Part 146

To ensure the successful administration of this class of medicines, the system must be previously prepared for their use by invigorating it, if there is either relaxation or debility; and an opposite course should be pursued when there is an undue degree of arterial action. In the majority of cases, the restoration of the discharge is rather attributable to a proper regulation of the system than to any specific power in the medicine administered.

=EMOLL'IENTS.= _Syn._ EMOLLIENTIA, L. In _pharmacy_ and _therapeutics_, demulcents of an oleaginous, saponaceous, or emulsive character, applied to surfaces (generally external), to soften and relax the fibres. See DEMULCENTS.

=EMUL'SIN.= _Syn._ SYNAPTASE. An azotised substance, forming a large proportion of the white pulp of both bitter and sweet almonds. It is yellowish-white, soluble in cold water, and coagulated by heat and alcohol. Its most remarkable property is its action on amygdalin by which the volatile oil of almonds and hydrocyanic acid, with other products are formed. It has never been obtained in a state of purity.

=EMULSINES.= See EMULSION.

=EMUL'SION.= _Syn._ EMULSIO, L. A milky fluid, formed by the mechanical admixture of oil and water, by means of some other substance that possesses the power of combining with both. The emulsions of the Pharmacop[oe]ia are in the 'British Pharmacop[oe]ia' included in the class _Misturæ_ (which _see_).

In the preparation of emulsions, the oily or resinous ingredients are usually suspended by means of mucilage of gum arabic, almonds, or yolk of egg. 1 dr. of the first, made with equal parts of gum and water; 1 oz. of the second (usually 26 in number); and one in no. of the last, will form 2 dr. of any oil into an emulsion with about 1 oz. of water, gradually added. In some cases, instead of the above substances, a little liquor of potassa is employed, by which a saponaceous emulsion is formed. In all cases the mucilage or other viscid substance should be put into the mortar before anything else. The oil or resinous matter may then be very gradually rubbed in, taking care not to add it more quickly than it can be subdued by the pestle; and if, during this part of the manipulation, the mixture should begin to assume a breaking or curdling appearance at the edges, a few drops of water must be immediately incorporated with it, before adding the remainder of the oil. From the want of this precaution, it is common for an emulsion suddenly to lose its tenacious consistence in the mortar, and it is then in vain to endeavour to restore it. After the oil is thoroughly incorporated, some care is requisite to avoid separating it again by too hasty an effusion of the water or other fluid of the mixture. If any alcoholic or acid liquid is to be added, it must be at the very end of the process. Indeed, the addition of an acid liquid, even a slightly acescent syrup, will often entirely destroy an emulsion. Mixtures of copaiba are frequently spoiled by the addition of spirit of nitric ether; a misfortune which might be avoided by first diluting it with one or two parts of water.

An excellent method of preparing emulsions of resins and gum-resins, is to put the article into a marble or wedgwood mortar, and to pour over it about 4 times its weight of rectified spirit, which is then to be ignited, and the mixture triturated until an equal consistence is obtained. The liquid is then to be added gradually, and the whole patiently triturated or shaken until cold. Yolk of egg or mucilage may be added to the fluid resin or gum-resin, if desired, as in the common method, but an excellent emulsion may be made without them.

The presence of soluble salts in an emulsion is apt to occasion the separation of the oleaginous portion. Spirit produces the same effect in those which are made with yolk or mucilage; and acids in those made with an alkali. The addition of these substances to emulsions should be therefore avoided as much as possible. Emulsions of wax, spermaceti, oil of turpentine, and balsam of copaiba, are the most readily and completely formed with yolk of egg. Volatile oils are more readily made into emulsions if mixed with an equal volume of some simple fixed oil, before proceeding to operate on them. Scammony is generally formed into an emulsion with milk; and resin of jalap, with almonds and water.

In a paper read before the American Pharmaceutical Association by Mr Gregory, the author recommends the use of powdered gum instead of mucilage in the preparation of emulsions. He thinks that three drachms of acacia in fine powder are necessary to emulsify one ounce of any of the volatile oils, and that a little less (about two drachms) will answer for the fixed oils and balsams, and that to this quantity of gum four drachms and a half of water must be added (no more and no less), and that either the water or the oil may be added first to the gum, but it is quickest to add the oil the first; and well triturate before adding the water. Less gum can be made to yield a good result by a careful operator, but, as a general practical working rule, it may be said that three drachms are necessary for one ounce of oil.

The following formulæ, for certain emulsions, are merely given here for examples. Various others will be found under MIXTURE, LOTION, WASH, &c.

=Emulsion of Al'monds.= _Syn._ MILK OF ALMONDS, ALMOND MIXTURE; EMULSIO AMYGDALÆ, MISTURA A., L. _Prep._ 1. Blanched almonds, 1 oz.; beat them to a smooth paste, add, gradually, water, 1/2 pint; and when the whole is thoroughly incorporated, strain through a piece of gauze.

2. As the last, adding sugar, 1 oz.; or syrup (either simple or flavoured), 1-1/2 fl. oz. See EMULSION OF OIL OF ALMONDS (_below_).

=Emulsion of Assaf[oe]t'ida.= _Syn._ EMULSIO ASSAF[OE]TIDÆ, MISTURA A., L. _Prep._ (Duclow.) Assaf[oe]tida, 1 oz.; powdered gum, 2 oz.; oil of almonds, 3-1/2 fl. oz.; water, 6 fl. oz. Antispasmodic.--_Dose_, 1 to 2 table-spoonfuls; in hysterical affections, &c.

=Emulsion of Cam'phor.= _Syn._ EMULSIO CAMPHORÆ, E. CAMPHORATA, MISTURA CAMPHORÆ (Ph. E.), L. _Prep._ 1. (Ph. Castr. Ruth. 1840.) Camphor, 1/2 dr.; triturate with milk, 1/2 fl. oz., gradually added; then further add of water, 7-1/2 fl. oz.

2. (Ph. E.) Camphor, 20 gr.; lump sugar, 1/2 oz.; triturate together, and add of blanched almonds, 1/2 oz.; again triturate, then gradually add of water, 1 pint. Stimulant, antispasmodic, and diaphoretic.--_Dose_, 1 fl. oz. to 2 fl. oz.

=Emulsion of Cas'tor Oil.= _Syn._ EMULSIO OLEI RICINI, MISTURA O. R., L. _Prep._ 1. Castor oil, 1 oz.; thick mucilage, 1-1/2 oz.; syrup of orange peel, 1 fl. oz.; water, 6 fl. oz.

2. As the last, but using milk instead of water.--_Dose._ One third; as an aperient for females who object to taking the unprepared oil.

=Emulsion of Copai'ba.= _Syn._ EMULSION OF CAPIVI; EMULSIO COPAIBÆ, MISTURA C., L. _Prep._ 1. Balsam of copaiba and syrup of orange peel, of each 2 oz.; yolks of 5 eggs; milk, 14 fl. oz.

2. (Beral.) Copaiba and mucilage, of each 2 oz.; water, 12 fl. oz.--_Dose_, 1/2 oz. to 1 oz., 2 or 3 times a day; where the use of copaiba is indicated.

=Emulsion of Cubebs.= _Syn._ EMULSIO CUBEBÆ. (Dublanc.) _Prep._ Essence of Cubebs, 4 oz.; mucilage, 4 oz. Mix them.

=Emulsion of Gum.= _Syn._ EMULSIO ACACIÆ, MISTURA ACACIÆ (Ph. E.), L. _Prep._ From sweet almonds (blanched), 10 dr.; white sugar, 5 dr.; mucilage, 3 fl. oz.; water, 1 quart. Demulcent. In coughs, &c., _ad libitum_.

=Emulsion of Indian Hemp.= _Syn._ EMULSIO CANNABIS INDICÆ. (Mr Bromfield.) _Prep._ Rub 1 scruple of extract of Indian hemp in warm water with 1 fl. dr. of olive oil; then add gradually, still triturating the mixture, 4 dr. of mucilage of acacia and 7-1/2 oz. of distilled water.

=Emulsion of Oil of Almonds.= _Syn._ EMULSIO OLEI AMYGDALÆ, L. _Prep._ From oil of almonds, 3 dr.; thick mucilage and simple syrup, of each, 5 dr.; rose water, 1 fl. oz.; distilled water, 3 to 4 fl. oz. An elegant and efficient substitute for almond milk. See EMULSION OF ALMONDS (_above_).

=Emulsion, Pancreatic.= See PANCREATIN.

=Emulsion of Peru'vian Balsam.= _Syn._ EMULSIO BALSAMICA, E. BALSAMI PERUVIANI, L. _Prep._ 1. As emulsion of copaiba.

2. (Hosp. F.) Balsam of Peru, 1/2 oz.; oil of almonds, 6 dr.; powdered gum, 1 oz.; triturate together, and add, gradually, rose water, 4 fl. oz.--_Dose_, 1 or 2 table-spoonfuls; in old asthmas, chronic coughs, winter coughs, &c.

=Emulsion of Poppies.= _Syn._ EMULSIO PAPAVEUS. _Prep._ Poppy seeds, 2 drachms; water, 8 oz. Make into an emulsion and strain.

=Emulsion of Raw Meat.= (Yvon.) Raw meat 250 grammes; sweet almonds, 75 grammes; bitter almonds, 5 grammes; white sugar, 80 grammes. After blanching the almonds beat them up with the rest of the ingredients in a marble mortar until a rose-coloured uniform paste is obtained. This may be easily made into an emulsion with water, and will not unmix for 24 hours. It can be made still more nourishing by the addition of the yolks of two eggs, and by the substitution of milk for water. This emulsion is frequently prescribed by continental physicians.

=Emulsion of Resin of Jalap.= _Syn._ EMULSIO PURGANS CUM RESINÆ JALAPÆ. (Par. Pharm.) _Prep._ Resin of jalap, 8 gr.; white sugar, 1 oz.; orange-flower water, 2 dr.; water, 4 oz. Triturate the resin with a little of the sugar, add gradually half the yolk of an egg, triturate for a long time, then add gradually the rest of the sugar and the water.

=Emulsion of Scam'mony.= _Syn._ EMULSIO SCAMMONII, MISTURA S. (Ph. E.), L. _Prep._ 1. (Ph. E.) Resin of scammony, 7 gr.; new milk, 3 fl. oz. For a dose.

2. (Planche.) Aleppo scammony, 7 gr.; sugar, 2 dr.; new milk, 3 fl. oz.; cherry-laurel water, 5 drops. For a dose. Purgative; in torpor of the intestines, dropsy, worms, &c. The formula of the Paris Codex is similar.

=Emulsion of Spermace'ti.= _Syn._ EMULSIO CETACEI, MISTURA C., L. _Prep._ As emulsion of wax. Demulcent.

=Emulsion of Tur'pentine.= _Syn._ EMULSIO TEREBINTHINÆ, MISTURA T., L. _Prep._ 1. Chio turpentine, 2 dr.; white sugar, 1 oz.; yolk of 1 egg; milk of almonds, 4 fl. oz. In gleets.--_Dose_, 2 table-spoonfuls, 3 or 4 times a day.

2. (Clossius.) Venice turpentine, 1-1/2 dr.; yolk of 1 egg; peppermint water, 4-1/2 fl. oz. (See _below_.)

=Emulsion of Oil of Turpentine.= _Syn._ EMULSIO OLEI TEREBINTHINÆ, MISTURA O. T., L. _Prep._ (Carmichael.) Rectified oil of turpentine, 1 fl. oz.; yolk of 2 eggs; emulsion of almonds, 4 fl. oz.; syrup of orange peel, 2 fl. oz.; spirit of lavender, 4 fl. dr.; oil of cinnamon, 5 or 6 drops.--_Dose_, 1 fl. oz., twice or thrice a day; in nephritic pains, and that variety of ophthalmia termed iriditis. (See _above_.)

=Emulsion of Wax.= _Syn._ EMULSIO CERÆ, E. CERÆ ALBÆ, MISTURA C., LAC C., L. _Prep._ (Guibourt.) White wax, 1 oz.; powdered gum, 1-1/2 dr.; water, 24 fl. oz.; simple syrup, 4 fl. oz.; put the syrup and gum into a warm mortar, add the wax, and triturate with a warm pestle until united; then add the water (warm) gradually, and continue the agitation till the whole is quite cold. Demulcent. _Ad libitum._

=ENAM'EL.= A species of vitreous varnish, coloured with metallic oxides, applied in a thin stratum to brightly polished metallic surfaces (copper or gold), on which it is fused by the flame of a lamp urged by the blowpipe, or by the heat of a small furnace.

The basis of all enamels is a highly transparent and fusible gloss, called 'frit,' 'flux,' or 'paste,' which readily receives a colour on the addition of metallic oxides. It may be made by one or other of the following formulæ:

_Prep._ 1. Red lead, 16 parts; calcined borax, 3 parts; powdered flint glass, 12 parts; powdered flints, 4 parts; fuse in a Hessian crucible for 12 hours, then pour it out into water, and reduce it to a powder in a biscuit-ware mortar.

2. Tin, 3 parts; lead, 10 parts; mix, calcine in an iron pot at a dull cherry-red heat, and scrape off the oxide as it forms, observing to obtain it quite free from undecomposed metal; then reduce it to fine powder by grinding and elutriation. In this state it is known among enamellers as 'flux' or 'calcine.' 4 parts of this 'calcine' are next mixed with an equal weight of pure sand or powdered flints, and 1 part of sea salt, or other alkaline matter; the mixture is then partially fused in a Hessian crucible, by which it undergoes semi-vitrification.

3. (Chaptal.) Lead and tin, equal parts; calcine as above, and take off the mixed oxides or 'calcine' and ground flints, of each, 1 part; pure carbonate of potash, 2 parts; and proceed as before.

4. (Wynn.) Flint glass, 3 oz.; red lead, 1 oz.; as last.

5. (Wynn.) Red lead, 18 parts; borax (not calcined), 11 parts; flint glass, 16 parts; as last.

6. (Wynn.) Powdered flints, 10 parts; nitre and white arsenic, of each, 1 part; as last.

_Obs._ The precise qualities of the products of the above processes depend greatly upon the duration and degree of heat employed. By increasing the quantity of sand, glass, or flux, the enamel is rendered more fusible, and the opacity and whiteness is increased by the addition of oxide of tin. The use of borax should be avoided, or it should be used sparingly, as it is apt to make the enamel effloresce and lose colour.

=Enamel, Black.= _Prep._ 1. Calcined iron (protoxide), 12 parts; oxide of cobalt, 1 part; mix, add an equal weight of white flux, and fuse as before.

2. (Clouet.) Pure clay, 3 parts; protoxide of iron, 1 part. A fine black.

3. Peroxide of manganese, 3 parts; zaffre, 1 part; mix, and add it, as required, to white flux.

=Enamel, Blue.= _Prep._ 1. White 'frit' or 'flux,' coloured with oxide of cobalt.

2. Sand, red lead, and nitre, of each 10 parts; flint glass or ground flints, 20 parts; oxide of cobalt, 1 part, more or less; depending on the desired depth of colour.

=Enamel, Brown.= _Prep._ 1. Manganese, 5 parts; red lead, 16 parts; flint powder, 8 parts; as before.

2. (Wynn.) Manganese, 9 parts; red lead, 34 parts; flint powder, 16 parts.

3. Red lead and calcined iron, of each, 1 part; antimony, litharge, and sand, of each, 2 parts. To be added in any required proportion to white 'frit,' according to the colour desired. A little oxide of cobalt or zaffre is frequently added to alter the shade.

=Enamel, Green.= _Prep._ 1. 'Flux' or 'frit,' 2 lbs.; black oxide of copper, 1 oz.; as before.

2. As the last, but adding red oxide of iron, 1/2 dr. Less decisive.

3. Copper dust and litharge, of each 2 oz.; nitre, 1 oz.; sand, 4 oz.; 'flux' or 'frit,' q. s.

4. From transparent 'frit,' any quantity; oxide of chromium, q. s. to colour. Colour superb; it will stand a great heat; in common hands, however, it frequently turns on the dead-leaf tinge.

5. Transparent 'flux,' 5 oz.; black oxide of copper, 20 to 40 gr.; oxide of chromium, 2 gr. Resembles the emerald.

6. From blue and yellow enamel mixed in the required proportions.

=Enamel, Ol'ive.= _Prep._ Blue enamel, 2 parts; black and yellow enamel, of each, 1 part. See ENAMEL BROWN.

=Enamel, Or'ange.= _Prep._ 1. Red lead, 12 parts; red sulphate of iron and oxide of antimony, of each, 1 part; flint powder, 3 parts; calcine together, powder, and melt with 'flux,' 50 parts.

2. (Wynn.) Red lead, 12 parts; oxide of antimony, 4 parts; flint powder, 3 parts; red sulphate of iron, 1 part; calcine, then add 'flux,' 5 parts, to every 2 parts of this mixture.

=Enamel, Pur'ple.= _Prep._ 1. 'Flux' or 'frit,' coloured with oxide of gold, purple precipitate of cassius, or peroxide of manganese.

2. Sulphur, nitre, green vitriol, antimony, and oxide of tin, of each, 1 lb.; red lead, 60 lb.; mix, fuse, cool, powder, and add rose copper (red oxide), 19 oz.; zaffre, 1 oz.; crocus martis, 1-1/2 oz.; borax, 3 oz.; and of a compound formed of gold, silver, and mercury, 1 lb.; fuse, stirring the melted mass with a copper rod all the time, then place it in crucibles, and submit them to the action of a reverberatory furnace for 24 hours. This is said to be the purple enamel used in the mosaic pictures in St. Peter's at Rome.

=Enamel, Red.= _Prep._ 1. 'Paste' or 'flux,' coloured with the red oxide or protoxide of copper. Should the colour pass into the green or brown, from the partial peroxidation of the copper, from the heat being raised too high, the red colour may be restored by the addition of any carbonaceous matter, as tallow, or charcoal.

2. By tinging the glass or 'flux' with the oxide or salts of gold, or with the purple precipitate of cassius. These substances produce shades of red, inclining to crimson or purple of the most exquisite hue. The enamel often comes from the fire quite colourless, and afterwards receives its rich hue at the lamp.

3. (Wynn.) Sulphate of iron (calcined dark), 1 part; a mixture of 6 parts of 'flux' (No. 5), and 1 of colcothar, 3 parts. Dark red.

4. (Wynn.) Red sulphate of iron, 2 parts; 'flux' (No. 1), 6 parts; white lead, 3 parts. Light red.

=Enamel, Rose-col'oured.= _Prep._ Purple enamel (or its elements), 3 parts; 'flux,' 90 parts; mix, and add silver leaf or oxide of silver, 1 part, or less.

=Enamel, Transpa''rent.= The 'frit' or 'flux' described _above_.

=Enamel, Vi'olet.= _Prop._ 1. Purple enamel, 2 parts; red enamel (No. 2), 3 parts; 'frit,' 6 parts.

2. Saline or alkaline 'frit' or 'flux,' any quantity; peroxide of manganese, q. s. to colour. As the tint depends on the metal being at the maximum of oxidation, contact with oily or carbonaceous substances should be particularly avoided.

=Enamel, White.= _Prep._ 1. 'Calcine' (from 2 parts of tin and 1 part of lead), 1 part; fine crystal glass or 'frit,' 2 parts; manganese, a few grains; powder, mix, melt, and pour the fused mass into clean water; again powder, and fuse, and repeat the whole process 3 or 4 times, avoiding contamination with smoke, dirt, or oxide of iron. A fine dead white.

2. Washed diaphoretic antimony, 1 part; fine glass (free from lead), 3 parts; mix, and proceed as before. Very fine.

3. Lead, 30 parts; tin, 33 parts; calcine as before, then fuse 50 parts of this 'calcine' with an equal weight of flints, in powder, and 100 parts of salt of tartar. A fine dead white enamel.

_Obs._ For white enamel, the articles must be perfectly free from foreign admixture, as this would impart a colour. When well managed, either of the above forms will produce a paste that will rival the OPAL.

=Enamel, Yellow.= Superior yellow enamels are less easily produced than those of most other colours; they require very little flux, and that mostly of a metallic nature. The following come highly recommended by experienced artists:--

_Prep._ 1. From 'frit' or 'flux,' fused with oxide of lead, and a little red oxide of iron.

2. Lead, tin, ashes, litharge, antimony, and sand, of each 1 oz.; nitre, 4 oz.; mix, fuse, and powder; and add the product to 'flux' or 'frit,' q. s.

3. White oxide of antimony, alum, and sal-ammoniac, of each 1 part; pure carbonate of lead, 1 to 3 parts, or q. s. (all in powder); mix, and expose them to a heat sufficiently high to decompose the sal-ammoniac. Used as the last. Very bright coloured.

4. (Wynn.) Red lead, 8 oz.; oxide of antimony, and tin, calcined together, of each 1 oz; mix, and add of 'flux' (No. 5), 15 oz.; mix well and fuse.

5. Pure oxide of silver added to the metallic 'fluxes.' The salts of silver are also used, but are more difficult to manage. If a thin film of oxide of silver be spread over the surface of the enamel to be coloured, exposed to a moderate heat, then withdrawn, and the film of reduced silver on the surface removed, the part under will be found tinged of a fine yellow. (Clouet.)

=Enamelling of Cast-Iron.= Wagner in his 'Chemical Technology' gives the following account of this process:--The surface of the cast-iron to be enamelled is first carefully cleaned by scouring with sand and dilute sulphuric acid, next a somewhat thickish magma, made of pulverised quartz, borax, feldspar, kaolin and water is brushed over the clean metallic surface as evenly as possible, and immediately after a finely powdered mixture of feldspar, soda, borax, and oxide of tin, is dusted over, after which the enamel is burnt in by the heat of a muffle. In France an enamel is applied which consists of 130 parts of flint glass, 20-1/2 parts of carbonate of soda, and 12 parts of boric acid fused together, and afterwards ground to a fine powder.

It would appear, however, from the statements contained in a paper read by Mr Tatlock, F.R.S.E., F.C.S., that the enamel used for iron vessels is frequently of a less harmless kind than that described by Wagner. Mr Tatlock states that in some instances the milk-white porcelainous enamel, with which cast-iron cooking vessels are now so commonly prepared, has a composition such as to render it highly objectionable, on account of the facility with which it is acted upon by acid, fruits, common salt, and other ordinary dietetic substances, by which means lead, and even arsenic, are dissolved out in large quantity during cooking processes.

Mr Tatlock gives the analysis of three samples of enamel from the interior of three cast-iron pots obtained from different manufacturers. These iron vessels were all employed for cooking:--

No. 1. No. 2. No 3. per cent. per cent. per cent.

Silica 61·00 42·40 42·00 Alumina 8·00 2·88 6·06 Oxide of iron 1·10 2·04 4·04 Lime 3·02 0·16 0·78 Magnesia 0·28 0·10 0·21 Oxide of lead absent 25·89 18·48 Potash 5·61 7·99 6·46 Soda 20·67 14·67 19·25 Phosphoric acid trace trace trace Arsenious acid 0·02 0·42 1·02 Carbonic acid 0·30 absent absent Borax absent 3·45 1·70 ------- ------- ------- 100·00 100·00 100·00 ------- ------- ------- Total bases 38·58 53·73 55·28

The author showed that it was not so much on account of the presence of large proportions of lead and arsenic that the enamels are so dangerous, but because they are so highly basic in character, that they are acted upon with facility by feebly acid solutions, the lead and arsenic being thereby easily dissolved out.

He demonstrated that the ratio of the bases to the silica in No. 1 was 1 to 1·58; in the No. 2, as 1 to 0·79; and in the No. 3, as 1 to 0·76. A one per cent. solution of citric acid boiled in the No. 1 did not affect it in the slightest, while in the case of the No. 3, the glassy surface of the enamel was at once roughened and destroyed, and lead dissolved out to such an extent as to give immediately a dense black precipitate with sulphuretted hydrogen. He thought that no enamel was fit to be used unless it were totally unaffected by boiling with a one per cent. solution of citric acid, which was a very moderate test, and gave it as his opinion that either the use of such poisonous ingredients as lead and arsenic in large quantity should be entirely abandoned, or that the composition otherwise of the enamel should be of such a character as to ensure that none of the poisonous substances could be dissolved out, in the circumstances under which the enamelled vessels are used.

=ENCAU'STIC.= See PAINTING (Encaustic).

=ENDEMIC.= Indigenous. Peculiar to a district. Those are called endemic diseases, which are produced by causes more or less local. The word is often confounded with epidemic.

=ENE'MA.= _Syn._ CLYSTER; EN'EMA (pl. ENEM'ATA), L. A medicine, usually liquid (sometimes gaseous), thrown into the rectum or lower bowels.