, remains behind on the sieve. This residue, being mixed with the coarser portions resulting from the first sifting, and which have not been subjected to the jigging process, is transferred to the stamping mill, whilst those portions of ore found at the bottom of the well are reserved for smelting. If the ore be one containing tin, it does not undergo the above processes, but passes at once to the stamping apparatus.

This stamping apparatus consists of five or six large wooden beams, each weighing 1/8th of a ton. Each beam is covered at the bottom with iron, and is made to rise and fall in succession by means of projections from a horizontal axle, made to revolve either by water or steam power. Behind the stampers is an inclined board, upon which are placed the residue and coarser portions of the ore already described, and when the stampers are in motion the ore slides down the inclined plane under them, and thus gets crushed. When it is thought the ore has been sufficiently crushed, it is, by means of a current of water running through the mill, carried away through a grating in front of the mill into a channel in which there are two pits, with the result that the more valuable and heavier portion of the ore becomes deposited in the first pit, whilst the inferior portion is carried on, and falls into the second one.

The crushed ore has, however, to undergo other operations before it is considered sufficiently pure for the furnace. That part (the purer portion, called the crop by the Cornish miner) which has deposited in the first pit after removal therefrom, is subjected to a series of further washings, the different apparatus by which these are effected being known in Cornish language as a buddle and a kieve.

“The crop is first subjected to washing in the buddle; this is a wooden trough about 8 feet long, 3 wide, and 2 deep, fixed in the ground with one end somewhat elevated. At the upper end a small stream of water enters, and is reduced to a uniform thin sheet by means of a distributing board, on which a number of small pieces of wood are fastened to break the stream. The ore to be washed is placed in small quantities at a time on a board just below the distributing board, and somewhat more inclined than the body of the buddle, and as the ore is spread out into a thin layer the water carries it forward.

“The richer portions subside near the head of the trough, and the light ores are carried further down. ‘The heads’ are then tossed into the kieve, a covered wooden tub, which is filled with water and ore added by a workman, who keeps the contents of the kieve in continual agitation by turning an agitator, the handle of which projects through the lid of the tub. When the vessel is nearly full the agitation is stopped; the kieve is struck sharply upon the side several times, and its contents are allowed to subside; the upper half of the sediment is again passed through the buddle. Various modifications of the washing process are resorted to, but they are all the same in principle.”[78]

[Footnote 78: Miller.]

The water which has been used in washing the ore on the buddle, as well as that in the kieve, contains in addition to the débris of the gangue more or less of small pieces of the ore itself. Hence this water is not allowed to escape, but conveyed into a narrow channel cut at the end of the buddle, where it deposits the solid materials. These being then removed undergo a second washing on an inclined stage, a process by which any remaining mineral is recovered, followed in Cornwall.

The above is the method of dressing the ores of lead and tin, and, with some modifications, those of copper.

Some metals, as, for example, certain iron and zinc ores, previous to being dressed, require a preliminary exposure for some time to the atmosphere. This operation, which is called ‘weathering,’ has the effect of aiding the subsequent removal by water of certain materials of a clayey, slatey, or marly nature, which sometimes adhere very tenaciously to the ores in question.

Again, in some cases weathering is had recourse to for obtaining a metallic compound in a soluble form. It is by this means that iron pyrites if exposed to the air after a time becomes converted into a sulphate of the metal.

Large quantities of commercial sulphate of iron or green vitriol are manufactured from this natural sulphate after it has been dissolved by the rain, and then crystallised. Sometimes the ores after dressing, and previous to roasting or smelting, are subjected to a process of calcination without access of air, with the object of depriving them of water, carbonic acid and bituminous matters, and also of rendering the ore softer and in a favorable condition to be acted upon by the subsequent metallurgic operations.

The ores having been by these various processes sufficiently freed from extraneous matters, are next, according to their composition, either submitted to the operations of roasting or smelting, and in many cases to both.

_Roasting._ This operation is mostly carried out in a reverbatory furnace. The result of the process upon the ores containing sulphur, which are those chiefly subjected to it, varies with the nature of the ore. Thus, when the sulphides of antimony, arsenic, or zinc are roasted, the sulphur escapes as sulphurous anhydride with the formation of the volatile oxides of arsenic, antimony, or zinc, which sublime, and are afterwards collected and purified with cinnabar or native sulphide of mercury.

Sulphurous anhydride is evolved with the vapours of metallic mercury, these being at the same time condensed by cooling. When copper pyrites (the double sulphide of copper and iron) is placed in the reverbatory furnace, the copper and iron become converted into oxides.

When galena or lead sulphide is exposed to the roasting process, lead oxide and sulphate, with the copious escape of sulphurous acid, are at first formed. The oxide and sulphate become eventually decomposed, leaving behind metallic lead, with a small portion of a subsulphide of the metal. In most cases, however, the effect of roasting on an ore is to convert it into an oxide.

Clay ironstone, which is that from which the greater part of the iron is manufactured in Great Britain, and that known as the black band of the Scotch coal fields, are impure carbonates of iron, and these when roasted yield ferric oxide. The roasting in the case of these minerals is sometimes effected in kilns, but more frequently in the open air; in the latter case by the firing of stacks composed of alternate layers of the ore and of small coal. Calamine or native carbonate of zinc is converted into oxide sometimes by being roasted in kilns, but more frequently in a reverbatory furnace.

_Smelting._ Except in those cases in which the ore is directly reduced from the state of a sulphide to that of a metal, it is, as has been shown, converted into an oxide. If, therefore, it be required to procure the metal _per se_, some method must be adopted for the removal of the oxygen from its oxide.

This process, which is called smelting, and is applied to most metallic oxides, whether of natural or artificial origin, consists in heating the oxide with a substance which has a stronger attraction for oxygen than the metal has. Such bodies are coal, coke, or charcoal, which when raised to very high temperatures in contact with certain metallic oxides, rob them of their oxygen, and thus reduce them to the state of metals, carbonic oxide or carbonic anhydride being at the same time formed and carried off. A mechanical impediment, however, to the reducing action of the fuel upon the ore exists in the rocky, earthy, and other impurities mostly present in large quantities, even after the dressing, which envelop the mineral, and afford it a protective covering. To remove these it is not only necessary that some substance should be added which has the power of combining with them, but of one which is capable of forming a compound which shall become fusible by the heat of the furnace, so that the molten metal as it sinks through it by reason of its greater specific gravity, and falls to the bottom of the furnace, shall be protected in doing so from contact with the air. Many substances, varying with the nature of the gangue accompanying them, are thus employed as fluxes, such as limestone, fluor spar, gypsum, heavy spar, &c., and they act by combining with the silicious compounds contained in the gangue attached to the ore, and forming a fusible silicate known as slag, which is from time to time run off by an aperture at the side of the furnace. Considerable knowledge and experience are required in the selection of suitable fluxes.

The smelting furnaces in which the deoxidation of iron is accomplished are of considerable size. The following description of one, together with the engraving, are from Professor Bloxam’s able work, ‘Chemistry: Inorganic and Organic,’

“Great care is necessary in first lighting the blast furnace, lest the new masonry should be cracked by too sudden a rise of temperature, and when once lighted, the furnace is kept in constant work for years, until in want of repair.

“When the fire has been lighted the furnace is filled up with coke, and as soon as this has burnt down to some distance below the chimney, a layer of the mixture of calcined ore with the requisite quantity of limestone is thrown upon it; over this there is placed another layer of coke, then a second layer of the mixture of ore and flux, and so on in alternate layers, until the furnace has been filled up; when the layers sink down fresh quantities of fuel, ore, and flux are added, so that the furnace is kept constantly full.

“As the air passes from the tuyères pipes into the bottom of the furnace, it parts with its oxygen to the carbon of the fuel, which it converts into carbonic acid, the latter passing the red-hot fuel as it ascends in the furnace is converted into carbonic oxide by combining with an additional quantity of carbon. It is this carbonic oxide which reduces the calcined ore to the metallic state when it comes in contact with it at a red heat, in the upper part of the furnace, for carbonic oxide removes the oxygen at a high temperature from the oxides of iron, and becomes carbonic acid, the iron being left in the metallic state.

“But the iron so reduced remains disseminated through the mass of ore until it has passed down to a part of the furnace which is more strongly heated, where the iron enters into combination with a small proportion of carbon to form cast-iron, which fuses or runs down into the crucible or cavity for its reception at the bottom of the furnace.

“At the same time the clay contained in the ore is acted upon by the lime of the flux, producing a double silicate of alumina and lime, which also falls in the liquid state into the crucible, where it forms a layer of slag above the heavier metal. This slag, which has five or six times the bulk of the iron, is allowed to accumulate in the crucible and to run over its edge down the incline upon which the blast furnace is built; but when a sufficient quantity of cast iron is collected at the bottom of the crucible, it is run out through a hole provided for the purpose, either into channels made in a bed of sand, or into iron moulds, where it is cast into rough semi-cylindrical masses, called pigs, where cast-iron is also spoken of as pig-iron.

“The temperature of the furnace is, of course, highest in the immediate neighbourhood of the tuyères; the reduction of the iron to the metallic state appears to commence at about two thirds of the way down the furnace, the volatile matters of the ore, fuel, and flux being driven off before this point is reached.

“Some idea may be formed of the immense scale upon which the smelting of iron ores is carried out, when it is stated that each furnace consumes in the course of 24 hours about 50 tons of coal, 30 tons of ore, 6 tons of limestone, and 100 tons of air.

“The cast-iron is run off from the crucible once or twice in 12 hours, in quantities of 5 or 6 tons at a time. The average yield of calcined clay-iron stone is 35% of iron.

“The gases escaping from the chimney of the blast furnace are highly inflammable, for they contain, beside the nitrogen of the air blown into the furnace, a considerable quantity of carbonic oxide and some hydrogen, together with the carbonic acid formed by the action of the carbonic oxide upon the ore. Since the carbonic oxide and hydrogen confer considerable heating power upon these gases, they are employed in some iron-works for heating steam-boilers, or for calcining the ore, or for raising the temperature of the blast.

“The composition of the gas issuing from a hot blast furnace (fed with uncoked coal) may be judged of from the following table:——

“_Gas from Blast Furnace._

Nitrogen 55·35 vols. Carbonic oxide 25·97 ” Hydrogen 6·73 ” Carbonic acid 7·77 ” Marsh gas 3·75 ” Olefiant gas 0·43 ” ———————— 100·00 ”

“The carbonic oxide of course renders these gases highly poisonous, and fatal accidents occasionally happen from this cause. Although the bulk of the nitrogen present in the air escapes unchanged from the furnace, it is not improbable that a portion of it contributes to the formation of the cyanide of potassium which is produced in the lower part of the furnace, the potassium being furnished by the ashes of the fuel.” See METALLURGY.

_Assay._ Three general methods are adopted for this purpose:——

1. (MECHANICAL.) This consists in pulverising the ore by any convenient method, and expertly washing a given weight of it (say 1000 gr.) in a wooden bowl or capsule with water, so as to remove the earthy gangues from the denser and valuable metallic matter in such a way that none of the latter may be lost. This is the common plan adopted with auriferous sands, the ores of tin after they have passed the stamping-mill, galena, grey antimony, &c., and may either be employed as an independent process or merely as preparatory to more exact investigations. When galena is thus tested, the product is a nearly pure sulphide of lead, of which every grain is equivalent to ·8666 of metallic lead, the rest being sulphur. The results with grey antimony ore are still more direct, since the product is only melted into pigs before being sent to market. In this state it contains 73% (nearly) of metallic antimony.

2. (HUMID.) Assays in the ‘humid way’ are true chemical analyses, and are described under the head ‘_Estim._’ attached to most of the more important minerals noticed in this work. This plan offers greater facilities and gives more accurate results than either of the other methods.

3. (DRY.) Of the methods of assay in the ‘dry way’ the following are the most accurate, generally useful, and easily applied:——

_a._ (Dr Abiche.) The mineral is reduced to powder, and mixed with 5 or 6 times its weight of carbonate of barium, also in powder; this mixture is fused at a white heat in a platinum crucible, and the resulting slag, after being powdered, is exhausted with hydrochloric acid. This process answers well with both stony and metallic minerals, the most refractory of which give way under this treatment.

_b._ (Liebig.) Into a crucible containing commercial cyanide of potassium, a weighed quantity of the ore, in the state of fine powder, is sprinkled, when the metallic oxides and sulphides which it contains are almost immediately reduced to the metallic state, and may be separated from the scoria by edulcoration with water. With the oxides and sulphides of antimony and tin this reduction occurs at a dull red heat; with the compounds of copper it occurs with the disengagement of light and heat; but an ore of iron requires to be mixed with a little carbonate of potassium or of sodium before throwing it into the fused cyanide, and to be then submitted to a full red heat for a short time, before it is reduced to the reguline state. In this case any manganese present in the ore of iron is left under the form of protoxide. A mixture of about equal parts of dry carbonate of sodium and cyanide of potassium answers better for the crucible than the cyanide alone. See ALLOYS, METALLURGY, &c.; also PERCY’S METALLURGY.

=ORGAN′IC BA′SES.= These interesting bodies may be divided into two classes: the first comprising those which occur ready formed in nature (ALKALOIDS); and the second those produced by artificial processes in the laboratory (ARTIFICIAL ALKALOIDS, ARTIFICIAL ORGANIC BASES). They all contain the element NITROGEN. The natural bases have already been described under ALKALOID. Hitherto they have none of them been produced by artificial means. The bases of artificial origin are mostly volatile, and their constitution is much simpler than that of the native bases. Of the vast number which have been formed the following are, perhaps, the most interesting:——ETHYLAMINE, METHYLAMINE, AMYLAMINE, ANILINE, NAPHTHYLAMINE, CHINOLINE, and PICOLINE. These and other bodies of the class are noticed under their respective heads.

By Berzelius the natural organic bases (owing to the invariable presence in them of hydrogen and nitrogen) were regarded as compound ammonias, or combinators of ammonia with a variety of neutral principles.

He conceived the greater part of these neutral bodies were incapable of isolation, and further more that the closest union existed between them and the ammonia. Thus it was his opinion that quinine C_{20}H_{12}NO_{2}, 3HO (halving the modern formula) was a compound of the group C_{20}H_{9}O_{2} with oxide of ammonium and water of crystallisation thus (C_{20}H_{9}O_{2}H_{4}NO)_{2}HO. He believed the organic base owed its basicity to the ammonia. Berzelius’ opinion carried weight at the time, from the circumstance that certain neutral substances when directly combined with ammonia were capable of forming a number of artificial bases very similar in qualities and also in composition to the natural ones, or those obtained from living plants. Thus, the artificial base _thiosinamine_ having the formula C_{4}H_{5}NS is produced by the combination of oil of mustard and ammonia; and another base may be artificially obtained from the union of oil of bitter almonds with ammonia.

Liebig, who was one of the first chemists to dispute the correctness of Berzelius’ hypothesis, by showing that the natural organic bases never gave any indication of the presence in them of ready formed ammonia, replaced it by the suggestion that they might be bodies into the composition of which amidogen (H_{2}N) entered, and that these, instead of being compounds of ammonia and an organic group, might be derivatives from ammonia; or ammonia in which an atom of hydrogen had been displaced by an equivalent organic radicle.

The labours of subsequent chemists, notably those of Messrs Wurtz and Hofman, have developed Liebig’s theory, and have proved the analogy in structural arrangement between ammonia and the greater number of organic bases; whilst they have further shown, not only in one, as supposed by Liebig, but for all three of the hydrogen atoms in ammonia, may be substituted certain compound radicles.

=ORGAN′IC SUBSTANCES.= We have reserved a notice of the method of estimating the quantity of carbon, hydrogen, oxygen, and nitrogen, in organic compounds, until now, in order to present them to the reader in a more useful and connected form. The operation essentially consists, in respect of the first three, in causing the complete combustion of a known quantity of the substance under examination, in such a manner that the carbonic acid and water thus produced shall be collected, and their quantity determined. From these the proportions of their elements are easily calculated. The estimation of the quantity of nitrogen (as is also the case with chlorine, phosphorus, sulphur, &c.) requires a separate operation. The two great classes of organic bodies (azotised and non-azotised) are readily distinguished from each other by heating a small portion with some solid hydrate of potassium, in a test tube. If nitrogen is present, it is converted into ammonia, which may be recognised by its characteristic odour and its alkaline reaction.

1. _Estimation of the_ CARBON, HYDROGEN, _and_ OXYGEN.——_a._ The method of Prof. Liebig, now almost exclusively adapted for this purpose, is as follows:——The substance under examination, reduced to powder, is rendered as dry as possible, either by the heat of a water bath or by exposure over concentrated sulphuric acid, _in vacuo_; 5 or 6 gr. of it are then weighed in a narrow open test tube, 2 or 3 inches long, and to ensure accuracy this tube and any little adhering matter is again weighed after its contents have been removed——the difference between the two weights being regarded as the true quantity of the substance employed in the experiment. A ‘combustion tube,’ of hard white Bohemian glass (·4 to ·5 inch diam.; 14 to 18 inches long), is next taken, and about 2-3rds filled with black oxide of copper, prepared by the ignition of the nitrate, and which has been just re-heated to expel hygrometric moisture. Nearly the whole of this oxide, whilst still warm, is then gradually poured from the tube and triturated with the organic sample in a dry and warm mortar, after which the mixture is transferred to the combustion tube, and the mortar being rinsed out with a little fresh oxide, which is added to the rest, the tube is, lastly, nearly filled with some warm oxide fresh from the crucible. The contents of the tube are next arranged in a proper position by a few gentle blows, so as to leave a small passage for the evolved gases from the one end of the tube to the other. (See _engr_.)

The ‘combustion tube’ with its ‘charge’ is next placed in a ‘furnace’ or ‘chauffer’ of thin sheet iron (see middle figure _above_). Its open end is then connected with a ‘drying tube’ filled with fragments of fused chloride of calcium, and carefully weighed. This tube is, in its turn, connected with a small glass (‘Liebig’s potash bulbs’) containing solution of pure potassa of sp. gr. 1·27, also carefully weighed. The junction with the first is made by means of a perforated cork; that with the second by means of a small tube of india rubber tied with silk, the whole being made quite air-tight. The apparatus is then tested by sucking a few bubbles through the liquid with the dry lips, when, if the level of the solution of potassa in the two legs continues unequal for some minutes, the joints are regarded as perfect. The whole arrangement being complete (see _engr._), burning charcoal is now placed in the furnace around the front part of the combustion tube, and when this has become red-hot the screen is slowly moved back, and more burning charcoal is added, until the furthest extremity of the tube has been exposed to its action. (Gas, burned in furnaces specially contrived for the purpose, is now usually employed instead of charcoal.) The firing is so regulated that the gas enters the potassa apparatus in bubbles easily counted, without any violence or inconvenience, and it is kept up as long as gas is extricated. As soon as the apparatus is complete, and the slightest retrograde action is observed, the charcoal is removed from the combustion tube, and the extreme point of this last is broken off. A little air is then sucked through the apparatus in order to seize on any remaining carbonic-acid gas and moisture. The potash apparatus and the chloride of calcium tube are, lastly, detached, and again accurately weighed. The increase in the weight of the first gives the weight of the carbonic acid formed during the combustion; that of the second the weight of the water. The numbers equivalent to any given number of grains, found as above, are converted into the proportions per cent. by simply dividing them by the weight of the organic substance which has been employed in the experiment, and moving the decimal point of the result two figures to the right.

Gr. Gr. 1 gr. of _Carbonic acid_ = 0·27273 of _Carbon_ + 0·72727 of _Oxygen_, 1 ” _Water_ = 0·11112 ” _Hydrogen_ + 0·88888 ” —— ———————— ———————— 2 less 0·38385 equal to 1·61615 ” —— ———————— ————————

_b._ In applying the preceding method to volatile liquids, it is necessary to enclose them in a small bulb with a narrow neck, instead of mixing them directly with the protoxide of copper. The bulb with its contents is introduced into the combustion tube, and after some 6 or 8 inches of the protoxide is heated to redness, a hot coal is applied near where the bulb is situated, so that the liquid which it contains may be slowly volatilised and passed through the heated mass in the state of vapour, and be thus completely burned. For further information, consult Fresenius’ ‘Chemical Analysis.’

2. _Estimation of the_ NITROGEN——_a._ Several methods are employed for this purpose, but the only one of general application, and adapted to the non-scientific operator, is that of MM. Varrentrap and Will, described under GUANO. To ensure correct results, the caustic soda must be pure, and the lime of good quality and well burnt. The last, having been properly slaked with a little water, holding the former in solution, the mixture is thoroughly dried in an iron vessel, and then heated to full redness in an earthen crucible. The ignited mass is rubbed to powder in a warm dry mortar, and either used at once or carefully preserved from the air. The best quantity of the organic substance to operate on is, in this case, about 10 gr., which must be dried, and accurately weighed with the usual precautions. Bodies very rich in either nitrogen or hydrogen are best mixed with about an equal weight of pure sugar before triturating them with the soda-lime. MM. Varrentrap and Will weigh the nitrogen under the form of double chloride of platinum and ammonium, dried at 212° Fahr. This salt contains 6·272% of nitrogen.

_b._ M. Péligot has modified the preceding plan by conducting the gaseous matter extricated during the operation into a three-bulb tube charged with a standard solution of sulphuric acid. This he subsequently pours into a beaker-glass, and after tinging it with a single drop of tincture of litmus, he tests it with either a standard aqueous solution of soda or one of lime in sweetened water, after the common method of alkalimetry. The difference between the saturating power of the acid in its normal condition and after its exposure in the condenser indicates the amount of ammonia formed. (See GUANO.) Each grain of ammonia contains ·82353 gr. of nitrogen.

_Concluding Remarks._ The successful application of the above processes requires considerable care and some aptitude in manipulating, as well as the employment of a very delicate balance for determining the weights. A greater error in the weighings than the 1/250 gr. cannot be tolerated when exact results are desired. The method of MM. Varrentrap and Will for the determination of nitrogen answers admirably for all organic compounds containing it, except those in which it exists under the form of hyponitrous, nitrous, and nitric acids; for which, however, it is not required. When extreme accuracy is aimed at, the atmospheric air in the apparatus, and that absorbed during the preliminary operations by the substances employed, must be expelled before the application of heat to the combustion tube. (See WATER, ANALYSIS OF.)

=OR-MOLU′.= [Fr.] This name is given to gold-coloured brass or bronze, so finished off as to have the appearance of gold, or of being gilt; but it is often applied in a more general sense. The French more particularly excel in working in or-molu, and the products of this branch of their industry hold an important position in the art manufactures of France.

To give or-molu its richest appearance, “it is not unfrequently brightened up after ‘dipping’ (that is, cleaning in acid) by means of a scratch-brush (a brush made of very fine brass wire), the action of which helps to produce a very brilliant gold-like surface. It is protected from tarnish by the application of lacquer.” (Ure.)

Ure says or-molu contains more copper and less zinc than ordinary brass, and that although, in many of its applications, the colour is heightened by means of a gold lacquer, in some cases the true colour of the alloy is best preserved after it has been properly developed by means of dilute sulphuric acid.

=ORMSKIRK MEDICINE.= A nostrum supposed to prevent hydrophobia, so named after the residence of its inventor, Mr Hill, of Ormskirk. It is said to have consisted of the ingredients named below, but nothing certain is known on the subject, as the inventor died without revealing its secret:——Chalk, 1/2 oz.; Armenian bole, 3 dr.; elecampane root, 1 dr.; alum, 10 gr.; oil of aniseed, 5 or 6 drops; all in fine powder. For a dose, to be taken for 6 successive mornings, in a glass of weak milk and water.

=OR′PIMENT.= Native yellow sulphide of arsenic. The finest samples used by artists (golden orpiment) come from Persia. See ARSENIC (Tersulphuret).

=OR′RIS.= _Syn_. ORRIS ROOT, FLORENTINE R.; RADIX IRIDIS, L. The dried rhizome of _Iris Florentina_, _pallida_, and _Germanica_. Sialogogue, irritant, subacrid, and errhine. Chiefly employed to impart a violet odour to oils, tooth powder, snuffs, spirits, &c.; and when cut into peas to keep open issues.

=ORSE′DEW.= Dutch leaf-gold.

=ORSEL′LIC ACID.= Two compounds pass under this name——ALPHA-ORSELLIC ACID and BETA-ORSELLIC ACID. They closely resemble each other, and are obtained in a similar manner; the first from the South American variety of _Rocella tinctoria_, the last from that grown at the Cape.

=ORSELLIN′IC ACID.= _Syn_. LECANORIC ACID. A compound formed along with picroerythrine, by boiling erythric acid for some time with water. It is also formed by boiling alpha-orsellic acid with water. In both cases, if the ebullition is too long continued, the new acid is wholly or in part converted into orcin.

_Prop., &c._ Crystallisable; bitter-tasted; soluble in water; its aqueous solution, by exposure to the air, assumes a beautiful purple colour.

=ORTHOCLASE.= _Syn._ POTASSIUM FELSPAR. This material, which is a double silicate of potassium and aluminium, enters into the composition of many rocks, and is a common ingredient in granite. It has the following composition:——Silica, 64·8 parts; alumina, 18·4 parts; and potash, 16·8 parts. Part of the potassium is frequently replaced by small quantities of calcium, magnesium, and sodium.

Orthoclase is used for glazing the finest varieties of porcelain, a very intense heat being necessary to effect its fusion in the porcelain furnace. By the Chinese potters it is called _petuntze_. “The name ‘orthoclase’ is generally restricted to the subtranslucent varieties, there being many subvarieties (founded on variations of lustre, colour, and other differences), of which the following are some of the principal, viz. _adularia_, a transparent or translucent felspar, met with in granitic rocks (frequently in large crystals); _moonstone_; _sunstone_; _Murchisonite_, _erythrite_; glassy felspar or _lanadine_, a transparent variety found in volcanic rocks, containing 4 per cent. of soda or upwards.”[79]

[Footnote 79: Ure.]

=ORTHOPÆ′DIA.= In _surgery_, the straightening, correcting, or curing deformities of children. See SURGERY.

=OSIER.= The osier, which is a species of willow (_salix_), and is largely used in the construction of baskets and other wickerwork, is extensively cultivated at Nottingham and on the level lands of Cambridgeshire and Huntingdonshire, as well as on the banks of the Thames, Severn, and other rivers. The small islands in these rivers, when planted with osiers, are known as osier HOLTS. But large as is the supply of shoots afforded by the English osier beds, it is insufficient for home consumption; hence great quantities of ozier rods are imported into this country from Holland, Belgium, and France. There are a great variety of oziers, and it is found that those which have been the most highly cultivated yield the toughest and finest wood, and those best adapted for the superior kinds of basket work. The branches of the wilder and less domesticated kind, which are more liable to break, are used for making hoops and coarse baskets. This last variety, which is known as the COMMON OSIER (_Salix viminalis_), grows on the alluvial grounds of Britain, and in other European countries, and is often planted on the banks of rivers to prevent their being washed away.

The following are the principal varieties of osier indigenous to this country, and which yield the most valuable wood:——1. THE FINE BASKET OSIER (_Salix Forbyana_). 2. THE GREEN-LEAVED OSIER, or ORNARD (_Salix rubra_). 3. THE SPANISH ROD (_Salix triandra_). 4. THE GOLDEN OSIER, or GOLDEN WILLOW (_Salix vitellina_).

The osier requires plenty of water, and hence it thrives best in those localities and low grounds which are washed by a river. The soil best adapted for it is a rich but not clayey one. In planting an osier bed an important condition is that the trees should be placed sufficiently closely together, since it is found that, with too much space, the shoots do not develop into long and slender branches, which are so much sought after. The shoots are cut once a year, at any time between the fall of the leaf and the rising of the sap in spring. After being cut they are divided into those destined for brown, and those for white baskets. In the latter ease the rods have to be peeled, but as this operation cannot be performed at once, and the rimous of the bark would be difficult were they allowed to dry, the shoots are placed upright and sustained in that position in wide shallow trenches in about four inches of water, where they are kept until they begin to bud and blossom in the spring, which they do as if they were attached to the parent plant. The peeling is easily done by passing them through an instrument known as a _break_. If the spring has been a cold one, they have, previous to peeling, to be laid for some time under a layer of litter.

When they have been peeled they are stacked, preparatory to being sold. With the rods intended for brown baskets, no peeling is of course necessary. They are therefore carefully stacked in some place protected from the rain, and diligently watched to see that no heat is set up in them, as is sometimes the case with freshly stacked hay, and which, if not stacked, would cause the rods to rot and render them useless.

In England, besides the native produce, 5000 tons of osiers are annually imported, valued at about £40,000. Of late years the Australian colonists have turned their attention to the cultivation of the osier, in the hopes of supplying the demand for it in Great Britain.

=OS′MAZOME.= The substance on which the peculiar odour and flavour of boiled meat and broth were formerly supposed to depend.

_Prep._ From lean meat, minced, and digested in cold water, with occasional pressure; the filtered infusion is gently evaporated nearly to dryness, and then treated with alcohol; the alcoholic tincture is, lastly, evaporated. The product has a brownish-yellow colour, is soluble in water, and its aqueous solution is precipitated by infusion of galls and the mineral astringent salts.

=OS′MIUM.= Os. A rare metal found associated with the ores of platinum by M. Tennant, in 1803.

These ores mostly consist of a mixture of platinum, palladium, rhodium, osmium, ruthenium and iridium. When they are treated with aqua regia, the insoluble residue which remains, chiefly consists of an alloy and osmium, iridium, ruthenium and rhodium. To separate the osmium from the other metals, Fremy takes advantage of its easy oxidability, and of the volatility of its tetroxide.

In the first part of this process (which is a great improvement upon the methods previously followed) the above residue or alloy is heated to redness in a platinum or porcelain tube. In that part of the tube which projects from the furnace, some fragments of porcelain are placed, and the tube is connected with a series of glass flasks, in which the tetroxide of osmium is condensed as it distils over, any tetroxide that may have escaped condensation is retained by a solution of caustic potash, placed in the last flask of the series. This last flask is connected with an aspirator, by means of which a current of air is drawn through the apparatus.

Before being allowed to enter the heated tube the air is dried by being made to pass through tubes filled with pumice-stone, moistened with sulphuric acid. During the operation the osmium and ruthenium become oxidised, the tetroxide of osmium condenses in needles in the flasks, and mechanically carries forward the deoxide of ruthenium, which is deposited upon the pieces of porcelain.

There are several processes for obtaining osmium in the metallic condition. We give two of the most simple of these. 1. By treating the volatile tetroxide of osmium obtained by Fremy’s method, as above described, with hydrochloric acid and metallic mercury in a closed vessel at 140° C.

The mercurous oxide which is first formed at the expense of the oxygen contained in the tetroxide of osmium is decomposed by the hydrochloric acid, and calomel is produced, together with metallic osmium.

The water and excess of acid are removed by evaporation to dryness, and on heating the residue in a small porcelain retort, the excess of mercury and calomel is drawn off, pure osmium being left behind in the form of a fine powder.

2. Deville and Debray procure it in the metallic form by passing the tetroxide of osmium, in a current of nitrogen, over carbon which has been obtained by passing the vapour of benzine through a porcelain tube at a high temperature. The metal procured by this process is of a fine blue colour, with a tinge of grey.

The specific gravity of osmium in the pulverulent form is about 10; but after having been heated to the fusing point of rhodium in the oxyhydrogen jet, it acquires a density of 21·4, and in the crystalline state it has a sp. gr. of 22·477. Osmium appears to be the least fusible of all the metals.

There are five known oxides of osmium:

=1. Osmium protoxide.= (OsO). The anhydrous protoxide is of a greyish-black colour. It is insoluble in acids. Its bluish-black hydrate, which dissolves in hydrochloric acid, forms a solution of osmium dichloride of a deep indigo blue colour. The solution absorbs oxygen readily, and becomes converted into the tetrachloride (OsCl_{4}).

=2. Osmium sesquioxide.= (Os_{2}O_{3}.) This has never been isolated. Its salts, which are uncrystallisable, are of a rose-red colour.

=3. Osmium dioxide.= (OsO_{2}.) This is black.

=4. Osmium trioxide.= (OsO_{3}.) This possesses feebly acid properties. It has never been obtained in a separate form; with potassium it forms a crystalline, sparingly soluble compound, having the composition K_{2}OsO_{4}, 2H_{2}O, a dipotassic osmite.

=5. Osmium tetroxide.= _Syn._ OSMIC ACID (OsO_{4}). This oxide may be obtained by operating, according to Fremy’s process, on the ores of platinum, as already described. It is also formed when metallic osmium is heated with potassic nitrate, or roasted in air. It crystallises in colourless, transparent, flexible needles, which fuse easily, and dissolve readily in water. Its aqueous solution, however, does not redden litmus. Tetroxide of osmium is converted into vapour at about 100°C. The fumes are excessively irritating and deleterious, and have an odour somewhat like that of chlorine. This oxide unites with alkalies, but not with acids. It is given off as tetroxide when the alkaline solution which contains it is boiled. If applied to the skin, this oxide becomes partially reduced, and imparts a permanent black colour to the skin, due to the deposition of metallic osmium. With tincture of galls its solutions give a distinctive blue precipitate.

There are four chlorides of osmium, the best known of which are the dichloride and the tetrachloride.

1. =Osmium dichloride.= (OsCl_{2}). _Syn._ OSMIOUS DICHLORIDE, OSMIUM PROTOCHLORIDE. This is green, and sublimes in green needles. It may be obtained by heating metallic osmium in a current of dry chlorine gas. It forms double salts, which are of a green colour.

2. =Osmium tetrachloride.= (OsCl_{4}). _Syn._ OSMIC TETRACHLORIDE, OSMIUM BICHLORIDE. This may be procured in the same manner as the dichloride, using, however, an excess of chlorine. It occurs as a red, crystalline, fusible, deliquescent powder. It is more volatile than the dichloride. Both the dry chloride and the tetrachloride of osmium are dissolved by water, which decomposes them into tetroxide of osmium, hydrochloric acid and the metal.

=OSTEOCOL′LA.= A rough sort of glue or gelatin obtained from bones by digestion in dilute hydrochloric acid, to remove their earthy matter, and afterwards acting on the residuum with water at a high temperature, until it is wholly dissolved.

=OTAL′GIA.= Pain in the ear. See EARACHE.

=O′′THYL.= In chemistry, a radicle having the formula C_{2}H_{3}O, assumed by Professor Williamson to exist in acetic acid.

=OT′TO OF ROSES.= See OILS (Volatile).

=OVALBU′MEN.= White of egg; to distinguish it from seralbumen, or the albumen of the serum of the blood.

=O′VENS.= A very ingenious and useful improvement in the apparatus for baking was introduced some years ago by Mr Sclater, of Carlisle. It consists in causing the articles to be baked to traverse a heated earthenware tube. This tube forms the oven. It is of considerable length, and the biscuits or other articles are slowly traversed through it, from end to end, at such a rate as will allow of the baking being completed during the passage. The biscuits are carried on trays, set on travelling chains; or the trays are made into an endless web or chain. The oven is thus entirely self-acting, and the articles demand no attention whatever from the attendants, whilst the system combines superior economy with the best results. A ‘pyrometer,’ or heat indicator, is attached externally, so that the attendant can regulate the heat with great facility. The object of these improvements is to reduce the cost of baking, and to improve the appearance of the baked articles. The apparatus is applicable as well to the baking of articles of clay or earthenware as to bread or biscuits.

Of the ovens now in common use by the bakers, that known as the ‘hot-water oven’ is perhaps the best; not merely in reference to economy, but also with reference to its superior cleanliness, and the ease with which the articles operated on may be turned out of that delicate yellowish-brown tint for which the bread of the Viennese and Parisian bakers is so celebrated. See BAKING, BREAD, &c.

=OWNER.= For the purposes of the Public Health Act this term is thus defined:——“‘Owner’ means the person for the time being receiving the rack-rent of the lands or premises in connection with which the word is used, whether on his own account, or as agent or trustee for any other person, or who would so receive the same if such lands or premises were let at a rack-rent.”

=OX.= The _Bos Taurus_ (Linn.), one of the ruminantia. In its more limited sense the word is restricted to the emasculated animal. The flesh, milk, skin, horns, bones, and blood of this animal are all serviceable to man. Goldbeater’s skin is prepared from the peritoneal membrane of its cæcum. Its blood, fat, horns, and excrement were among the simples of the Ph. L. 1618. See BEEF, GALL, MILK, and _below_.

=Ox-Gall.= Syn. OX-BILE; FEL BOVINUM, F. BOVIS, F. TAURI, L. Crude ox-gall is noticed at page 774. Refined ox-gall (_Fel bovinum purificatum_) is prepared as under:——

1. Fresh ox-gall is allowed to repose for 12 or 15 hours, after which the clear portion is decanted, and evaporated to the consistence of a thick syrup by the heat of a water bath; it is then spread thinly on a dish, and exposed in a warm situation near the fire, or to a current of dry air, until nearly dry; it is, lastly, put into wide-mouthed bottles or pots, and carefully tied over with bladder. In this state it will keep for years in a cool situation. For use a little is dissolved in water.

2. Fresh gall, 1 pint; boil, skim, add powdered alum, 1 oz.; boil again till the alum is dissolved, and when sufficiently cool pour it into a bottle, and loosely cork it down. In a similar manner boil and skim another pint of gall, add to it 1 oz. of common salt, and again boil, cool, and bottle it, as above. In three months decant the clear from both bottles, and mix them in equal quantities; the clear portion must then be separated from the coagulum by subsidence or filtration.

_Uses, &c._ Both the above are employed by artists to fix chalk and pencil drawings before tinting them, and to remove the greasiness from ivory, tracing paper, &c. The first is also used in medicine.

=OX′ALATE.= _Syn._ OXALAS, L. A salt of oxalic acid. The soluble oxalates are easily formed by directly neutralising a solution of oxalic acid with a metallic hydrate, carbonate, or oxide; and the insoluble oxalates, by double decomposition. See OXALIC ACID and the respective bases.

=OXAL′IC ACID.= H_{2}C_{2}O_{4}. _Syn._ ACIDUM OXALICUM, L. This substance was discovered by Bergman in 1776. It occurs both in the mineral and organic kingdoms, and is produced artificially by the action of nitric acid on sugar, starch, woody fibre, &c. It abounds in wood-sorrel, in which it exists in combination with a little potassa. With the exception of gum and sugar of milk all starchy and saccharine substances yield oxalic acid when treated with nitric acid at a somewhat elevated temperature.

_Prep._ 1. From sugar:——

_a._ Nitric acid (sp. gr. 1·42), 5 parts, diluted with water, 10 parts, is poured on sugar, 1 part, and the mixture is digested at a gentle heat as long as gaseous products are evolved; the liquid is then concentrated by evaporation until it deposits crystals on cooling; the crystals, after being drained and freed from superfluous moisture, are redissolved in the smallest possible quantity of boiling water, and the solution is set aside to crystallise. The residuary ‘mother-water’ is treated with a little fresh nitric acid (say 1-1/2 part) at a gentle heat, after which it is evaporated, as before, for a second crop of crystals. This process is repeated until the solution is exhausted. The brownish-coloured crystals thus obtained are allowed to effloresce by exposure to dry air, and are then redissolved and recrystallised. By repeating this treatment they yield pure colourless oxalic acid at the third crystallisation.

_b._ (Schlesinger.) Sugar (dried at 257° Fahr.), 4 parts, and nitric acid (sp. gr. 1·38), 33 parts, are digested together, as before, and as soon as the evolution of gas ceases the liquid is boiled down to one sixth of its original volume, and set aside to crystallise. The whole process may be completed in about 2 hours, and in 1 vessel, and yields of beautifully crystallised oxalic acid, at the first crystallisation, a quantity equal to 56 to 60% of the weight of the sugar employed.

_c._ (Ure.) Nitric acid (sp. gr. 1·4), 4 parts, and sugar 1 part, are digested together by the heat of a water bath, and as soon as gas ceases to be extricated the vessel is removed from the heat, and set aside to cool and crystallise. The use of a little sulphuric acid along with the nitric acid contributes to increase the product.

2. From POTATO- or DEXTRIN-SUGAR:——(Nyren.) From the washed pulp of potatoes, boiled for some hours with water, q. s., in a leaden vessel, with about 2% of oil of vitriol, until the fecula of the pulp is converted into saccharine matter, shown by the liquid being no longer turned blue by iodine; the whole is then filtered through horse-hair bags or strainers, and the filtrate is evaporated until its density is such that a gallon of it weighs 14 to 14-1/2 lbs.; in this state it is converted into oxalic acid by treatment with nitric acid in the way already described. A similar process was patented some years ago by Messrs Davy, Macmurdo, and Co.

3. From SAWDUST:——(Roberts, Dale, & Co. Patent.) This process is the one now usually employed for the manufacture of oxalic acid on the large scale. It is based on Gay-Lussac’s discovery, that wood and similar substances are converted into oxalic acid by fusion with caustic alkali. The practical details of the process are thus given by Dr Murray Thomson, of Edinburgh:——(1) Hydrate of sodium and hydrate of potassium, mixed in the proportion of 2 equivalents of the former to 1 equivalent of the latter, are dissolved, and solution evaporated until of specific gravity 1·35; sawdust is now stirred in until a thick paste results. (2) This paste is then heated on iron plates, during which it is constantly stirred; water is first given off; the mass then swells; inflammable gases, hydrogen and carburetted hydrogen, are evolved, along with a peculiar aromatic odour. When the temperature has been maintained at 400° for one or two hours, this stage of the process is complete; the mass has now a dark colour, and contains only 1 to 4 per cent. of oxalic acid, and about ·5 per cent. of formic acid. The bulk, therefore, of the mass at this stage consists of a substance whose nature is not yet known, but which is intermediate between the cellulose and oxalic acid. (3) The next stage consists in a simple extension of the last, in which the mass is heated till quite dry, care being taken that no charring takes place. It now contains the maximum quantity of oxalic acid, 28 to 30 per cent. (4.) This oxalic acid now exists as oxalate of potassium and sodium in the grey powder resulting from stage 3. This powder is now washed on a filter with solution of carbonate of sodium, which seems to have the singular and unexpected power of decomposing the oxalate of potassium and converting it into oxalate of sodium. At all events, it is quite true that all traces of potassa are washed out with the solution of carbonate of sodium. The only explanation that occurs to account for this unusual decomposition is that oxalate of sodium is a more insoluble salt than oxalate of potassium, and therefore may be formed by preference. (5) This oxalate of sodium is now decomposed by boiling milk of lime. Oxalate of calcium falls as a precipitate, and soda remains in solution. This soda is boiled down, and again made use of with fresh sawdust. This recovery of alkali is also practised with the potassium salt which filters through in the last stage. (6) The oxalate of calcium is now decomposed in leaden vessels with sulphuric acid. Sulphate of calcium is precipitated, and oxalic acid is in solution, which is now evaporated, and the acid separates in crystals, which now need only to be recrystallised to make them quite pure, and fit the acid for all the purposes for which it is employed. _Prod._ By this ingenious process 2 lbs. of sawdust are made to yield 1 lb. of oxalic acid.

_Prop., &c._ Colourless, transparent, prismatic crystals, possessing a powerful sour taste and acid reaction; these effloresce in warm dry air, with loss of 28% (2 eq.) of water, and then form a white powder, which may be sublimed in part, without decomposition; the crystals are soluble in 8 parts of water (9 parts, “and form a solution of sp. gr. 1·045,”——Ure) at 60° Fahr., in their own weight or less of boiling water, and in about 4 parts of alcohol; with the acids, it forms salts called oxalates.

_Tests._——1. Solution of chloride of barium occasions a white precipitate in neutral solutions of oxalic acid (oxalates), which is soluble in both nitric and hydrochloric acid.——2. Solution of nitrate of silver, under like circumstances, gives a white precipitate, which is soluble in nitric acid, and in ammonia, and which, when heated to redness, yields pure silver.——3. Lime water and solutions of all the soluble salts of calcium produce white precipitates, even in highly dilute solutions of oxalic acid or of the oxalates, which is freely soluble in both nitric and hydrochloric acid, but is nearly insoluble in either acetic or oxalic acid, and is converted into carbonate of calcium upon ignition.——4. Oxalic acid (or an oxalate), when heated, in the dry state, with oil of vitriol in excess, is converted into carbonate anhydride and carbonic oxide; the former produces a white precipitate with lime water, and the latter, when kindled, burns with a faint blue flame. Of the above tests, solution of sulphate of calcium (_vide_ No. 3) is the most delicate and characteristic.——5. It is distinguished from Epsom salt by its acid reaction, its solubility in rectified spirit, its complete dissipation by heat, and by emitting a slight crackling noise during its solution in water. See MAGNESIA (Sulphate).

_Uses, Pois., &c._ Oxalic acid is chiefly used in the arts of calico printing and bleaching; to remove ink-spots and iron moulds from linen, and to clean boot-tops. It is extremely poisonous. The treatment, in cases of its having been swallowed, is to promote vomiting, and to administer chalk, whiting, or magnesia, mixed up with water, in considerable quantities. The use of the alkalies or their carbonates must be avoided, as the compounds which these form with oxalic acid are nearly as poisonous as the acid itself. The remaining treatment is noticed under ACIDS. In poisoning by oxalic acid the nervous system is almost always affected, and the patients experience numbness, formication of the extremities, and sometimes convulsions, so that the symptoms somewhat approach those produced by strychnia, from which it is distinguished by its corrosive action on the tissues, and its effect upon the heart and circulatory system.

_Concluding Remarks._ The manufacture of oxalic acid is an important one. The process of Roberts, Dale, and Co. has so much cheapened the price of oxalic acid, that in 1851 it sold for 16d. per lb., and in 1864 it only cost from 8d. to 9d. per lb. More than half the amount of oxalic acid used all over the world is now made from sawdust. In manufacturing the acid from sugar, on the large scale, the first part of the process is either conducted in salt-glazed stoneware pipkins of the capacity of 3 to 5 quarts each (which are about two thirds filled and set in a water bath), or in wooden troughs lined with lead, and heated by means of a coil of steam-pipe. On the small scale, a glass retort or capsule is commonly employed. The most appropriate temperature appears to be about 125° Fahr. and the best evidence of the satisfactory progress of the decomposition is the free but not violent evolution of gas, without the appearance of dense red fumes, or, at all events, any marked quantity of them. When these are disengaged with violence and rapidity, a greater quantity of the newly formed acid suffers decomposition, and flies off in a gaseous form. The sp. gr. of the nitric acid commonly used on the large scale ranges from 1·22 to 1·27 equivalent quantities being taken. The evaporation is preferably conducted by the heat of steam. The evolved nitrous vapours are usually allowed to escape, but this loss may be in part avoided by conveying them into a chamber filled with cold damp air, and containing a little water, when they will absorb oxygen, and be recondensed into fuming nitric acid. Various modifications of this plan have been patented. That of Messrs McDougall and Rawson, which is one of the simplest and best, consists in passing the mixed nitrous fumes through a series of vessels containing water, and connected together by tubes, so that the fumes which collect at the top of one vessel are conveyed to nearly the bottom of the next one, and then, bubbling up through the water, mix with the air, a supply of which is provided for the purpose. The nitrous fumes are thus brought alternately into contact with air and water, and by the time they reach the last vessel are reconverted into nitric acid. Another plan is to pass the mixed nitrous vapours through a vessel stuffed with some porous substance, as pumice-stone or pounded glass, conjointly with a supply of steam from a boiler and a supply of oxygen by a blowing machine.

The product obtained by skilful manipulation are——from good dry sugar, 128%; from good treacle, 107%.——“One cwt. of good treacle will yield about 116 lbs. of marketable oxalic acid, and the same weight of good brown sugar may be calculated to produce about 140 lbs. of acid.” “As a general rule, 5 cwt. of saltpetre, or an equivalent of nitrate of soda, with 2-1/2 cwt. of sulphuric acid, will generate sufficient nitric acid to decompose 1 cwt. of good sugar, and yield, as above, 140 lbs. of fair marketable oxalic acid, free from superfluous moisture.” (Ure.) On the small scale, 5 parts of sugar yield nearly 6 parts of crystallised acid.

Chemically pure oxalic acid is best prepared by precipitating a solution of binoxalate of potassium with a solution of acetate of lead, washing the precipitate with water, decomposing it, whilst still moist, with dilute sulphuric acid or sulphuretted hydrogen, and gently evaporating the filtrate so that crystals may form as it cools.

=OXALURIA.= Also known as the oxalic-acid diathesis; is an abnormal condition of the system, marked by the presence in the urine of crystals of oxalate of lime. The crystals occur as minute transparent octahedra, and sometimes in the form of dumb-bells. They can be easily recognised under a microscope with a power of from 200 to 250 diameters, when they present a very beautiful appearance. They differ from phosphatic deposits in being insoluble in acetic acid. Their presence is mostly indicated by the appearance in the urine of a cloud of mucus, which forms after the urine has stood some little time.

Oxaluria most generally affects persons of dyspeptic and sedentary habits and of nervous temperament; those suffering from skin affections and neuralgia are also occasionally attacked by it. In ordinary cases the treatment consists in the administration of the nitro-hydrochloric acid, in infusion of gentian two or three times a day, or of a course of quinine and iron, aided by plenty of exercise in the open air, care being taken to avoid fatigue. If it can be borne the shower bath should also be had recourse to. Rhubarb tarts and tomatoes, which contain oxalic acid, must be excluded from the diet; so also should aerated water and too much sugar.

If after a short time the oxalates should not disappear from the urine under this treatment, the patient should seek proper medical advice; since the persistent presence of this deposit is of very serious significance, as indicating the existence in the bladder of that dangerous form of urinary concretion known as ‘mulberry calculus.’

=OXIDA′TION.= _Syn._ OXYDATION. The combination of bodies with oxygen, forming oxides; the operation or process adopted to induce or facilitate such conversion.

=OX′IDE.= _Syn._ OXYD; OXYDUM, L. A compound formed by the union of oxygen with another body.

=OXYCHLO′′RIDE.= _Syn._ OXICHLORIDE; OXYCHLORIDUM, L. A term often loosely applied to compounds of an oxide and chloride, whether in definite or variable proportions. See ANTIMONY (Oxychloride), &c.

=OX′YCRATE.= _Syn._ OXYCRATUM, L. The old name of a mixture of vinegar and water, dulcified with honey.

=OXYCRO′CEUM.= See PLASTERS.

=OX′YGEN.= O. _Syn._ OXYGEN GAS, DEPHLOGISTICATED AIR†, EMPYREAL A., VITAL A.†; OXYGENIUM, L. An elementary body discovered by Scheele and Priestly in 1774. It is remarkable that, although this substance forms a large proportion of our atmosphere (nearly one fourth), and confers upon it the power of supporting respiration and combustion, and also constitutes the principal portion of the water of our rivers and seas (eight ninths), and enters largely into the composition of the majority of the various mineral bodies that form the bulk of our globe, its existence should have remained unsuspected, or at least undetermined, until a comparatively recent date. Oxygen is an essential constituent of all living organisms. It is absorbed by animals during respiration, and evolved in a free state by growing vegetables when exposed to sunlight. The oxygen gas of the atmosphere is mechanically mixed, not chemically combined, with the nitrogen.

_Prep._ 1. From red oxide of mercury, heated over a spirit lamp or a few pieces of ignited charcoal. The operation is usually performed in a small green-glass retort, or in a short tube of hard Bohemian glass, closed with a perforated cork furnished with a piece of bent glass tube of small bore, to convey the liberated gas to the vessel arranged to receive it. Pure. 1 oz. yields about 100 cubic inches.

2. From chlorate of potassium, as the last. Pure. 100 gr. yield nearly 100 cubic inches (Brande; 115——Ure). This is the plan adopted in the P. Cod. The decomposition occurs with both the above substances at a heat below that of redness.

3. From a mixture of chlorate of potassium (in coarse powder), 3 parts; powdered binoxide of manganese, 1 part; both by volume. Pure. 100 gr. of the mixture yield about 110 cubic inches as oxygen. This method, which has received the approval of Faraday, is exceedingly convenient. The gas is evolved with a rapidity which is entirely at the command of the operator by simply increasing or lessening the heat. The residuum in the retort may be kept for another operation, if not exhausted; or it may be at once washed out with a little warm water, and the manganese, which is uninjured by the process, reserved for future use. Red lead, black oxide of copper, red oxide of iron, and several other substances, answers nearly as well as binoxide of manganese.

4. From a mixture of bichromate of potassium, 3 parts; oil of vitriol, 4 parts; gently heated, as before. Yields pure oxygen very freely, and with a rapidity entirely at the will of the operator. (Balmain.)

5. From binoxide of manganese and oil of vitriol, equal parts; as the last. 44 gr. of pure binoxide of manganese yield 8 gr., or 24 cubic inches, of oxygen; 1 oz. yields 88 gr., or 256 cubic inches. (Liebig.)

6. (On the large scale.)——_a._ From nitre exposed to a dull red heat in an iron retort, or gun-barrel. 1 lb. yields about 1200 cubic inches of gas, contaminated, more or less, with nitrogen. (Ure.)

_b._ From binoxide of manganese, as the last. 1 oz. of the pure binoxide yields 44 gr., or 128 cubic inches, of oxygen (Liebig); 1 lb. of good commercial binoxide yields from 1500 to 1600 cubic inches, or from 5 to 6 galls.

_c._ M. Boussingault has reinvestigated a process, long known, although not usefully applied, by which pure oxygen gas may be obtained from the atmosphere at a trifling cost, so as to enable it to be collected in unlimited quantities and preserved in gasometers, like coal-gas, for application in the arts, manufactures, and sanitation. This process depends upon a peculiar property possessed by the earth baryta, of absorbing atmospheric oxygen at one temperature and evolving it at another; or rather, the ready conversion of hydrate of barium into peroxide of barium by a current of atmospheric air at a dull red heat, and the decomposition of this peroxide, by steam, at a lower temperature, even at 212° Fahr., with reproduction of hydrate of barium, the process being in reality a continuous one. The baryta is mixed with a portion of hydrate of calcium or of magnesium, and the mixture being placed in an appropriate earthen tube heated to dull redness, is oxidised by passing a current of dry atmospheric air over it. As soon as the oxidation is complete, the tube is connected with the gas-holder, and a jet of steam allowed to act upon it; this reconverts the peroxide of barium into hydrate of barium, the excess of oxygen being given off and collected in the gas-holder. The baryta is then again oxidised by a fresh current of air and deoxidized by steam, and the whole process is repeated as frequently as required. One ton of baryta, thus treated, is capable of yielding 2500 cubic feet of pure oxygen every 24 hours; and this, as it does not waste or lose its properties, at the mere cost of the fuel and labour required in the process.

_d._ From ferrate of potassium, prepared on the large scale. When exposed to moisture or thrown into water, pure oxygen is evolved. This method has been successfully adopted to maintain the air of diving-bells, and of other confined spaces, in a state fit for respiration.

_e._ The decomposition of sulphuric acid has been recommended by MM. Deville and Debray as a means whereby large quantities of oxygen gas may be obtained at a low price. Into a tubulated retort are put fragments of fire brick, and upon these, when raised to a full red heat, sulphuric acid is made to fall drop by drop, by passing through an iron tube, which passes through and is luted to the tubulure. The tube reaches to the bottom of the retort, and the acid is poured into it through a bent funnel. The sulphuric acid becomes decomposed into sulphurous anhydride, oxygen, and water. The volatilised products are sent through a spiral condenser, by which the water and any undecomposed acid become liquefied; whilst the sulphurous acid is removed by subsequent washing with water, and oxygen is collected in the usual manner.

_f._ A process for obtaining oxygen on a large scale, and which has been made the subject of a patent in this country, has been devised by MM. Marechal and Tessié du Mothay. It consists in heating in a current of steam the manganates, permanganates, chromates and ferrates of the alkalies and alkaline earths, and regenerating the residue by passing air over it at a red heat.

_g._ Mallet procures oxygen in large quantities as follows:——He puts into retorts revolving on horizontal axes, a mixture of cuprous chloride, and kaolin or sand. He moistens this with water, heats it to 100° C., and passes air through the retorts for some hours. His oxygen he obtains from heating the resulting cupric oxychloride to about 400° C.; the aqua residual cuprous chloride becomes converted into oxychloride on cooling 100 kilograms of cuprous chloride, after conversion into oxychloride, about 3 cubic mètres of oxygen.

7. OXYGEN GAS AT THE ORDINARY TEMPERATURE. Boettger states that when a mixture is made of equal weights of the peroxides of lead and barium, and dilute HNO_{3} of a strength of 9° Baumé is poured thereon, a current of pure O, free from ozone and antozone, is given off abundantly. This mixture of the two peroxides may be kept dry in a stoppered bottle for any length of time. Boettger also prepares pure oxygen, free from ozone, by submitting permanganate of potassium to a gentle heat.

8. Fleitman[80] has found that when chloride of lime in solution is heated with a small quantity of freshly prepared peroxide of cobalt, it is completely resolved into chloride of calcium and oxygen. A concentrated solution consisting of 35 per cent. of chloride of lime, which must be previously filtered to prevent frothing, yields when heated with 1/10th to 1 per cent. of peroxide of cobalt, a volume of oxygen from 25 to 30 times as great as that of the liquid, and always rather more than the calculated quantity, probably in consequence of the absorption of oxygen from the air. The remaining peroxide may always be employed again. A like result follows if, instead of the peroxide, an ordinary salt of cobalt in small quantity be used. Fleitman seeks to explain the reaction on the supposition that there are several peroxides of cobalt, and that the effects produced depend upon the alternate formation and partial reduction of a higher oxide; or on the formation of a cobaltic and a percobaltic hypochlorite, which is subsequently decomposed into cobaltous chloride and oxygen.

[Footnote 80: Watts.]

_Prop._ Oxygen gas is colourless, tasteless, inodorous, and incombustible; the sp. gr. is 1·057 (Dumas; 1·1026——Berzelius & Dulong; 1·111——Thomson); 100 cubic inches at 60° Fahr., and 36 inches of the barometer, weigh 34·29 gr. (Dumas; 34·109 gr.——Berz.; 34·6 gr.——Brande; 33·85 gr.——Ure). Its density to that of atmospheric air is, therefore, as about 11 to 10. It is a powerful supporter of combustion, and its presence is essential to the existence of both animal and vegetable life. It forms 21% (20·81%) by volume, and 23% by weight, of the atmosphere. (M. Dumas.) Water dissolves about 5 per cent. by volume of oxygen, and by pressure a much larger quantity, forming oxygenated water (AQUA OXYGENII). Oxygen has recently been liquified.

_Tests._ 1. It is distinguished from other gases by yielding nothing but pure water when mixed with twice its volume of hydrogen and exploded, or when a jet of hydrogen is burnt in it.——2. A recently extinguished taper, with the wick still red hot, instantly inflames when plunged into this gas.——3. A small spiral piece of iron wire ignited at the point, and suddenly plunged into a jar of oxygen, burns with great brilliancy and rapidity. Charcoal does the same.

_Estim._ The estimation of the quantity of oxygen in an organic compound has already been described. For determining the quantity present in atmospheric air, and other like gaseous mixtures, Dobereiner has proposed the use of pyrogallic acid. The air under examination (freed from moisture) is measured into an accurately graduated tube over mercury, capable of holding about 30 cubic centimètres, and which it should 2/3rds fill. A solution formed of 1 part of dry hydrate of potassium and 2 parts of water, and in volume about 1/35th that of the air, is next introduced by means of a pipette with a curved point, and is gently agitated therewith in the gas for a short time; the decrease of volume gives the proportion of carbonic anhydride present. A solution of pyrogallic acid (1 gramme in 5 or 6 centimètres of water), equal in volume to one half that of the solution of potassa already used, is then introduced by means of another pipette, and the mixed liquids are cautiously shaken together over the inner surface of the tube. When absorption ceases (which it does in a few minutes), the quantity of residual gas (nitrogen) is read off from the graduations; the difference in volume before and after the introduction of the pyrogallic acid indicates the proportion of oxygen. This is a mere modification of Prof. Liebig’s method. 1 gramme of pyrogallic acid in combination with hydrate of potassium is capable of absorbing about 189 cubic centimètres of oxygen. (Dobereiner.) Other methods employed for the analysis of air, depending on the increase or loss of weight when the air is passed over finely divided copper heated to redness, the loss of volume when the air is exploded in a eudiometer with half its bulk of hydrogen, or when a stick of phosphorus is left in it for some hours, are well known, and described at length in every elementary work on chemical analysis. The last method, although less accurate than the others, has the advantage of extreme simplicity.

_Uses._ Oxygen has been employed to increase the illuminative and heating power of lamps, and to render vitiated air respirable, &c.; and when largely diluted with atmospheric air, or condensed in water, as a remedial agent in asphyxia arising from the inhalation of carbonic acid and carbonic oxide.

Dr Ringer says that if oxygen be administered as a gaseous bath for an hour or two at a time, and the bath repeated six or eight times a day, it is of great service in senile gangrene.

_Concluding Remarks._ Oxygen gas may be collected in the usual way, either over water, mercury, or in bags; or, on the large scale, in gasometers. The purity of the products of the several processes given above depends on the substances from which the gas is obtained being themselves pure. For particular experiments the first portion of gas should be allowed to escape, or be received apart, as with this, as with the other gases, it is contaminated with the atmospheric air of the apparatus. The gas procured from manganese or nitre may be purified by passing it through milk of lime or a solution of caustic potash; it will still, however, retain some traces of nitrogen. M. Limousin[81] has devised an apparatus for the preparation of oxygen by the attendants of hospitals, which obviates the risk of bursting of the retorts, attending its preparation by the old method. The apparatus consists of two cast-iron hemispheres, whose edges, which are well polished and about two centimètres thick, can be fitted hermetically upon each other, and fastened by three screws. The mixture of chlorate of potash and peroxide of manganese is placed in the lower hemisphere, which rests upon a tripod; the upper hemisphere, from which projects an iron tube, is now screwed on, and the iron tube connected with india-rubber and glass tubing with a Wolf’s wash-bottle, from which the gas after being washed passes through a second glass tube, and is thus ready for use. It may be conducted into an air-tight bag, in which it will keep for several weeks. Such a bag when supplied with a tube and stop-cock will afford a ready means for inhalations. Oxygen in a condensed or compressed state is prepared by Mr Orchard, High Street, Kensington. See ORGANIC SUBSTANCES, OZONE, GASES, LIQUEFACTION OF, &c.

[Footnote 81: ‘Pharm. Centralhalle,’ xiv, 318.]

=OXYGENA′TION.= _Syn._ The act or process of combining with oxygen. Formerly it was of more general application than the word ‘oxidation,’ with which it has been regarded as synonymous. ‘Oxygenation’ is, however, at the present day practically obsolete.

=OXYGENI′SED LARD.= _Syn._ OXYGENATED AXUNGE; AXUNGIA OXYGENATA, L. _Prep._ (Ph. Bat. 1805.) From prepared lard, 16 parts, melted over a slow fire, and then mixed with nitric acid, 1 part; the combination being promoted by constant stirring with a glass rod, until it ceases to affect litmus paper. It should be extremely white, and should be kept in the dark. See OINTMENT OF NITRIC ACID.

=OXYHYDROGEN BLOWPIPE.= See BLOWPIPE. Deville and Debray (‘Ann. Ch. Phys.’ [3], lvi, 385) employ the oxyhydrogen blowpipe in the following manner for effecting the fusion of platinum and the refractory metals which accompany it. The apparatus consists of the blowpipe _C_ (see _below_), a furnace _ABD_, and a crucible _GHI_. The blowpipe is composed of a copper tube about half an inch in diameter, terminating below in a slightly conical platinum jet about 1-1/2 inch long. Within this tube, which is supplied with hydrogen or coal-gas through the stop-cock _H_, is a second copper tube _C′_ for supplying oxygen, terminated also by a platinum nozzle with an aperture of about a twelfth of an inch in diameter.

The furnace _ABD_ consists of three pieces of well-burnt lime of slightly hydraulic quality, which may be turned at a lathe with ease. The cylinder _A_ is about 2-1/2 inches thick, and is perforated by a slightly conical hole into which the blowpipe fits accurately, passing about half-way through the thickness of the mass. A second somewhat deeper cylinder of lime, _B_, is hollowed into a chamber wide enough to admit the crucible, and leave an interval of not more than a sixth of an inch clear around it. _KK_ are four apertures for the escape of the products of combustion.

The outer crucible _HH_ is also made of lime, but it contains a smaller crucible _I_ of gas coke, provided with a cover of the same material; and in this the substance to be used is placed, the crucible resting on the lime support _D′_. The conical cover _G_ is made of lime, and its apex should be placed exactly under the blowpipe jet, at a distance from it of 3/4 to 1-1/2 inch.

The different pieces of the furnace must be bound round with iron wire to support them when they crack. The oxygen is admitted under a pressure of a column of 16 inches of water. The temperature is gradually raised to the maximum, and in about eight minutes from this time the operation is complete.

By employing a jet of mixed coal-gas and oxygen (_EQ_, see _engr._) in a furnace of lime, Deville and Debray succeeded, at an expense of about 43 cubic feet of oxygen, in melting and refining, in 42 minutes, 25·4 lbs. avoirdupois of platinum, and casting it into an ingot in a mould of gas coke; and much larger masses have since been melted by this method. Lime is so bad a conductor of heat that if a cup of lime not more than 0·8 inch thick be filled with melted platinum the exterior scarcely rises beyond 300° Fahr. (Miller’s ‘Elements of Chemistry,’ 3rd. ed., pt. ii, p. 825.)

=OX′YMEL.= _Syn._ OXYMEL, L. An acidulous syrup made of honey and vinegar. There are only two oxymels in the last Ph. L. The ingredients in an oxymel should be of such a character, and in such proportions, as to produce a mixture of the proper consistence without evaporation.

=Oxymel of Col′chicum.= _Syn._ OXYMEL COLCHICI CORMI, OXYMEL COLCHICI, L. _Prep._ (Ph. D. 1826.) Fresh corms (roots) of meadow saffron, 1 oz.; distilled vinegar, 1 pint (wine measure); macerate for 2 days, press out the liquor, filter, add of clarified honey, 2 lbs., and boil down the mixture to the consistence of a syrup, frequently stirring.——_Dose_, 1 to 3 dr., twice or thrice a day; in gout, rheumatism, dropsy, &c.

=Oxymel of Gar′lic.= _Syn._ OXYMEL ALII, L. _Prep._ (Ph. L. 1746.) Sliced garlic, 1-1/2 oz.; caraway seed and sweet fennel seed, of each 2 dr.; boiling vinegar, 8 fl. oz.; infuse, strain, and add of clarified honey, 10 oz. In hooping-cough, chronic diarrhœa, rheumatism, &c.

=Oxymel of Narcissus.= (Van Mons.) _Syn._ OXYMEL NARCISSI. _Prep._ Vinegar of Narcissus (made with 1 part of fresh flowers of daffodil to 8 of vinegar), 1 part; honey, 4 parts. Dissolve.——_Dose._ A teaspoonful. In hooping-cough and spasmodic asthma.

=Oxymel, Pec′toral.= _Syn._ OXYMEL PECTORALE, O. INULÆ COMPOSITUM, L. _Prep._ (Ph. Br.) Elecampane, 1 oz.; orris root, 1/2 oz.; water, 1-1/2 pint; boil to 1/2 pint, strain, add of honey, 16 oz.; ammoniacum, 1 oz.; (dissolved in) vinegar, 3 fl. oz.; lastly, boil to an oxymel.——_Dose_, 1 spoonful, occasionally; in coughs, humid asthma, &c.

=Oxymel, Sim′ple.= _Syn._ VINEGAR SYRUP, ACETATED HONEY; OXYMEL (Ph. L. & D.), OXYMEL SIMPLEX, MEL ACETATUM, L. _Prep._ 1. (Ph. L.) Acetic acid (sp. gr. 1·048) 7 fl. oz.; distilled water, 8 fl. oz.; mix, and add them to honey, 5 lbs., previously made hot. This contains only one half the acid ordered in the Ph. L. 1836.

2. (Ph. D.) Clarified honey, 1 lb.; acetic acid (sp. gr. 1·044), 3 oz.; as before. Stronger than the last.

3. (Ph. L. 1836.) Honey, 10 lbs.; acetic acid (1·048), 1-1/2 pint; as before. This contains too much vinegar. (See No. 1.)

4. (Wholesale.) From honey (thick and good), 12 lbs.; melt it by a gentle heat, add of distilled vinegar (of fully 5%), 2 quarts, and strain the mixture through flannel. No evaporation is required.

_Uses, &c._ Demulcent and refrigerant.——_Dose_, 1 to 4 fl. dr., either gradually sucked from the spoon or dissolved through some simple liquid. Dissolved in water, it forms a useful and pleasant cooling drink or gargle in fevers, sore throats, hoarseness, &c.; but in some individuals it occasions griping. It is commonly used as an adjunct, in mixtures, &c.

=Oxymel of Squills.= _Syn._ HONEY OF SQUILLS; OXYMEL SCILLÆ (B. P.), MEL SCILLÆ (Ph. L.), O. SCILLITICUM (L.) _Prep._ 1. (B. P.) Mix and evaporate on a water bath vinegar of squills, 1 pint, and clarified honey, 2 lbs., till the product when cold has a specific gravity of 1·32.

2. Vinegar of squills, 2-1/2 pints; gently evaporate it to 12 fl. oz., and add of honey (previously made hot), 5 lbs.

3. (Ph. L. 1836.) Strained honey, 3 lbs.; vinegar of squills, 1-1/2 pint; boil to a proper consistence. The formula of the Ph. D. 1826 was similar.

_Uses, &c._ Expectorant, and in large doses nauseant.——_Dose_, 1/2 to fl. 2 dr.; in chronic coughs, hoarseness, humeral asthma, &c.

=Oxymel of Ver′digris.= See LINIMENT OF VERDIGRIS.

=OXYR′RHODYNE.= _Syn._ OXYRRHODINON. An old compound formed of 1 part of vinegar of roses and 2 parts of oil of roses.

=OXYSAC′CHARUM.= A syrup acidulated with vinegar. See SYRUP.

=OXYSUL′PHIDE.= A name given to certain compounds or mixtures of metallic oxides and sulphides. See ANTIMONY, OXYSULPHIDE, &c.

=OYS′TER.= _Syn._ OSTREA, L. This well-known shell-fish is the _Ostrea edulis_ (Linn.)

“The oyster is a genus of lamellibranchiate molluscs of the section with a single adductor muscle. The shell consists of two unequal and somewhat irregularly-shaped valves of laminated and closely foliated structure, and the hinge is without tooth or ridge, the valves being held together by a ligament lodged in a little cavity in each. The animal is in its organisation among the lowest and simplest of lamellibranchiate molluscs. It has no foot, and, except when very young, no power of locomotion, or organ of any kind adapted to that purpose. Its food consists of animalcules, and also of minute vegetable particles, brought to it by the water, a continual current of which is directed towards the mouth by the action of the gills. The gills are seen in four rows when the valves of the shell are separated, a little within the fringed edge of the mantle. In the most central part is the adductor muscle; and between the adductor muscle and the liver is the heart, which may be recognised by the brown colour of its auricle. The mouth——for, as in the other lamellibranchiata, there is no head——is situated beneath a kind of hood formed by the union of the two edges of the mantle near the hinge. It is jawless and toothless. The ovaries are very large during the season of reproduction, which extends over certain months when oysters are out of season for the table. Oysters are hermaphrodite.”[82]

[Footnote 82: Chambers’ ‘Encyclopædia.’]

The fecundity of the oyster is amazing. Leeuwenhoek estimated that an oyster, when full of spawn, contained from 3000 to 4000 of its offspring, and it has also been computed that one oyster alone produces nearly a million and a quarter of eggs. The eggs are hatched and the young produced within the shell and mantle of the parent, where they continue floating or swimming about in the vicinity of the gills in a creamy-looking kind of mucus or fluid until expelled. Their expulsion is preceded by a change of appearance in the fluid to a brownish or muddy colour; a circumstance that may possibly indicate an alteration of composition in the liquid unfavorable to the infant oyster, and thus lead to its departure. Their departure or expulsion from all the parent molluscs of the oyster-bank or bed takes place at the same time.

When they leave the parent shell the young oysters, which in this condition are called _spat_, are not more than 1/120th of an inch in length; and two millions of them when closely packed do not occupy a space of more than a cubic inch. Thus cast adrift they are carried away by currents, their multitudinous numbers being considerably diminished by their falling a prey to numerous fish, as well as from their frequent inability to find a suitable resting-place. This obtained, the young oyster or spat attaches itself to it, and makes it the permanent home on which it eats, grows, and breeds, and, debarred of locomotion, passes its existence unless, of course, removed by external causes. Pending its obtaining a suitable locality the young oyster is provided with a powerful swimming apparatus which, it has been surmised, becomes absorbed or otherwise disappears when its function is rendered unnecessary by the stationary life of the oyster after it has secured a habitat.

The objects to which it attaches itself are numerous. The _Ostrea parasitica_, a species of oyster found in warm climates, fixes itself to the roots and branches of trees growing within reach of and washed by the tide. Again, in some of the southern states of North America, large oyster-beds, which are sometimes of such magnitude as to form buttresses against the force of the tides and winds, originate from the habit of young oysters attaching themselves to the shells of old ones. Similarly the banks of some of the rivers of Georgia, which run up some few miles inland from the sea, are composed of masses of living oysters attached to each other. These banks, which are so massive as to make a channel for the river, are known as _racoon banks_, because this animal is one amongst others which frequents them for the sake of devouring the oysters.... In some of the French _parcs_, or artificial oyster-beds, the young oysters attach themselves to large unglazed tiles, or to faggots or other solid bodies which are placed in suitable situations for the purpose; in the English artificial beds hurdles are frequently employed, upon which the spat become deposited. It appears the young oysters select dark objects, such as slate or black stones, in preference to bodies of a lighter colour to fix themselves to, and that they choose, where practicable, the inner side of the object, or that portion of it away from the light. After a time the young oysters are removed from the breeding beds, placed in the fattening beds, from whence they are removed when they have attained a sufficient size, and sent upon the market. In England oysters are not regarded as fit to be eaten until they are at least three years old; whereas in France they are served up to table about a year earlier. The chief enemy of the young oyster is a species of whelk, known in France as the _bigourneau_, _dog whelk_, or _piercer_. These creatures, which are found in immense quantities in the celebrated oyster-beds at Arcachon, near Bordeaux, cause great destruction amongst the bivalves. Part of their anatomy consists of a boring apparatus, with which they pierce the shell of the oyster; whatever of the dead oyster is left by the whelk is devoured by the crabs, which creep into the aperture in the shell made by the former.

We have already alluded to the abundance of oysters in parts of Georgia, where, we may add, they are not only confined to the alluvial shores of the rivers, but are also found in large numbers amongst the long grass of the adjoining low lands.

In these districts it is by no means an uncommon practice for the inhabitants to improvise a meal by picking up a bunch of oysters and roasting them over a fire kindled on the spot. In many of these localities the oysters occur in quantities so immense that a vessel of 100 tons might be loaded within three times her own length.[83]

[Footnote 83: Chambers’ ‘Encyclopædia.’]

There are also many other parts of America in which the yield of the oyster-beds is enormous. In the State of Maryland 6000 persons are said to be employed dredging, and nearly 11,000,000 bushels of oysters were taken in 1870-71.

In Baltimore as many as 10,000 persons are employed in tinning this bivalve. Comparing the plenteousness of the oyster in America with its great scarcity of late years in our country, and the consequent much lower price of the foreign bivalve, we should be prepared to learn that considerable supplies of oysters, both alive and preserved in tins, come to us from America. The bulk of those consumed in Britain are a small variety, and come from Maryland and Virginia.

In 1872, owing to the diminished yield of the English oyster-beds, an attempt was made to introduce the American oyster into British waters; and we believe the depôt for this purpose still exists at Cleesethorpes, at the mouth of the Humber, where operations in this branch of oyster culture are being carried on by the Conway Company. If, however, the opinion of an eminent pisciculturist be correct, viz. that the American oyster will not breed in our waters, we should conceive the experiment will be abandoned, since nothing will be gained by relaying them, that cannot be attained by simply importing them and sending them to the market, since it is asserted they are kept alive out of water for a month.

A few years back a Select Committee appointed by Parliament to inquire into the causes of the scarcity of oysters issued in 1876 a report in which, endorsing the opinion of previous authorities on oyster culture, they attributed the diminished yield of our oyster-beds to continual over-dredging for them in open waters, without allowing sufficient ‘close time.’ The Committee found that, in France, where the stringent observances of the ‘close season’ was enforced, the supply of oysters had increased concurrently. The Committee, therefore, recommended the establishment ‘of a general close time,’ extending from May 1st to September 1st, subject to certain exceptions under the supervision of the Board of Trade; the levying of penalties for buying or selling oysters for consumption during the ‘close season’ being also recommended. The Committee further recommended that no oysters should be sold from the deep-sea fisheries under 2-1/2 or 3 inches in diameter. Commenting upon the above report, ‘Nature’ very sensibly remarks:——“What is really wanted for the protection of the oyster is the assurance that these animals shall not be sold before they have a chance of reproducing their kind. Since the introduction of the railway system, the demand for oysters in distant places has become so great and the price has risen so high, that oyster culturists are tempted to send immature animals to market, and it is this fact, more than any failure of spat, that is leading to the scarcity. There are not, in consequence of the unceasing demand and consequent high price, so many full-grown oysters left to spat as there ought to be; hence the scarcity. Any Act of Parliament that decrees two oysters to grow where only one grew before will be greedily welcomed both by oyster culturists and by the public, and we hope that the issue of the present Report will lead to some effective measures being taken for the preservation of this delicious creature ere it be too late.” Previous to 1846 the wholesale price of best English natives was £2 2s. a bushel; since then the price has risen rapidly to £4 4s. in 1865, in 1866 to £5, and in 1869 it had advanced to £8; that is, they had risen nearly 300 per cent. in 8 years, which is equivalent to an advance of from 1/2d. to 2d. each. At the present time they are, we believe, sold at from 3s. to 3s. 6d. a dozen by the retail dealer.

Oysters are nutritious and easy of digestion when fresh, but are apt to prove laxative to those unaccustomed to their use. It is generally believed that they are in season each month of the year the name of which contains the letter R. Whitstable in Kent, and Colchester and other places in Essex, are the great nurseries or feeding-grounds for supplying the metropolis, and, indeed, the whole of England, with the most esteemed variety (NATIVES) of this shell-fish. The shells (TESTÆ PREPARATÆ, T. OSTREARIÆ) were formerly used in medicine as an absorbent.

Of the various species of oysters, that which holds the foremost place in the estimation of the _gourmet_ is the ‘English native,’ now, alas! owing to the unwise rapacity of the collector, nearly dredged out of existence.

The native has a historic reputation too, since it appears it was eagerly sought after by the old Romans, and was a frequent dish at their tables. The enthusiasm of the celebrated Dr Kitchener for this particular oyster was very intense. He is very particular in directing its shell to be opened with the greatest care so that it may be eaten alive and “_tickled to death by the teeth_.”

The green oyster of Ostend is also prized by epicures; it acquires its colour from its food, which consists chiefly of green monads and confervaæ. Some of the American oysters are excellent in flavour, and are said to be without the copper taste occasionally to be met with in English oysters. They smack a little of the mussel.

Payen gives the following as the composition of the oyster:——

Mean of two Analyses.

Nitrogenous matter 14·010 Fatty matter 1·515 Saline matter 2·695 Non-nitrogenous matter and loss 1·395 Water 80·385 —————— 100·00

See SHELL FISH, SAUCES, &c.

=Oyster, Scalloped.= Put them with crums of bread, pepper, salt, nutmeg, and a bit of butter, into scallop shells or saucers, and bake them before the fire in a Dutch oven.

=Oysters, Fried= (to garnish boiled fish). Make a batter of flour, milk and eggs, add a little seasoning to it; dip the oysters into it, and fry them a fine yellow brown. A little nutmeg should be put into the seasoning, and a few crumbs of bread into the flour.

=Oysters, Stewed.= Open them, and separate the liquor from them, then free them from grit by washing, strain the liquor, and add it to the oysters with a small piece of mace and lemon peel, and a few white peppercorns. Simmer very gently, and add some cream and a little flour and butter. Let them be served with sippets.

=Oysters, To Feed.= Pat them into water, and wash them with a birch broom till quite clean. Then place them bottom downwards in an earthenware pan; sprinkle them with flour, oatmeal, and salt, and then cover with water. Repeat this treatment every day, taking care to make the water pretty salt.

=OZOKERIT.= _Syn._ FOSSIL WAX, MINERAL WAX. This substance, which has within the last few years been utilised as a source of paraffin and the mineral hydrocarbon oils, is found in various localities in the tertiary strata, mostly occurring in, or in close proximity to, the coal measures. But although extensive deposits of it are to be met with in Gallicia and on the slopes of the Carpathian mountains, it is by no means an abundant body. In the Austrian empire there are many large manufactories for its conversion into paraffin and the mineral oils. In our country there is we believe only one, that of Messrs Field. Ozokerit is usually met with as a brown and compact substance, occasionally yellow; however, it is sometimes black. It melts at a temperature varying from 60° to 80° C.

NEFT-GIL is a substance very similar to ozokerit, and is formed on the island of Swätoi-Ostrow in the Caspian Sea. According to Rossmässler, neft-gil is treated in the following manner:——15 cwt. of the crude material is put into iron stills provided with a leaden worm, and submitted to fractional distillation, yielding 68 per cent. of distillate, consisting of 8 per cent. of oil, and 60 per cent. of crude paraffin. The oil thus obtained is yellow, opalescent, possesses an ethereal odour, and a sp. gr. of 0·75 to 0·81. Each distillation yields a quantity of a light oil boiling below 100° C., which is used for the purpose of purifying the paraffin. The crude paraffin obtained by the first distillation is tolerably pure, has a yellow colour, and can at once be treated by the hydraulic press and centrifugal machine; the oil from these operations is again submitted to fractional distillation in order to obtain more paraffin. The pressed paraffin is melted and treated at 170° to 180° C. with sulphuric acid, which is next neutralised by means of lime, and the paraffin again rapidly distilled, then again submitted to strong pressure, and the material obtained treated with 25 per cent. of the light oil; then again melted, again pressed, and finally treated with steam for the purpose of eliminating the last trace of essential oil. The material obtained by this treatment is a perfectly pure, colourless material, free from smell, transparent, and so hard as to exhibit in large blocks almost a metallic sound. The fusing point is 63° C.

=OZONE= (Greek, όζωh, I smell) is a peculiar variety of oxygen, characterised by its greater weight, its peculiar chlorous smell, its intensely active oxidising powers, and, finally, by the ease with which it passes into common oxygen. The history of ozone may be summed up as follows:——In 1785 Van Marum observed the production of a peculiar smell when electric sparks were passed through oxygen. This smell, which every one who has worked with an electric machine must have noticed, Van Marum regarded as the “smell of electricity,” thinking that electricity was a substance. In 1840 Schönbein, of Basle, proved the existence of a definite substance, to which he assigned the name of ozone, and discovered several modes of producing it, a delicate test for it, and several of its most striking properties. He subsequently added many new facts, but to the time of his death he never held a correct theory in regard to its nature. Later researches by Marignac and Dedalline, Becquerel and Fremy, Andrews and Tait, Soret, Brodie, and others, have established the true nature of this remarkable body. It is now generally admitted that it only differs from common oxygen in containing three atoms of oxygen in each molecule instead of two. In fact, as the formula for oxygen is O_{2}, that of ozone is O_{3}. It follows that ozone is half as heavy again as oxygen, and it has accordingly been demonstrated that its specific gravity is 24 (H = 1), that of oxygen being 16. All the known reactions of ozone are easily explained in accordance with this view.

Ozone may be generated in several ways. 1. By the action of electricity on oxygen or air, sparks are far less efficacious than the silent or ‘slow’ discharge; but the best apparatus is the induction-tube of Siemens. This consists of two tubes, one inside the other. The inner side of the inner and the outer side of the outer tube are coated with tinfoil, and these coatings are connected with the terminals of a powerful induction-coil. Dry air or oxygen streams between the tubes and passes out, strongly charged with ozone.

2. M. Boillot has proposed a modification of Siemens’ apparatus, which consists of two glass tubes, one fitting within the other, and each coated externally with powdered coke made to adhere by means of gelatin. The coatings of the two tubes are connected with the poles of an induction coil, and a stream of oxygen is made to pass between the tubes, and becomes thus exposed to the influence of the silent discharge, as in Siemens’ contrivance.

3. Hozeau has invented an apparatus which he calls an ‘ozoniser,’ by means of which ozone is produced in considerable quantities. In an ordinary straight gas-delivery tube is placed a wire of copper, lead, or, better, platinum, 4 to 6 décimètres long, with one of its extremities passing through the side of the upper portion of the tube. On the exterior of the tube is coiled a similar wire over the path of the preceding. When the two are placed in communication with a Ruhmkorff’s coil, giving a 2 or 3 centimètre spark, a slow stream of oxygen passing through the tube will be strongly charged with ozone. By this apparatus Hozeau has prepared oxygen containing 60 to 120 (once 188) milligrams of ozone per litre. Electrolysis of water furnished only 3 to 5 milligrams, barium peroxide and sulphuric acid 10 milligrams per litre.[84]

[Footnote 84: ‘Comptes Rendus’ (‘Watt’s Dictionary,’ second supplement), lxx, 1286.]

4. During certain processes of oxidation a piece of phosphorus, half covered with water in a bottle of air, absorbs a portion of the oxygen, while another portion becomes partially ozonised.

5. By plunging a clean glass rod heated to about 260° C. into a jar containing a few drops of ether.

6. By mixing very gradually 3 parts of strong sulphuric acid and 2 of permanganate of potash.

7. It has been shown that ozone is formed in small quantity during the burning of hydrogen at a jet, and in several analogous reactions.

8. During the liberation of oxygen at low temperatures, when barium dioxide is moistened with sulphuric acid, the odour of ozone is at once apparent, and the evolution proceeds for a considerable time.

9. In the electrolysis of water the oxygen evolved consists partly of ozone, especially if the poles are small.

10. Linder has suggested an easy method for the production of ozone for hygienic purposes, which is as follows:——Make a mixture of manganese peroxide, potassium permanganate, and oxalic acid. Two spoonfuls of this powder, if placed on a dish and gradually mixed with water, will generate ozone sufficient for a room of medium size; more water is added in small portions from time to time as the evolution ceases; the powder may be kept in a bottle ready for use.

Ozone has never been isolated. By the use of Siemens’ apparatus, oxygen containing, as a maximum, twenty volumes per cent. of ozone may be obtained. This represents a contraction of about 1-11th during formation. But it is at present impossible to separate the one from the other. Ozone is entirely converted into oxygen by a temperature of 270° C. The conversion is effected more slowly at lower temperatures. Silver, iron, copper, when moistened, are oxidised on the surface immediately at ordinary temperatures by ozone.

Silver even becomes converted into a peroxide, although it will not combine with ordinary oxygen, either when moist or dry. Little or no absorption of ozone takes place when the metals are perfectly dry, except with dry mercury and dry iodine, both of which remove it immediately. It was conclusively shown by Andrews and Tait that little or no contraction followed the absorption of ozone by these or any other agents. Hence, as suggested by these observers, it seems probable that the ozone is resolved into a quantity of ordinary oxygen equal in bulk to itself, which is liberated at the moment when another portion of its oxygen enters into combination with the metal or the iodine.

Ozonised air becomes deozonised when passed over cold manganese dioxide, silver dioxide, or lead dioxide. When ozone is mixed with peroxide of hydrogen, water and oxygen are formed. In these cases the ozone is converted into ordinary oxygen, and the peroxides into monoxides.

=Antozone=, which Schönbein surmised to be oxygen in an oppositely electrified condition to ozone, has been shown with great probability by Van Babo to be peroxide of hydrogen.

From the ease with which it gives up its third atom of oxygen, ozone has been proposed when mixed with air, as a means of decolorising wax, stearin, and other organic substances which cannot be subjected to the fumes of sulphurous acid or chlorine, or at any rate only partially so. Ozone does not appear, however, to have been much, if at all adopted, for bleaching the above products, which are still, we believe, mostly whitened by the old method of exposure to the air.

Being one of the most energetic oxidising agents known, it is not surprising that the claims of ozone as a disinfectant should have found many supporters. One of its strongest advocates for this purpose is Dr Cornelius Fox, who says,——“Ozone should be diffused through fever-wards, sick rooms, the crowded localities of the poor, or wherever the active power of the air is reduced and poisons are generated. Its employment is especially demanded in our hospitals, situated as they mostly are in densely populated districts, where the atmosphere is almost always polluted by rebreathed air, decomposing substances and their products, and where no mere ventilation can be fully effective. If practicable, it would be highly advantageous to direct streams of sea-air, or air artificially ozonised into the fever and cholera nests of our towns. Ozone may be easily disseminated through public buildings, theatres, and other confined atmospheres, where numbers of people are accustomed to assemble in order to maintain the purity of the air.”

Another ardent believer in the hygienic value of ozone is Linder, who is also a strong advocate for its medical application, and recommends it both in the form of ozonised air and water in tuberculosis, rheumatism, asthma, and many other diseases. Linder, it is said, has set up an ozone manufactory, and vends ozone inhalations by the cubic foot.

To the contention of those who assert that it is impossible to convey such an unstable body as ozone into the blood without the ozone becoming decomposed into ordinary oxygen, this instability is denied upon the authority of Lehone and Hozeau, who state that it is less liable to change than is generally supposed, for they found, after working with it, that its peculiar odour remained on their hands and garments for some time. These views, largely shared by many others, as to the beneficial effects of ozone have, however, not been allowed to pass unchallenged. M. P. Thénard considered it important that both the public and medical men should be apprised of the erroneous character of the opinions generally entertained respecting the action of ozone on the organism. Ozone, he says, so far from exerting a beneficial effect, is one of the most energetic of poisons; and the serious accidents which have occurred in his own laboratory do not leave the slightest room for doubt in the matter.

Writing to the ‘Comptes Rendus,’[85] M. P. Thénard narrates the case of a guinea-pig, in which the beats of the pulse, normally 148 per minute, fell to 1/30th after the exposure of the animal for a quarter of an hour to an atmosphere charged with ozone. He states that under the influence of ozone, even when very largely diluted, the blood-corpuscles rapidly cohere and change their form. Other instances are recorded in which the blood, contrary to anticipation, has been found in the venous condition.

[Footnote 85: Lxxxii p. 1857.]

Drs Dewar and M’Kendrick found that ozone acted as a very powerful irritant upon the mucous membranes. Further, an experiment was made by placing some small birds in a mixture of oxygen and ozone, containing 10 per cent. of the latter. In two minutes the birds were dead.

Ozone is frequently present in the atmosphere, formed by electricity and perhaps by other means. Payen states that it does not amount to more than 1/450,000th weight, and 1/70000 by volume of atmospheric air. Other observers state that it varies in amount, according to height, locality, temperature, electricity, &c. Dr Buchanan says it is more abundant “on the sea-coast than inland, in the west than in the east of Great Britain, in elevated than in low situations, with south-west than with north-east winds, in the country than in towns, and on the windward than on the leeward side of towns.” According to the Scottish Meteorological Society, ozone is most prevalent in the atmosphere from February to June, when the average amount is 6, and lasts from July to January, when the average is 5·7. The maximum 6·2 is reached in May, and the minimum 5·3 in November.

These results are said to be in accordance with the conclusions arrived at by Dr Berigny and M. Hozeau.

Although there appears no ground for doubting that artificially prepared ozone, by reason of its actively disinfectant properties, may prove a valuable auxiliary in checking the spread of certain diseases; it seems far from satisfactorily established that the same quality is possessed by the ozone in the atmosphere, or on the contrary, as has been asserted, that certain ailments are caused by it. During an outbreak of influenza at Berlin, Schönbein states that the air contained a large quantity of ozone; a circumstance confirmed by Dr Pietra-Santa during the prevalence in another locality of the same epidemic, which it was imagined might be caused by the irritating effect of the ozone on the organs of respiration. Billard, Wolf, Bœckel, and Strambis all state that, during the prevalence of cholera at Strasbourg, Berlin, and Milan ozone was absent from the atmosphere, and that the decline of the malady was marked by its reappearance. Uhle ascribes the accumulation of malaria at night to the non-formation of ozone by solar heat.

The above facts have, however, been disputed by some observers, whilst others have refused to regard them as anything more than coincidences, and have indeed cited evidence of a totally opposite character; thus Grellois has stated that he found more ozone in a marsh than elsewhere.

Mr Kingzett has shown the incorrectness of Schönbein’s statement that, when oil of turpentine and other essential oils are oxidised by exposure to the air, ozone is formed. Schönbein was misled because from the oxidised oil and the air in its vicinity he obtained the ozone reaction with potassium iodide.

Mr Kingzett has demonstrated that the compound can be neither ozone nor hydrogen dioxide, because it is destroyed at the boiling point of oil of turpentine, viz. 160°, at which temperature ozone and hydrogen dioxide are permanent; besides which it resists to a certain extent the action of sodium thiosulphate, and its solution in water retains its properties after long-continued boiling. Mr Kingzett believes the active properties of the oxidised turpentine oil are due to the formation of monohydrated terpene oxide (C_{10}H_{16}O.H_{2}O).

One of the most delicate tests for ozone is potassium iodide, either alone or mixed with starch. A brown colour in the former case, a blue in the latter, indicates the liberation of iodine. In the ozometer, strips of paper saturated with starch and potassium iodide are exposed to the action of a definite volume of air in a dark chamber. The comparative quantities of ozone in different samples of air are judged of by the intensity of the colour compared with a fixed scale on which 1 is the lightest and 10 generally the darkest shade. See OZONOMETER.

Ozone acts as a reducing agent in certain curious cases. Thus, hydrogen peroxide and ozone reduce one another, water and oxygen being the sole products; and some substances, such as platinum black and manganese peroxide, convert it into oxygen without suffering change themselves, being probably oxidised and reduced alternately.

=OZONOM′ETER.= This name has been given to paper prepared with a mixed solution of starch and iodide of potassium. It is white, but is turned blue by ozonised air when exposed to it in a slightly moistened state.

The following are the proportions given by Schönbein for the preparation of the paper:——1 part of _pure_ iodide of potassium, 10 parts of starch and 200 of water. Lowe gives 1 part of iodide to 5 of starch; Moffatt, 1 to 2-1/2. The best arrowroot must be used for the starch. It must be dissolved in warm water and filtered, so that a clear solution is obtained.

The iodide is dissolved in another portion of water, and gradually added. The paper, cut in slips and previously soaked in distilled water, is placed in the mixed iodide and starch for several hours; and lastly, slowly dried in a cool dark place, the slips being hung horizontally. Schönbein’s papers require moistening with water after exposure before the trial is taken.

Payen’s ozonometer, which is an improvement on the above, is made of red litmus paper with half its surface impregnated with a 1% solution of potassium iodide. The portion of the paper becomes blue by contact with air containing ozone, in consequence of oxidation and the formation of potash. The unimpregnated portion of the paper undergoes no change unless the air contains ammoniacal vapours, and then the paper becomes blue over its entire surface.

M. Davy states that he has obtained very satisfactory results in the estimation of ozone in the atmosphere, by employing a mixture of iodide of potassium and arsenite of potassium.

The value of the ozonometer as an indicator of atmospheric ozone must be looked upon as uncertain, when it is borne in mind that there are other bodies besides ozone frequently present in the air, such as nitrous acid, chlorine, &c., which give similar reactions with the above reagents.

=PACK′FONG.= _Syn._ PAKFONG, CHINESE WHITE COPPER. An alloy formed by fusing together, in a covered crucible, arsenic, 2 parts, and copper clippings, 4-1/2 to 5 parts, arranged in alternate layers, and covered with a capping of common salt. The product contains about 10% of arsenic.

_Prop., &c._ White, slightly ductile, and permanent at ordinary temperatures; at a temperature below that of redness it suffers decomposition, with the extrication of fumes of arsenious acid. Formerly much used for the scales of thermometers and other instruments, dial plates, candlesticks, &c. It is now almost superseded by the alloy of nickel and copper called German silver, to which the name is also applied by some recent writers.

=PACK′ING.= As there is considerable art in packing brittle hollow-ware, as glass, china, &c., in such a way that it will stand exposure to the jolting, blows, and agitation of land carriage, it is better, when it is of much value, or in quantity, to employ a person qualified for the job. A man accustomed to packing such articles may be readily procured at any glassworks or china warehouse for a trifling consideration. When this cannot be done, it must be recollected that the great secret of safe packing consists in the articles being carefully preserved from undue pressure or contact with each other, yet so firmly arranged, and so surrounded with some material as hay, straw, sawdust, &c., that they cannot be shaken into such a condition by the ordinary contingencies of transport. Loose packing must always be avoided.

=PAD′DING.= Among calico printers this term is applied to the operation of impregnating the pores of their cloth with a mordant. It is now almost exclusively performed by means of a simple piece of machinery (padding machine), which essentially consists of——a ‘large reel,’ around which the unprepared cloth is wound——a ‘guide roller,’ over which it passes to smooth and adjust it before entering the liquor——a copper cylinder, or ‘dip-roller,’ nearly at the bottom of the ‘mordant-trough,’ under which it is carried from the guide-roller——a half-round polished ‘stretched-bar,’ to give it equal tension——a pair of ‘padded cylinders,’ to remove superfluous moisture——and, lastly, a ‘reel’ to receive the mordanted (‘padded’) cloth. The degree of tension is regulated by a weight suspended on a lever, and motion is given to the whole by an endless band from the driving shaft. This machine is also applicable to many of the operations of dyeing, bleaching, and starching textile fabrics.

=PAINT′ER’S CREAM.= _Prep._ Take of pale nut oil, 6 oz.; mastic, 1 oz.; dissolve, add of sugar of lead, 1/4 oz., previously ground in the least possible quantity of oil; then further add of water, q. s., gradually, until it acquires the consistence of cream, working it well all the time. Used by painters to cover their work when they are obliged to leave it for some time. It may be washed off with a sponge and water.

=PAINT′ING.= The art or employment of laying on colour. In the fine arts, the production of a picture or a resemblance in colours on a flat surface. The artistic and mechanical consideration of this subject does not come within the province of our volume; but notices of the leading materials employed by both artists and house painters are given under the respective names. See the various pigments, COLOURS, OILS, VARNISHES, &c., and _below_.

=Painting, Distem′per.= A method of painting generally adopted by the ancients. Water was the principal medium, but various gelatinous and albuminous ‘binders’ were added to fix the pigments. Of these the most important were glue, size, and white of egg. In modern distemper, as executed by the painters of theatrical scenery, panoramas, &c., spirit of turpentine is largely employed as a medium.

=Painting, Elydor′ic.= A method of painting invented by M. Vincent, of Montpelier, having for its object to combine the fresh appearance and finish of water colours with the mellowness of oil painting. The liquid employed as a vehicle for the pigments is an emulsion formed of oil and water by the intervention of certain portion of gum or mucilage.

=Painting, Enam′el.= In this variety of painting, vitrifiable colours are laid on thin plates of metals, and fused into it. The outline is first burnt in, after which the parts are filled up gradually, with repeated fusions at an enameller’s lamp, to the most minute finishing touches. “The enamel painter has to work, not with actual colours, but with mixtures which he only knows from experience will produce certain colours after the operation of the fire.” (Aikin.)

=Painting, Encaus′tic.= This method is very ancient, but is now seldom practised. According to Pliny, the colours were made up into crayons with wax, and the subject being traced on the ground with a metal point, they were melted on the picture as they were used. A coating of melted wax was then evenly spread over all, and when it had become quite cold was finally polished.

The art of encaustic painting, after lying dormant for about 15 centuries, was revived by Count Caylus, in 1753. In its new form, the wood or canvas to be painted on is first well rubbed over with wax, and then held before the fire, so that the wax may penetrate and fill up all the interstices, and form a perfectly even surface. The coloured pigments are next mixed with the powder noticed below, which is then rubbed smooth with some thick gum water, and applied with brushes in the same manner as ordinary water colours. When the painting is finished, and quite dry, it is brushed over with pure white wax in a melted state, the surface being equalised by the skilful application of heat; it is, lastly, polished off; as before.

_The powder._——To white wax, melted in an earthen pipkin, add, in small portions at a time, an equal weight of powdered mastic, stirring continuously until the whole is incorporated; then pour it into cold water, and afterwards reduce it to powder in a wedgwood-ware mortar. A small quantity only of this powder is used with light colours; but more is required with the darker ones, until, on approaching black, the two may be mixed in almost equal proportions.

=Painting, Fres′co.= This method of painting was known to the ancient Egyptians, and was commonly practised by the Greeks and Romans. It is confined to the decoration of the walls of buildings, and is executed by incorporating the colours with the still moist plaster, or gesso. The pigments employed are entirely mineral or vitreous. As it is extremely difficult to alter the work after the colours are once absorbed, or after the ground has hardened, the whole must be carefully designed before commencing the picture, and no more commenced at once than can be executed during the day.

Of all the varieties of painting, fresco is “undoubtedly the most virile, most sure, most resolute, and most durable” (Vasari), and the one most adapted for the purposes of historical painting in its grandest and most exalted forms. In comparison with it, it has been said that even oil painting is “employment fit only for women and children.” (Michael Angelo.)

=Painting, Glass.= See STAINED GLASS.

=Painting, Oil.= This well known and much practised method of painting takes its name from the vehicle employed for the colours. The last may be any of those of a permanent character, and whose natural tint is not altered by admixture with oil. Linseed, nut, and poppy oil, are those which are principally employed. The first requires the addition of ‘driers,’ and hence is generally used under the form of ‘boiled oil.’ Spirit of turpentine is commonly used to thin down the prepared colours, and the finished picture is frequently covered with a coat of varnish.

=Painting, Por′celain.= See POTTERY, STAINED GLASS, &c.

=Painting, Vel′vet.= Any of the ordinary non-corrosive pigments or liquid colours, thickened with a little gum, may be employed in this art; preference being, however, given to those that possess the greatest brilliancy, and which dry without spreading. See STAINS, &c.

=Painting, Water-colour.= In its strictest and modern sense, ‘water-colour painting’ means the painting on paper with colours diluted with water. The English school of water-colour painting has produced works which bear comparison with the great masterpieces in oil, and even surpass them in the delicacy of atmospheric effects. The old practice of making the entire drawing in light and shade by washes of Indian ink or neutral tints, and then adding the various local colours in transparent washes, has given place to the more healthy system of painting every object in its appropriate local colour at the outset.

=PAINTINGS.= Many valuable paintings suffer premature decay from the attacks of a microscopic insect, a species of acarus or mite. The best method of preventing this variety of decay, is to add a little creasote (dissolved in brandy or vinegar), or a few grains each of corrosive sublimate and sal ammoniac (dissolved in a little water), to the paste and glue used to line the picture, as well as to add a few drops of pure creasote or of an alcoholic or ethereal solution of corrosive sublimate to the varnish, when any is to be applied. If the destruction alluded to has already commenced, the painting should be at once carefully cleaned and re-lined, observing to employ one or other of the remedies just mentioned.

The most appropriate and only safe situation in which to keep paintings, is where there is a pure and moderately dry atmosphere. To protect pictures from the effects of damp, it has been suggested to dip the canvas into a solution of silicate of potash, and afterwards dried, previous to its being used. Impure air abounds in carbonic acid and sulphuretted hydrogen. It is the presence of the last in the air that blackens the ‘lights,’ and causes most of the ‘middle tints’ and ‘shades’ to fade; and it is exposure to damp that produces mouldiness and decay of the canvas. For this reason valuable paintings should not be kept in churches, nor suspended against heavy walls of masonry, especially in badly ventilated buildings. Excess of light, particularly the direct rays of the sun, also acts injuriously on paintings, since it bleaches some colours and darkens others.

The blackened lights of old pictures may be instantly restored to their original hue by touching them with peroxide of hydrogen, diluted with 6 or 8 times its weight of pure water. The part must be afterwards washed with a clean sponge and water. The most astonishing results have been produced in this way. See PEROXIDE OF HYDROGEN.

Pettenkofer observing the colours of many of the oil paintings in the Munich galleries apparently fading, discovered that the dim and grey appearance they then presented, was not really due to any decay of colour, but to a discontinuity of the molecules of the vehicle, and the resinous substances mixed with the pigments; the effect of which was to break up and lessen the mass of transparent colour and to diminish its intensity. This separation from each other, of the alternate particles, he conceived was owing to the shrinking and contraction they underwent after long years of exposure to a moist atmosphere. To remedy it Pettenkofer subjected the affected picture to two simple processes, which he is said to have found absolutely successful. The first, which he terms the ‘regeneration’ process, consists in enclosing the picture in a flat box, where it is exposed to the vapours of alcohol, part of which being absorbed by the resinous molecules, restore them to their original volume. Hence it follows that the gaps between the molecules being thus filled up, there is presented to the eye a continuous mass of transparent colour, as when the picture was freshly painted.

In the previous operation the resinous constituents only of the picture have been acted upon and restored to their normal condition. The hardened molecules of the oil which have been employed as a vehicle have likewise diminished in bulk, from the same causes, and in so doing have contributed to the lessening of the brightness of the picture. In cases where it is found the increased volume of resinous particles has failed to fill up the intervals between the shrunken oil molecules, Pettenkofer subjects the picture to a further process. In this, which he terms ‘nourishing it,’ the picture is simply rubbed over with balsam of copaiba.

Oil, which was formerly employed for this purpose, is very strongly condemned by Pettenkofer.

Oil paintings, as probably most of our readers are aware, are mostly executed either on wood (‘panel’) or canvas, now principally on the latter. Both these substances have to undergo a preliminary operation known as ‘priming,’ the priming being, in short, the ground on which the paint is placed. This priming may consist either of a number of layers composed of a mixture of chalk or plaster, with paste or glue, or else of a series of coats of oil colour. When a canvas or panel is prepared with the former, it is called ‘distemper priming,’ when with the latter, ‘oil priming.’ The distemper is the more quickly prepared, but is open to the objection of being easily broken, and of a liability to absorb moisture, by which it becomes liable to separate from the canvas.

If the priming be of oil colour it is desirable that the chief pigment used in making it should be white lead, and that if any other colours are added, they should be in comparatively small quantities. Dr R. Liebreich cites an example in which a departure from this precaution, persevered in from the middle of the 16th to that of the 17th century, by a celebrated school of Italian painters (the Bologna), has resulted in the destruction in their works of all the glazing of the picture, “so that those colours only can be recognised which either contain white, or are glazed on white.” Furthermore, that the dark priming used by these artists has caused the dark parts of their pictures to become still darker.

This priming which was of a reddish-brown colour, was composed of a mixture of bole Armenian and umber; and it is conjectured it was employed with the object of modifying or softening too violent contrasts of light and dark colours, and thus of easily securing effective chiaroscuro, and of aiding rapid execution.

The Dutch and Flemish painters mostly employed a light coloured priming; sometimes it was of a light oak colour. Vandyke is said to have used grey grounds for his pictures, and in some few instances dull red ones; and since his pictures are free from the objectionable qualities met with in the works of the Bologna artists, it has been surmised that in this method of working, he had recourse to impasto colouring.

In the selection of wood, which is subsequently to be used for the picture, considerable judgment and experience are required, that from the toughest and soundest oaks, nut trees, or cedar, being sought after. The cutting it into boards, and seasoning it, are also points exacting a great amount of time and care.

The backs of pictures, if made of wood, in addition to their liability to attacks from insects, not unfrequently warp, or fissures form in them, or they may become hopelessly rotten.

When the picture warps, it should be moistened with water at the back, on which it should be lain for 24 hours, at the end of which time, or sometimes less, it becomes perfectly straight. Fissures may be filled up by pieces of wood cut to the required size. Small pieces of rotten wood, if not too near the painting, may be cut out and the gaps filled up with wedge-shaped pieces of wood. Where the loss is insignificant it may be stopped up with cement. When the panel is very rotten and decayed, it may be necessary to remove the picture from it altogether, and to place it either on a new panel, or upon what Dr Liebreich regards as better still, a piece of canvas.

This is by no means so formidable and astonishing an operation as it may at first sight appear; in short, as will be directly shown, the picture may, if necessary, be freed from its priming even, without any difficulty.

Hacquin, of Paris, was one of the first to remove an oil painting from its base, and to place it upon a new one. He did this with one of Raphael’s Madonnas, in the gallery of the Louvre; and the same treatment has since been extended to the ‘Resurrection of Lazarus,’ by Sebastian del Piombo, one of the pictures in our National Gallery. This process is generally accomplished as follows:——

“First of all the surface of the picture is pasted over with gauze and paper; after that the wood is made straight by moistening, or, if necessary, by making incisions with the saw, into which cuneiform pieces of wood are driven. By means of a tenon-saw the panel is to be sawn into little squares, which must be removed by a chisel, and in this way the thickness of the wood is reduced to half an inch; it is then planed until it becomes no thicker than paper, and the rest is removed by means of a knife and with the fingers.

“The painting being thus severed from its basis, it can be fixed on canvas if the priming is sufficiently preserved. In the opposite case a mixture made of chalk and glue, or something of the kind, must be put on first, and very evenly smoothed after being dry. This done the new canvas has to be fixed upon it by means of a mixture of glue, varnish, and turpentine, and the substance of the picture pressed tightly and evenly against it by means of warm irons.”[86]

[Footnote 86: Liebreich.]

Defects in the priming of an oil painting, when they are confined to a slight separation of the priming of a canvas, may be remedied by pouring into the gap caused by the severance a little solution of size, and then pressing the separated surfaces gently together. Slight cracks must be filled up with fresh priming.

For paintings in which the whole of the priming seems insecure, or has extensively separated from the canvas, it is recommended to remove them entirely from the old basis and to transfer them to new panels or canvas.

The property of unchangeableness, or indisposition to fade, as exemplified in the retention of its freshness of colour by a picture, is one which, it is asserted, is very much more generally met with in the pictures of the Italian,[87] and Dutch painters of the 15th, 16th, and 17th centuries, than in those of the French and English schools of the last hundred years. Opinions have been advanced in explanation of this circumstance. One is, that the older masters used pigments and vehicles of much greater purity and freedom from adulteration than the latter generations of painters; another, that they worked by a method and prepared their colours by a process unknown since their time, in fact, that they were possessed of a technical secret, which, as they never divulged it, has died with them; a third, that they had choice of many colours unknown in the present day.

[Footnote 87: From the Italian school must be excepted that of Bologna.]

One of the later and most valuable contributions to our knowledge of these points has been made by Dr R. Liebreich, in his lecture “On the Deterioration of Oil Paintings,” delivered at the Royal Institution, March 1st, 1878, which also embraces the practical deductions to be drawn from the results of his investigations. The plan adopted by Dr Liebreich for unravelling the so-called secret by which the old masters so generally contrived to secure permanency for their colours was ingenious and logical; it consisted in dissecting the structure and chemically analysing the pigments, vehicles, &c., of the pictures of the pupils of the great masters, for “fortunately they painted with the same material and by the same methods as the masters, and thousands of pictures by the pupils, well preserved and in different stages of decay, may be easily secured.”

The third explanation previously given as a reason for the superior durability of the colouring of the old over the later oil paintings is thus disposed of by him. He says:——

“We meet very often with the idea that the old masters had been in possession of colours, that is, pigments, the knowledge of which has been lost, and that this accounts principally for the difference between the oil paintings of the 15th and 16th centuries, on the one hand, and that of the 18th and 19th on the other. But this is a great mistake. We know perfectly well the pigments used by the old masters; we possess the same and a considerable number of new ones, good as well as bad, in addition.”

He adds, “In using the expression of good and bad, I am thinking principally of their durability. From this point of view the pigments can be placed under three headings:——

“1. Those that are durable in themselves and also agree well with the other pigments with which they have to be mixed.

“2. Such as when sufficiently isolated remain unaltered, but when in contact with certain other pigments change colour, or alter the others, or produce a reciprocal modification.

“3. Those which are so little durable that, even when isolated from other pigments, the mere contact of the vehicle, the air, or the light, makes them in time fade, darken, or disappear altogether.

“_The old masters used without reserve only those belonging to the first of these three categories. For those belonging to the second they imposed on themselves certain limits and precautions. Those belonging to the third they did not use at all._

“That some of the modern masters have not followed these principles is not owing to a lost secret, but to the fact they disregarded those well known principles, and even consciously acted against them. In Sir Joshua Reynolds’ diary, for instance, we read that in order to produce certain tints of flesh, he mixed orpiment, carmine lake, and blue black together.

“Now, orpiment is one of the colours of the second category, carmine lake one of the third. That is to say, orpiment, as long as it remains isolated, keeps its brilliant yellow or reddish orange colour; but when mixed with white lead it decomposes, because it consists of sulphur and arsenic, and it moreover blackens the white lead, because the sulphur combines with it. Carmine lake, even if left isolated, does not stand as an oil colour, and, therefore, has been superseded by madder lake.

Unfortunately some of the most brilliant colours are perishable to such a degree that they ought never to be used; yet it seems to me that just in one branch of art, in which of late remarkable progress has been made, I mean landscape painting, the artists, in order to obtain certain effects of colour not easy to be realised, do not always resist the temptation to make use of a number of pigments, the non-durability of which is proved beyond doubt.”

Another point which Dr Liebreich regards as of much more importance even than the selection and treatment of their pigments, and in which he says the old masters exercised great discretion, was the more sparing use of the vehicles and liquids they mixed with their colours.

He points out that there are certain pigments which when mixed with the oil impede its drying, whilst others there are which hasten it. “Supposing now,” he says, “we should add to each of the different pigments the same quantity of oil, the drying of it would progress at different rates. But in reality this difference is very greatly increased by the fact that the different pigments require very different quantities of oil, in order to be ground to the consistency requisite for painting.”

Pettenkofer quotes the following figures given to him by one of the colour manufacturers:——

100 parts (weight) White lead require 12 parts of oil. ” ” Zinc white ” 14 ” ” ” Green chrome ” 15 ” ” ” Chrome yellow ” 19 ” ” ” Vermilion ” 25 ” ” ” Light red ” 31 ” ” ” Madder lake ” 62 ” ” ” Yellow ochre ” 66 ” ” ” Light ochre ” 72 ” ” ” Camel’s brown ” 75 ” ” ” Brown manganese ” 87 ” ” ” Terre verte ” 100 ” ” ” Parisian blue ” 106 ” ” ” Burnt terre verte ” 112 ” ” ” Berlin blue ” 112 ” ” ” Ivory black ” 112 ” ” ” Cobalt ” 125 ” ” ” Florentine brown ” 150 ” ” ” Burnt terra sienna ” 181 ” ” ” Raw terra sienna ” 140 ”

According to this table, a hundred parts of the quick drying white lead are ground with twelve parts of oil, and on the other hand, slow-drying ivory black requires one hundred and twelve parts of oil.

It is very important that artists should have an exact knowledge of these matters. But it seems to me that they are insufficiently known to most of them. All, of course, know perfectly how different the drying quality of different colours is. But that these different colours introduce into the picture so different a quantity of the oil, and how large the quantity is in the colours they buy, and, further, that the oil as well as the mediums or siccatives they add to dry the colours are gradually transformed into a caoutchouc-like opaque substance, which envelopes and darkens the pigments, and, moreover, that the oil undergoes, not in the beginning, but much later on, when it is already completely dry, changes of volume, and so impairs the continuity of the picture——all this is not sufficiently known. Otherwise, the custom of painting with the ordinary oil colours, to be bought at any colourman’s, would not have been going on for nearly a hundred years, in spite of all the clearly shown evil results——results due chiefly to the principal enemy of oil painting, that is to say, the oil.

A close optical examination and accurate study of the pictures of the French and English masters of the last hundred years have revealed to Dr Liebreich their principal defects, which he says are:——

1. Darkening of the opaque bright colours.

2. Fading of the transparent brilliant colours.

3. Darkening, and above all, cracking of the transparent dark colours. He states that these cracks are so characteristic and distinctive of the pictures of this period that they might be used as a test as to whether or not a picture really belonged to this school, or was only a copy.

This peculiar cracking in the paint is, according to Dr Liebreich, particularly observable in Guericault’s ‘Wreck of the Medusa’ in the Louvre, and also in Ingres’ ‘Portrait of Cherubini,’ and as the same defect is not to be seen in the works of the Dutch and Italian artists, the very rational inference to be drawn is that the methods followed by these schools were sounder than those adopted by their English and French successors. Dr Liebreich believes the cracks were owing to the practice of painting over one colour with another before the first was perfectly dry.

“The study of the alterations,” says Dr Liebreich “already fully developed within the last hundred years only, and their comparison with the works of the old masters would suggest the following rules for the process of painting:——

“1. That the oil should in all colours be reduced to a minimum, and under no form should more of it than absolutely necessary be introduced into a picture.

“2. All transparent colours which dry very slowly should be ground, not with oil at all, but with a resinous vehicle.

“3. No colour should be put on any part of a picture which is not yet perfectly dry, and above all, never a quick-drying colour upon a slowly-drying one which is not yet perfectly dry.

“4. White and other quick-drying opaque colours may be put on thickly. On the contrary, transparent and slowly-drying colours should always be put on in thin layers. If the effect of a thick layer of these latter is required, it must be produced by laying one thin layer over another, taking care to have one completely dry before the next is laid on. If transparent colours are mixed with sufficient quantity of white lead they may be treated like opaque ones.”

Dr Liebreich concludes his interesting lecture with some judicious advice on the subject of picture cleaning, and points out that, since different pictures require to be differently operated upon, all universal agents and methods suggested for the purpose are open to suspicion and should be discarded.

For pictures the varnish of which has become cracked or dim he recommends Pettenkofer’s treatment with alcoholised vapour, already described. For those in which the varnish may have become dark yellow, brown, or dirty, he advises its removal altogether, being very careful to specify the conditions under which this should be accomplished, and the risk the picture may run of being spoiled if entrusted to an unintelligent and ignorant manufacturer. “If a picture,” he says, “is throughout painted in oil, if its substance has remained sound and even, and it has been varnished with an easily soluble mastich or dammar varnish, there will be neither difficulty nor danger in removing the varnish. This can, in such a case, be done either by a dry process, that is by rubbing the surface with the tips of the fingers and thus reducing the varnish by degrees to a fine dust, or by dissolving the varnish by application of liquids which, when brought only for a short time into contact with the oil painting, will not endanger it. We have, however, seen that the works of the old masters are not painted with oil colours like those used by modern painters, but, on the contrary, that certain pigments, and especially the transparent colours used for glazing, were ground only with resinous substances. These latter have in the course of time been so thoroughly united with the layer of varnish spread over the surface of the picture that there no longer exists any decided limit between the picture and the varnish. It is in such pictures that a great amount of experience and knowledge of the process used for the picture, as well as precaution, are required, in order to take away from the varnish as much only as is indispensable, and without interfering with the picture itself.

“Numberless works of art have been irreparably injured by restorers, who, in their eagerness to remove dirt and varnish, attacked the painting itself. They then destroyed just that last finishing touch of the painting without which it is no longer a masterpiece.”

“The cleaner is, then, reminded that if the removal from the pictures of their varnish, when this is known to consist of a spirituous solution of the gums mastich or dammar, requires the amount of discretion and judgment before specified, still greater care and prudence are necessary when dealing with pictures whose surfaces have been covered with oil, oil varnish, or oleo-resinous varnish. All these substances, which in time more or less obscure the picture, form on its face a dark and opaque film, and this frequently requires for its removal the application of some agent, which, in dissolving the layer of varnish, is very liable at the same time to dissolve the substance of the picture also.”

As a recent instance of the injurious effects of injudicious picture cleaning, Dr. Liebreich mentions the case of a valuable picture in the Pitti Palace, at Florence, the ‘St John of Andrea del Sarto.’ The softness of the outline of the face of the figure, which he remembers previous to its attempted restoration, had been entirely destroyed, which disastrous result Dr Liebreich conceived had been caused by the entire removal of the glazing.

A new method for cleaning pictures is described by E. Von Bibra in the ‘Journal für Praktische Chemie.’ A very indistinct oil-painting was freed from dust with a feather, washed with a sponge and water, and then covered for eight minutes with a layer of shaving soap. The soap was then washed off with a brush and then left to dry. It was next thoroughly cleaned with linen cloth soaked in nitro-benzol. The picture was now distinct, but the colours dull. Finally, it was treated with olive oil, and a coating of quick-drying varnish laid on. (Academy, May 6th, 1878.)[88]

[Footnote 88: In giving insertion to the above, we do not venture to give an opinion as to its value or the reverse. We would recommend it to be read side by side with Dr Liebreich’s advice on picture cleaning, given above.——ED.]

=PAINTS.= In trade, this term is commonly applied to pigments ground with oil to a thick paste, ready to be ‘thinned down’ with oil or turpentine to a consistence adapted for application with a brush.

Paints are prepared on the small scale by grinding the dry pigments with the oil by means of a stone-and-muller; on the large scale they are ground in a colour mill. There are several pigments, as King’s yellow, Scheele’s green, verdigris, white lead, &c., which from their poisonous character cannot be safely ground by hand, except in very small quantities at a time, and then only by the exercise of extreme caution.

In mixing or thinning down paints for use it may be useful to mention that——for outdoor work, boiled oil is principally or wholly employed, unless it be for the decorative parts of houses, when a portion of turpentine and pale linseed oil is often added.——For in-door work, linseed oil, turpentine, and a little ‘driers,’ are generally used in the same way. The smaller the proportion of oil employed for the purpose, the less will be the gloss, and the greater the ultimate hardness of the coating. For ‘flatted white,’ &c., the colour being ground in oil, requires scarcely any further addition of that article, as the object is to have it ‘dead’ or dull. The best driers are ground litharge, and ground sugar of lead; the first for dark and middle tints, and the last for light ones.

To preserve mixed paints in pots from ‘skinning over’ or drying up, they should be kept constantly covered with water; or, what is better, with a thin film of linseed oil.

Brushes, when out of use, may be preserved in a similar manner to mixed paints. When dirty, or required for a paint of another colour, they may be cleaned with a little oil of turpentine, which may be either preserved for the same purpose another time, or may be allowed to deposit its colour, and then used to thin down paints as usual. In no case, however, should it be thrown back into the cistern or pan with the pure ‘turps.’

=Paints, Flex′ible.= _Prep._ Take of good yellow soap (cut into slices), 2-1/2 lbs.; boiling water, 1-1/2 gall.; dissolve, and grind the solution whilst hot with good oil paint, 1-1/4 cwt. Used to paint canvas.

=Paints, Vitrifi′able.= See ENAMEL, GLAZE, STAINED GLASS, &c.

=PALLA′DIUM.= Pd. A rare metal discovered by Dr Wollaston in the ore of platinum, in 1803.

_Prep._ 1. A solution of the ore of platinum in _aqua regia_, from which most of the metal has been precipitated by chloride of ammonium, is neutralised by carbonate of sodium, and then treated with a solution of cyanide of mercury; the white insoluble precipitate (cyanide of palladium) is next washed, dried, and heated to redness; the residuum of the ignition (spongy palladium) is then submitted to a gradually increased pressure, and welding at a white heat, so as to form a button, in a similar manner to that adopted with platinum. _Prod._ Columbian ore of platinum, 1%; Uralian do., ·25% to ·75%.

2. The native alloy of gold and palladium (from the Brazils) is submitted to the operations of quartation and parting, the nitric acid employed being of the density of 1·3; the silver is next precipitated from the solution by means of a solution of common salt or dilute hydrochloric acid, and the decanted supernatant liquid, after evaporation to one half, is neutralised with ammonia, and concentrated so that crystals may form; these (chloride of palladium and ammonium) are cautiously washed in a little very cold water, dried, mixed with borax, and exposed in a crucible to the strongest heat of a powerful blast furnace, when a solid button of pure palladium is formed.

_Prop., &c._ Palladium closely resembles platinum in appearance, fusibility, malleability, and ductility; but it is less dense, and has a rather more silvery colour than that metal; it is freely soluble in aqua regia, and is slowly attacked by nitric acid, but the other acids exert little or no action on it; heated to redness in the air, a very superficial blue or purple film of oxide forms on the surface, which is again reduced at a white heat. It melts at 156°——Wedgwood. Sp. gr. 11·3 to 12·1 (11·8——Wollaston; 12·14——Vauquelin). It readily unites with copper, silver, and some other metals, by fusion.

_Tests._ 1. The neutral solutions of palladium are precipitated in the metallic state by ferrous sulphate, dark brown by sulphuretted hydrogen, olive by ferrocyanide of potassium, and yellowish white by cyanide of mercury.——2. A drop of tincture of iodine placed on the surface of metallic palladium, and then evaporated by the heat of a spirit lamp, leaves a black spot. By the last two tests palladium is readily distinguished from platinum.

_Uses._ It has been employed to form the scales of mathematical and astronomical instruments, and is used in dentistry. Its alloy with silver is a very valuable white metal. It is also used for making the smaller divisions of grain and gramme weights. Palladium is not tarnished by sulphuretted hydrogen. An alloy of 1 part of palladium and 100 parts of steel is well adapted for cutting instruments which require to be perfectly smooth on the edge.

=PALMIT′IC ACID.= HC_{16}H_{31}O_{2}. Prepared from palmitin (_see_ next article), by saponification, as stearic acid is prepared from stearin. It forms pearly scales, and melts at 140° Fahr., like margaric acid, which it closely resembles.

=PAL′MITIN.= _Syn._ TRIPALMITIN. C_{3}H_{5} (C_{16}H_{31}O_{2})_{3}. The solid portion of palm oil, purified by crystallisation from hot ether. White; soluble in ether and slightly so in hot alcohol; melts at 118° Fahr.; by saponification it is converted into palmitic acid. (See _above_.)

=PALPITA′TION.= _Syn._ PALPUS, PALPITATIO CORDIS, L. A violent and irregular beating or action of the heart, either temporary or occasional. When it does not arise from sudden or violent agitation or distress of mind, it may be regarded as a symptom of a disturbance of the nervous functions by disease, in which case attention should be directed to the removal of the primary affection.

=PAL′SY.= See PARALYSIS.

=PANACE′A.= A term formerly applied to chose remedies which were supposed to be capable of curing all diseases, and still applied to some quack medicines.

=PANA′DA.= See BREAD JELLY (under JELLY).

=PAN′ARY FERMENTA′TION.= The vinous fermentation as developed in the dough of bread.

=PAN′CAKES.= These are essentially fried batter, variously enriched and flavoured, according to the taste of the cook. When they contain fruit, fish, meat, or poultry, or are highly seasoned or ornamented, they are commonly called FRITTERS.

_Prep._ (M. Soyer.) Break 2 to 4 eggs into a basin, add 4 small table-spoonfuls of flour, 2 teaspoonfuls of sugar, and a little salt; beat the whole well together, adding, by degrees, 1/2 pint of milk, or a little more or less, depending on the size of the eggs and the quality of the flour, so as to form a rather thick batter; next add a little ginger, cinnamon, or any other flavour at will; lastly, put them into the pan, and when set, and one side brownish, lay hold of the frying-pan at the extremity of the handle, give it a sudden but slight jerk upwards, and the cake will turn over on the other side; when this is brown, dish up with sifted sugar, and serve with lemon. See FRITTERS.

=PANCREAS.= This gland, popularly known as the sweet-bread, secretes a colourless and slightly viscid fluid, which possesses the properties of——1. Converting starch into sugar; 2. Of emulsifying fats and oils. And since it is necessary that the starchy and the fatty ingredients of the food should undergo this preparatory change before they are in a condition to become assimilated by the animal economy, it will be seen that _pancreatin_ (as the secretion from the pancreas is called) performs an important function in bodily nutrition.

With a knowledge of these facts before them, it is not surprising that the employment of pancreatin in disease should have been recommended by therapeutists. Dr Harley, we believe, first brought this remedy to the notice of medical men in 1858, since which time its principal advocate has been Dr Horace Dobell, whose method of preparing an emulsion from it, as well as for procuring the pancreatin pure and simple, are given below.

Bernard, correctly divining that the pancreatic fluid was concerned in the process of digestion, conceived that it aided the assimilation of the fatty and oily portions of the food, by saponifying them. Subsequent physiologists have, however, shown, “that the action of the pancreatic secretion is evidently to break up the large granules, crystals, and globules of oil and fat into myriads of minute particles of from 1/3000th to 1/15000th of an inch in diameter. In this way the fat is emulsified and converted into a milky liquid, which mixes freely with water, and passes through the tissues of the intestines into the lacteals.”[89]

[Footnote 89: Letheby.]

Pancreatin has an alkaline reaction, and putrefies very quickly. It seems to contain a nitrogenous organic principle, resembling ptyalin or diastase in properties. It is coagulated both by heat and nitric acid, and is one of the few secretions in which albumen is present in a soluble condition.

Even when rendered acid, pancreatin does not lose its power of emulsifying fatty bodies. At the moment of food being introduced into the stomach the pancreas gives out this secretion, which is not very abundant at first, but gradually continues to increase for about four hours, when it as gradually diminishes for three hours more, and then ceases altogether.

Bidder and Schmidt give the following as the composition of the pancreatic fluid or pancreatin:——

Water 900·76 Organic matter (pancreatin) 90·38 Chloride of sodium 7·36 Free soda 0·32 Phosphate of soda 0·45 Sulphate of soda 0·10 Sulphate of potassa 0·02 {Lime 0·54 Combinations {Magnesia 0·05 {Oxide of iron 0·02 ———————— 1000·00

=PANCREATIN.= _Syn._ PANCREATINUM. 1. (Pereira.) Cut the fresh pancreas of the pig, freed from fat and all foreign matters, into small pieces, and digest with ether. If the ether be afterwards distilled off from the filtered liquid, the pancreatin will be left as an oily product.

2. (Griffith.) It is obtained from the pancreas of recently killed animals by treating the colourless, viscous juice with alcohol, and drying the precipitate _in vacuo_. Pancreatin is given for stimulating the digestion of fatty compounds.

The ordinary dose is 10 grains, taken in a glass of wine or water after a meal.

Dr Dobell’s “Crude Pancreatic Emulsion” is prepared as follows:——After freeing from fat and all foreign matters the pancreas of a freshly-killed pig, 2-1/2 lbs. of purified pancreas are bruised in a marble mortar, and to it are added 2-1/2 lbs. of lard; these are well beaten together, and then to the mixture 3 lbs. of water are added, very gradually, so as to ensure the perfect absorption of the latter.

The pancreatised fat is prepared by shaking up one part of the ‘crude emulsion’ with three parts of ether, allowing the mixture to stand, drawing off the ethereal solution, and carefully distilling off the ether. The pancreatised fat remains. Dr Dobell says that pancreatised fat, unlike the crude fat, has no tendency to putrefy. His ‘purified pancreatic emulsion’ is made by mixing very carefully together 5 parts of pancreatised fat, 7-1/2 parts of distilled water, and 2-1/2 parts of rectified spirit, and flavouring with oil of cloves.

3. SACCHARATED PANCREATIN. Mr Mattison[90] adopts the following process for the preparation of this substance:——The pancreas is dissected and macerated in water acidulated with hydrochloric acid for about forty-eight hours, then separated, and the acidulated solution of pancreas passed through a pulp filter until it is perfectly clear. To this clear solution is then added a saturated solution of chloride of sodium, and allowed to stand until the pancreatin is separated. This is carefully skimmed off and placed upon a muslin filter, and allowed to drain, after which it should be washed with a less concentrated solution of sodium chloride, and then put under the press. When all the salt solution has been removed, and the mass is nearly dry, it is rubbed with a quantity of sugar of milk, and dried thoroughly without heat, after which it is diluted until ten grains emulsify two drachms of cod-liver oil.

[Footnote 90: ‘American Journal of Pharmacy.’]

=PANIFICA′TION.= The changes which occur in flour-dough under the influence of the fermentative process and heat, by which it is converted into bread.

=PAPA′VERINE.= _Syn._ PAPAVERINA. An alkaloid discovered by Merck in opium. It crystallises in needles; is insoluble in water; is slightly soluble in cold alcohol and in ether; and forms crystallisable salts with the acids which possess little solubility. The hydrochlorate, one of the most characteristic of these compounds, crystallises in beautiful colourless prisms, which possess a high refractive power, and are only very slightly soluble in dilute hydrochloric acid. Flückiger states that papaverine is much less active than thebaine, that it is not soporific either with men or animals, that it does not arrest diarrhœa, and is but slightly analgesic.

=PALAMOND.= Chocolate 1 oz.; rice flour, 4 oz.; potato arrowroot, 4 oz.; red sanders, in fine powder, 1 dr. Mix. (In the above, by chocolate is meant the cacao beans roasted and pulverised without addition. Indian arrowroot, or Tous les mois, may be substituted for the potato arrowroot.)

=PAPER.= _Syn._ CHARTA, PAPYRUS, L.; PAPIER, Fr. The limits of this work preclude the introduction of a description of the manufacture of this well-known and most useful article, which is now almost exclusively made by machinery of an elaborate and most ingenious description. We must, therefore, content ourselves with a short notice of a few of the preparations of the manufactured article. (See _below_.)

Good white paper should be perfectly devoid of odour, and when burnt it should leave a mere nominal amount of ash; digested in hot water, the liquid should be neutral to test paper, and not affected by sulphuretted hydrogen or the alkaline sulphurets, or by tincture of iodine. Coloured papers should not contain any deleterious matter.

=Paper, Antirheumatic.= _Syn._ CHARTA ANTIRHEUMATICA. (M. Berg.) Euphorbium 30 parts; cantharides, 15 parts; alcohol, 150 parts. Digest eight days, filter, and add resin, 60 parts; and turpentine, 50 parts. Thin paper is to be brushed over two or three times with this varnish.

=Paper, Atropine.= _Syn._ CHARTA ATROPIÆ. Paper is impregnated by steeping in solution of sulphate of atropia in such a manner that a piece 1/5th of an inch square shall contain 1/250th of a grain of the salt; a square of 1/10th of an inch the 1/1000th of a grain. This square inserted between the eyelid will dilate the pupil.

=Paper, Atropine, Gelatinised.= Tablets of gelatin are impregnated with sulphate of atropia, as above.

=Paper, Anti-asthmatic.= (P. Codex). _Syn._ CHARTA FUMIFERA, L. CARTON ANTI-ASTHMATIQUE, Fr. Unsized grey filtering paper, 12 oz.; nitre, 6 oz.; belladonna, stramonium, digitalis, lobelia inflata, phellandrium, all in powder, 1/2 oz. of each; myrrh and olibanum, in powder, 1 oz. each. Tear the paper in pieces and soak it in water till quite soft; drain off the greater part of the water, and beat it into a paste; incorporate with it the powders previously mixed. Then put into tinned iron moulds, and dry by a stove.

=Paper, Blistering.= See VESICANTS.

=Paper, Cloth.= This is prepared by covering gauze, calico, canvas, &c., with a surface of paper pulp in a ‘Foudrinier machine,’ and then finishing the compound sheet in a nearly similar manner to that adopted for ordinary paper.

=Paper, Co′loured.= For those papers which are merely coloured on one side the pigments, ground up with gum water or size, or the stains thickened with a little of the same, are applied with a brush, after which the sheets are suspended on a line to dry.

For paper coloured throughout its substance the tinctorial matter is usually mixed with the pulp in the process of manufacture; or the manufactured paper is dipped into a bath of the colouring substance, and then hung up to dry.

=Paper, Cop′ying.= _Prep._ Make a stiff ointment with butter or lard and black lead or lamp black, and smear it thinly and evenly over soft writing paper by means of a piece of flannel; the next day wipe off the superfluous portion with a piece of soft rag.

_Use, &c._ Placed on white paper and written on with a style or solid pen, a copy of the writing is left on the former. By repeating the arrangement, 2, 3, or more copies of a letter may be obtained at once. This paper, set up in a case, forms the ordinary ‘manifold writer’ of the stationers. The copying or transfer paper used for obtaining fac-similes of letters written with ‘copying-ink’ is merely a superior quality of bank-post paper.

=Paper, Em′ery.= See EMERY.

=Paper, Glass.= _Prep._ From powdered glass, as emery paper. Used to polish wood, &c. See GLASS (Powdered).

=Paper, Gout.= _Syn._ CHARTA ANTI-ARTHRITICA, L.; PAPIER FAYARD, Fr. _Prep._ 1. Euphorbium, 1 part; cantharides, 2 parts (both in powder); rectified spirit, 8 parts; ether, 3 parts; digest in a stoppered bottle, with frequent agitation, for a week; to the strained tincture add of Venice turpentine, 1 part; lastly, dip thin white paper into it, and dry the sheets in the air.

2. (Mohr.) Euphorbium, 1 dr.; cantharides, 4 dr.; rectified spirit (strongest), 5 oz.; make a tincture, to which add of Venice turpentine, 1-1/2 oz., previously liquefied with resin, 2 oz.; and spread the mixture, whilst warm, very thinly on paper. Used as a counter-irritant in gout, rheumatism, &c.

=Paper, Hydrograph′ic.= An absurd name given to paper which may be written on with simple water or with some colourless liquid having the appearance of water.

_Prep._ 1. A mixture of nut-galls, 4 parts, and calcined sulphate of iron, 1 part (both perfectly dry and reduced to very fine powder), is rubbed over the surface of the paper, and is then forced into its pores by powerful pressure, after which the loose portion is brushed off. Writes black with a pen dipped in water.

2. From persulphate of iron and ferrocyanide of potassium, as the last. Writes blue with water.

3. As the last, but using sulphate of copper instead of sulphate of iron. Writes reddish brown with water.

4. The paper is wetted with a colourless solution of ferrocyanide of potassium, and after being dried is written on with a colourless solution of persulphate of iron. Writes blue.

_Obs._ The above applications, we need scarcely say, are more amusing than useful. See SYMPATHETIC INK.

=Paper, Incombus′tible.= See INCOMBUSTIBLE FABRICS.

=Paper, Irides′cent.= _Prep._ (Beasley.) Sal ammoniac and sulphate of indigo, of each 1 part; sulphate of iron, 5 parts; nut-galls, 8 parts; gum Arabic, 1/8th part; boil them in water, and expose the paper washed with the liquid to (the fumes of) ammonia.

=Paper, Issue.= _Syn._ CHARTA AD FONTICULOS, L. _Prep._ (Soubeiran.) Elemi, spermaceti, and Venice turpentine, of each 1 part; white wax, 2 parts; melt them together by a gentle heat, and spread the mixture on paper. Used to keep issues open.

=Paper, Lithograph′ic.= _Prep._ 1. Starch, 6 oz.; gum Arabic, 2 oz.; alum, 1 oz.; make a strong solution of each separately, in hot water, mix, strain through gauze, and apply it whilst still warm to one side of leaves of paper, with a clean painting-brush or sponge; a second and a third coat must be given as the preceding one becomes dry; the paper must be, lastly, pressed, to make it smooth.

2. Give the paper 3 coats of thin size, 1 coat of good white starch, and 1 coat of a solution of gamboge in water; the whole to be applied cold, with a sponge, and each coat to be allowed to dry before the other is applied. The solutions should be freshly made.

_Use, &c._ Lithographic paper is written on with lithographic ink. The writing is transferred by simply moistening the back of the paper, placing it evenly on the stone, and then applying pressure a reversed copy is obtained, which, when printed from, yields corrected copies resembling the original writing or drawing. In this way the necessity of executing the writing or drawing in a reversed direction is obviated. See LITHOGRAPHY, INK, &c.

=Paper, Paste.= Boil white paper in water for five hours; then pour off the water, and pound the pulp in a mortar; pass it through a sieve and mix with some gum water or isinglass glue. It is used in modelling by artists and architects.

=Paper, Oiled.= _Prep._ Brush sheets of paper over with ‘boiled oil,’ and suspend them on a line till dry. Waterproof. Extensively employed as a cheap substitute for bladder and gut skin to tie over pots and jars, and to wrap up paste blacking, ground white lead, &c.

=Paper Parch′ment.= _Syn._ PAPYRIN, VEGETABLE PARCHMENT. _Prep._ 1. (Poumarède and Figuier.) Dip white unsized paper for half a minute in strong sulphuric acid, sp. gr. 1·842, and afterwards in water containing a little ammonia.

2. (W. E. Gaine, Patent 1857.) Plunge unsized paper for a few seconds into sulphuric acid diluted with half to a quarter its bulk of water (this solution being of the same temperature as the air), and afterwards wash with weak ammonia. This process, now extensively worked by Messrs De la Rue and Co., produces a much better material than does that of Poumarède and Figuier.

_Prop._ A tough substance, resembling animal parchment, and applicable to the same purposes. It is largely used for covering pots of pickles and preserves, and by the chemist for the intervening membrane in experiments in diffusion. See DIALYSER, DIALYSIS, &c.

=Paper, Protective.= Various attempts have from time to time been made to prepare paper which might make the fraudulent alteration of cheques and other documents difficult or impossible. These attempts have taken two different directions, which may be briefly described.

The first and best known method consists in printing, in some delicate and easily destroyed colour, a complicated pattern on the face of the paper. Any reagent which will remove the writing will, of course, destroy the pattern below, and so render the alteration evident. The cheques used by Messrs Coutts and Co. are fine examples of this kind of protection, the whole of the paper being printed over with the name of the firm in characters so delicate, that they can scarcely be read without the assistance of a lens.

The obvious objection to this method is, that it is possible for a skilful forger to replace the printed design before the completion of the alteration.

The other method consists in the introduction into the paper during its manufacture of some substance or mixture of substances which shall strike a characteristic colour when chemical agents are applied to the ink.

One of the earliest attempts of this kind was that of Stephenson, who introduced ferrocyanide of potassium into the pulp. When any acid was applied to the writing, Prussian blue was formed with the aid of the iron of the ink. In another process iodide of potassium and starch were introduced into the paper, the application of chlorine then producing a blue stain (iodide of starch), while in a third (Robson’s) the pulp was stained with the ingredients of common writing ink.

None of these methods gave, however, any very efficient protection against fraud, for in each case it was tolerably easy to restore the paper to its original condition. But another process which followed upon the others has proved more successful, and, when properly applied, gives a paper which is practically secure. This process was patented by Barclay, and consists in the introduction into the pulp of ferrocyanide of manganese. When any acid is applied to the writing on this paper the blue stain of Prussian blue appears. This can, it is true, be removed by alkalies, but in that case the manganese is precipitated as the brown peroxide, an effect also produced by bleaching powder. This brown stain can be removed by sulphurous acid, but in that case Prussian blue appears simultaneously, so that the forger has merely a choice between a brown and a blue stain.

When such paper is printed with a delicate design in some fugitive ink (common writing ink would be best), the greatest attainable safety is obtained.

Ferrocyanide of manganese is easily formed by adding to the pulp pure crystallised chloride of manganese, and rather more than an equal weight of ferrocyanide of potassium, both in solution. (Heaton.)

=Paper, Ra′′zor.= Smooth unsized paper, one of the surfaces of which, whilst in a slightly damp state, has been rubbed over with a mixture of calcined peroxide of iron and emery, both in impalpable powder. It is cut up into pieces (about 5 × 3 inches), and sold in packets. Used to wipe the razor on, which thus does not require stropping.

=Paper, Razor-strop.= From emery and quartz (both in impalpable powder), and paper pulp (estimated in the dry state), equal parts, made into sheets of the thickness of drawing paper, by the ordinary process. For use, a piece is pasted on the strop and moistened with a little oil.

=Paper, Re′sin.= _Syn._ POOR-MAN’S PLASTER; CHARTA RESINOSA, L. _Prep._ 1. Beeswax, 1 oz.; tar and resin, of each, 3 oz.; melted together and spread on paper.

2. (Ph. Bor.) Paper thinly spread over with black pitch. Calefacient, stimulant, and counter-irritant; in rheumatism, chest affections, &c.

=Paper, Rheu′matism.= See PAPERS, GOUT, and RESIN.

=Paper, Safe′ty.= _Syn._ PAPIER DE SURETÉ, Fr. White paper pulp mixed with an equal quantity of pulp tinged with any stain easily affected by chlorine, acids, alkalies, &c., and made into sheets as usual.

=Paper, Test.= _Syn._ CHARTA EXPLORATORIA, L. Under this head may be conveniently included all the varieties of prepared paper employed in testing. For this purpose sheets of unsized paper or of good ordinary writing paper (preferably the first), are uniformly wetted with a solution of the salt, or with a cold infusion or decoction of the tinctorial substance in distilled water, and are then hung up to dry in a current of pure air; they are, lastly, cut into pieces of a convenient size, and preserved in closed bottles or jars. For use, a small strip of the prepared paper is either dipped into or moistened with the liquid under examination, or it is moistened with distilled water and then exposed to the fumes. A single drop, or even less, of any liquid may be thus tested.

The following are the principal test papers and their applications:——

PAPER, BRAZIL-WOOD. From the decoction. Alkalies turn it purple or violet; strong acids, red.

PAPER, BUCKTHORN. From the juice of the berries. Reddened by acids.

PAPER, CHERRY-JUICE. As the last.

PAPER, DAHLIA, GEORGINA P. From an infusion of the petals of the violet dahlia (_Georgina purpurea_). Alkalies turn it green; acids red; strong caustic alkalies turn it yellow. Very delicate.

PAPER, ELDERBERRY. From the juice of the berries. As the last.

PAPER, INDIGO. From a solution of indigo. Decoloured by chlorine.

PAPER, IODINE OF POTASSIUM. _a._ From the solution in distilled water. Turned blue by an acidulated solution of starch.

_b._ From a mixture of a solution of iodide of potassium and starch paste. Turned blue by chlorine, ozone, and the mineral acids, and by air containing them.

PAPER, LEAD. From a solution of either acetate or diacetate of lead. Sulphuretted hydrogen and hydrosulphuret of ammonia turn it black.

PAPER, LITMUS. In general, this is prepared from infusion of litmus, without any precaution, but the following plan may be adopted when a superior test paper is desired;——

_a._ (Blue.) Triturate commercial litmus, 1 oz., in a wedgwood-ware mortar, with boiling water, 3 or 4 fl. oz.; put the mixture into a flask, and add more boiling water until the liquid measures fully 1/2 pint; agitate the mixture frequently until it is cold, then filter it, and divide the filtrate into two equal portions; stir one of these with a glass rod previously dipped into very dilute sulphuric acid, and repeat the operation until the litmus infusion begins to look very slightly red, then add the other half of the filtrate, and the two being mixed together, dip strips of unsized paper into the liquid, in the usual manner, and dry them. Acids turn it red; alkalies blue. The neutral salts of most of the heavy metals also redden this, as well as the other blue test papers that are affected by acids.

_b._ (Red.) The treatment of the whole quantity of the infusion (see _above_) with the rod dipped in dilute sulphuric acid is repeated until the fluid begins to look distinctly red, when the paper is dipped into it as before. The alkalies and alkaline earths, and their sulphides, restore its blue colour; the alkaline carbonates and the soluble borates also possess the same property. Very sensitive. An extemporaneous red litmus paper may be prepared by holding a strip of the blue variety over a pot or jar into which 2 or 3 drops of hydrochloric acid have been thrown.

PAPER, MALLOW. From an infusion of the purple flowers of the common mallow. Affected like ‘dahlia paper.’

PAPER, MANGANESE. From a solution of sulphate of manganese. Ozonised air blackens it.

PAPER, RHUBARB. From a strong infusion of the powdered root. Alkalies turn it brown; but boracic acid and its salts do not affect it. Very sensitive.

PAPER, ROSE. From the petals of the red rose, as the last. Alkalies turn it bright green. Dr A. S. Taylor recommends the infusion to be very slightly acidulated with an acid before dipping the paper into it. More sensitive than turmeric paper.

PAPER, STARCH. From a cold decoction of starch. Free iodine turns it blue.

PAPER, SULPHATE OF IRON. From a solution of ferrous sulphate. As a test for hydrocyanic acid and the soluble cyanides.

PAPER, TURMERIC. From decoction of turmeric (2 oz. to the pint). It is turned brown by alkalies, and by boracic acid and the soluble borates. It is not quite so susceptible as some other tests, but the change of colour is very marked and characteristic.

=Paper, Tra′′cing.= _Prep._ Open a quire of smooth unsized white paper, and place it flat upon a table, then apply, with a clean ‘sash tool,’ to the upper surface of the first sheet, a coat of varnish made of equal parts of Canada balsam and oil of turpentine, and hang the prepared sheet across the line to dry; repeat the operation on fresh sheets until the proper quantity is finished. If not sufficiently transparent, a second coat of varnish may be applied as soon as the first has become quite dry.

2. Rub the paper with a mixture of equal parts of nut oil and oil of turpentine, and dry it immediately by rubbing it with wheaten flour; then hang it on a line for 24 hours to dry.

_Obs._ Both the above are used to copy drawings, writing, &c. If washed over with ox-gall and dried, they may be written on with ink or water colours. The first is the whitest and clearest, but the second is the toughest and most flexible. The paper prepared from the refuse of the flax-mills, and of which banknotes are made, is also called ‘tracing paper,’ and sometimes ‘vegetable paper.’ This requires no preparation; but though very flexible, it has little strength.

=Paper, Var′nished.= Before proceeding to varnish paper, card-work, pasteboard, &c., it is necessary to give it 2 or 3 coats of size, to prevent the absorption of the varnish, and any injury to the colour or design. The size may be made by dissolving a little isinglass in boiling water, or by boiling some clean parchment cuttings until they form a clear solution. This, after being strained through a piece of clean muslin, or, for very nice purposes, clarified with a little white of egg, is applied by means of a small clean brush called by painters a sash tool. A light, delicate touch must be adopted, especially for the first coat, lest the ink or colours be started, or smothered. When the prepared surface is perfectly dry, it may be varnished in the usual manner. See MAPS, VARNISH, &c.

=Paper, Wa′′fer.= See WAFERS.

=Paper, Waxed.= _Prep._ Place cartridge paper, or strong writing paper, on a hot iron plate, and rub it well with a lump of beeswax. Used to form extemporaneous steam or gas pipes, to cover the joints of vessels, and to tie over pots, &c.

=PAPER HANG′INGS.= The ornamental paper used to cover the walls of rooms, &c. Under the old system, the paper, after being sized and prepared with a ground colour, had the pattern produced on it by the common process of ‘stencilling,’ a separate plate being employed for each colour that formed the pattern. To this succeeded the use of wooden blocks, the surface of which bearing the design in relief, and being covered with colour, was applied by simple hand pressure on the paper, in a precisely similar manner to that adopted in the block-printing of calicoes. The cylinder calico-printing machine has now been successfully applied to the manufacture of paper hangings.

The colours employed for paper hangings are——

BLACKS.——Frankfort, ivory, and blue black.

BLUES. Prussian blue, verditer, and factitious ultramarine.

BROWNS. Umber (raw and burnt), and mixtures.

GRAYS. Prussian blue and blue black, with Spanish white.

GREENS. Brunswick green, Scheele’s g., Schweinfurt g., and green verditer; also mixtures of blues and yellows.

REDS. Decoctions of Brazil wood (chiefly), brightened with alum or solution of tin; the red ochres; and, sometimes, red lake.

VIOLETS. Decoction of logwood and alum; also blues tempered with bright red.

YELLOWS. Chrome yellow, decoction of French berries or of weld, terra di sienna, and the ochres.

WHITES. White lead, sulphate of baryta, plaster of Paris, and whiting, and mixtures of them.

The vehicle employed to give adhesiveness and body to the colours is a solution of gelatin or glue, sufficiently strong to gelatinise on cooling.

The satiny lustre observable in some paper hangings (SATIN PAPERS) is produced by dusting finely powdered French chalk over the surface, and rubbing it strongly with a brush or burnisher. The ground for this purpose is prepared with plaster.

FLOCK and VELVET PAPERS are produced by covering the surface of the pattern with a mordant formed with boiled oil thickened with white lead or ochre, and then sprinkling powdered woollen flocks on it. These are previously dyed, and ground to the required fineness in a mill.

=PAPIER-MÂCHÉ.= Pulped paper moulded into forms. It possesses great strength and lightness. It may be rendered partially waterproof by the addition of sulphate of iron, quicklime, and glue or white of egg to the pulp; and incombustible by the addition of borax and phosphate of soda. The papier-mâché tea-trays, waiters, snuff-boxes, &c., are prepared by pasting or glueing sheets of paper together, and then submitting them to powerful pressure, by which the composition acquires the hardness of board when dry. Such articles are afterwards japanned, and are then perfectly waterproof.

The refuse of the cotton and flax mills, and numerous other substances of a like character, are now worked up as papier-mâché, and the manufactured articles formed of them are indistinguishable from those prepared directly from paper.

=PAPIN’S DIGESTER= is a strong, closed, iron vessel, in which water can be heated above 212° F., thereby acquiring a temperature that adds considerably to its solvent powers. This apparatus is put to many useful applications in the arts, of which one is the speedy extraction of gelatin from the earthy matter of bones. The bones may be boiled for hours at 212° without any such effect being produced. The high temperature acquired by the water is effected by the confinement of the steam, the internal pressure of which can be regulated by means of a safety valve attached to the vessel. By this arrangement the water may be kept at any uniform temperature above 212° at pleasure. Professor Junichen[91] recommends the use of the digester for the purpose of boiling meat and other food. It appears from the author’s experiments that the time for cooking various articles of daily consumption is much shorter when effected under strong pressure, while a great saving of fuel is also effected.

[Footnote 91: ‘Chemical News.’]

=PAPY′RIN.= See PAPER (Parchment).

=PAR′ACHUTE.= In aërostation, an instrument or apparatus having for its object to retard the descent of heavy bodies through the air. The only form of parachute which has been hitherto adopted with success is that of the common umbrella when extended. The materials of which the apparatus is made are canvas and cord, both light but strong, and carefully put together. The car to contain the adventurer resembles that of the balloon, only smaller.

It is estimated that a circular parachute, to descend in safety with an adult, weighing, with the apparatus, 225 lbs., must have a diameter of at least 30 feet. Its terminal velocity would then be at the rate of 12 to 13 feet per second, or about 6-1/2 miles per hour; and the shock experienced on contact with the earth would be equal to that which the aëronaut would receive if he dropped freely from a height about 2-1/2 feet.

Several descents from balloons, after they have acquired a great elevation, have been effected without accident by means of parachutes. Unfortunately, however, any want of integrity in the machine, or any accident which may happen to it after its detachment from the balloon, is irreparable and fatal.

=PARACYAN′OGEN.= The brown solid matter left in the retort when cyanide of mercury is decomposed by heat. It is isomeric with cyanogen.

=PARAFFIN.= _Syn._ TAR-OIL STEARIN. This remarkable hydrocarbon is one of the several substances discovered by Reichenbach in WOOD-TAR.

_Prep._ 1. (From WOOD-TAR. Reichenbach.) Distil beech-tar to dryness, rectify the oily portion of the product which is heavier than water until a thick matter begins to rise, then change the receiver, and moderately urge the heat as long as anything passes over; next digest the product in the second receiver, in an equal measure of alcohol of ·833, gradually add 6 or 7 parts more of alcohol, and expose the whole to a low temperature; crystals of paraffin will gradually fall down, which, after being washed in cold alcohol, must be dissolved in boiling alcohol, when crystals of pure paraffin will be deposited as the solution cools.

2. (From COAL——James Young, Patent 1850.) The details of this process for obtaining paraffin and its congeners by the slow distillation of coal (preferably ‘Boghead’) are given in our article on PARAFFIN OIL. The solid paraffin is separated from the last products, or ‘heavy oils,’ by artificial cold; it is then melted and run into moulds.

3. (From RANGOON PETROLEUM——Patent.) In this process, which is worked by Price’s Candle Company, superheated steam is employed as the heating agent. The paraffin, or ‘BELMONTINE,’ as it is called, is the last product which distils over.

4. (From PEAT.) The various processes which have been suggested for obtaining paraffin from peat, turf, &c., are similar in principle to Young’s. The great point is to conduct the distillation at as low a temperature as possible.

_Prop._ A white, hard, translucent body, melting at 110° Fahr. and upwards, according to its source, and burning with a bright white flame. It has great stability——sulphuric acid, chlorine, and nitric acid below 212° exerting no action upon it. Dr Anderson states that its composition and properties vary with the source from which it is derived. With respect to the melting point, this variation is very remarkable. Thus, Young’s paraffin, from Boghead coal, melts, according to the observations of Dr Anderson, at 114°, while that from Rangoon petroleum (‘belmontine’) melts at 140°, and that from turf at 116°.

_Uses._ Paraffin is now largely used for making candles, for which purpose it is specially adapted, being a most elegant substance, and surpassing all other candle materials, even spermaceti, in illuminating power. Its property of not being acted upon by acids or alkalies renders it suitable for stoppers for vessels holding chemical liquids; also for electrotype moulds. It is not acted upon by ozone, so that it has been employed with great advantages in experiments on this body for rendering air-tight the joints formed by the union of glass tubes. As it contains no oxygen, it might be employed to protect oxydisable metals like sodium and potassium from contact with the air. One use of paraffin candle-ends will commend them to the ladies of the household——a small piece of paraffin added to starch will be found to give a gloss and brilliancy of surface to the starched linen that can be obtained by no other addition.

=PARAFFIN OIL.= See OILS.

=PARAL′YSIS.= _Syn._ PALSY. A loss or considerable diminution of power of voluntary motion, or functional action, of any part of the body. In its most usual form one side only of the body is affected. It not uncommonly seizes the lower extremities, or all parts below the pelvis; sometimes the arms only; and occasionally a part, as one side of the face, one eyelid, the tongue, or the muscles of deglutition. In these cases the speech frequently becomes indistinct and incoherent, and the memory and judgment impaired, whilst the distorted features assume a more or less revolting aspect.

The causes of paralysis are various. It may be occasioned by pressure on particular parts of the brain, the spinal marrow, or the nerves; by poisons, the long-continued use of sedatives, local injuries, the sudden suppression of profuse and habitual evacuations, and by whatever tends to greatly relax or enervate the system. It may also be a consequence of an attack of apoplexy, or it may be symptomatic of other diseases, as scrofula, syphilis, and worms. When it is of a distinctly local character it may arise from excessive use or undue employment of the part or organ. That of old age is, probably, a mere consequence of the failing nervous energy of the system being unequally distributed.

Palsy usually comes on with a sudden and immediate loss of the motion and sensibility of the parts; but in a few instances it is preceded by a numbness, coldness, and paleness; and sometimes by slight convulsive twitches. If the disease affects the extremities, and has been of long duration, it not only produces a loss of motion and sensibility, but likewise a considerable flaccidity and wasting away of the muscles of the parts affected.

When palsy attacks any vital part, such as the brain, heart, or lungs, it soon terminates in death.

The treatment of paralysis depends upon a careful consideration of its cause. The first object should be, as far as possible, to remove any compressing force, and to gradually arouse the torpid portion of the nervous system. In general, more or less depletion will be found beneficial, together with rather active purgation, and nervous stimulants, as ammonia, musk, &c. Blisters to the head and neck are also appropriate. With the debilitated and aged, venesection must be avoided. Stimulant and rubefacient frictions and liniments, the vapour bath, and other like remedies, also frequently prove useful. In local attacks of the disease, as the loss of use of one of the hands, arms, legs, &c., no agent has proved so generally successful as voltaic electricity. For this purpose the current should be in one direction only, and continued uninterruptedly for some time daily. When the direction of the current is alternate, with slight shocks, as in the common coil machine, this agent is of doubtful utility, except for occasional use. In all cases medical aid should be sought as early as possible.

=PARANAPH′THALIN.= _Syn._ ANTHRACEN. See ANTHRACEN.

=PARAPEC′′TIN.= See PECTIN.

=PAR′ASITES.= The parasitical animals that infest the human body are referred to under the heads ACARI and PEDICULI.

=Parasites, Human.= The following is a list of the principal parasites infesting man. It is extracted from the ‘Dictionary of Hygiène,’ of Wynter Blyth, who states that he has arranged it, with some slight alterations, from a table in Dr Aitken’s ‘Science and Practice of Medicine.’ The two first divisions include animal parasites, the third vegetable ones. No. 1, or _Entozoa_, are animal parasites found inside the human body; No. 2, those found outside; No. 3, consisting of vegetable parasites, comprises _Entophyta_ and _Epiphyta_, the former existing in the interior, and the latter on the exterior of the human body. Some of the principal parasites have already been described and figured in these pages.

I. _Entozoa._

Acephalocystis endogena, _liver_. ” multifida, _brain_. Anchylostomum, seu Sclerostoma duodenale, _intestines_. Anthomia canicularis, _intestines_. Ascaris alata ” ” lumbricoides ” ” mystax ” Bilharzia seu Distoma hæmatobia, _portal and venous system_. Bothriocephalus cordatus, _intestines_. ” latus ” Cysticercus cellulosæ, seu telæ cellulosæ (C. of Tenia solium), _muscles_. Cysticercus of Tæniæ marginata (C. tenuicollis), _intestines_. Dactylius aculeatus, _urinary bladder_. Diplosoma crenatus. Distoma seu Distomum crassum, _duodenum_. ” hepaticum seu Fasciola hepatica, _gallbladder_. ” heterophryes, _intestines_. ” lanceolatum, _hepatic duct_ ” oculi humani seu ophthalmobium, _capsule of crystalline_. Ditrachycerus rudus, _intestines_. Echinococcus hominis (hydatid of Tænia echinococcus), _liver, spleen, and omentum_. Filaria bronchialis seu trachealis, _bronchial glands_. ” seu dracunculus medinensis, _skin and areolar tissue_. ” sanguinis hominis, _blood_. ” oculi seu lentis, _eye_. Hexathrydium pinguicola, _ovary_. ” venarum, _venous system_. Monostoma lentis, _crystalline_. Œstrus hominis, _intestines_. Oxyuris vermicularis, ” Pentastoma constrictum, _intestines and liver_. ” denticulatum, _intestines_. Polystroma pinguicola, _ovary_. ” sanguicola seu verarum, _venous system_. Spiroptera hominis, _urinary bladder_. Strongylus seu Eustrongylus bronchialus, _bronchial tubes_. ” seu Eustrongylus gigas (Acarus renalis), _kidney and intestines_. Tænia acanthotrias, _intestines_. ” elliptica, ” ” flavopuncta, ” ” lophosoma, ” ” mediocanellata, ” ” nana, _intestines and liver_. ” solium, _intestines_. Tetrastoma renale, _kidney_. Trichina spiralis, _muscles_. Tricocephalus dispar, _intestines_.

II. _Ectozoa._

Demodex seu Acarus folliculorum, _sebaceous substance of cutaneous follicles_. Pediculus capitas (head louse). ” corporis seu vestimenti (body louse). ” palpebrarum (brow louse). ” pubis, Phthirius inguinalis (crab-louse). ” tubescetium, _phthiriasis_ (_lousy disease_). Pulex penetrans (chigoë), _skin, cellular tissue_. Sarcoptes seu Acarus scabiei (itch insect), _scabies_.

III. _Entophyta and Epiphyta._

Achorion Lebertii (Tricophyton tonsurans), _Tinea tonsurans_. ” Schönleinii, _Tinea favosa_. Chionyphe Carteri (fungus of Mycetoma), _deep tissues, bones of hands and feet_. Leptothrix buccalis (alga of the mouth). Microsporon Audouini, _Tinea decalvans_. ” Furfur, _Tinea versicolor_. ” mentagrophytes, _follicles of hair in sycosis or mentagra_. Oïdium albicans (thrush fungus), _mouth, mucous, and cutaneous surfaces_. Puccinia favi, _Tinea favosa_. Sarcina ventriculi, _stomach_. Torula cerevisiæ (Cryptococcus cerevisiæ, yeast plant), _stomach, bladder, &c._ Tricophyton sporuloïdes, _Tinea polornia_.

=PARATARTAR′IC ACID.= See RACEMIC ACID.

=PARCH′MENT.= See VELLUM, and PAPER (Parchment).

=PARCHMENT PAPER.= See PAPER.

=PAREGOR′IC.= See TINCTURE OF CAMPHOR (Compound).

=Paregoric Scotch.= See TINCTURE OF OPIUM (Ammoniated).

=PAREI′RA BRA′VA.= See VELVET LEAF.

=PARR.= A name applied to the salmon until near the end of its second year, when it loses its dark lateral bars by the superaddition of a silvery pigment. It was formerly regarded as a distinct species.

=PARS′LEY.= _Syn._ PETROSELINUM, L. This well-known herb is the _Apium petroselinum_. The root is diuretic; the fruit (seed) carminative; the leaves are a pleasant stimulating salad and condiment, and are much used to flavour broth and soup. “The fruit is a deadly poison to parrots.” (Lind. _ex_ Burnett.)

=PARS′NIP.= The root of _Pastinacea sativa_. The parsnip is native to England and Ireland, but does not grow in Scotland. It is likewise met with in many parts of Europe and in northern Asia. In the wild state the root is somewhat acrid, and injurious effects have been known to have followed its use as a food. By cultivation, however, it loses both its acridity and dangerous properties, and forms a table vegetable, not in universal favour.

In the Channel Islands parsnips constitute the winter food of cows; and these animals when fed upon them are said to yield butter of a better quality than can be obtained from them when partaking of any other fodder.

The flesh of cattle fed on the parsnip is also highly commended. In the North of Ireland the juice of the root, mixed with hops and yeast, is made into a fermented liquor. Parsnip wine is an agreeable alcoholic beverage.

_Composition of the Parsnip._

Nitrogenous matter 1·1 Starch 9·6 Sugar 5·8 Fat 0·5 Salts 1·0 Water 82·0 —————— 100·0

=PASTE.= _Syn._ PASTA, L.; PÂTE, Fr. This word is very loosely applied to substances and preparations differing so widely from each other, that it would be scarcely possible to class them together. We shall, therefore, refer the reader to the individual articles. The pastes (pâtes) of French pharmacy are compound medicines of the consistence of hard dough, and which do not stick to the fingers. They are formed of sugar and gum, dissolved in water or in some medicated liquid. They are evaporated so as to unite these principles by degrees, and give them the pliancy and the firmness of paste. They are employed internally in doses more or less variable in a similar manner to lozenges. “Pâtes, properly so called, are divided into transparent, or such as are made without agitation, like jujubes of brown liquorice; and opaque, or such as are made with agitation, like the pâtes of marshmallow, lichen, &c.” (Trousseau and Reveil.) See PASTES (Artificial Gems), PASTRY, and _below_.

=Paste, Adhesive.= Let 4 parts, by weight, of glue soften in 15 parts of cold water for fifteen hours, after which the mixture must be moderately heated until it becomes quite clear. To this mixture 65 parts of boiling water are to be added without stirring. In another vessel 30 parts of starch paste are stirred up with 20 parts of cold water, so that a thin milky fluid is obtained without lumps. Into this the boiling glue solution is poured, with constant stirring, and the whole is kept at the boiling temperature. When cooled the 10 drops of carbolic acid are to be added to the paste. This paste possesses great adhesive power, and may be used for leather, paper, or cardboard with great success. It must be preserved in closed bottles to prevent evaporation of the water, and will, in this way, keep good for years. (‘Dingler’s Journal.’)

=Paste, Al′mond.= _Syn._ PASTA AMYGDALINA, P. AMYGDALARUM, P. REGIA, L.; PÂTE ROYALE, Fr. _Prep._ 1. (MOIST.)——_a._ Take of blanched Valentia almonds, 4 oz.; reduce them to a very smooth paste by patient pounding in a clean mortar, adding, towards the last, a little rose water, with some eau de Cologne, or 3 or 4 drops of otto of roses or neroli, or an equivalent quantity of any other perfume, according to the fancy of the artiste.

_b._ From bitter and sweet almonds (blanched), equal parts; rose water, q. s. It requires no other perfume.

_c._ To either of the preceding add of spermaceti, 1/2 oz. The white of an egg, or 1/4 oz. of white soap, is added by some makers. With about 1/2 dr. of powdered camphor to each oz. of the above it forms the ‘camphorated almond paste’ of the shops.

_d._ Take fine Narbonne honey and white bitter paste (see _below_), of each 1 lb.; beat them to a smooth paste, then add, in alternate portions, of oil of almonds, 2 lbs.; yolks of 5 eggs; and reduce the whole to a perfectly homogeneous pasty mass. Much esteemed. It is commonly sold under the name of ‘honey paste,’ ‘pâte royale,’ &c. In a similar manner are made nosegay, orange, rose, vanilla, and other like pastes having almonds for a basis, by merely adding the respective perfumes.

2. (PULVERULENT.)——_a._ (Gray.) Prepared from the cake of bitter almonds from which the oil has been thoroughly expressed by drying, grinding, and sifting it.

_b._ (Bitter white.) As the last, but the almonds are blanched before being pressed.

_c._ (Sweet white.) As the last, but using sweet almonds.

_Obs._ All the above are used as cosmetics, to soften and whiten the skin, prevent chaps, abrasions, chilblains, &c. The honey paste, and the sweet and bitter white pastes, are those most esteemed. (See _below_.)

=Paste, Almond.= (In confectionery.) _Prep._ 1. Take of Valentia almonds, 3 lbs.; bitter do., 1/4 lb.; blanch them, and reduce them to a very smooth paste by pounding, then put them into a clean copper pan along with white sugar and good gum Arabic, of each 1 lb. (the last previously dissolved in about a pint of water;) apply a gentle heat, and stir until the whole is mixed and has acquired a proper consistence, then pour it out on a smooth, oiled, marble slab, and when cold cut it into squares.

2. As the last, but when the mixture has acquired the consistence of thick honey, setting it aside to cool; when nearly cold, the whites of 6 eggs are to be added, and heat being again gradually applied, the whole is to be stirred until it acquires the proper consistence, as before.

3. Blanched sweet almonds and white sugar, of each 1 lb.; blanched bitter almonds and powdered gum, of each 3 oz.; beat them, in the cold, to a perfectly smooth paste, with orange-flower water or rose water, q. s., so that it may be sufficiently stiff not to stick to the fingers, and then cut the mass into squares, as before. The above are eaten as confections.

=Paste, Ancho′vy.= _Prep._ Remove the larger bones from the fish, and then pound them to a smooth paste in a marble mortar, adding a little bay-salt and cayenne pepper at will; next rub the pulp through a fine hair sieve, and about 3-4ths fill the pots with it; lastly, cover the surface of each to the depth of about 1/8 inch with good butter in a melted state. It should be kept in a cool situation. Other fish pastes, as those of bloaters, lobsters, shrimps, caviare, &c., are made in a similar manner.

=Paste, Arsen′ical.= See CAUSTICS, PATENT MEDICINES, and POWDERS.

=Paste, Baudry’s.= See PASTE, PECTORAL (_below_).

=Paste, Bird.= See GERMAN PASTE.

=Paste, Black Currant.= As black currant lozenges, but simply cutting the mass into dice or square.

=Paste, Car′rageen.= _Prep._ From Irish moss, as the lichen paste of the P. Cod. (see _below_).

=Paste, Chinese′.= _Prep._ From bullock’s blood, 10 lbs., reduced to dryness by a gentle heat, then powdered, and mixed with quicklime, also in fine powder, 1 lb. It is used as a cement, made into a paste with water, and at once applied.

=Paste of Chlo′′ride of Zinc.= See CAUSTICS.

=Paste of Dates.= _Syn._ PASTA DACTYLIFERÆ, P. DACTYLORUM, L.; PÂTES DE DATTES, Fr. From dates (stoned), as jujube paste. Pectoral, and slightly astringent. Paste of gum Senegal is usually sold for it.

=Paste, De Handel’s.= _Prep._ From opium, 1/2 dr.; camphor, 1 dr. (both in powder); extracts of belladonna and henbane, of each 1 dr.; oil of cajeput and tincture of cantharides, of each 10 or 12 drops; distilled water of opium (or of lettuce), q. s. In toothache.

=Paste, Depil′atory.= _Syn._ PASTA EPILATORIA, L. Several preparations of this character are noticed at pages 552-3. 1. A mixture of slacked lime, 2 parts, and water, 3 parts, saturated with sulphuretted hydrogen, is said to be so powerful, that “a layer a line in thickness denudes the scalp in three minutes.” (Beasley.)

2. (Payan.) Powdered sulphate of copper made into a soft paste with yolk of egg.

=Paste of Figs.= _Syn._ PASTA CARICARUM, P. FICARIA, L. _Prep._ 1. From figs, as jujube paste.

2. (Soubeiran.) Pulp of figs, 1 part; press it through a sieve, mix it with powdered sugar, 4 parts, concentrated by a gentle heat (if necessary), roll the mass out, and cut it into squares or lozenges.

=Paste, Flour.= _Syn._ COLLE DE PÂTE, Fr. From wheaten flour. Paper-hangers, shoemakers, &c., usually add to the flour 1/6 to 1/4 of its weight of finely powdered resin. It is then sometimes called ‘hard paste.’ The addition of a few drops of creasote or oil of cloves, or a little powered camphor, colocynth, or corrosive sublimate (especially the first two and the last), will prevent insects from attacking it, and preserve it in covered vessels for years. Should it get too hard, it may be softened with water. See CEMENTS.

=Paste, Fruit.= _Prep._ 1. To each pint of the strained juice add of gum Arabic, 1 oz., gently evaporate to the consistence of a syrup, and add an equal weight of bruised white sugar; as soon as the whole is united, pour it out on an oiled slab, and, when cold enough, cut it into pieces.

2. Citric acid, 3/4 oz.; gum Arabic, 6 oz.; white sugar, 3/4 lb.; water, q. s.; dissolve, and flavour with any of the fruit essences. It may be coloured with any pf the stains used for confectionery or liqueurs.

3. As fruit lozenges.

=Paste, Fur′niture.= See POLISH.

=Paste, Glove.= See GANTEINE.

=Paste of Gum Arabic.= _Syn._ PASTA GUMMI, L.; PÂTE DE GOMME, P. DE G. ARABIQUE, Fr. _Prep._ 1. As marshmallow paste, omitting the mallow roots.

2. Gum Arabic (picked), 1 lb.; water, 1 pint; dissolve, add of white sugar, 1 lb.; evaporate by a gentle heat to a very thick syrup, then add the whites of 3 eggs, previously beaten up with orange-flower water, 1 fl. oz., and strained through muslin, and continue the heat with constant stirring, until of a proper consistence on being cooled. The last two are commonly sold for marshmallow paste (pâte de guimauve).

3. (Transparent.) From gum Arabic (picked), 1 lb.; cold water, 1 pint; white sugar, 1-1/4 lb.; proceed as the last, adding orange-flower water 1 fl. oz., towards the end. Often sold under the name of ‘white jujubes.’

=Paste of Gum Senegal.= _Syn._ PÂTE DE GOMME SENEGAL, Fr. As jujube paste, without the fruit.

=Paste, Hon′ey.= See PASTE, ALMOND.

=Paste, Ju′jube.= _Syn._ JUJUBES, JUJUBE LOZENGES; PASTA JUJUBÆ, L.; PÂTE DE JUJUBES, Fr. _Prep._ (P. Cod.) Jujubes (the fruit), 1 lb.; water, 4 lbs.; boil 1/2 hour, strain with expression, settle, decant the clear portion, and clarify it with white of egg; add a strained solution of gum Arabic, 6 lbs., in water, 8 lbs., and to the mixture add of white sugar, 5 lbs.; gently evaporate, at first constantly stirring, and afterwards without stirring, to the consistence of a soft extract, then add of orange-flower water, 6 fl. oz., and place the pan in a vessel of boiling water. In 12 hours carefully remove the scum, pour the matter into slightly oiled tin moulds, and finish the evaporation (hardening) in a stove heated to 104°, Fahr. It is commonly coloured with beet-root, cochineal, or saffron. Expectorant; in coughs, &c. Paste of gum Arabic is usually sold for it.

=Paste, Li′chen.= _Syn._ PASTA LICHENIS, L.; PÂTE DE LICHEN, Fr. _Prep._ (P. Cod.) Iceland moss, 1 lb.; water, q. s.; heat them to nearly the boiling-point, strain with pressure, reject the liquor, and boil the moss in fresh water, q. s., for 1 hour; strain, press, add of gum Arabic, 5 lbs.; white sugar, 4 lbs., and evaporate to a proper consistence, as above. Pectoral. With the addition of 1/2 gr. of extract of opium to each oz., it forms the opiated lichen paste. (P. Cod.)

=Paste, liquorice.= _Syn._ LIQUORICE JUJUBES; PASTA GLYCIRRHIZÆ, L.; PÂTE DE RÉGLISSE, P. DE R. NOIRE, Fr. _Prep._ 1. (P. Cod.) Refined juice and white sugar, of each 1 lb.; gum Arabic, 2 lbs.; water, 3 quarts; dissolve, strain, evaporate considerably, and, of finely powdered orris root, 1/2 oz.; oil of aniseed or essence of cedrat, a few drops, and pour the paste upon an oiled slab, or into moulds, as before.

2. (Brown; PÂSTA G. FUSCA; PÂTE DE R. BRUNE.) Refined juice, 4 oz.; white sugar, 2 lbs.; gum Arabic, 3 lbs.; water, 4 pints; proceed as last.

3. (Opiated; PÂTE DE R. OPIACE.——P Cod.) To the last add of extract of opium, 15 gr.

4. (White; PÂTE DE RÉGLISSE BLANCHE.) As No. 2, substituting the powder of the decorticated root for the extract. All the above are pectoral; the second is also slightly anodyne. They are useful in tickling coughs, hoarseness, &c.

=Paste, London.= _Syn._ PASTA LONDINENSIS. Equal parts of caustic soda and unslaked lime. Reduce to a fine powder in a warm mortar, and mix intimately. Keep it in well closed bottles, and when required for use take as much as is sufficient, and make it into a paste with water.

=Paste, Marsh-mallow.= _Syn._ PASTA ALTHÆÆ, L.; PÂTE DE GUIMAUVE, Fr. _Prep._ (P. Cod. 1816.) Decorticated marshmallow root (French), 4 oz.; water, 1/2 gall.; macerate for 12 hours, strain, add white sugar and gum Arabic, of each 2-1/2 lbs.; dissolve, strain, evaporate without boiling to the thickness of honey, constantly stirring, and add, gradually, the whites of 12 eggs, well beaten with orange-flower water, 4 fl. oz., and strained; continue the evaporation and constant stirring until the mass is so firm as not to adhere to the fingers, then proceed as before.

_Obs._ It should be very white, light, and spongy. In the P. Codex of 1839 the marshmallow root is omitted, and the name is changed to that of ‘pâte de gomme,’ a compound long sold for it in the shops. Both are agreeable pectorals. See PASTE OF GUM ARABIC.

=Paste, Odontal′gic.= _Syn._ PASTA ODONTALGICA, L. _Prep._ 1. Pellitory (in powder), 1 dr.; hydrochlorate of morphia, 3 gr.; triturate; add, of honey, 2 dr.; and oil of cloves, 6 drops.

2. Powdered mastic, pellitory, and white sugar, of each 1 dr.; chloroform, q. s. to form a paste. It must be kept in a stoppered bottle. See TOOTHACHE, and _below_.

=Paste, Or′ange.= _Prep._ From orange flowers, 2 lbs.; bitter and sweet almonds, of each blanched, 2-1/2 lbs.; beaten to a perfectly smooth paste. An agreeable cosmetic. See PASTE, ALMOND.

=Paste, Or′geat.= _Prep._ From blanched Jordan almonds, 1 lb.; blanched bitter a. and white sugar and honey, of each 1/4 lb.; beaten to a paste, with orange-flower water, q. s. (or neroli, a few drops), and put into pots. As a cosmetic or to make orgeat milk. For use, rub 1 oz. with 1/2 pint of water, and strain through muslin.

=Paste, Pec′toral.= _Syn._ PASTA PECTORALIS, L. _Prep._ 1. (PÂTE PECTORALE DE BAUDRY.) Take of gum Arabic and white sugar of each 7 lbs.; water, q. s.; dissolve, add of extract of liquorice, 3 oz.; evaporate, add of extract of lettuce, 2 dr.; balsam of tolu, 1-1/4 oz.; orange-flower water, 4-1/2 fl. oz.; white of 4 eggs; oil of citrons, 5 or 6 drops.

2. (PÂTE PECTORALE BALSAMIQUE DE REGNAULT.) From the flowers of coltsfoot, cudweed, marrow, and red poppy, of each, 1 oz.; water, 1 quart; boil, strain; add, of gum Arabic, 30 oz.; white sugar, 20 oz.; dissolve, concentrate, add of tincture of tolu, 3 fl. dr., and pour the mixture on an oiled slab.

3. (ANISATED COLTSFOOT PASTE; PÂTE DE TUSSILAGE À L’ANIS.) From a strong decoction of coltsfoot flowers, 1 quart; Spanish juice, 1/2 lb.; dissolve, strain, evaporate as before, and towards the end add of oil of aniseed, 1 dr. All the above are useful in hoarseness, coughs, &c.

=Paste, Pho′sphor.= See RATS.

=Paste, Pol′ishing.= _Prep._ 1. (For copper and brass.) See BRASS PASTE.

2. (For iron and steel.) From emery (in fine powder) and lard, equal parts.

3. (For pewter.) From powdered Bath brick, 2 parts; soft soap, 1 part; water, q. s. to make a paste. Used with a little water, and afterwards well rinsed off.

4. (For furniture.) See POLISH.

=Paste, Ra′′zor.= _Prep._ 1. From jeweller’s rouge, plumbago, and suet, equal parts, melted together and stirred until cold.

2. From prepared putty powder (levigated oxide of tin), 3 parts; lard, 2 parts; crocus martis, 1 part; triturated together.

3. Prepared putty powder, 1 oz.; powdered oxalic acid, 1/4 oz.; powdered gum, 20 grs.; make a stiff paste with water, q. s., and evenly and thinly spread it over the strop, the other side of which should be covered with any of the common greasy mixtures. With very little friction this paste gives a fine edge to the razor, and its action is still further increased by slightly moistening it, or even breathing on it. Immediately after its use, the razor should receive a few turns on the other side of the strop.

4. Diamond dust, jeweller’s rouge, and plumbago, of each 1 part; suet, 2 parts. Powdered quartz is generally substituted for diamond dust, but is much less effective.

5. (Mechi’s.) Emery (reduced to an impalpable powder), 4 parts; deer suet, 1 part; well mixed together.

6. (Pradier’s.) From powdered Turkey stone, 4 oz.; jeweller’s rouge and prepared putty powder, of each 1 oz.; hard suet, 2 oz.

_Obs._ The above (generally made up into square cakes) are rubbed over the razor strop, and the surface being smoothed off with the flat part of a knife or a phial bottle, the strop is set aside for a few hours to harden before being used.

=Paste, Regnault’s.= See PASTE, PECTORAL.

=Paste, Rubefa′′cient.= _Syn._ PASTA RUBEFACIENS, L. _Prep._ (Clarus.) From acetate of lead, 1 oz.; bisulphite of potassa, 3 oz.; water, q. s. It acts powerfully and quickly on the skin.

=Paste, Rust’s.= _Prep._ From powdered opium and extract of henbane, of each 10 gr.; powdered pellitory and extract of belladonna, of each 20 gr.; oil of cloves, 10 drops. In toothache.

=Paste, Sha′′ving.= _Prep._ 1. Naples soap (genuine), 4 oz.; powdered Castile soap, 2 oz.; honey, 1 oz.; essence of ambergris and oils of cassia and nutmegs, of each 5 or 6 drops.

2. White wax, spermaceti, and almond oil, of each 1/4 oz.; melt, and, whilst warm, beat in 2 squares of Windsor soap previously reduced to a paste with a little rose water.

3. White soft soap, 4 oz.; spermaceti and salad oil, of each 1/2 oz.; melt them together, and stir until nearly cold. It may be scented at will. When properly prepared, these pastes produce a good lather with either hot or cold water, which does not dry on the face. The proper method of using them is to smear a minute quantity over the beard, and then to apply the wetted shaving-brush, and not to pour water on them, as is the common practice.

=Paste, Styptic, of Gutta Percha.= _Syn._ PASTA GUTTÆ PERCHÆ STYPTICA. (Mr Beardsley.) Gutta percha, 1 oz.; Stockholm tar, 1-1/2 or 2 oz.; creosote, 1 dr.; shellac, 1 oz., or q. s. to render it sufficiently hard. To be boiled together with constant stirring, till it forms a homogeneous mass.

For alveolar hæmorrhage, and as a stopping for teeth in toothache. To be softened by moulding with the fingers.

=Paste, Swediaur.= See CHILBLAIN.

=Paste, Tooth.= _Syn._ PASTA DENTIFRICIA, ELECTUARIUM DENTIFRICUM, L. Various preparations are known under this name. They consist, for the most part, of the ordinary substances used as dentifrices, reduced to the state of a very fine powder, and mixed with sufficient honey, sugar, or capillaire, to give them the required consistence. Honey of roses is often used for this purpose, with some agreeable perfume at will. A little eau de Cologne or rectified spirit is a useful addition. The following are a few examples:——

1. (CARBON PASTE; OPIAT CARBONIQUE.) The chippings of Turkey stone, cylinder charcoal, and prepared chalk, of each 2 oz.; cochineal and cloves, of each 1 dr.; honey, 5 oz.; eau de Cologne, q. s. It should not be put into the pots until the next day, and should be afterwards well preserved from the air. Much prized by smokers, and by persons troubled with a fetid breath from rotten teeth.

2. (CORAL PASTE; OPIAT DENTIFRICE ROUGE.) From prepared coral, 8 oz.; cuttle-fish bone, 4 oz.; mastic, 2 oz.; cochineal, 1/4 oz.; honey, 3/4 lb.; essence of ambergris, 1 fl dr.; oil of cloves, 1/2 fl. dr., dissolved in rectified spirit, 1 fl. oz. As the last. Cleanse the teeth rapidly.

3. (Dyon’s CHARCOAL PASTE.) From chlorate of potassa, 1 dr.; mint water, 1 fl. oz.; triturate until dissolved, then add, of powdered charcoal, 2 oz.; honey, 1 oz.

4. (MAGIC PASTE.) From white marble dust 4 oz.; pumice stone (in impalpable powder), 3 oz.; rose pink, 1 oz.; honey, 1/2 lb.; otto of roses, 15 drops. Rapidly whitens the teeth, but it should not be used too freely, nor too frequently.

5. (P. Cod.) Prepared coral, 4 oz.; bitartrate of potassa, 2 oz.; cuttle-fish bone and cochineal, of each 1 oz.; alum, 1/2 dr.; Narbonne honey, 10 oz.; with essential oil, q. s. to aromatise the mixture.

6. (Pelletier’s ODONTINE.) This is stated to be a mixture of pulverised sepia-bone, butter of cacao, and honey, with essential oil.

7. (ROSE PASTE.) Coral paste scented with roses, or the following:——Cuttle-fish bone, 1 oz.; prepared chalk, 2 oz.; cochineal, 1/2 dr.; honey of roses, 3 oz.; otto of roses, 6 drops.

8. (SOLUBLE PASTE, SALINE DENTIFRICE.) From bitartrate of potassa or sulphate of potassa (in fine powder), 3 oz.; honey of roses, 2 oz.

9. (SPANISH DENTIFRICE, CASTILIAN TOOTH CREAM.) From Castile soap (in fine powder) and cuttle-fish bone, of each 2 oz.; honey of roses, 5 oz. An excellent preparation. It is superior to all the other pastes for removing tartar and animalculæ from the teeth.

10. (VANILLA PASTE.) From red cinchona bark, 2 dr.; vanilla, 1 dr.; cloves, 1/2 dr. (the last two reduced to powder by trituration with); white sugar, 1 oz.; cuttle-fish bone and marble dust, of each 1/2 oz.; syrup of saffron, q. s.

11. (VIOLET PASTE.) From prepared chalk and cuttle-fish bone of each 3 oz.; powdered white sugar, 2 oz.; orris root 1 oz.; smalts, 1/4 oz.; syrup of violets, q. s. to mix.

12. (Winckler’s ROSEATE DENTIFRICE.) From cuttle-fish bone, 1 part; conserve of roses (Ph. L.), 3 parts; white otto of roses, 2 drops to the oz.

13. Chalk, 8 oz.; myrrh and rhatany root, of each 2 oz.; orris root, 1 oz.; honey of roses, q. s. to mix. In foul and spongy gums.

=Paste, Tooth′ache.= See PASTE, ODONTALGIA.

=Paste, Tor′mentil.= _Syn._ PASTA TORMENTILLÆ, L. _Prep._ (Morin.) Powdered tormentil root made into a paste with white of egg. In whitlow; applied on linen. Mixed with an equal weight of simple syrup, it has also been recommended in dysentery and diarrhœa.

=Paste, Vienna.= See CAUSTIC POTASSA WITH LIME.

=Paste, Vohler’s.= _Prep._ From dragon’s blood, 1 dr.; powdered opium, 2 dr.; powdered gums of mastic and sandarach, of each 4 dr.; oil of rosemary, 20 drops; tincture of opium, q. s. to form a paste. In toothache.

=Paste, Ward’s.= See CONFECTION OF PEPPER.

=PASTES.= _Syn._ ARTIFICIAL GEMS, FACTITIOUS G.; PIERRES PRÉCIEUSES ARTIFICIELLES, Fr. Vitreous compounds made in imitation of the gems and precious stones. The substances which enter into their composition, and the principles on which their successful production depends, have been already briefly noticed. The present article will, therefore, be confined to giving the reader a few original formulæ, together with several others carefully selected from the most reliable English and Continental authorities. Like enamels the artificial gems have for their basis a very fusible, highly transparent and brilliant, dense glass, which is known under the name of ‘frit,’ ‘paste,’ ‘strass,’ ‘flux,’ ‘fondant,’ or ‘Mayence base,’ and which in its state of greatest excellence constitutes the ‘artificial diamond.’ For convenience, this will be noticed here under its last synonym. (See _below_, also Ure’s ‘Dictionary of Arts,’ &c.)

=Amethyst.= 1. Paste or strass, 500 gr.; oxide of manganese, 3 gr.; oxide of cobalt, 24 gr.

2. (Douault-Wiéland.) Strass, 4608 gr.; oxide of manganese, 36 gr.; oxide of cobalt, 2 gr.

3. (Lançon.) Strass, 9216 gr.; oxide of manganese, 15 to 24 gr.; oxide of cobalt, 1 gr.

=Aqua Marina.= From strass, 4800 gr.; glass of antimony, 30 gr.; oxide of cobalt, 1-1/2 gr. See BERYL, of which this is merely a variety.

=Aventurine.= 1. From strass, 500 gr.; scales of iron, 100 gr.; black oxide of copper, 50 gr.; fuse until the black oxide of copper is reduced to the reguline form, then allow the mass to cool very slowly, so that the minute crystals of metal may be equally diffused through it. Has a rich golden iridescence.

2. As the last, but submitting oxide of chromium for the protoxide of copper. Appears brown, filled with countless gold spangles; or, when mixed with more paste, of a greenish grey, filled with green spangles.

=Beryl.= (Douault-Wiéland.) Strass, 3456 gr.; glass of antimony, 24 gr.; oxide of cobalt, 1-1/2 gr. See AQUA MARINA.

=Carbuncle.= See GARNET.

=Chrysolite.= From strass 7000 gr.; pure calcined sesquioxide of iron (‘trocus martis’), 65 gr.

=Cornelian.= 1. (RED.) From strass, 7000 gr.; glass of antimony, 3500 gr.; calcined peroxide of iron, 875 gr.; binoxide of manganese, 75 gr.

2. (WHITE.) From strass, 7200 gr.; calcined bones, 250 gr.; washed yellow ochre, 65 gr.

=Diamond.= 1. From rock crystal (purest), 1600 gr.; borax, 560 gr.; carbonate of lead (pure), 3200 gr.; oxide of manganese, 1/2 to 1 gr.; powder each separately, mix them together, fuse the mixture in a clean crucible, pour the melted mass into water, separate any reduced lead, and again powder and remelt the mass.

2. Pure silica, 150 gr.; pure litharge, 250 gr.; borax and nitre, of each 50 gr.; arsenious acid, 21 gr.

3. (Douault-Wiéland.)——_a._ From rock crystal, 4056 gr.; minium, 6300 gr.; potash, 2154 gr.; borax, 276 gr.; arsenic, 12 gr.

_b._ From rock crystal, 3600 gr.; ceruse of Clichy (pure carbonate of lead), 8508 gr.; potash, 1260 gr.; borax, 360 gr.

4. (Fontanier.) Pure silica, 8 oz.; salt of tartar, 24 oz.; mix, bake, cool, treat the fused mixture with dilute nitric acid until effervescence ceases, and afterwards with water as long as the washings affect litmus paper; next dry the powder, add to it of pure carbonate of lead, 12 oz. and to every 12 oz. of the mixture add of borax, 1 oz.; triturate in a porcelain mortar, melt in a clean crucible, and pour the fused mass into cold water; dry, powder, and repeat the process a second and a third time in a clean crucible, observing to separate any revived lead. To the third frit add of nitre, 5 dr., and again melt. The product is perfectly limpid and extremely brilliant.

5. (Lançon.) Litharge, 100 gr.; pure silica, 75 gr.; white tartar or potash, 10 gr.

6. (Loysel.) Pure silica, 100 parts; red oxide of lead (minium), 150 parts; calcined potash, 30 to 35 parts; calcined borax, 10 parts; arsenious acid, 1 part. This produces a paste which has great brilliancy and refractive and dispersive powers, and also a similar specific gravity to the oriental diamond. It fuses at a moderate heat, and acquires the greatest brilliancy when remelted, and kept for 2 or 3 days in a fused state, in order to expel the superabundant alkali, and perfect the refining (‘Polytech. Journ.’). The products of the above formulæ are not only employed to imitate the diamond, but they also form the basis of the other factitious gems. (See _above_.)

7. (YELLOW DIAMOND.) Strass, 500 gr.; glass of antimony, 10 gr.

=Eagle Marine.= From strass, 3840 gr.; copper stain, 72 gr.; pure zaffre, 1 gr.

=Emerald.= 1. From strass, 7000 gr.; carbonate of copper, 65 gr.; glass of antimony, 7 gr.

2. Paste, 960 gr.; glass of antimony, 42 gr.; oxide of cobalt, 3-1/2 gr.

3. (Douault-Wiéland) Paste, 4608 gr.; green oxide of copper, 42 gr.; oxide of chrome, 2 gr.

4. (Lançon.) Paste, 9612 gr.; acetate of copper, 72 gr.; peroxide of iron, 1-1/2 gr.

=Garnet.= 1. Paste or strass, 1200 gr.; glass of antimony, 580 gr.; purple of cassius and binoxide of manganese, of each 3 gr.

2. (Douault-Wiéland.) Paste, 513 gr.; glass of antimony, 256 gr.; purple of cassius and oxide of manganese, of each 2 gr.

3. (VINEGAR GARNET.) From paste, 7000 gr.; glass of antimony, 3460 gr.; calcined peroxide of iron, 56 gr.

=Lapis Lazuli.= From paste, 7000 gr.; calcined horn or bones, 570 gr.; oxides of cobalt and manganese, of each 24 gr. The golden veins are produced by painting them on the pieces with a mixture of gold powder, borax, and gum water, and then gently heating them until the borax fluxes.

=Opal.= 1. From strass, 960 gr.; calcined bones, 48 gr.

2. (Fontanier.) Paste, 1 oz.; horn silver, 10 gr.; calcined magnetic ore, 2 gr.; absorbent earth (calcined bones), 26 gr.

=Ruby.= 1. Paste, 45 parts; binoxide of manganese, 1 part.

2. Paste, 1 lb.; purple of cassius, 3 dr.

3. (Douault-Wiéland.)——_a._ From paste, 2880 parts; oxide of manganese, 72 parts.

_b._ Topaz-paste that has turned out opaque, 1 part; strass, 8 parts; fuse them together for 30 hours, cool, and again fuse it in small pieces before the blowpipe. Very fine.

4. (Fontanier.) Strass, 16 oz.; precipitate of cassius, peroxide of iron, golden sulphide of antimony, and manganese calcined with nitre, of each 168 gr.; rock crystal, 2 oz., or more.

5. Paste and glass of antimony, of each 8 oz.; rock crystal, 1 oz.; purple of cassius, 1-1/2 dr. Turns on the orange.

=Sapphire.= 1. From strass, 3600 gr.; oxide of cobalt, 50 gr.; oxide of manganese, 11 gr.

2. (Douault-Wiéland.) Paste, 4608 gr.; oxide of cobalt, 68 gr.; fuse in a little Hessian crucible for 30 hours.

3. (Fontanier.) Paste, 8 oz.; oxide of cobalt, 49 gr.

=Topaz.= 1. From strass, 1050 gr.; glass of antimony, 44 gr.; purple of cassius, 1 gr.

2. (Douault-Wiéland.) Paste, 3456 gr.; calcined peroxide of iron, 36 gr.

=Turquoise.= From blue paste, 20 to 24 parts; calcined bones, 1 part.

_Concluding remarks._ It is absolutely necessary for the successful application of the preceding formulæ that the substances employed should be perfectly free from impurities, more particularly those of a mineral kind. The litharge, oxide of lead, and carbonate of lead, above all things, must be entirely free from oxide of tin, as the smallest particle of that substance may impart a ‘milkiness’ to the paste. All the ingredients must be separately reduced to powder, and, after being mixed, sifted through lawn. The fusion must be carefully conducted and continuous, and the melted mass should be allowed to cool very slowly, after having been left in the fire from 24 to 30 hours, at the least. Hessian crucibles are preferred for this purpose, and the heat of an ordinary pottery or porcelain kiln is sufficient in most cases; but a small wind-furnace, devoted exclusively to the purpose, is, in general, more convenient. It is found that the more tranquil, continuous, and uniform the fusion, the denser and clearer is the paste, and the greater its refractive power and beauty.

All the coloured vitreous compounds noticed under GLASS may be worked up as ornamental stones, in the same way as those just referred to.

The following method of obtaining artificial rubies and emeralds, first pointed out by Boëttger, is exceedingly simple and inexpensive, and deserves the serious attention of those interested in this ingenious art:——Recently precipitated and well-washed hydrate of aluminum is moistened with a few drops of neutral chromate of potassium, and kneaded so that the mass assumes a tinge scarcely perceptible; it is then rolled up into small sticks, about the thickness of a finger, and slowly dried, taking the precaution to fill the fissures (if any) that form during desiccation with fresh hydrate of aluminum. When perfectly dry, and after having been submitted to a gentle heat, one end of these sticks is brought into the termination of the flame of an oxyhydrogen blowpipe, until a portion of the mass is fused into a small globule. After the lapse of a few minutes, several minute balls form, having a diameter of some millimètres, and of such intense hardness that quartz, glass, topaz and granite, may be easily and perceptibly scratched with them. These, when cut and polished, appear, however, slightly opaque. By employing nitrate of nickel in lieu of chromate of potassium, green-coloured globules, closely resembling the emerald, are obtained.

By the substitution of oxide of chromium for chromate of potassium, Mr Cooley produced factitious gems of considerable hardness and beauty, though slightly opaque in some portion of the mass. The addition of a very little silica prevented, in a great measure, this tendency to opacity.

It may be observed that the beauty of pastes of factitious gems, and especially the brilliancy of mock diamonds, is greatly depending upon the cutting, setting up, and the skilful arrangement of the foil or tinsel behind them. See ENAMEL, FOILS, GEMS, GLASS, &c.

=PAS′TELS.= [Fr.] Coloured crayons.

=PAS′TIL.= _Syn._ PASTILLE; PASTILLUS, PASTILLUM, L. A lozenge or confection. The pastilles (PASTILLI) of French pharmacy, are merely ‘confectionery drops’ aromatised or medicated. The name is also given to mixtures or odorous substances made up into small cones and burnt as incense. (See _below_).

=Pastils, Explo′sive.= Fumigating pastilles, containing a little gunpowder. Used to produce diversion, but they often prove far from harmless.

=Pastils, Fumiga′ting.= _Syn._ AROMATIC PASTILLES, INCENSE P.; PASTILLI FUMANTES, P. ODORATI, L. _Prep._ 1. Benzoin, 4 oz.; cascarilla, 1/2 oz.; nitre and gum Arabic, of each 3 dr.; myrrh, 1 dr.; oils of nutmeg and cloves, of each 25 drops; charcoal, 7 oz.; all in fine powder; beat them to a smooth ductile mass with cold water, q. s.; form it into small cones with a tripod base, and dry them in the air.

2. (Henry and Guibourt.) Powdered gum benzoin, 16 parts; balsam of tolu and powdered sandal wood, of each 4 parts; a light charcoal (Linden), 48 parts; powdered tragacanth and true labdanum, of each 1 part; powdered nitre and gum Arabic, of each 2 parts; cinnamon water, 12 parts; as above.

3. (P. Cod.) Benzoin, 2 oz.; balsam of tolu and yellow sandal wood, of each 4 dr.; nitre, 2 dr.; labdanum, 1 dr.; charcoal, 6 oz.; mix with a solution of gum tragacanth, and divide the mass into pastilles, as before.

4. (PASTILLES À LA FLEUR D’ORANGE.) For powdered roses in the next formula substitute pure orange powder, and for the essence of roses use pure neroli.

5. (PASTILLES À LA ROSE.) Gum benzoin, olibanum (in tears) and styrax (in tears), of each 12 oz.; nitre, 9 oz.; charcoal, 4 lbs.; powder of pale roses, 1 lb.; essence of roses, 1 oz.; mix with 2 oz. of gum tragacanth, dissolved in rose water, 1 quart.

6. (PASTILLES À LA VANILLE.) Gum benzoin, styrax, and olibanum (as last), of each 12 oz.; nitre, 10 oz.; cloves, 8 oz.; powdered vanilla, 1 lb.; charcoal, 4-1/2 lbs.; oil of cloves, 1/2 oz.; essence of vanilla, 7 or 8 fl. oz.; as before.

_Obs._ The products of the above formula are all of excellent quality. They may be varied to please the fancy of the artiste, by the addition or substitution of other perfumes or aromatics. Cheaper pastilles may be made by simply increasing the quantity of the charcoal and saltpetre. The whole of the ingredients should be reduced to fine powder before mixing them. The use of musk and civet, so often ordered in pastilles, should be avoided, as they yield a disagreeable odour when burned. The addition of a little camphor renders them more suitable for a sick chamber. The simplest and most convenient way of forming the mass into cones is by pressing it into a mould of lead or porcelain.

Pastilles are burned either to diffuse a pleasant odour, or to cover a disagreeable one. For this purpose they are kindled at the apex and set on an inverted saucer or a penny piece to burn. Persons who use them frequently employ a small china or porcelain toy (‘pastile house’) sold for the purpose.

=Pastils, Mouth.= _Syn._ BREATH PILL, CACHOU LOZENGES; PASTILLI COSMETICI, L.; CACHOU AROMATISÉ, C. AROMATIQUE, C. DE BOLOGNA, GRAINS DE CACHOU, Fr. _Prep._ 1. Soft extract of liquorice, 3 oz.; gum catechu and white sugar, of each 1 oz.; gum tragacanth (powdered), 1/2 oz.; oil of cloves, 1 dr.; oil of cassia, 1/2 dr.; essence of ambergris and oil of nutmeg, of each 12 drops; make a firm mass with rose or orange-flower water, q. s., and divide it into one-grain pills; when these are dry, cover them with gold or silver leaf.

2. Solazzi juice (dried by a gentle heat and powdered), 4 oz.; lump sugar, 3 oz.; powdered catechu, 2 oz.; powdered tragacanth, 1 oz.; oil of cloves, 2 fl. dr.; oil of cassia, 1 fl. dr.; white of egg or rose water, q. s. to form a pill-mass; as before.

3. Powdered catechu, 1 oz.; Solazzi juice, 4 oz.; lump sugar, 12 oz.; oils of cloves, cassia, and peppermint, of each 1 fl. dr.; mucilage of tragacanth, q. s. to mix; as before.

4. Extract of liquorice (soft), 2 oz.; white sugar, 3 oz.; powdered tragacanth and cascarilla (or orris root), of each 1/2 oz.; oil of cloves, 1/2 fl. dr.; oil of cassia, 12 drops, water, q. s.; as before.

5. (Chevallier.) Powdered coffee, chocolate and sugar, of each 1-1/2 oz.; powdered vanilla, and freshly burnt charcoal, of each 1 oz.; mucilage of tragacanth, q. s.

6. Chloride of lime (dry and good), 1 dr.; white sugar, 3 oz.; powdered tragacanth, 1 oz.; oil of cloves, 30 drops; rose water, q. s. To disinfect the breath.

_Obs._ Almost every maker employs his own forms for these articles. The objects to be aimed at are the possession of rather powerful and persistent odour, and a toughness to prevent their too rapid solution in the mouth. The original Italian formula included liquorice, mastic, cascarilla, charcoal orris root, oil of peppermint, and the tinctures of ambergris and musk, but is now seldom employed in this country. The flavour of peppermint does not, indeed, appear to be approved of by English smokers. Sometimes, instead of being made perfectly spherical, they are flattened a little.

CACHOU À L’AMBRE GRIS, CACHOU À LA CANELLE, CACHOU À LA FLEUR D’ORANGE, CACHOU MUSQUÉ, CACHOU À LA ROSE, CACHOU À LA VANILLE, CACHOU À LA VIOLETTE, &c., are merely flavoured and scented respectively with the essences or oils of ambergris, cinnamon, neroli, musk, rose vanilla, violets, &c. See BREATH, CACHOU AROMATISÉ, LOZENGES, PILLS, &c.

=PA′′STRY.= Articles of food made of ‘paste’ or dough, or of which ‘paste’ forms a principal and characteristic ingredient. The word is popularly restricted to those which contain puff paste, or such as form the staple production of the modern pastrycook; but it is, in reality, of much more general signification.

Several varieties of paste are prepared for different purposes, of which the following are the principal:——

PUFF PASTE. The production of a first class puff paste is commonly regarded as a matter of considerable difficulty, but by the exercise of the proper precautions it is, on the contrary, an extremely simple affair. This paste, before being placed in the oven, consists of alternate laminæ of butter or fat and ordinary flour dough, the latter being, of course, the thicker of the two. During the process of baking, the elastic vapour disengaged, being in part restrained from flying off by the buttered surfaces of the dough, diffuses itself between these laminæ, and causes the mass to swell up, and to form an assemblage of thin membranes or flakes, each of which is more or less separated from the other. Individually, these flakes resemble those of an ordinary rich unleavened dough when baked; but, collectively, they form a very light crust, possessing an extremely inviting appearance and an agreeable flavour.

The precautions above referred to are——the use of perfectly dry flour, and its conversion into dough with a light hand, avoiding unnecessarily working it,——the use of butter free from water or buttermilk, and which has been reduced to precisely the same degree of plasticity as the dough between which it is to be rolled,——conducting the operation in a cool apartment, and, after the second or third folding of the dough, exposing it to a rather low temperature before proceeding further with the process; and, lastly,——baking the paste in a moderately smart but not too hot an oven. The following are examples:——

1. (Rich.) Take of flour, 1 lb.; butter, 1/4 lb.; cold spring water, q. s.; make a moderately soft flexible dough, then roll in (as described above) of dry fresh butter, 1/2 lb.

2. (Ordinary.) Take of flour, 1 lb.; cold water, q. s.; make a dough, and roll in, as before, of butter, 6 oz.

3. (Rundell.) Take 1/4 peck of flour, rub into it 1 lb. of butter, and make a ‘light paste’ with cold water, just stiff enough to work well; next lay it out about as thick as a crown-piece; put a layer of butter all over it, sprinkle on a little flour, double it up, and roll it out again; by repeating this with fresh layers of butter three or four times, or oftener, a very light paste will be formed. Bake it in a moderately quick oven.

4. (Soyer.) Put 1 lb. of flour upon your pastry slab, make a hole in the centre, into which put a teaspoonful of salt, mix it with cold water into a softish flexible paste with the right hand, dry it off a little with flour until you have well cleared the paste from the slab, but do not work it more than you can possibly help; let it remain for 2 or 3 minutes upon the slab, then take 1 lb. of fresh butter from which you have squeezed all the buttermilk in a cloth, and brought to the same consistency as the paste, upon which place it; press it out flat with the hand, then fold over the edges of the paste so as to hide the butter, and reduce it with the rolling-pin to the thickness of about 1/2 an inch, when it will be about two feet in length; fold over one third, over which again pass the rolling-pin; then fold over the other third, thus forming a square; place it with the ends top and bottom before you, shaking a little flour both under and over, and repeat the rolls and turns twice again as before; flour a ‘baking-sheet,’ upon which lay it, on ice, if handy, or otherwise, in some cool place, for about half an hour; then roll it twice more, turning it as before, and again place it upon ice or in the cold for 1/4 of an hour; next give it two more rolls, making seven in all, and it is ready for use. “You must continually add enough flour while rolling to prevent your paste sticking to the slab.”

HALF-PUFF PASTE. As the preceding, using only one half the quantity of butter, and giving the paste only 3 or 4 folds.

SHORT PASTE, SHORT CRUST.——1. Flour (dry and warm), 1 lb.; sugar, 3 oz.; butter, 1/4 lb.; 2 eggs; water, 1/2 pint; make a light dough. If one half of ‘Jones’s patent flour’ be used, no eggs will be required.

2. (Soyer.) Put on the ‘paste slab’ or ‘pie board’ 1 lb. of flour, 2 oz. of pounded sugar, 6 oz. of butter, 1 egg, 1/2 teaspoonful of salt, and 1/2 pint of water; mix the sugar and water well together, add them with the water by degrees to the flour, and form a paste, but firmer than puff paste.

PIE PASTE. That commonly used is ‘short paste,’ varied at will; but at good tables the upper crust of the pie is generally made of ‘puff paste,’ and the remainder of ‘short paste.’

PUDDING PASTE. This for baked puddings may resemble the last. For boiled puddings (or indeed for any), the paste may be either ordinary ‘short paste,’ or one made with 2 to 6 oz. of butter or lard, or 3 to 8 oz. of chopped beef suet, to each lb. of flour, with or without an egg, and a little sugar, according to the means of the parties. The first is most appropriate for those containing fresh fruit, and that with suet for meat puddings, and those containing dried fruit, as grocers currants, plums, &c. Milk or milk-and-water is often used instead of simple water to make the dough. Ginger, spices, savory herbs, &c., are common additions to the crusts of puddings. Where economy is an object, and especially among the lower classes, kitchen fat is frequently substituted for suet, and lard for butter. When ‘Jones’s patent flour’ is employed, an excellent plain pudding paste may be made by simply mixing it up with very cold water, and immediately putting it into the water, which should be boiling, and kept in that state until the pudding is dressed.

=PA′TENT MED′ICINES.= _Syn._ MEDICAMENTA ARCANA, L. The majority of the preparations noticed under this head are the nostrums popularly termed ‘quack medicines,’ and which are sold with a Government stamp attached to them. A few other secret or proprietary remedies are also, for convenience, included in the list. An alphabetical arrangement, based on the names of the reputed inventors or proprietors of the articles, has been adopted, as being the one best suited for easy reference. The composition of a number of them is given from careful personal inspection and analysis (by Mr Cooley), and that of the remainder on the authority of Gray, Griffith, Paris, Redwood, the members of the Philadelphia College of pharmacy, and other respectable writers. A variety of articles, not included in the following list, is noticed along with other preparations for the class to which they belong, or under the names of their proprietors. See BALSAM, CERATE, DROPS, ESSENCE, TINCTURE, OINTMENT, PILLS, &c.

=Abernethy’s Pills.= See ABERNETHY MEDICINES.

=Albinolo’s Ointment.= See HOLLOWAY’S OINTMENT (_below_).

=Ali Ahmed’s Treasures of the Desert.= There are three preparations included under this name:——

_a._ (ANTISEPTIC MALAGMA.) From lead plaster, 3 parts; gum, thus and salad oil, of each 2 parts; beeswax, 1 part; melted together by a gentle heat, and spread upon calico.

_b._ (PECTORAL, ANTIPHTHISIS, or COUGH PILLS.) From myrrh, 3-1/2 lbs.; squills and ipecacuanha, of each 1 lb. (all in powder); white soft soap, 10 oz.; oil of aniseed, 1-1/4 oz; treacle, q. s. to form a pill mass.

_c._ (SPHAIROPEPTIC or ANTIBILIOUS PILLS.) From aloes, 28 lbs.; colocynth pulp, 12 lbs.; rhubarb, 7 lbs.; myrrh and scammony, of each 3-1/2 lbs.; ipecacuanha, 3 lbs.; cardamom seeds, 2 lbs. (all in powder); soft soap, 9 lbs.; oil of juniper, 7 fl. oz.; treacle, q. s. This, as well as the last, is divided into 3-1/2 gr. pills, which are then covered with tin foil or silver leaf. An excellent aperient pill, no doubt, and one likely to prove useful in all those cases in which the administration of a mild diaphoretic and stomachic purge is indicated. Unlike many of the advertised nostrums of the day, there is nothing in their composition that can by any possibility, prove injurious; but beyond this they are destitute of virtue.

=Anderson’s Scot’s Pills.= See PILLS.

=Atkinson’s Infant Preservative.= From carbonate of magnesia, 6 dr.; white sugar, 2 oz.; oil of aniseed, 20 drops; spirit of sal volatile, 2-1/2 dr.; laudanum, 1 dr.; syrup of saffron, 1 oz.; caraway water to make up 1 pint.

=Balm of Rackasiri.= See BALSAM.

=Balsam of Life.= _Syn._ BAUME DE VIE, Fr. Several compound medicines of this name are noticed on page 261. The following are well-known nostrums:——

1. (Hoffman’s)——_a._ Of the oils of cinnamon, cloves, lemon, lavender, and nutmegs, and balsam of Peru, of each 2 dr.; essence of ambergris, oil of amber, and oil of rue, of each 1 dr.; cochineal, 12 gr.; strongest rectified spirit, 3-1/2 pints; mix.

_b._ (Ph. Dan. 1840.) Oils of cinnamon, cloves, lavender, and nutmegs, of each 20 gr.; purified oil of amber, 10 drops; balsam of Peru, 30 gr.; rectified spirit (tinged with alkanet root), 10 oz.

2. (Gabius’s.) Nearly similar to Hoffmann’s.

3. (Turlington’s.) Benzoin and liquid styrax, of each 12 oz.; balsam of tolu and extract of liquorice, of each 4 oz.; balsam of Peru, 2 oz.; aloes, myrrh, and angelica root, of each 1 oz.; highly rectified spirit of wine, 7 pints; digest, with frequent agitation for 10 days, and filter. Externally, the above are rubefacient and corroborant; internally, stimulant, cordial, and pectoral.

=Betton’s British Oil.= From oil of turpentine, 1 pint; Barbadoes tar, 1/2 lb.; oil of rosemary, 1 fl. oz.

=Blake’s Green-mountain Ointment.= We are told that the active ingredient in this compound is _Arnica montana_, with a basis of soap cerate. It is very useful as an external applications in several affections. The chief objection to its use is that it is a secret preparation.

=Blake’s Toothache Essence.= From alum, in fine powder, 1 dr.; sweet spirit of nitre, 5 dr.

=Boerhaave’s Odontalgic Essence.= From opium, 1/2 dr.; oil of cloves, 5 dr.; powdered camphor, 5 dr.; rectified spirit, 1-1/2 fl. oz.

=Bouchardat’s Tasteless Aperient.= From phosphate of soda, 3/4 oz., placed in a soda-water bottle, which is then filled up with carbonated water, at the bottling machine. For a dose.

=Brand’s Tooth Tincture.= From pellitory of Spain (bruised), 1 oz.; camphor, 3/4 oz.; opium, 1/4 oz.; oil of cloves, 1 dr.; digested for 10 days in rectified spirit, 1/2 pint.

=Brodum’s Nervous Cordial.= _Prep._ 1. “Originally it consisted simply of an infusion of gentian root in English gin, coloured and flavoured with a little red lavender (compound spirit of lavender.). After a time the doctor added a little bark to the nostrum, and subsequently made other additions.” (‘Anat. of Quackery,’)

2. (Paris.) Tinctures of gentian, calumba, cardamoms, and cinchona, compound spirits of lavender, and steel wine, of each equal parts. “It is tonic, stomachic, and stimulant; but, beyond these, possesses no curative properties.” ‘Anat. of Quackery.’

=Chlorodyne.= This nostrum, which was first introduced as “a combination of perchloric acid with a new alkaloid,” has become a popular anodyne and sedative. Several preparations are sold under this name, and the claims of the rival makers have occasioned some expensive lawsuits. The name was undoubtedly invented by Dr J. Collis Browne, but Mr Freeman, pharmaceutical chemist, claims to be the inventor of the preparation. Whether Browne’s and Freeman’s ‘chlorodynes’ are essentially the same, we are not able to determine, but we know that there is not the slightest foundation for the statements made by each manufacturer respecting the new vegetable principle contained in his medicine. Chlorodyne, in every one of its forms, is simply a mixture of certain well-known materials, some of which are rather dangerous ingredients for a popular nostrum. According to the analysis of Dr Odgen, Browne’s chlorodyne is composed as follows:——

Chloroform, 6 dr.; chloric ether, 1 dr.; tincture of capsicum, 1/2 dr.; oil of peppermint, 2 drops; hydrochlorate of morphine, 8 gr.; Scheele’s hydrocyanic acid, 12 drops; perchloric acid, 20 drops; tincture of Indian hemp, 1 dr.; treacle, 1 dr. ‘Towle’s chlorodyne’ is prepared according to this formula, the ingredients being named on the label.

=Clarke’s Conglutinum.= See CONGLUTINUM.

=Cochrane’s Cough Remedy.= Acidulated syrup of poppies.

=Corn Nostrums.= See CORN.

=Cottereau’s Odontalgic Essence.= A nearly saturated ethereal solution of camphor, mixed with about 1/12th of its volume of strong liquor of ammonia.

=Curtis’s Anti-venereal Lotion.= A mixture of Beaufoy’s solution of chloride of lime, 2 fl. oz., with cold soft water, 8 fl. oz. For use, 1 to 2 table-spoonfuls are put into a wine-glassful of water.

=Dalby’s Carminative.= 1. (Dr Paris.) Carbonate of magnesia, 40 gr.; tincture of castor and compound tincture of cardamoms, of each 30 drops; tincture of assafœtida, and spirit of pennyroyal, of each 15 drops; laudanum, 5 drops; oil of aniseed, 3 drops; oil of nutmeg, 2 drops; oil of peppermint, 1 drop; peppermint water, 2 fl. oz.——_Dose_, 1/2 to 1 teaspoonful. The bottle should be well shaken before pouring it out.

2. (Wholesale.) Carbonate of magnesia, 1 oz.; tincture of castor, 5 fl. dr.; tincture of assafœtida, 3 fl. dr.; oils of aniseed and pennyroyal, of each 1/4 fl. dr.; oil of nutmeg, 15 drops; syrup of poppies, 7 oz.; rectified spirit. 3-1/2 fl. oz.; peppermint water, 1/2 pint; as before.

=Davidson’s Cancer Remedy.= A mixture of arsenious acid and hemlock, both in powder. (Dr Paris.)

=Davis’s Calorific.= The ‘LIQUID’ is commercial acetic acid (sp. gr. 1·048), dilated with about an equal volume of water, and coloured with burnt sugar or spirit colouring. The ‘SHIELD’ consists of a piece of red flannel backed with oil skin, to prevent evaporation. A few drops of calorific are sprinkled on the flannel, which is then bound over the affected part. The heat of the body gradually volatilises the acetic acid, and the escape of the vapour being prevented by the oil skin, a strongly counter-irritant action is set up.

=Derbyshire’s Embrocation.= From opium and mottled soap, of each 2 oz.; extract of henbane, 2 dr.; and mace, 1/2 dr.; boiled for 30 minutes, in water, 3 pints; to the cold liquor, rectified spirit, 1 quart, and liquor of ammonia, 1 fl. oz., are added, and, after repose, the clear portion is decanted. A preventive of sea-sickness.

=Deshler’s Cerate.= Yellow basilicon.

=Duncan’s Gout Medicine.= See GOUT.

=Dutch Ague Remedy.= A mixture formed of Peruvian bark and cream of tartar, of each 1 oz.; cloves, 1/2 dr.; reduced to fine powder.——_Dose_, 1-1/2 dr., every 3 hours. (Dr Paris.)

=Godfrey’s Cordial.= 1. (Original formula.) Opium (sliced), 1/4 oz.; sassafras chips 1 oz.; English brandy, 1 quart; macerate for 4 or 5 days, then add, of water, 1 quart, treacle, 3-1/2 lbs., and simmer the whole gently for a few minutes; the next day decant the clear portion.

2. (Dr Paris.) Aniseed, caraways, and corianders, of each, bruised, 1 oz.; sassafras chips, 9 oz.; water, 6 pints; simmer gently until reduced to 4 pints, then add of treacle, 6 lbs.; and when nearly cold, further add of tincture of opium, 3 fl. oz.

3. (Phil. Coll. of Phar.) Carbonate of potassa, 2-1/2 oz.; water, 26 pints (old wine measure); dissolve, add of sugar-house molasses (treacle), 16 pints (o. w. m.); simmer the mixture, remove the scum, and when it has considerably cooled, add of tincture of opium, 24 fl. oz.; oil of sassafras, 1/2 fl. oz.; (dissolved in) rectified spirit, 1 quart (o. w. m.) It contains about 16 drops of laudanum (= 1-1/8 gr. of opium) in each fl. oz.

The following forms are also current in the wholesale trade:——

4. From molasses, 16 lbs.; distilled water, 2-3/4 galls.; oil of sassafras, 1 fl. oz.; (dissolved in) rectified spirit, 1/2 gall.; bruised ginger, 3/4 oz.; cloves, 1/2 oz.; laudanum, 8 fl. oz.; macerate for 14 days, and strain through flannel.

5. Sassafras chips, 1 lb.; ginger (bruised), 4 oz.; water, 3 galls.; simmer until reduced to 2 galls.; then add of treacle, 16 lbs.; rectified spirit, 7 lbs.; laudanum, 1 pint.

6. Opium, 1/2 oz.; treacle, 7 lbs.; boiling water, 1 gall.; dissolve, and add, of rectified spirit, 1 quart; oil of sassafrass, 1/2 dr.; cloves and mustard seed, of each 1/4 oz.; coriander and caraway seeds, of each 1 dr.; digest for a week.

7. Caraways, corianders, and aniseed, of each 1 lb.; water, 6 galls.; distil 5 galls., and add, of treacle, 23 lbs.; laudanum, 1 quart; and oil of sassafras, 1 fl. oz., previously dissolved in rectified spirit, 1 gall.

_Obs._ This preparation is anodyne and narcotic, and, amongst the lower classes, is commonly given to children troubled with wind or colic. Its frequent and excessive use has sent many infants prematurely to the grave. Gray says, “It is chiefly used to prevent the crying of children in pain or starving.” The dose is 1/3 teaspoonful and upwards, according to the age and susceptibility of the child.

=Grave’s Gout Preventive.= A tincture prepared by steeping, for a week, dried orange peel and hiera picra, of each 1 oz., and rhubarb, 1/2 oz., in brandy, 1 pint.

=Grinrod’s Remedy for Spasms.= From acetate of morphia, 1 gr.; spirit of sal volatile and sulphuric ether, of each 1 fl. oz.; camphor julep, 4 fl. oz.; for a mixture. It should be kept closely corked, in a cool place, and should be well shaken before use.——_Dose._ A teaspoonful in a glass of cold water or wine, as required. It is a really valuable preparation.

=Herrenschwand’s Specific.= A mixture of gamboge, 10 gr., with carbonate of potassa, 20 gr. (Dr Paris.)

=Holloway’s Ointment.= The original formula of ALBINOLO’S OINTMENT, of which this pretends to be a reproduction, contained the “graisses der serpent et de vipère,” and other pharmaceutical curiosities. The principal ingredients, however, in the HOLLOWAY’S OINTMENT of the present day are very homely substances. In the case of Sillen _v._ Holloway, tried at the Court of Common Pleas in January, 1863, the plaintiff’s counsel asserted that, on the ointment being received by the agent in Paris, it was submitted to the authorised government chemists to be analysed, in accordance with the laws of France prohibiting the sale of secret remedies, and was found by them to contain butter, lard, Venice turpentine, white wax, yellow wax, and nothing else. In a letter to the ‘Times’ Mr Holloway stated that the French analysis was incorrect, for three of the ingredients named were not in the ointment, while there were other components which the analysts had not discovered. The formula adopted by those who prepare an imitation ointment on the large scale, and which closely resembles, if it be not actually identical with, that employed by Mr Holloway, is as follows:——Fresh butter (free from water), 3/4 lb.; beeswax (good), 4 oz.; yellow resin, 3 oz.; melt them together, add of vinegar of cantharides, 1 fl. oz., and simmer the whole, with constant agitation, for 10 or 12 minutes, or until the moisture is nearly evaporated; then add of Canada balsam, 1 oz.; expressed oil of mace, 1/2 dr.; balsam of Peru or liquid styrax, 10 or 12 drops; again stir well, allow the mixture to settle, and when it is about half cold (not before) pour it into the pots, previously slightly warmed, and allow it to cool very slowly. The label will do the rest. No two samples of Holloway’s ointment are precisely of the same colour or consistence.

=Holloway’s Pills.= From aloes, 4 parts; jalap, ginger, and myrrh, of each 2 parts; made into a mass with mucilage, and divided into 2-grain pills, of which about 4 dozen are put into each 1s. 1-1/2d. box.

=Jackson’s Bathing Spirit.= A species of soap liniment, made of soft soap, 1 lb.; camphor, 6 oz.; oils of rosemary and thyme, of each 3/4 fl. oz.; rectified spirit, 1 gall.

=Kaye’s Infant’s Preservative.= A preparation partaking of the joint properties of Atkinson’s nostrum and Godfrey’s cordial, but more powerful than either, as indicated by the doses in which it is directed to be given during early infancy, viz. “two, three, or more drops.”

=Keating’s Cough Lozenges.= These are said to be composed of——Lactucarium, 2 dr.; ipecacuanha, 1 dr.; squills, 3/4 dr.; extract of liquorice, 2 oz.; sugar, 6 oz.; made into a mass with mucilage of tragacanth, and divided into 20-gr. lozenges.

=King’s Sarsaparilla Pills.= From the compound extract. “Instead of two pills being equivalent to 1/2 fl. oz. of the concentrated decoction or essence of sarsaparilla, as asserted, it takes about 32 of them to represent the given quantity, and about 4 of them to be equal in strength to the common decoction of the Pharmacopœia.” “Instead of one 2s. 9d. box of these pills being equal to a pint of the costly concentrated fluid preparation, it would take nearly 1-1/2 lb. of them for that purpose.” (‘Med. Circ.,’ ii, 493.)

=Kitchener’s Peristaltic Persuaders.= See PILLS.

=Lambert’s Asthmatic Balsam.= The active ingredients in this compound are said to be squills and aqueous extract of opium.

=Lemazurier’s Odontalgic Essence.= From acetate of morphia, 1 gr.; dissolved in cherry-laurel water, 1 oz. For use, a teaspoonful is added to half a wine-glassful of warm water, and the mouth well rinsed out with the mixture.

=Leroy’s Purgative.=——_a._ (No. 1.) Vegetable turbith, 6 dr.; scammony, 1-1/2 oz.; jalap, 6 oz.; brandy, 10 pints; digest for 24 hours, and add a syrup made of senna, 6 oz.; water, 1-1/4 pint; sugar, 32 oz.

_b._ (No. 2.) As the last, only one third stronger.

_c._ (No. 3.) Twice as strong as No. 1.

=Lewis’s Electuarium.= A liquid nostrum, said to be alterative and to contain a small quantity of both antimony and mercury.

=Lewis’s Balsamic Ointment.= This preparation, which is declared by its proprietor to be “utterly unsurpassable,” for the most part resemble Holloway’s ointment. (‘Med. Circ.’ ii, 493.)

=Lewis’s Silver Cream.= This nostrum is said to depend for its efficacy on white precipitate and a salt of lead.

=Locock’s Pulmonic Lozenges.= See WAFERS.

=Mahomed’s Paste.= See ELECTUARY.

=Mardant’s Norton’s Drops.= A mixture of the tinctures of gentian and ginger, holding in solution a little bichloride of mercury, and coloured with cochineal.

=Marriott’s Dry Vomit.= A mixture of equal parts of tartar emetic and sulphate of copper.

=Marsden’s Drops.= A coloured solution of corrosive sublimate. (Dr Paris.)

=Matthieu’s Vermifuge.=——_a._ (To destroy the worms.) Tin filings, 1 oz.; male fern root, 6 dr.; worm seed, 4 dr.; resinous extract of jalap and sulphate of potassa, of each 1 dr.; honey, q. s. to form an electuary.——_Dose._ A teaspoonful, repeated every third or fourth hour for 2 or 3 days, when the following is to be substituted, and continued until the bowels are well acted on.

_b._ (To expel the worms.) Jalap and sulphate of potassa, of each 40 gr.; scammony, 20 gr.; gamboge, 10 gr.; honey, q. s. as before.

=McKinsey’s Golden Cerate.= This appears to resemble Poor Man’s Friend.

=McKinsey’s Katapotia.= This notorious nostrum is compounded of aloes, 5 oz.; soap, 1-1/2 oz. (both in powder); beaten up with syrup of saffron and a little essential oil, and divided into pills varying in weight from 2 to 2-1/2 gr. each. (‘Med. Circ.,’ iv, 86).

=McKinsey’s Medicinal Powder.= _Syn._ REV. T. SMITH’S M. P. From dried lavender flowers and rosemary tops, of each 2-1/2 oz.; asarabacca, 1 oz.; reduced to powder, and further disguised with a little perfume. A very small quantity of subsulphate of mercury is also most probably added. Two or three pinches of this powder, taken 3 or 4 times a day as snuff, is said by the proprietor to be sufficient to cure almost every known disease. See ASARABACCA.

=Morison’s Aperient Powder.= A mixture of cream of tartar and lump sugar, in nearly equal proportions, with sufficient powdered cassia to give it an aromatic flavour. See PILLS.

=Morison’s Adhesive Paste.= See PLASTER.

=Ollivier’s Biscuits.= Take of the white of 2 eggs; water, 3/4 pint; beat them together, strain the mixture, and add to it a solution of bichloride of mercury, 76 gr.; collect the precipitate, wash, dry, powder, and carefully weigh it; next add to it such a quantity of flour, &c., that each 2-dr. biscuit may contain exactly 1/7 gr.

=Papier Fayard.= See PAPER (Gout).

=Pate Arsenicale.= A powder composed of arsenious acid, 8 gr.; dragon’s blood, 22 gr.; cinnabar, 70 gr. It is to be made into a paste with the saliva at the time of applying it. A favourite remedy in cancer on the Continent. (Dr Paris).

=Perry’s Balm of Syriacum.= From English gin, 1 pint; moist sugar, 1/2 lb.; (dissolved in) water, 4 oz.; mix, and add of paregoric (Tinct. Camph. Co.——Ph. L. 1836), 1 oz.; tincture of tolu, 1/2 oz.; tincture of cantharides, q. s.; together with a few drops each of the oils of aniseed and spearmint; agitate well together, and the next day filter, or decant the clear portion.

=Perry’s Preventive Lotion.= This is said to be a solution of sal alembroth, 2 dr., in water, 1 pint. For use, it is diluted with 4 or 5 times its bulk of water.

=Pieste’s Toothache Essence.= From liquor of ammonia, 2 parts; laudanum, 1 part. It is applied on lint.

=Pilules Angéliques.= _Syn._ GRAINS DE SANTÉ. Take of aloes and juice of roses, of each 4 oz.; juices of borage and chicory, of each 2 oz.; beat them together, and when they are reduced to the consistence of a soft pill-mass, add of powdered rhubarb, 2 dr., powdered agaric, 1 dr., and divide the mixture into 1-1/2-gr. pills. A good purgative.——_Dose_, 4 to 12.

=Poor Man’s Friend.= (French.) See OINTMENT (Brown).

=Poor Man’s Friend.= (Dr Roberts’.) This consists chiefly of ointment of nitric-oxide of mercury.

=Pringle’s Remedy for Typhus.= (Dr Paris.) Pale cinchona (bruised), 1/2 oz.; water, 12 fl. oz.; boil them together for 10 minutes, adding, towards the end, Virginian snake-root (bruised), 2 dr.; macerate for an hour in a covered vessel, and to the strained liquid add of dilute sulphuric acid, 2 fl. dr., and when the mixture is cold, further add of spirit of cinnamon, 1 fl. oz. The dose is 2 table-spoonfuls every six hours.

=Reynolds’ Gout Specific.= Wine of colchicum disguised by some unimportant additions.

=Righini’s Odontalgic Drops.= A solution of creasote in an equal weight of the strongest rectified spirit, coloured with cochineal, and disguised by the addition of a few drops of oil of peppermint.

=Ruspini’s Styptic.= A strong solution of gallic acid in spirit of roses. Dr A. T. Thomson says that it also contains sulphate of zinc.

=Rust’s Toothache Paste.= See PASTE.

=Scott’s Drops.= _Syn._ TINCTURE OF SOOT. From wood-soot, 2 oz.; assafœtida, 1 oz.; brandy or proof spirit, 1 pint.——_Dose_, 1 to 2 table-spoonfuls; in hysteria, &c.

=Smith’s Powder.= See MCKINSEY’S POWDER.

=Solomon’s Anti-impetigines.= A solution of bichloride of mercury disguised by the addition of a little flavouring and tinctorial matter. (‘Med. Circ.,’ ii, 69, 70).

=Standert’s Red Mixture.= Take of carbonate of magnesia, 1 oz.; powdered Turkey rhubarb, 1/3 oz.; tincture of rhubarb, 3 fl. oz.; tincture of opium, 2 fl. dr.; oils of aniseed and peppermint of each 1/2 dr.; (dissolved in) gin or proof spirit, 5 fl. oz.; agitate the whole together, then further add of soft water, 1-1/4 pint. In colic and diarrhœa.——_Dose._ A wine-glassful. The spirit is frequently omitted, but then the mixture soon spoils.

=Standert’s Stomachic Candy.= Take of lump sugar, 1 lb.; water, 3 fl. oz.; dissolve by heat; add cardamom seeds, ginger, and rhubarb, of each 1 oz.; and when the mixture is complete, pour it out on an oiled slab or into moulds.

=Storey’s Worm Cakes.= Take of calomel and cinnabar, of each 24 gr.; powdered jalap, 72 gr.; ginger, 1 dr.; white sugar, 1-1/4 oz.; syrup, q. s.; mix and divide into a dozen cakes. Resemble ‘Ching’s lozenges’ in their action. (See page 1007).

=Struve’s Lotion.= See LOTION, HOOPING-COUGH.

=Succession Powder.= A mixture of powdered quartz and diamond dust, chiefly the first. Used as an escharotic.

=Tasteless Ague Drops.= A solution of arsenite of potassa. It is the common ague medicine in the fen counties of England.

=Turlington’s Balsam.= See BALSAM OF LIFE (_above_).

=Valangin’s Solution of Solvent Mineral.= From arsenious acid, 1/2 dr., dissolved in hydrochloric acid, 1-1/2 dr., and the solution diluted with distilled water, 1-1/2 pint. In ague, &c. It has rather less than half the strength of the solution of arsenite of potassa, Ph. L.

=Vance’s Cream.= See CHILBLAIN.

=Wahler’s Ointment.= See CHILBLAIN.

=Ward’s Purging Powder.= A mixture of jalap and cream of tartar, equal parts, coloured with a little red bole.——_Dose._ A teaspoonful, or more, in broth or beer, twice or thrice daily; in dropsy.

=Webster’s Diet Drink.= A sweetened decoction of betony, dulcamara, guaiacum wood, liquorice root, sarsaparilla, sassafras, thyme, and turmeric.

=Wilson’s Gout Tincture.= This is said to be wine of colchicum.

=Wright’s Pearl Ointment.= Take of white precipitate, 8 oz.; Goulard’s extract, 1 pint; rub them to a cream, and add the mixture to white wax, 7 lbs., and olive oil, 10 lbs., previously melted together by a gentle heat; lastly, stir the whole until it is nearly cold. (‘Pharm. Journ.’)

=Young’s Aperient Drink.= From carbonate of soda, 2-1/2 dr.; bitartrate of potassa, 3 dr. (both in crystals); throw them into a soda-water bottle containing cold water, 8 fl. oz., and immediately cork it down securely, and keep it inverted, in a cool place, until required for use.

=Zanhetti’s Bohemian Restorative Tincture.= From crushed raisins, 3/4 lb.; hay saffron, 2 oz.; aqueous extract of opium, 3 dr.; powdered cochineal, 2 dr.; capillaire and orange-flower water, of each 1/2 pint; proof spirit, 3 pints; digested together for a week, and then strained, with expression.

=PAULLIN′IA.= See GUARANA.

=PAYAN′IZING.= The name given to Mr Payne’s process for preserving and mineralising wood. See DRY-ROT.

=PEACH.= _Syn._ PERSICUM, L. The fruit of _Amygdalus Persica_. Two varieties are known in our gardens——CLINGSTONE PEACH and FREESTONE PEACH, terms which explain themselves. The fruit is wholesome; but the flowers and kernels contain prussic acid, and are poisonous.

The peach, the original habitats of which were Persia and the North of India, is now very generally grown in the South of Europe, in many parts of the East, and very largely in the more temperate portions of North and South America; more particularly in Pennsylvania, New Jersey, and Maryland, where there are extensive orchards of peach trees. This fruit is also extensively cultivated by the Mormon community at Utah. The fruit of the NECTARINE, which is a variety of the peach, differs from that of the latter in having a smooth skin. When stewed, the fruit of the peach is said to be useful in habitual constipation.

Dr Fresenius has analysed this fruit, and found its composition to be:——

_Soluble matter_—— Large Dutch. Sugar 1·580 Free acid (reduced to equivalent in malic acid) 0·612 Albuminous substances 0·463 Pectous substances 6·313 Ash 0·422

_Insoluble matter_—— Seeds 4·629 Skins } 0·991 Pectose } [Ash from soluble matter included in weights given] 0·042] Water 84·990 ———————— 100·000 ————————

It will be seen from the above that the peach contains a very small amount of sugar.

=PEACH′WOOD.= The produce of a species of _Cæsalpinia_, now extensively used in calico-printing.

=PEAR.= _Syn._ PYRUS, L. The fruit of _Pyrus communis_ (Linn.), one of the rosaceæ. Its general qualities resemble those of the apple.

COMPOSITION OF THE PEAR.

_Soluble matter_——

Sugar 7·000 Free acid (reduced to equivalent in malic acid) 0·074 Albuminous substances 0·260 Pectous substances, &c. 3·281 Ash 0·285

_Insoluble matter_——

Seeds 0·390 Skins 3·420 Pectose 1·340 [Ash from insoluble matter included in weights given] 0·050] Water 83·950 ———————— 100·000 (FRESENIUS.)

=PEARL.= _Syn._ MARGARITA, MARGARITUM PERLA, UNIO, L. The most beautiful and costly pearls are obtained exclusively from the pearl oyster (_Meleagrina margaritifera_) of the Indian Seas. The principal fisheries are on the coast of Ceylon, and at Olmutz, in the Persian Gulf. An inferior description of pearl is procured from a fresh-water shell-fish (_Unio margaritifera_) in the neighbourhood of Omagh, county of Tyrone. A similar quality is also procured from the river Ythan, Aberdeenshire. It is probable that pearls from this source collected by the ancient Britons may have given rise to the statement by Tacitus, in his ‘Life of Agricola,’ of pearls “not very orient, but pale and wan,” being among the indigenous products of Great Britain.

Pearls are composed of membrane and carbonate of calcium; or, in other words, of substances similar to bladder and chalk, in alternate layers.

The cause of the production of pearls is highly curious and interesting. When any foreign body gains a permanent lodgment within the shells of any of the mollusca which are lined with pearly matter, or nacre, the pearly secretion of the animal, instead of being spread in layers on the inside of its habitation, is accumulated around the offending particles in concentric films of extreme tenuity, and more or less spherical, forming a pearl.

Pearls were formerly used in medicine as absorbents or antacids; and among the ancients they were occasionally taken, dissolved in acid, both as a remedy and for the purpose of displaying the careless opulence and luxury of their possessors. A perfect pearl, large, truly spherical, highly iridescent, and reflecting and decomposing the rays of light with vivacity, claims to rank with the most costly of the gems, and in some parts of the East is, with justice, more highly prized than even the diamond. In Europe, however, the present estimation of their value is somewhat different, “A handsome necklace of Ceylon pearls, smaller than a large pea, costs from £170 to £300; but one of pearls about the size of peppercorns may be had for £15. The pearls in the former sell at a guinea each, and those in the latter at about 1s. 6d.” (Milburn.) Seed pearls are of little value, however beautiful.

=Pearl, Artificial.= These are hollow spheres or beads of glass, perforated with two holes at opposite sides to permit of their being strung into necklaces. A small portion of essence d’orient is introduced into each, by suction, and is then spread over the inner surface of the glass. When this has become dry and hard, the globe is filled up with white wax, spermaceti, or gum Arabic. The glass of which the beads are formed is slightly bluish and opalescent, and very thin. The latest improvement consists in removing the glassy appearance of the surface of the prepared bead by exposure to the fumes of hydrofluoric acid, highly diluted.

=Pearl, Mother of.= _Syn._ UNIONUM CONCHÆ, L.; NACRE DE PERLE, Fr. This is the internal or nacreous layer of those shells which produce the pearls for ornamenting the person; hence the term ‘mother of pearl’ is by no means inappropriate. It is also derived from several other species known in trade as ear-shells, green snail-shells, Bombay-shells, &c.

The brilliant hues of mother of pearl do not depend so much upon the nature of the substance as on its structure. Its surface is covered by minute corrugations or furrows, which give a chromatic appearance to the reflected light. Sir David Brewster was the first to show that this substance is capable of imparting its iridescent appearance to fusible metal or fine black wax.

Mother of pearl is cut and wrought with nearly similar tools to those used for ivory, but its treatment, owing to its more fragile nature and delicate structure, requires considerably greater care. It is polished with colcothar or putty powder.

The numerous applications of mother of pearl, for buttons and knife-handles, boxes, inlaying work, &c., are well known.

=PEARL′ASH.= This is prepared by calcining crude potashes on a reverberatory hearth, dissolving the calcined mass in water, and, after repose, decanting the clear solution, and evaporating it to dryness in flat iron pans, the product being constantly stirred towards the end to reduce it to a semi-granular state. Although purer, its richness in absolute alkali is less than that of the potashes from which it is prepared, being only from 47% to 51%. This exists almost entirely under the form of carbonate. The commercial value of this substance is determined by the ordinary processes of ALKALIMETRY.

=PEARL BARLEY.= See BARLEY.

=PEARL FLAVOUR.= See ESSENCE.

=PEARL WHITE.= This is a subchloride of bismuth; but the name is now commonly applied to trisnitrate of bismuth, which is sold for it.

=PEARLS (Rose).= _Syn._ ROSE BEADS. The petals of red roses beaten in an iron mortar for some hours, until they form a smooth, black paste, then rolled into beads and dried. Hard; very fragrant; take a fine polish.

=Pearls, to Polish.= Take very finely pulverised rotten stone, and make it into a thick paste by adding olive oil; then add sulphuric acid, a sufficient quantity to make into a thin paste.

This is to be applied on a velvet cork, rub quickly, and as soon as the pearl takes the polish wash it. This mixture when properly applied will give to pearl a brilliant polish.

=PEAS.= _Syn._ GARDEN PEAS, MOTOR P.; PISA, L. The seed of _Pisum sativum_ (Linn.). Poggiale found in 100 parts of common green peas, dried and shelled, 57 of starch, 21·7 of a nitrogenous substance (legumin), 1·9 of fatty matter, 3·2 of cellulose, 2·8 of ash, and 12·7 of water. In the fresh state (GREEN PEAS) they are nutritive, and, with the pods which contain them, are highly serviceable in scurvy. The last have been used for making beer. The dried seeds are still more nutritious, but are heavy and flatulent unless well cooked. For kitchen use ‘SPLIT PEAS’ should be chosen, and after having washed them in a little clean soft water, and allowed them to drain, they should be left to soak in cold soft water for at least 12 hours before applying heat to them, and should then be dressed in the same water in which they have been soaked, and be only gently simmered until they are reduced to a pulp. Additions of meat, vegetables, &c., should not be made until they have nearly arrived at this condition. ‘WHOLE PEAS’ require soaking for at least 18 or 20 hours.

A substitute for green peas in winter may be obtained by placing the dried seed on a flat dish, sprinkling them with water, and keeping them in a warm situation. In a few days germination commences, and, after it has proceeded sufficiently far, the whole is dressed in the usual manner. An easier and simpler plan is to preserve the green peas, when they are in season, by the common method adopted for gooseberries and other like fruit.

Pea flour is sometimes used to adulterate ordinary flour. It is never added to this latter to a greater extent than 4 per cent., as, if this quantity be exceeded, it makes the bread heavy and dark.

It is also used as a sophisticant for other substances, particularly for butter.

=Peas, Is′sue.= _Syn._ PISA PRO FONTICULIS, L. Orange berries, or the small unripe fruit of the orange tree, dried, and smoothed in a lathe. See ISSUE.

=PEB′BLE.= The trade name for the transparent colourless variety of rock crystal or quartz used for the lenses of spectacles instead of glass, over which, from its extreme hardness, it has the advantage of being little apt to be scratched.

=PEC′TIC ACID.= The name given by Braconnot to an acid which is found very generally diffused throughout the vegetable kingdom.

_Prep._ From carrot roots, from which the juice has been pressed out, by boiling them with 1/25th part of their weight of carbonate of potassium, and about 6 times their weight of water, until the liquid becomes gelatinous when neutralised with an acid. A pectate of potassium is formed, from which the acid may be obtained by neutralising the alkali with a stronger acid, or by carefully adding a solution of chloride of calcium as long as a gelatinous precipitate (pectate of calcium) falls, and, after washing this with water, decomposing it with dilute hydrochloric acid.

_Prop., &c._ A colourless jelly, having an acid reaction; scarcely soluble in cold water, more so in hot water; and precipitated by acids, alkalies, alcohol, salts, and even sugar. Its compounds with the bases are called pectates. By long boiling with solution of caustic alkali it is converted into metapectic acid, which does not gelatinise. (See _below_.)

=PEC′TIN.= _Syn._ VEGETABLE JELLY. Obtained by adding alcohol to the juice of ripe currants or other fruit, until a gelatinous precipitate forms, which must be drained, washed with a little weak alcohol, and dried.

_Prop., &c._ In the moist state it forms a neutral, tasteless, soluble, transparent jelly; when dried, a translucent mass, closely resembling isinglass; boiled with water, or with dilute acids, it is converted into parapectin and metapectin; in the presence of alkalies, these, as well as pectin, are changed into pectic acid, and by continuing the ebullition for some time longer, into metapectic acid, which is not gelatinous. See PECTIC ACID.

=PECTORAL BALSAM.= The same as BALSAM OF HONEY, which see. The reference to ‘Pectoral balsam,’ which occurs at the end of the article ‘Balsam of Honey,’ conveys the impression that it is a different medicine. This is an error.

=PEC′TORALS.= Under this head are popularly included all the various remedies employed in breath or chest diseases.

=PEDIC′ULI.= See LOUSE.

=PEL′LICLE.= See CRYSTALLISATION.

=PEL′LITORY.= _Syn._ PELLITORY OF SPAIN; (PELLITORY ROOT; PYRETHRI RADIX, B. P.); PYRETHRUM (Ph. L. & E.), L. The root of _Anacyclus Pyrethrum_. It is a powerful topical excitant. It is chiefly employed as a masticatory in headache, toothache, palsy of the tongue, and facial neuralgia and rheumatism; and made into a tincture with rectified spirit, it is a common remedy among dentists for the toothache. Internally, it has been given as a gastric stimulant, and in intermittents, &c. Half to 1 dr. may be chewed at a time.

=PEL′TRY.= The name applied to fur skins in the state in which they are received from the hunters. To prepare them as furs, the inside of them is generally first ‘tawed’ by the application of a solution of alum. They are next well dusted over and rubbed with hot plaster of Paris or whiting, and are, lastly, thoroughly dried and brushed clean. When it is desired to change or modify their colour, the grease being removed by lime water or a weak soda lye, they are stretched out on a table or board, and the ordinary liquid mordants and dyes are applied to them hot by means of a painter’s brush.

The furs of the rabbit and hare are rendered fit for the purposes of the felt and hat manufacturers by a process called by the French ‘_sécretage_,’ This consists in thoroughly moistening the hair with a solution of quicksilver, 1 part, in aquafortis, 16 parts, diluted with half to an equal bulk of water. This is applied with a brush, and the moistened skins being laid together, face to face, are dried as rapidly as possible in a stove room. See FURS.

=PEMPHIGUS.= A disease of the skin, in which large vesicles or blisters filled with a serous fluid, develop themselves. In the mild form of the disorder the blisters vary in size from a pea to a chestnut. They chiefly attack the extremities, and break after three or four days, when they then give rise to a thin scab, which soon heals and disappears without causing any bodily derangement.

In the acute form, however, there is a considerable constitutional disturbance, which shows itself in the shape of more or less fever and inflammation; the blisters too are larger, and the scabs very irritable and obstinate. Children during teething, or owing to injudicious diet, are frequently subject to this kind of pemphigus. There is also a chronic variety of the disease, which varies but slightly from the acute form, except that it continues longer. Old people are those who principally suffer from this chronic pemphigus.

A mild attack seldom calls for any treatment; the best course to pursue in the case of an acute one is to administer some saline aperient, to adopt a moderately low diet, and to protect the exposed parts caused by the breaking of the blister by applying to them some simple dressing, such as spermaceti ointment.

When the case becomes chronic it will be advisable to consult the medical practitioner.

=PENALTIES.= The following sections of the Public Health Act of 1875 refer to various offences for which penalties may be inflicted under the statute:——

BUILDING or re-erecting a house in an urban district without proper drains, &c., £50 (s. 25). For building or re-erecting a house in any district without proper sanitary conveniences (privies, &c.), £20, or less (s. 35).

Unauthorised building over sewers or under streets in an urban district, £5 penalty, and 40s. per day during continuance of offence (s. 26).

BURIAL. For obstructing a justice’s order with regard to the burial of a person who has died from an infectious disease, &c., £5, or less (s. 142).

BYE-LAWS. Penalties may be imposed by local authorities for the contravention of bye-laws; such penalties are not to exceed £5, and for continuing offences further penalties of sums not exceeding 40s. a day (s. 183). Penalty for injury or defacement of any board, &c., on which a notice or bye-law of any authority is inscribed by the authority of the Government Local Board, or of the local authority, £5, or less (s. 306).

CELLARS, Unauthorised occupation of, 20s. per day (s. 73).

CLEANSING AND WHITEWASHING, &c., Failure to comply with notice to cleanse and whitewash a house, 10s. per day (s. 46).

CONTRACTS. All contracts are to specify some pecuniary penalty (s. 174). Officers or servants being concerned or interested in contracts, accepting fees, are liable to a penalty of £50, recoverable with full costs of suit.

DISINFECTION. Failure to comply with notice to disinfect and cleanse articles and premises, not less than 1s. and not more than 10s. per day. Expenses of local authority doing the work may also be recovered (s. 120). Failure to disinfect public conveyances after conveying infected persons, £5, or less (s. 127). For letting infected houses without proper disinfection, £20, or less (s. 128).

DRAINS, &c. Unauthorised connection of a drain with a sewer, £20, or less (s. 21). For neglecting to comply with notice for the construction of privies, &c., for factories, £20, or less, and 40s. per day. For non-compliance with notice for the construction of drains, privies, &c., 10s. per day (s. 41).

EPIDEMIC DISEASES. For violation or obstruction of the regulations of the Local Government Board with regard to epidemic diseases, £5, or less (s. 140).

EXPOSURE of infected persons or things, £5, or less (s. 126).

HOUSES OR ROOMS. Making false statements with regard to infectious diseases for the purpose of letting, £20, or less, or imprisonment for one month with or without hard labour (s. 129).

LODGING-HOUSES. Receiving lodgers in unregistered houses, failure to make a report, failure to give notice of infectious diseases, £5, or less, and 40s. per day during continuance of offence. Refusal or neglect to affix or renew notice of regulation in common lodging-houses, £5, or less, and 10s. a day during continuance of offence after conviction (s. 79). For neglecting the limewashing and cleansing of lodging-houses according to the Act 40s., or less (s. 82).

MANURE. Failure to comply with a notice of urban authority to periodically remove manure, &c., 20s. a day (s. 50).

MEAT. For exposing for sale or having in possession unsound meat and other articles of food specified in the Act, £20, or less, for each carcase or piece of meat, or fish, &c., or three months imprisonment with or without the option of a fine (s. 117). For obstruction of officer inspecting the food, £5, or less (s. 118).

MORTGAGE OF RATE. Refusal of custodian of register to permit inspection, £50, or less. Neglect or refusal of clerk to register transfer of mortgage, £20, or less.

NUISANCE. The court may impose a penalty of £5, or less, with regard to nuisances generally (s. 98). For want of diligence in carrying out the order to abate nuisance, 10s. per day; for contravention of order, if wilful, 20s. per day during such contrary action, besides the expenses of the local authority in abating the nuisance (s. 98).

For nuisance of pigs, pigsties, and the contents of cesspools, &c., overflowing, 40s., or less, and 5s. per day during continuance of offences (s. 47).

OBSTRUCTION. For wilful obstruction of member of, or person authorised by local authority, £5, or less (s. 306).

Obstruction of owner by occupier in carrying out any of the provisions of the Act, £5 per day, commencing twenty-four hours after non-compliance with the justice’s order (s. 306).

OFFICES. Certain offices are not to be held by the same person. Penalty for offence, £100, recoverable with full costs of suit (s. 192).

ORDER OF JUSTICES. Refusal to obey order for admission of local authority, £5, or less (s. 103).

RATES. Refusal of officers in custody of rate-books, valuation lists for the relief of the poor, &c., to permit inspection, £5, or less (s. 212).

Refusal of person to permit inspection of rate, £5, or less (s. 219).

SCAVENGING. Obstruction of the contractor or local authority in scavenging the streets or in removal of refuse, £5, or less (s. 42). Neglect of local authority to scavenge after undertaking to do so, 5s. per day (s. 43).

STREETS. Wilful unauthorised displacement or injury of pavement stones, injury to fences, &c., of streets vested in urban authority, £5, or less, and a further penalty of 5s. or less for every square foot of pavement injured, &c. Compensation may also be awarded by the court for injury to trees (s. 149).

For building or bringing forward buildings beyond the general line of the houses in the street in an urban district, 40s. per day after written notice (s. 156).

TRADE, OFFENSIVE. Unauthorised establishment of in an urban district, £50, and 40s. per day during continuance of offence (s. 112). Nuisance arising from offensive trade is punishable by penalty——for first offence not less than 40s., and not exceeding £5; for second or any subsequent offence, double the amount of the last penalty which has been imposed, but in no case to exceed £200 (s. 114).

WATER. Pollution of by gas, £280; and when offence is continued at the end of twenty-four hours’ notice, £20 per day (s. 68).

For injuring water-meters, 40s., or less, and the damage sustained may also be recovered (s. 60).

WORKS. For wilful damage of works or property belonging to a local authority, in cases where no other penalty is provided, £5, or less (s. 307).

⁂ All penalties, forfeitures, costs, and expenses, directed to be recovered in a summary manner, or not otherwise provided for, may be prosecuted and recovered under the “Summary Jurisdiction Acts” before a court of summary jurisdiction (P. H. S. 251); but proceedings for the recovery of penalties are only to be taken by the person aggrieved, or by the local authority of the district, except the consent in writing of the Attorney-General be obtained. But this restriction does not apply to the proceedings of a local authority with regard to nuisances, offensive trades, houses, &c., without their district, in cases in which the local authority are authorised to take proceedings with respect to any act or default (s. 253).

Unless otherwise provided for the penalty is thus applied: One half goes to the informer, and the remainder to the local authority of the district in which the offence was committed; but if the local authority be the informer, they are entitled to the whole of the penalty recovered.

All penalties and sums recovered by a local authority are paid to the treasurer, and carried to the account of the fund applicable to the general purposes of the Public Health Act.

(The justices or court have power to reduce penalties imposed by 6 Geo. IV, c. 78. P. H. Part III.)

=PEN′CILS.= This name is applied to the small brushes made of camel’s hair used by artists, as well as to the plumbago crayons familiarly known as black-lead pencils. The last are prepared by one or other of the following methods:——

1. The blocks of plumbago are exposed to a bright-red heat in a closely covered crucible, and are afterwards sawn into minute sticks, and mounted in cases of cedar or satin wood.

2. The plumbago, in powder, is calcined as before, and then mixed with an equal, or any other desired proportion of pure washed clay, also in powder, after which the mixture is reduced to a plastic state with water, and pressed into grooves cut on the face of a smooth board, or into well-greased wooden moulds, in which state it is left to dry. When dry, the pieces are tempered to any degree of hardness by exposing them, surrounded by sand or powdered charcoal, in a closely covered crucible to various degrees of heat. The crucible is not opened until the whole has become cold, when the prepared ‘slips’ are removed and mounted as before. This method was invented by M. Conté in 1795.

3. The dough or paste, prepared as last, is reduced to the required form by forcing it through a perforated plate (in a similar manner to that adopted for coloured crayons), or into minute metallic cylinders, from which it may be readily shaken after it has become partially dry.

_Obs._ The _leads_ for some varieties of drawing-pencils are immersed for a minute in very hot melted wax or suet before mounting them. To the composition for others a little lampblack is added, to increase and vary the degree of blackness. The pencils for asses’ skin books and prepared paper are tipped with ‘fusible metal.’ Numerous improvements in pencil cases and pencil mounts have been patented of late years by Stevens and others.

=PENNYROY′AL.= _Syn._ PULEGIUM (Ph. L. & E.), MENTHA P. (Ph. D.), L. “The recent and dried flowering herb of _Mentha pulegium_, Linn.” (Ph. L.) PENNYROYAL TEA is a popular emmenagogue, expectorant, and diaphoretic, and is in common use in asthma, bronchitis, hooping-cough, hysteria, suppressions, &c. Water, essence, oil, and spirit of pennyroyal are officinal. They are now chiefly used as mere adjuncts or vehicles.

=PENTASTOMATA.= There are two varieties of this entozoon——the _Pentastoma denticulatum_, which Leuckart has shown to be the larvæ of the _Pentastoma tænoides_, and the _Pentastoma constrictum_. The _P. denticulatum_ infests the human liver and small intestines. The _P. constrictum_ does not appear to be known in this country. The latter appears to have caused death by setting up peritonitis. According to Dr Aitken these parasites are provided with two pairs of hooks or claws, placed on each side of a pit or mouth, on a flattened head. He says: “These claws appear to be implanted in socket-like hollows or depressions, surrounded by much loose integument. These socket-like hollows appear to be elevated on the summit of the mass of tissues which lies underneath the folds of integuments surrounding the base of the hooks. These parts are regarded as the feet of the parasite, and the hooks are the fore claws. The pit or mouth is of an oval shape, the long axis of the oval lying in the direction of the length of the worm.

“The less or outer margin of the pit is marked by a well-defined, thin line. There are no spines nor hooks on the integument of the elongated body.”

=PEPPER (Black).= _Syn._ PEPPER; PIPER, B. P.; NIGRI BACCÆ, PIPER NIGRUM (Ph. L., E., & D.), L. “The immature fruit (berry) of _Piper nigrum_, Linn., or the black pepper vine.” (Ph. L.)

_Pur._ The ground black pepper of the shops is universally adulterated; in fact, the public taste and judgment are so vitiated that the pure spice is unsaleable. A most respectable London firm, on commencing business, supplied their customers with unadulterated ground pepper, but in 3 cases out of every 4 it was returned on their hands and objected to, on account of its dark colour and rich pungency, which had induced the belief that it was sophisticated. The house alluded to was therefore compelled by the customers to supply them with an inferior, but milder and paler, article. The substances employed to lower black pepper are known in the trade as——‘P. D.,’ ‘H. P. D.,’ and ‘W. P. D,’——abbreviations of pepper dust, hot pepper dust, white pepper dust. The first is composed of the faded leaves of autumn, dried and powdered; the second, the ground husks (hulls) of black mustard, obtained from the mustard mills; and the third is common rice, finely powdered. Equal parts of black peppercorns, H. P. D., and W. P. D., form the very best ground pepper sold. The ordinary pepper of the shops does not contain more than 1/8th to 1/6th of genuine pepper, or 2 to 2-1/2 oz. in the lb. Very recently, ground oil-cake or linseed meal has been chiefly employed as the adulterant, instead of the old ‘P. D,’

Dr Parkes[92] says: “The microscopic characters of pepper are rather complicated. There is a husk composed of four or five layers of cells and a central part. The cortex has externally elongated cells, placed vertically, and provided with a central cavity, from which lines radiate towards the circumference; then come some strata of angular cells, which, towards the interior, are larger and filled with oil. The third layer is composed of woody fibre and spiral cells. The fourth layer is made up of large cells, which towards the interior become smaller and of a deep red colour; they contain most of the essential oil of the pepper. The central part of the berry is composed of large angular cells, about twice as long as broad. Steeped in water, some of these cells become yellow; others remain colourless. It has been supposed that these yellow cells contain piperine, as they give the same reaction as piperine does; namely, the tint is deepened by alcohol and nitric acid, and sulphuric acid applied to a dry section causes a reddish hue.” (Hassal.)

[Footnote 92: ‘Practical Hygiene.’]

_Uses, &c._ Black pepper is a powerful stimulant, carminative, and rubefacient. Its use in moderation, as a condiment, is peculiarly serviceable to persons who are of cold habit, or who suffer from weak digestion; but in inflammatory habits, and in affections of the mucous membranes, it is generally highly injurious. As a medicine it is often serviceable in nausea, vomiting, chronic diarrhœa, and agues. In North America a common remedy for the last is 1/2 oz. of ground pepper stirred up with a glassful of warm beer; or a like quantity made into a tincture by steeping it in 5 or 6 times its weight of gin, rum, or whisky, for a few days.

Prepared black pepper is made by steeping the berries for 3 days in 3 times their weight of vinegar, and then drying and grinding them. It is milder than common pepper. See CONFECTIONS, PIPERINE, &c.

=Pepper, Cayenne.= _Syn._ BIRD PEPPER, CHILI P., GUINEA P., INDIAN P., RED P.; PIPER CAPSICI, P. CAYENNE, L. This is prepared from chillies, or the pods of _Capsicum frutescens_, or from _Capsicum baccatum_, or bird pepper, but generally from the first, on account of its greater pungency and acrimony; and, occasionally, from _Capsicum annuum_ or medicinal capsicum.

_Prep._ 1. From the dried pods (powdered), 1 lb.; and wheaten bread or captain’s biscuits (heated until they are perfectly dry and brittle, and begin to acquire a yellow colour throughout, and then powdered), 7 lbs.; mixed and ground together. Colouring matter and common salt are frequently added, but are unnecessary.

2. As the last, but making the mixture into a dough with water, then forming it into small cakes, drying these as rapidly as possible at a gentle heat, and then grinding them.

3. (Loudon.) The ripe pods, dried in the sun, are stratified with wheaten flour in a dish or tray, and exposed in a stove-room or a half-cold oven until they are quite dry; they are then removed from the flour, and ground to fine powder; to every oz. of this powder 1 lb. (say 15 oz.) of wheaten flour (including that already used) are added, and the mixture is made into a dough with a little tepid water and a teaspoonful of yeast; after fermentation is well set up, the dough is cut into small pieces, and baked in a slow oven until it is perfectly hard and brittle; it is then beaten or ground to powder, and forms ‘cayenne pepper.’

Pure cayenne pepper, when burnt, leaves a scarcely perceptible quantity of white ash; a red-coloured ash indicates the presence of red ochre, brick-dust, Armenian bole, or other earthy colouring matter. If red lead is present, it will be left behind under the form of a dark-coloured powder, or a small metallic globule.

_Pur._ The ‘cayenne pepper’ of the shops is often a spurious article, made by grinding a mixture of any of the reddish woods or sawdust with enough red pods or chillies to render the mixture sufficiently acrid and pungent. Common salt, colcothar, red bole, brick-dust, vermilion, and even red lead, are also common additions.

_Uses, &c._ The capsicums resemble the peppers, except in their greater energy and their pungency being unmodified by the presence of essential oil. As a condiment, under the form of cayenne pepper, and in all diseases in which the employment of a powerful stimulant or rubefacient is indicated, their uses are well known. In medicine the fruit of _Capsicum annuum_ (Linn.——Ph. E. & D.; _C. fastigiatum_, Blume——B. P., Ph. L.), or annual capsicum is ordered (CAPSICUM——Ph. L., E., & D.). The London College directs the fruit to be that of ‘Guinea,’ less than one inch long, oblong, cylindrical, and straight. See ESSENCE OF CAYENNE.

=Pepper, Prepared Cayenne=, is the residuum of cayenne——vinegar, essence, or tincture, dried and ground (see _below_).

=Pepper (Soluble) Cayenne.= _Syn._ CRYSTALLISED SOLUBLE CAYENNE. _Prep._ 1. Capsicum pods (recent, ground in a pepper mill), 1 lb.; rectified spirit, 2-1/2 pints; proceed by percolation so as to obtain 2-1/2 pints; from this distil one half of the spirit by the heat of a water bath; to the residuum add of fine dry salt, 5 lbs.; mix them well together, and dry the mixture at a very gentle heat, frequently stirring; lastly rub it through a sieve, and put it into warm dry bottles. It is usually coloured with a little vermilion or rouge (sesquioxide of iron), but it possesses an agreeable colour without it,

2. Essence of cayenne (No. 1, page 652), 6 pints; distil off 3 pints, add to the residual liquor of dry salt 12 lbs.; mix well, dry by a gentle heat, and otherwise proceed as before.

3. Capsicums (ground), 3 lbs.; red sanders or Brazil wood (sliced or rasped), 10 oz.; rectified spirit, 1 gall.; macerate for 14 days, then express the tincture, filter, distil off one half, add of dry salt, 15 lbs., and proceed as before.

4. As the first formula, with the addition of a strong decoction of saffron, q. s. It gives a beautiful colour to soups, &c.

_Obs._ The above formulæ are those actually employed by the houses most celebrated for their ‘soluble cayenne.’ The products are of the very finest quality, and are perfectly wholesome. We speak from an extensive experience in the manufacture. The spirit distilled from the essence forms a most suitable menstruum for making fresh essence or tincture of cayenne.

=Pepper, Cu′beb.= See CUBEBS.

=Pepper, Jamai′ca.= See PIMENTO.

=Pepper, Kit′chen.= See SPICE.

=Pepper, Long.= _Syn._ PIPERIS LONGI FRUCTUS, PIPER LONGUM (Ph. L. & E.), L. “The immature fruit (dried female spikes) of _Piper longum_, Linn.” (Ph. L.), or long-pepper vine. The spikes are about 1-1/2 inch in length, with an indented surface, and are of a dark-grey colour. In its general properties it resembles black pepper, but it is less aromatic, though equally pungent. Elephant pepper is merely a larger variety of this species. (Gray.) The root and stems, sliced and dried, form the ‘pippula moola’ of the East Indies. (Roxburgh.)

=Pepper, Red.= See CAYENNE.

=Pepper, White.= _Syn._ PIPER ALBUM, L. This is made by either soaking ordinary black pepper in a solution of common salt, until the outside skins are soft, and then rubbing them off in the hands, or by merely rubbing off the skins of the over-ripe berries that fall from the vines. An inferior quality is made by bleaching black pepper with chlorine.

_Obs._ The use of white pepper instead of black is an instance of the sacrifices made to please the eye. Pure white pepper has only about 1-4th of the strength of pure black pepper, whilst it is nearly destitute of the fine aroma of the latter. It also contains a mere trace of piperina or piperine, one of the most valuable constituents of black pepper.

=PEP′PER PODS.= Capsicums. See CAYENNE PEPPER.

=PEP′PERMINT.= _Syn._ MENTHA PIPERITA (Ph. L., E., & D.), L. “The recent and dried flowering herb of _Mentha piperita_” (Ph. L.), or garden peppermint. The flavour and odour of this herb are well known. It is the most pleasant and powerful of all the mints. Peppermint water and the essential oil have long been employed in nausea, griping, flatulent colic, hysteric, diarrhœa, &c.; but in regular practice chiefly to cover the taste of nauseous medicines, or as an adjunct or vehicle for more active remedies. See OILS (Volatile), WATERS, &c.

=PEP′SIN.= _Syn._ GASTERACE, CHYMOSIN. A peculiar principle found in the gastric juice, and which, in conjunction with hydrochloric acid, also present in the stomach, confers upon it the power of digesting certain portions of the food, and of dissolving, as Tuson has shown, calomel and other mineral substances.

_Prep._ 1. (Beale, ‘Med. Times & Gaz.,’ February 10th, 1872, p. 152.) “The mucous membrane of a perfectly fresh pig’s stomach is carefully dissected from the muscular coat, and placed on a flat board. It is then lightly cleansed with a sponge and a little water, and much of the mucus, remains of food, &c. carefully removed. With the back of a knife, or with an ivory paper-knife, the surface is scraped very hard, in order that the glands may be squeezed and their contents pressed out. The viscid mucus thus obtained contains the pure gastric juice with much epithelium from the glands and surface of the mucous membrane. It is to be spread out upon a piece of glass, so as to form a very thin layer, which is to be dried at a temperature of 100° over hot water, or _in vacuo_ over sulphuric acid. Care must be taken that the temperature does not rise much above 100 F°., because the action of the solvent would be completely destroyed. When dry the mucus is scraped from the glass, powdered in a mortar, and transferred to a well-stoppered bottle. With this powder a good digestive fluid may be made as follows:

Of the powder 5 grains. Strong hydrochloric acid 18 drops. Water 6 ounces.

Macerate it at a temperature of 100° for an hour. The mixture may be filtered easily, and forms a perfectly clear solution very convenient for experiment.

“If the powder is to be taken as a medicine, from two to five grains may be given for a dose, a little diluted hydrochloric acid in water being taken at the same time. The pepsin powder may be mixed with the salt at a meal. It is devoid of smell, and has only a slightly salt taste. It undergoes no change if kept perfectly dry, and contains the active principle of the gastric juice almost unaltered.

“The method of preparing this pepsin was communicated to Mr Bullock, of the firm of Messrs Bullock and Company, 3, Hanover Street, Hanover Square, who at once adopted it for the preparation of medicinal pepsin, and soon improved upon it in some particulars. The dose is from 2 to 4 or 5 grains.——_Test._ 4/5ths of a grain of this pepsin, with 10 drops dilute hydrochloric acid and an ounce of distilled water, dissolve 100 grains of hard-boiled white of egg in from twelve to twenty-four hours. In the body probably twice this quantity of white of egg or even more would be dissolved in a comparatively short space of time. The digestive powder prepared from the pig’s stomach retains its activity for any length of time if kept dry. I had some which had been kept in a bottle for upwards of five years, and still retained its active power unimpaired. The solution made with this pepsin and hydrochloric acid was nearly tasteless and inodorous. One pig’s stomach, which costs sixpence, will yield about 45 grains of the powder prepared as above described.

“Gradually the usefulness of this preparation of pepsin of the pig was found out, and it had to be prepared in increasing quantities. I should be afraid to say how many pigs’ stomachs have been used of late years during the winter season.

“In 1857 Dr. Pavy carefully examined the pepsin prepared and sold by many different firms, and found that this dried mucus of the pig’s stomach was the most active of them all (‘Medical Times and Gazette,’ 1857, vol. i, p. 336). In 1870 Professor Tuson instituted a still more careful comparative examination, and with a similar result (‘Lancet,’ August 13th, 1870); for he found that this preparation was _twenty-five times stronger than some others that he obtained for examination_.”

2. (Scheffer, ‘Pharm. Journ.,’ March 23rd, 1872, p. 761.) “Of the well-cleaned fresh hog stomach the mucous membrane is dissected off, chopped finely and macerated in water acidulated with muriatic acid for several days, during which time the mass is frequently well stirred. The resulting liquid, after being strained, is, if not clear, set aside for at least twenty-four hours in order to allow the mucus to settle. To the clarified liquid the same bulk of a saturated solution of sodium chloride is added, and the whole thoroughly mixed. After several hours the pepsin, which, by the addition of chloride of sodium, has separated from its solution, is found floating on the surface, from whence it is removed with a spoon and put upon cotton cloth to drain; finally it is submitted to strong pressure, to free it as much as possible from the salt solution.

“The pepsin, when taken from the press and allowed to become air-dry, is a very tough substance, and presents, according to thickness, a different appearance, resembling in thin sheets parchment paper, and in thick layers sole leather; its colour varies from a dim straw yellow to a brownish yellow. Besides a little mucus, it contains small quantities of phosphate of lime and chloride of sodium, which, however, do not interfere with its digestive properties, as they are found also in normal gastric juice.

“In order to get a purer article I redissolve the pepsin, as obtained after expression, in acidulated water, filter the solution through paper and precipitate again with a solution of sodium chloride; the precipitate, after draining and pressing, is now free of phosphate of lime and mucus, but still contains salt. In the freshly precipitated state the pepsin is very readily soluble in water, and cannot therefore be freed from adhering salt by washing.

“By allowing the pressed sheet of pepsin to get perfectly air-dry——whereby it becomes coated with a white film and small crystals of chloride of sodium——and by immersing it then in pure water for a short time, the greater part of sodium chloride can be extracted, but it has to be done very rapidly, as the pepsin swells up considerably and loses its tenacity. By operating in this matter I have obtained a pepsin which dissolves in acidulated water to quite a clear colourless liquid, but as it still contains traces of salt, I prefer to call it purified pepsin.”

3. (B. Ph.) A preparation of the mucous lining of a fresh and healthy stomach of the pig, sheep, or calf. The stomach of one of these animals, recently killed, having been cut open and laid on a board with the inner surface upwards, any adhering portions of food, dirt, and other impurity, are to be removed and the exposed surface slightly washed with cold water; the cleansed mucous membrane is then to be scraped with a blunt knife or other suitable instrument, and the viscid parts thus obtained is to be immediately spread over the surface of glass or glazed earthenware, and quickly dried at a temperature not exceeding 100° F. the dried residue is to be reduced to powder, and preserved in a stoppered bottle.——_Dose_, 2 to 5 grains.

=Pepsin, Saccharated.= To work it into saccharated pepsin (‘American Journal of Pharmacy,’ January, 1871) the damp pepsin, as it is taken from the press, is triturated with a weighed quantity of sugar of milk to a fine powder, which, when it has become air-dry, is weighed again, the quantity of milk sugar subtracted, and so the amount of pepsin found. The strength of this dry pepsin is now ascertained by finding how much coagulated albumen it will dissolve at a temperature of 100° F. in five or six hours, and after this sufficient milk sugar is added to result in a preparation of which ten grains will dissolve one hundred and twenty grains of coagulated albumen, and this preparation I have called saccharated pepsin.

=Pepsin with Starch.= Pepsin mixed with starch is the _medicinal Pepsine_ of M. Boudault; the _Poudre nutrimentive_ of M. Corvisart.

=PERCENTAGE.= Literally, “by the hundred.” In commerce the term is applied to an allowance duty or commission on a hundred. (WEBSTER.)

=PERCHLO′′RATE=, _Syn._ PERCHLORAS, L. A salt of perchloric acid.

The perchlorates are distinguished from the chlorates by their great stability, and by not turning yellow when treated with hydrochloric acid. Like the chlorates, they give off oxygen when heated to redness. They may be prepared by directly neutralising a solution of the acid with a solution of the base. See POTASSIUM (Perchlorate of), and CHLORINE.

=PERCHLO′′RIC ACID.= See CHLORINE.

=PERCOLA′TION= _Syn._ METHOD OF DISPLACEMENT. A method of extracting the soluble portion of any substance in a divided state, by causing the menstruum to filter or strain through it. The ‘sparging’ of the Scotch brewers is an example of the application of this principle on the large scale. In _pharmacy_, the ‘method of displacement’ is frequently adopted for the preparation of tinctures, infusions, &c., and is, in some respects, superior to digestion or maceration. “The solid materials, usually in coarse or moderately fine powder, are moistened with a sufficiency of the solvent to form a thick pulp. In twelve hours, or frequently without delay, the mass is put into a cylinder of glass, porcelain, or tinned iron, open at both ends, but obstructed at the lower end by a piece of calico or linen, tied lightly over it as a filter; and the pulp being backed by pressure, ranging as to degree with different articles, the remainder of the solvent is poured into the upper portion of the cylinder, and allowed gradually to percolate. In order to obtain the portion of the fluid which is absorbed by the residuum, an additional quantity of the solvent is poured into the cylinder, until the tincture which has passed through equals in amount the spirit originally prescribed. The spirit employed for this purpose is then recovered, for the most part, by pouring over the residuum as much water as there is spirit retained in it, which may be easily known by an obvious calculation in each case. The method of percolation is now preferred by all who have made sufficient trial of it to apply it correctly.” (Ph. E.)

The first portion of liquid obtained by the method of displacement is always in a state of high concentration. In general it is a simple solution of the soluble ingredients of the crude drug in the fluid employed. But sometimes the solvent, if compound, is resolved into its component parts, and the fluid which passes through at any given time is only one of these, holding the soluble parts of the drug in solution. Thus if diluted alcohol be poured over powder of myrrh, in the cylinder of the percolator, the fluid which first drops into the receiver is a solution of an oily consistence, chiefly composed of resin and volatile oil, dissolved in alcohol. In like manner, when the powder of gall-nuts is treated in the same way by hydrated sulphuric ether, two layers of fluid are obtained, one of which is a highly concentrated solution of tannin in the water of the ether, and the other a weak solution of the same principle in pure ether. In all cases, therefore, in which it is not otherwise directed it is absolutely necessary to agitate the several portions of the liquid obtained by percolation together, in order to ensure a product of uniform strength or activity.

Several forms of displacement apparatus are employed by different operators. A simple and useful one is that figured in the margin. It has also the advantage of being inexpensive, and may be made by any worker in tin plate.

In operating on some substances it is found advantageous to hasten the process by pressure. This may be effected by any of the methods adopted for that purpose, and already described under FILTRATION. An ingenious little apparatus, which is well adapted for small quantities, is shown in the _engr._ By pouring mercury or water through (_e_), into the bottle (_c_), the air in the latter suffers compression, and acts in a corresponding manner on the percolating liquor in (_a_). The whole of the joints must be made air-tight.

The method of displacement, although apparently simple, requires for its successful application no inconsiderable amount of experience and skill in manipulation. The principal points to be attended to are——the reduction of the substance to the proper state of comminution (neither too coarse nor too fine),——the due regulation of the period of maceration according to the hardness, density, and texture of the substance; and, more important still,——the proper packing of the ingredients in the cylinder. On the correct performance of the last the success of the process mainly depends. Some substances require considerable pressure to be used, whilst others, when even lightly packed, scarcely permit the fluid to pass through them. When the material is too loosely packed, the menstruum passes through quickly, but without exerting its proper solvent action; when too great pressure is employed, percolation either progresses very slowly or not at all. On the whole, the firmness of the packing should be inversely as the solvent and softening power of the menstruum upon the solids exposed to its action; but to this rule there are many exceptions, and each substance may be said to require special treatment. An excellent plan, applicable to all substances, and especially to those of a glutinous or mucilaginous nature, is to mix the powder with an equal bulk of well-washed siliceous sand before rubbing it up with the menstruum. In reference to the coarseness of the powder it must be observed that substances which readily become soft and pappy when wetted by the menstruum, should not be used so fine as those that are more woody and fibrous, and not of a glutinous or resinous nature.

The ‘method of displacement’ has the advantage of expedition, economy, and yielding products possessing considerable uniformity of strength; but the difficulties attending its application by the inexperienced are serious obstacles to its general adoption in the laboratory. It answers admirably for the preparation of all tinctures that are not of a resinous nature, and for most infusions of a woody and fibrous substances, as roots, woods, barks, leaves, seeds, insects, &c., and particularly when cold or tepid water is taken as the solvent. It is also especially adapted for the preparation of concentrated infusions and essences, as they may thus be obtained of any required strength without loss, or requiring concentration by heat, which is so destructive to their virtues.

“When (ordinary) tinctures are made in large quantities, displacement is never likely to supersede maceration, on account of any practical advantages it may possess. If the prescribed directions be duly attended to, the process of maceration is unexceptionable. The process is more simple than the other; the mode of operating is more uniform, it is, in fact, always the same; it requires less of skill and dexterity in conducting it; it requires less constant attention during its progress which, in operating on large quantities is a consideration; and, finally, the apparatus required is less complicated. When, however, only small quantities of tincture are made at a time, and kept in stock, the adoption of the process of displacement will often be found convenient and advantageous. It offers the means of making a tincture in two or three hours, which, by the other process, would require as many weeks.” (Mohr and Redwood.)

Another useful application of the method of displacement is to the manufacture of extracts on the large scale. Here it is superior to any other plan. By the simple and inexpensive forms of apparatus in block-tin, stoneware, or glass, which have recently been designed for the purpose, not merely a first-class product is ensured, but a great saving in fuel and labour is at the same time effected. The reader is referred to the last edition of the ‘United States Pharmacopœia,’ and to papers by Messrs Saunders and Schweitzer in the ‘Pharmaceutical Year Book for 1873,’ and by Mr Campbell in the same publication for 1874, for additional information in the subject of “Percolation.” See BREWING, EXTRACT, TINCTURE, &c.

=PERCUS′SION.= _Syn._ PERCUSSIO, L. In _medicine_, the act of striking any part of the body with the fingers, or any instrument, to ascertain its condition.

=PERCUS′SION CAPS.= The composition employed to prime these articles is noticed under FULMINATING MERCURY.

=PER′FECT LOVE.= See LIQUEUR (Parfait amour).

=PER′FUME.= A substance that emits or casts off volatile particles which, when diffused through the atmosphere, agreeably affect the organs of smelling. The term is also applied to the volatile effluvia so perceived. The principal source of perfumes is the Vegetable Kingdom. Its flowers, seeds, woods, and barks furnish a rich variety, from which the most fastidious connoisseur may select his favourite bouquet. A few perfumes, as musk, ambergris, and civet, are derived from the Animal Kingdom; but none of these evolve an aroma comparable in freshness to that of the rose, or in delicacy to that of the orange-blossom, or even the unpretending jasmine. The Inorganic Kingdom yields not a single perfume, so called; nor has the science of chemistry yet been able to produce a single odoriferous compound from matter absolutely inorganic.

=PERFU′′MERY.= Perfumes in general; also the art of perfuming them. In its commercial application, this word embraces not merely perfumes, but also cosmetics, and other articles of a closely allied character employed at the toilet, the manufacture and sale of which constitute the trade of the modern perfumer. Formulæ for the preparation of all the more valuable perfumes, as well as of others met with in trade, both simple and compound, will be found under the heads COSMETICS, DEPILATORY, ESSENCE, HAIR DYES, OILS, PASTES, PASTILS, POMADE, SPIRIT, WATERS, &c., to which we refer the reader.

=PERFUMES, ACE′TIC.= See VINEGAR.

=Perfumes, Ammo′′niated.= These may be prepared by simply adding a sufficient quantity of ammonia to the liquid perfumes. When the articles are to be distilled, a cheaper plan is to add about 5 dr. of sal ammoniac and 8 dr. of carbonate of potassa to each pint of the article just before distillation. Ammoniated Cologne water is now a fashionable substance for spirit of sal volatile.

=PERIODIC ACID.= _Syn._ HYDRIC PERIODATE. (HIO_{4}.) 1. By passing a current of chlorine gas through a solution of sodic iodate, containing caustic soda, in the proportion of 3 atoms of the latter to one atom of sodic iodate. The hydrated basic sodic periodate, which crystallises out, is dissolved in diluted nitric acid, and precipitated by the addition of argentic nitrate; a normal argentic periodate crystallises as the liquid cools, and this salt being treated with water, is decomposed into a basic argentic periodate, which is insoluble, and periodic acid, which is dissolved. By evaporating the solution, the periodic acid may be obtained in deliquescent, oblique, rhombic prisms, which are somewhat soluble in alcohol and in ether.

2. From perchloric acid by the action of iodine. See IODINE.

=PERISTAL′TIC PERSUA′DERS.= See PILLS (Kitchener’s).

=PER′MANENT WHITE.= See BARIUM (Sulphate) and WHITE PIGMENTS.

=PERNAMBU′CO WOOD.= _Syn._ PEACH WOOD. The wood of _Cæsalpinia echinata_. It constitutes the paler variety of Brazil wood used by the dyers.

=PER′RY.= _Syn._ PYRACEUM, L. A fermented liquor prepared from pears in the same way as cider is from apples. The red rough-tasted sorts are principally used for this purpose. The best perry contains about 9% of absolute alcohol; ordinary perry from 5 to 7%.

Perry is a very pleasant-tasted and wholesome liquor. When bottled ‘champagne fashion,’ we have seen it frequently passed off for champagne without the fraud being suspected.

=PER′SIAN BER′RIES.= See FRENCH BERRIES.

=PERSPIRA′TION.= The liquid or vapour secreted by the ramifications of the cuticular arteries over the surface of the body. The perspiratory apparatus consists of a gland deeply seated in the corium, communicating by means of tubules (pores) with the surface of the scarf-skin.

The uses of the perspiratory functions appear to be to preserve the suppleness and sensibility of the skin, to maintain the temperature of the body at a uniform standard, and to remove from the system a number of compounds noxious to animal life. The perspiration “is a fluid whose regularity and continuance of exhalation are not merely conducive, but absolutely necessary, to health; without such regularity the animal temperature would run riot, and substances of an injurious quality would be allowed to permeate the finest and most delicate of the tissues of the body.” (Eras. Wilson.) “From the constriction or constipation of the cutaneous pores by the ambient air, especially when the body, beforehand put into a heat, is suddenly exposed thereunto, the serous particles which used to fly off continually in vapour, being now pent in, excite an intense and feverish effervescence; till, finding some other passage, either by the kidneys or by the glandules of the nose and windpipe, they are discharged by way of a catarrh; or, missing this separation, still keep up the ebullition, very often to the hazard of life, by suffocating the vital flame. And this is the natural consequence of obstructed insensible perspiration, which, in the vulgar phrase, is the same with what they mean by catching cold, and of which, give me leave to remark, that as fevers make two thirds of diseases infesting mankind, according to the computation of the judicious Sydenham, so two thirds of fevers very probably may take their rise from perspiration hindered.” (Daniel Turner.) Suppressed perspiration is also one of the commonest causes of diarrhœa.

=PERU′VIAN BALSAM.= See BALSAM OF PERU.

=PERU′VIAN BARK.= See CINCHONA.

=PES′SARY.= _Syn._ PESSUM, PESSARIUM, L. An instrument made of caoutchouc, gutta percha, box-wood, or ivory, inserted into the vagina to support the mouth and neck of the uterus. They are variously formed, to meet the prejudices of the party or the necessities of the case. The cup, conical, globe, and ring pessaries (pessi) are those best known.

Medicated pessaries are prepared by adding the active ingredients to a hard cerate, and pressing the mixture into the desired form. Astringents (various), belladonna, acetate of lead, mercury, &c., have been thus applied by Dr Simpson and others.

The different formulæ are given below:——

=Pessary, Alum.= _Syn._ PESSUS ALUMINIS. Alum, catechu, wax, of each 1 dr.; lard, 5-1/2 dr.

=Pessary, Belladonna.= _Syn._ PESSUS BELLADONNÆ. Extract of belladonna, 10 gr.; wax, 22-1/2 gr.; lard, 1-1/2 dr.; in each pessary.

=Pessary, Mercurial.= _Syn._ PESSUS HYDRARGYRI. Strong mercurial ointment, 1/2 dr.; wax, 1/2 dr.; lard, 1 dr. Mix.

=Pessary, Lead.= _Syn._ PESSUS PLUMBI. Acetate of lead, 7-1/2 gr.; white wax, 22-1/2 gr.; lard, 1-1/2 dr.

=Pessary, Iodide of Lead.= _Syn._ PESSUS PLUMBI IODIDI. Iodide of lead, 5 gr.; wax, 25 gr.; lard, 1-1/2 dr.

=Pessary, Tannin.= _Syn._ PESSUS TANNINI. Tannin, 10 gr.; wax, 25 gr.; lard, 1-1/2 dr.

=Pessary, Zinc.= _Syn._ PESSUS ZINCI. Oxide of zinc, 15 gr.; white wax, 22-1/2 gr.; lard, 1-1/2 dr.

=PEST′ILENCE.= See PLAGUE.

=PESTILEN′TIAL DISEASES.= All those diseases which are epidemic and malignant and assume the character of a plague. See CHOLERA, &c.

=PETONG′.= Same as _packfong_.

=PET′ROLENE.= The pure liquid portion of mineral tar. It has a pale yellow colour, a penetrating odour, and a high boiling point; is lighter than water, and is isomeric with the oils of turpentine and lemons. In its general proportions it resembles rectified mineral naphtha.

=PETRO′LEUM.= _Syn._ ROCK OIL, LIQUID BITUMEN, OIL OF PETRE; OLEUM PETRÆ, BITUMEN LIQUIDUM, L. PETROLEUM is an oil found oozing from the ground or obtained on sinking wells in the soil. To a limited extent it is met with in most countries of Europe and in the West India islands, but occurs in abundance in Pennsylvania and other parts of the United States and in Canada. It varies in colour from slight yellow to brownish black, in consistence from a thin mobile liquid to a fluid as thick as treacle, in specific gravity from 800 to 1100 (water being 1000) and is either clear and transparent or turbid and opaque. Petroleum is essentially a volatile oil, and when submitted to distillation yields gases homologous with light carburetted hydrogen of marsh-gas (Ronalds obtained three), liquids of similar constitution (Pelouze and Cahours isolated twelve), and solid paraffin-like bodies. Commercially petroleum is distilled so as to yield petroleum-spirit or mineral naphtha used as a substitute for turpentine and for burning in sponge-lamps and costermongers’ barrow-lamps; petroleum oil used all over the world as mineral lamp oil for illuminating purposes; and a heavy oil employed for lubricating machinery. The value of a sample of rock-oil is determined by thus distilling a weighed quantity in a small glass retort and weighing the products. The petroleum or middle product must be of such a character as to have a specific gravity not higher than 810 or 820 and to contain so little petroleum spirit that it only evolves inflammable vapour when heated to 100° Fahr. in the manner prescribed in the Petroleum Act, 1871 (see _below_). Any petroleum product or mineral oil which will not stand this test, and which is kept in larger bottles than one pint, and in larger total quantity than three gallons, cannot be stored or sold except by licence of the local authorities.

_Directions for Testing Petroleum to ascertain the temperature at which it gives off inflammable vapour._

The vessel which is to hold the oil shall be of thin sheet iron; it shall be two inches deep and two inches wide at the opening, tapering slightly towards the bottom; it shall have a flat rim, with a raised edge one quarter of an inch round the top; it shall be supported by this rim in a tin vessel four inches and a half deep and four and a half inches in diameter; it shall also have a thin wire stretched across the opening, which wire shall be so fixed to the edge of the vessel that it shall be a quarter of an inch above the surface of the flat rim. The thermometer to be used shall have a round bulb about half an inch in diameter, and is to be graduated upon the scale of Fahrenheit, every ten degrees occupying not less than half an inch upon the scale.

The inner vessel shall be filled with the petroleum to be tested, but care must be taken that the liquid does not cover the flat rim. The outer vessel shall be filled with cold, or nearly cold water; a small flame shall be applied to the bottom of the outer vessel, and the thermometer shall be inserted into the oil so that the bulb shall be immersed about one and a half inches beneath the surface. A screen of pasteboard or wood shall be placed round the apparatus, and shall be of such dimensions as to surround it about two thirds and to reach several inches above the level of the vessels.

When heat has been applied to the water until the thermometer has risen to about 90° Fahr., a very small flame shall be quickly passed across the surface of the oil on a level with the wire. If no pale blue flicker or flash is produced, the application of the flame is to be repeated for every rise of two or three degrees in the thermometer. When the flashing-point has been noted, the test shall be repeated with a fresh sample of the oil, using cold, or nearly cold water as before; withdrawing the source of heat from the outer vessel when the temperature approaches that noted in the first experiment, and applying the flame test at every rise of two degrees in the thermometer. See NAPHTHA, OILS (Mineral), &c.

=PEW′TER.= This is an alloy of tin and lead, or of tin with antimony and copper. The first only is properly called pewter. Three varieties are known in trade:——

_Prep._ 1. (PLATE PEWTER.) From tin, 79%; antimony, 7%; bismuth and copper, of each 2%; fused together. Used to make plates, teapots, &c. Takes a fine polish.

2. (TRIPLE PEWTER.) From tin, 79%; antimon, 15%; lead, 6%; as the last. Used for minor articles, syringes, toys, &c.

3. (LEY PEWTER.) From tin, 80%; lead, 20%. Used for measures, inkstands, &c.

_Obs._ According to the report of the French commission, pewter containing more than 18 parts of lead to 82 parts of tin is unsafe for measures for wine, and similar liquors and, indeed, for any other utensils exposed to contact with our food or beverages. The legal sp. gr. of pewter in France is 7·764; if it be greater, it contains an excess of lead, and is liable to prove poisonous. The proportions of these metals may be approximately determined from the sp. gr.; but correctly only by an assay for the purpose. See BRASS, GERMAN SILVER, LEAD, and TIN.

=PHARAOH’S SERPENTS.= 1. The chemical toy sold under this name consists of the powder of sulphocyanide of mercury made up in a capsule of tin foil in a conical mass of about an inch in height.

Ignited at the apex an ash is protruded, long and serpentine in shape. The fumes evolved are very poisonous.

2. (NON-POISONOUS.) Bichromate of potassium, 2 parts; nitrate of potassa, 1 part; and white sugar, 3 parts. Pulverise each of the ingredients separately, and then mix them thoroughly. Make small paper cones of the desired size, and press the mixture into them. They will then be ready for use, but must be kept from light and moisture.

=PHARMACY ACT.= The following are the principal clauses of the Pharmacy Act of 1860 (31 and 32 Victoria, cap. cxxi). We have separated and placed last, those provisions of the Act which relate to the sale of poisons:——

Whereas it is expedient for the safety of the public that persons keeping open shop for the retailing, dispensing, or compounding of poisons, and persons known as chemists and druggists should possess a competent practical knowledge of their business, and to that end, that from and after the day herein named all persons not already engaged in such business should, before commencing such business, be duly examined as to their practical knowledge, and that a register should be kept as herein provided, and also that the Act passed in the 15th and 16th years of the reign of her present Majesty, intituled ‘An Act for Regulating the Qualification of Pharmaceutical Chemists,’ hereinafter described as the Pharmacy Act, should be amended: Be it enacted, by the Queen’s most excellent Majesty, by and with the advice and consent of the Lords Spiritual and Temporal and Commons in this present Parliament assembled, and by authority of the same, as follows:——

From and after the 31st day of December, 1868, it shall be unlawful for any person to sell or keep open shop for retailing, dispensing, or compounding poisons, or to assume or use the title ‘Chemist and Druggist,’ or chemist or druggist, or pharmacist, or dispensing chemist, or druggist, in any part of Great Britain, unless such person shall be a pharmaceutical chemist, or a chemist and druggist, within the meaning of this Act, and be registered under this Act, and conform to such regulations as to the keeping, dispensing, and selling of such poisons as may from time to time be prescribed by the Pharmaceutical Society with the consent of the Privy Council (Clause 1).

Chemists and druggists within the meaning of this Act shall consist of all persons who at any time before the passing of this Act have carried on in Great Britain the business of a chemist and druggist in the keeping of open shop for the compounding of the prescriptions of duly qualified medical practitioners, also of all assistants and associates, who before the passing of the Act shall have been duly registered under or according to the provisions of the Pharmacy Act, and also of all such persons as may be duly registered under this Act (Clause 3).

All such persons as shall from time to time have been appointed to conduct examinations under the Pharmacy Act shall be, and are hereby declared to be, examiners for the purposes of this Act, and are hereby empowered and required to examine all such persons as shall tender themselves for examination under the provisions of this Act,[93] and every person who shall have been examined by such examiners, and shall have obtained from them a certificate of competent skill, and knowledge, and qualification, shall be entitled to be registered as a chemist and druggist under this Act, and the examination aforesaid shall be such as is provided under the Pharmacy Act for the purposes of a qualification to be registered as assistant under that Act, or as the same may be varied from time to time by any bye-law to be made in accordance with the Pharmacy Act as amended by this Act, provided that no person shall conduct any examination for the purposes of this Act until his appointment has been approved by the Privy Council (Clause 6).

[Footnote 93: See above.]

No name shall be entered in the register, except of persons authorised by this Act to be registered, nor unless the registrar be satisfied by the proper evidence that the person claiming is entitled to be registered; and any appeal from the decision of the registrar may be decided by the council of the Pharmaceutical Society; and any entry which shall be proved to the satisfaction of such council to have been fraudulently or incorrectly made may be erased from or amended in the register, by order in writing of such council (Clause 12).

“The registrar shall, in the month of January in every year, cause to be printed, published, and sold, a correct register of the names of all pharmaceutical chemists, and a correct register of all persons registered as chemists and druggists, and in such registers, respectively the names shall be in alphabetical order, according to the surnames, with the respective residences, in the form set forth in schedule (B) to this Act, or to the like effect, of all persons appearing on the register of pharmaceutical chemists, and on the register of chemists and druggists, on the 31st day of December last preceding, and such printed registers shall be called ‘The Registers of Pharmaceutical Chemists and Chemists and Druggists,’ and a printed copy of such registers for the time being, purporting to be so printed and published as aforesaid, or any certificate under the hand of the said registrar, and countersigned by the president or two members of the council of the Pharmaceutical Society, shall be evidence in all courts and before all justices of the peace and others, that the persons therein specified are registered according to the provisions of the Pharmacy Act or of this Act, as the case may be, and the absence of the name of any person from such printed register shall be evidence, until the contrary shall be made to appear, that such person is not registered according to the provisions of the Pharmacy Act or of this Act (Clause 13).

From and after the 31st day of December, 1868, any person who shall sell or keep an open shop for the retailing, dispensing, or compounding poisons, or who shall take, use, or exhibit the name or title of chemist and druggist, or chemist or druggist, not being a duly registered pharmaceutical chemist, or chemist and druggist, or who shall take, use, or exhibit the name or title pharmaceutical chemist, pharmaceutist, or pharmacist, not being a pharmaceutical chemist, or shall fail to conform with any regulation as to the keeping or selling of poisons, made in pursuance of this Act, or who shall compound any medicines of the British Pharmacopœia, except according to the formularies of the said Pharmacopœia, shall for every such offence be liable to pay a penalty or sum of £5, and the same may be sued for, recovered, and dealt with in the manner provided by the Pharmacy Act for the recovery of penalties under that Act; but nothing in this Act contained shall prevent any person from being liable to any other penalty, damages, or punishment to which he would have been subject if this Act had not been passed (Clause 15).

_Clauses of the Pharmacy Act relating to the sale of Poisons._

It shall be unlawful to sell any poison either by wholesale or retail, unless the box, bottle, vessel, wrapper, or cover in which such poison is contained be distinctly labelled with the name of the article and the word poison, and with the name and address of the seller of the poison; and it shall be unlawful to sell any poison of those which are in the first part of schedule (A) to this Act, or may hereafter be added thereto under section II of this Act, to any person unknown to the seller, unless introduced by some person known to the seller; and on every sale of any such article the seller shall, before delivery, make or cause to be made an entry in a book to be kept for that purpose, stating, in the form set forth in schedule (F) to this Act, the date of the sale, the name and address of the purchaser, the name and quantity of the article sold, and the purpose for which it is stated by the purchaser to be required, to which entry the signature of the purchaser and of the person, if any, who introduced him, shall be affixed; and any person selling poison otherwise than is herein provided, shall, upon a summary conviction before two justices of the peace in England or the sheriff in Scotland, be liable to a penalty not exceeding £5 for the first offence, and to a penalty not exceeding £10 for the second or any subsequent offence; and for the purposes of this section the person on whose behalf any sale is made by any apprentice or servant shall be deemed to be the seller, but the provisions of this section, which are solely applicable to poisons in the first part of the schedule (A) to this Act, or which require that the label shall contain the name and address of the seller, shall not apply to articles to be exported from Great Britain by wholesale dealers, nor to sales by wholesale to retail dealers in the ordinary course of wholesale dealing, nor shall any of the provisions of this section apply to any medicine supplied by a legally qualified apothecary to his patient, nor apply to any article when forming part of the ingredients of any medicine dispensed by a person registered under this Act provided such medicine be labelled in the manner aforesaid with the name and address of the seller, and the ingredients thereof be entered, with the name of the person to whom it is sold or delivered, in a book to be kept by the seller for that purpose, and nothing in this Act contained shall repeal or affect any of the provisions of an Act of the Session holden in the fourteenth and fifteenth years in the reign of her present Majesty, intituled ‘An Act to regulate the Sale of Arsenic’ (Clause 17).

SCHEDULE (A).