Part 8

(_a_) Wide-mouthed flask, containing the sample for examination, hermetically stopped by the cork (_e_) and supporting the tubes (_b_) and (_c_). (_b_) Bulbous tube, containing fragments of fused chloride of calcium, terminating in a capillary tube (_g_). (_c_) Bent tube, reaching nearly to the bottom of the flask (_a_). (_d_) Small tube containing bicarbonate of soda. (_e_) Cork fitting bottle (_a_), and the tubes (_b_) and (_c_), hermetically. (_f_) Silken thread, suspending the small tube (_d_).]

The two above methods of estimating the amount of acid are only superior to the generally used methods first described, when the presence of colouring matter interferes with the reaction of the litmus used to show the point of neutralisation.

_Observations._ When great accuracy is required in conducting the neutralisation of the solution in estimating volumetrically with litmus as an indicator, it is proper to prepare and keep standard solutions of sulphuric acid and oxalic acid, with which occasionally to try the alkaline test-liquor. The only difficulty in the process is to avoid over-saturation of the acid-sample. Great care must be taken not to exceed the precise point of neutralisation of the acid. After adding each portion of the test-liquor, the solution should be well stirred up, and as soon as the effervescence becomes languid the greatest caution must be observed in adding more. The proper point is arrived at when the liquor ceases to redden litmus, and does not alter the colour of turmeric paper; if it turns the latter brown, too much of the test-liquid has been added, and the operation becomes useless. Towards the end of the experiment, when great precision is required, a gentle heat may be applied, in order to expel the free carbonic acid in the liquor; but otherwise this is unnecessary. The peculiar soapy odour gradually acquired by the liquor as it nears saturation will materially assist the operator when testing vinegars, and some of the other vegetable acids. A good method is to tint either the acid-sample or the test-liquid with a few drops of litmus, as noticed under ACETIMETRY; when the reddish shade will gradually deepen into 'purple,' or the purple into 'red,' as the point of saturation is approached; and the blue colour will be perfectly restored as soon as this point is reached. Dr Ure recommends keeping the ammonia-test ready tinged with litmus, and the same applies to other test-liquors.

In commerce, the strength of acids is frequently reckoned with reference to a standard, termed 100 acidimetric degrees. This is taken from the circumstance that 91 gr. of commercial oil of vitriol, of a sp. gr. of 1·845, exactly saturate 100 gr. of dried carbonate of soda. An acid requiring only 35, 50, or any other number of grains of the carbonate to saturate it, is in like manner termed of so many degrees strong; the number of grains representing in each case an equal number of degrees. This method originated with the French chemists, and though only conventional, and principally confined to commercial purposes, is especially adapted to practical men but little conversant with chemistry, yet very ready in retaining or calculating anything on the centesimal scale, from its similarity to monetary language and reckoning.

=ACID'ITY.= _Syn._ ACID'ITAS, L.; ACIDITÉ, Fr.; SÄURE, Ger. In _chemistry_, the state of being acid. In _physiology_, &c., the impression given to the organs of taste by tart or acid substances. Sourness. See FERMENTATION, MALT-LIQUORS, WINES, &c.

=Gas'tric Acidity.= Acidity of the stomach; a common and well-known symptom of weak or disordered digestion.

_Treat., &c._ Small doses of absorbents or antacids, three or four times daily, to which some tonic bitter, as calumba, cascarilla, chamomile, gentian, or orange-peel, may be added. Stomachic stimulants, as capsicum, ginger, mustard, or wine, &c., taken with, or after, meals, are also useful. The diet should be light and nutritious; and acescent vegetables, over-ripe fruit, and weak new beer or other liquors avoided as much as possible. The bowels should be kept regular, but not open, by the occasional use of mild aperients, as rhubarb, aloes, castor oil, senna, or mercurial pill, or compounds containing them. Excessive looseness or diarrh[oe]a may be checked by a few doses of carbonate of soda, chalk-mixture, or astringents.

In INFANCY this affection is usually accompanied by restlessness, continual crying, drawing up of the legs forcibly towards the body, hiccups, vomiting, diarrh[oe]a, sour eructations, griping pains, green stools, and debility; often followed, when the irritation is considerable, by convulsions. The treatment consists in relieving the bowels of all offending matter by a few doses of rhubarb-and-magnesia. The looseness or diarrh[oe]a may be checked by a few small doses of carbonate of soda or chalk mixture; or better, in an infant which is fed by lime-water (1 or 2 fl. oz.) mixed with as much milk. Two or three drops of caraway, cinnamon, dill, or peppermint water, on sugar (not with the food) will tend to promote the expulsion, and prevent the undue generation of gases. The flatulence usually disappears with the acidity. The occasional administration of 1 to 3 gr. of quicksilver-with-chalk ('grey powder'), will frequently remove the complaint, and prevent its recurrence, when all other means fail. The diet of both nurse and infant should be carefully regulated.

See ANTACIDS, DYSPEPSIA, &c.

_Treatment for Horses._ Alkalies, their carbonates and bicarbonates; alterative doses of aloes with alkalies; chalk, carbonate of magnesia; mineral acids; bismuth, arsenic, nux vomica, or strychnia.

=ACIDS, EFFECTS OF, ON VEGETATION.= This subject has been ably investigated of recent years by Dr Angus Smith and Mr Rothwell, and the practical importance of their labours is shown by the circumstance that an Act of Parliament passed in 1875 renders it penal for the proprietors of alkali works to condense not less than 95 per cent. of the hydrochloric acid evolved in the process of manufacturing 'soda,' also to allow air, smoke, or chimney gases to escape into the atmosphere containing more than one fifth of a grain of hydrochloric acid per cubic foot. Every owner of an alkali work is likewise required to 'use the best practical means of preventing the discharge into the atmosphere of all other noxious gases arising from such work, or of rendering such gases harmless when discharged.'

The injurious effects of acids on vegetation are indicated chiefly by the shrivelled-up appearance which the leaves of herbage, trees, &c., exhibit in the vicinity of chemical works in which the condensation of noxious gases (hydrochloric acid, sulphurous acid, sulphuric acid, sulphuretted hydrogen, nitric acid, and oxides of nitrogen and chlorine) is not effectually carried out. According to Mr Rothwell, 'in fields exposed to acid vapours handfuls of dead grass may be pulled up in the spring, smelling strongly of the vapour, and that trees, under similar influences, become bark-bound.'

The following is a list of trees arranged in the order of their susceptibility. (Rothwell.)

_Forest Trees._ Larch, spruce fir, Scotch fir, black Italian poplar, Lombardy poplar, ash, oak, elm, birch, alder, sycamore.

_Fruit Trees._ Damson, greengage, Halewood plum, Jacob plum, pears, apples, cherries.

_Shrubs, Evergreens, and Wild Plants._ British laurels, Portugal laurels, _Aucuba_ _Japonica_, Barberry evergreen, hazel, guelder rose, sloe thorn, hawthorn, raspberries, gooseberries, blackberries, gorse, hollies.

_Farm Crops._ Potatoes, mangel, white clover and rhubarb, red clover, trefoil, rye-grass, wheat, oats, barley, common turnips, swedes.

_Second list of Plants affected by Noxious Vapours, mixing the classes according to the effects produced on each._

I. Fern--only in the summer.

Scotch firs, spruce, and larches--a little in winter.

Clover (white and red), trefoil, rye-grass, poplars, hawthorn, potatoes--receive damage in winter to roots.

II. Wheat receives some damage in winter.

Oats in May, when in the grass state, soon receive damage.

Barley, mangel, common turnips, rhubarb.

III. Laurels (British and Portugal), aucubas, yews, holly, gorse--receive damage in winter, but more in summer.

Old grass meadows and pastures receive much damage in winter.

IV. Ashes, oaks, hazels, horse-chestnuts, walnuts, Spanish chestnuts, sloe thorn.

V. Swedish turnip and cabbages, damson, other fruit trees, beech, elm, birch, alder, sycamores.

=ACIDULÆ.= [L. pl.] In _medicine_, mineral waters rich in carbonic acid.

=ACIDULATED=. _Syn_. ACIDULATUS, L.; ACIDULÉ, Fr. Blended or flavoured with an acid; made slightly sour. See KALI (Acidulated), DROPS, LOZENGES, &c. In _chemistry_, the addition of an acid to a neutral or alkaline liquid until it reddens blue litmus paper.

=ACIDUM.= [L.] An acid.

=ACNE.= [_Syn._ PIMPLED FACE.] There are two forms of this affection. 1st. In young persons of both sexes; generally in phlegmatic habits. The disease shows itself by hard pimples, with a small black spot on the apex, unaccompanied with redness or inflammation at first, but after a while they become red and inflamed, and sometimes suppurate, with a greasy look of the skin between them. In this form of acne the black spots should be picked out with a needle or a small pair of tweezers. A long piece of thick matter, like a worm, is extracted; but is no worm. Afterwards wash the face with water in which a small piece of Quillar bark has been steeped, or with bitter almond emulsion, or borax, one drachm, water 4 oz. When there is no inflammation, use Eau de Cologne, or a few drops of oil of rosemary dissolved in spirit of wine, taking a small dose of magnesia in the morning, or milk of sulphur daily. When the pimples are very sluggish the cautious application of tincture of iodine, or of ointment of nitrate of mercury, will be found serviceable.

2nd. Arises from intemperance. In this case a gradual change of habits is essential. The use of soap should be avoided, and recourse had to warm fomentations of slippery elm, or thin oat gruel. The following should be applied to the pimples:--Cold cream, 1 oz., Goulard's extract 20 drops, mixed together; or lemon juice diluted, or solution of borax in water. The internal administration of the mineral acids combined with bitter tonics, or small doses of iodide of potassium, will be found effectual.

_Treatment._ Fomentations, poultices, chloride of zinc solution externally; sulphur and alteratives internally.

=ACOLOGY=. _Syn._ In _medicine_, the doctrine of, or a discourse on, remedies or the materia medica.

=ACONITE.= (-nite). _Syn._ ACON'ITUM, L.; ACONIT, Fr.: AKONITUM, EISENHUT, STURMHUT, Ger. Monkshood; wolfsbane. In _botany_, a genus of exogenous plants. _Nat. ord._, Ranunculaceæ; _Sex. syst._, Polyandria Trigynia. They are characterised by showy purple or yellow helmet-shaped flowers growing in panicles, deeply cut leaves, and perennial (usually) tap-shaped or tapering roots. The whole plant is highly poisonous, the roots being more poisonous than the leaves. In _medicine_ and _materia medica_, the plant Aconitum Napellus (which _see_).

_Symptoms._ Numbness and tingling in the mouth and throat, which are parched; followed by giddiness, dimness of sight, and (sometimes) delirium, but seldom complete coma; there is numbness and tingling of the limbs, a loss of power in the legs, (in some cases) frothing at the mouth, severe abdominal pains, nausea, vomiting, and diarrh[oe]a; tremors or twitchings of the voluntary muscles, (sometimes) convulsions (in animals, but not in man); sharp cries; pupil (generally) dilated, very rarely contracted; pulse fitful and sinking; skin cold and livid; difficulty of breathing; general prostration; loss of sensation or feeling, insensibility, general trembling, fainting, and sudden death. The eyes are often glaring; and, in some cases, the patient is completely paralysed, yet retains consciousness to the last. The case generally proves fatal in from 1 to 8 hours. If it last beyond this period there is hope of recovery. (Fleming.)

_Antidotes._ Ammonia, or brandy, with artificial respiration if necessary: cold affusion and friction, with warm towels to the back and limbs. See ALKALOIDS.

=ACONITE LEAVES= (B. Ph.). _Syn._ ACONITI FOLIA, L. The fresh leaves and flowering tops of _aconitum napellus_, Linn., gathered when about one third of the flowers are expanded, from plants cultivated in Britain.

_Char._ Leaves smooth, palmate, divided into five deeply cut wedge-shaped segments; excizing slowly, when chewed, a sensation of tingling. Flowers numerous, irregular, deep blue, in dense racemes.

_Prep._ Extractum aconiti.

=ACONITE ROOT.= (B. Ph.). _Syn._ ACONITI RADIX, L. The dried root of _aconitum napellus_. Imported from Germany, or cultivated in Britain, and collected in the winter or early spring before the leaves have appeared.

_Prep._ Aconitia, the active principle; Linimentum Aconiti, 1 ounce to 1 fluid ounce; Tinctura Aconiti, 54-1/2 grains to 1 fluid ounce.

_Char._ Usually from one to three inches long, not thicker than the finger at the crown, tapering, blackish-brown, internally whitish. A _minute_ portion, cautiously chewed, causes prolonged tingling and numbness.

=ACONITI FOLIA.= See ACONITE LEAVES.

=ACONITI RADIX.= See ACONITE ROOT.

=ACONITIA.= C_{30}H_{47}O_{7}N. (B. P.) _Syn._ ACONITIA, L. An alkaloid obtained from aconite.

Take of Aconite root, in coarse powder, 14 pounds. Rectified spirit } Distilled water } of each Solution or ammonia } a sufficiency. Pure ether } Diluted sulphuric acid}

Pour upon the aconite root three gallons of the spirit, mix them well, and heat until ebullition commences; then cool and macerate for four days. Transfer the whole to a displacement apparatus, and percolate, adding more spirit, when requisite, until the root is exhausted. Distil off the greater part of the spirit from the tincture, and evaporate the remainder over a water bath until the whole of the alcohol has been dissipated. Mix the residual extract thoroughly with twice its weight of boiling distilled water, and when it has cooled to the temperature of the atmosphere, filter through paper. To the filtered liquid add solution of ammonia in slight excess, and heat them gently over a water bath. Separate the precipitate on a filter, and dry it. Reduce this to coarse powder, and macerate it in successive portions of the pure ether with frequent agitation. Decant the several products, mix and distil off the ether until the extract is dry. Dissolve the dry extract in warm distilled water acidulated with the sulphuric acid; and, when the solution is cold, precipitate it by the cautious addition of solution of ammonia diluted with four times its bulk of distilled water. Wash the precipitate on a filter with a small quantity of cold distilled water, and dry it by slight pressure between folds of filtering paper.

_Characters and Tests._ A white, usually amorphous, solid, soluble in 150 parts of cold, and 50 of hot water, and much more soluble in alcohol and in ether; strongly alkaline to reddened litmus, neutralising acids, and precipitated from them by the caustic alkalies, but not by carbonate of ammonia or the bicarbonates of soda or potash. It melts with heat, and burns with a smoky flame, leaving no residue when burned with free access of air. When rubbed on the skin it causes a tingling sensation, followed by prolonged numbness. It is a very active poison.

=ACONITIA, CRYSTALLISED.= C_{27}H_{40}NO_{10}. Exhaust the root of wild aconite, carefully picked and powdered, with very strong alcohol, to which 1 per cent. of tartaric acid has been added. Distil at a gentle heat, and sheltered from the air, to recover the alcohol. Treat the extract with water to separate all the fatty and resinous matters. The solution which contains the aconite in the state of acid tartrate is first shaken with ether to remove colouring matters, and then the alkaloid is set free by the addition of alkaline bicarbonate, until the cessation of effervescence. A fresh treatment with ether of this alkaline solution removes the alkaloid, which crystallizes upon the concentration of the ethereal liquid, with an addition of petroleum spirit. The crystals are colourless tables, rhombic or hexagonal, according to the modifications produced principally in the acute angles. Crystallized aconitia is soluble in alcohol, ether, benzine, and chloroform; insoluble in petroleum oils and glycerine.

ACONITIA NITRATE, CRYSTALLISED. Crystallised aconitine q. s.; nitric acid, sp. gr. 1·442, q. s. Saturate the nitric acid with the aconitine and evaporate. Voluminous crystals are easily obtained (from 'Formulæ for New Medicaments adopted by the Paris Pharmaceutical Society').--'Pharm. Journal.' Owing to the decomposition which this alkaloid undergoes in the animal organism, as well as to its liability to decompose during the process of evaporation, and exposure to the air, it often becomes extremely difficult, if not impossible, to obtain it in a separate state in conducting a _post-mortem_ examination. The physiological effects seem to furnish the most prominent and characteristic evidence of its presence in such cases, or at any rate these may serve as a valuable guide to the toxicologist.

Uncrystallised aconitia is sometimes contaminated with delphinia, as well as with aconella, another constituent of aconite root. For the dissection of these see ALKALOIDS. One fiftieth of a grain of aconitia is stated to have killed a dog.

_Antidotes._ See ACONITE.

=ACONITIC ACID.= (Identical with _Pyrocitric Acid_.) An acid extracted by Peschier from _aconitum napellus_, and by Bracconnot from _equisetum fluviatile_. It exists in these plants chiefly in the form of aconitate of calcium.

_Properties._ A white, colourless, semi-crystalline mass.

=ACONITINA.= See ACONITIA.

=ACONITINE.= See ACONITIA.

=ACONI'TUM.= [L.] Aconite. The pharmacop[oe]ial name of _aconitum napellus_(see _below_).

=Aconitum Ferox.= (Ind. P.) _Habitat_. Temperate and sub-Alpine Himalaya, at 10,000 to 14,000 feet elevation, from Gurhwal to Sikkim.

_Officinal part._ The dried root (_Aconiti ferocis Radix_), in common with those of other Himalayan species, viz., _aconitum napellus_, _a. palmatum_, and _a. luridum_, constitutes the drug well known in the bazaars of Upper India under the Hindostani name of _Bish_ or _Bikh_.

It occurs in the form of tuberous roots of a more or less conical form, from two to three inches in length, and from half an inch to one inch in thickness at their upper end. They have usually a shrunken appearance, and are covered with a dark shrivelled bark; fracture shining and resinous; sometimes waxy, varying in colour from pale to deep brown. Some specimens are white and spongy; and these, it is asserted, are superior in activity to the more compact kinds. Inodorous; taste at first slightly bitter, leaving a peculiar sense of numbness on the tongue and fauces. Active principle, aconitia.

_Medical Properties and Uses._ Similar to those of _aconitum napellus_ of Europe. _Preparations._ This root may be advantageously used for the manufacture of aconitia, the proportion of this alkaloid being much larger than in the European drug; and also for the preparation of Linimentum Aconiti. From its greater activity, however, it is unsuited for the preparation of this tincture, which is intended for external use.

=Aconitum Hetorophyllum.= (Ind. P.) _Habitat_. Western temperate Himalaya, at 8000 to 13,000 feet elevation; from Indus to Kumaon. _Officinal part._ The dried root (_Aconiti heterophylli Radix_). Ovoid tuberous roots, tapering downwards to a point, from one to one and a half inches or more in length, and from three eighths to half an inch in thickness. The surface, which is covered with a thin greyish epidermis, is slightly wrinkled longitudinally, and marked here and there with root scars. It is inodorous, and of a bitter taste, devoid of acridity. Does not contain aconitia. It may be readily distinguished from other roots sold in the bazaars under the same vernacular name (Atis) by its characteristic bitterness. _Properties._ Tonic and antiperiodic. It may be administered internally with safety, as it contains no poisonous principle. _Therapeutic uses_. In convalescence after debilitating diseases, and in intermittent and other paroxysmal fevers, it has been found an efficient remedy. _Doses._ Tonic, 5 to 10 grains thrice daily; antiperiodic, 20 to 30 grains of the powdered root every three or four hours, irrespective of the presence of pyrexia.

=Aconitum Napell'us.= [Linn.] _Syn._ ACONI'TUM, Ph. L., E., & D.; ACONITNAPÈL, CHAPERON DE MOINE, Fr.; EISENHUT, BLAUERSTURMHUT, Ger. Early blue wolfsbane, or deadly aconite. _Hab._ Various parts of Europe; grows wild in England, flowering in June and July. The fresh and dried leaves (ACONITI FO''LIUM), Ph. L. & E. The root (ACONITI RA'DIX), Ph. L. & D. This is the species of aconite ordered in the pharmacop[oe]ias, and commonly used in medicine. When chewed it imparts a sensation of acrimony, followed by a pungent heat of the lips, gums, palate, and fauces, which is succeeded by a general tremor and chilliness. The juice applied to a wound or the unsound skin affects the whole nervous system. Even by remaining long in the hand, or on the bosom, it produces unpleasant symptoms. Fatal cases of poisoning, by eating the root in mistake for horseradish, have been common of late years. The two roots may be, however, easily distinguished from one another; when scraped aconite emits an earthy, and horseradish its well-known pungent odour. Moreover, the shape of the roots is very different. In the accompanying figure _a_ represents aconite root, and _b_ horseradish root.

The leaves should be gathered as soon as the flowers appear. The root should be taken up in autumn. When the whole plant is employed, it should be gathered as soon as the flowers begin to open. The strength (richness in aconitia) varies considerably with the time of the year. 1 oz. of the fresh root contains 1/4 to 3/4 gr. of aconitia; 1 lb. of the dried English root contains from 12 to 36 gr. (Herapath). The leaves possess the greatest activity just before flowering; the root, after it. The root is at all times fully six times as strong as the leaves or herb. The wild plant contains much more aconitia than that which is cultivated. The herb, and all its preparations, lose their efficacy if long kept. The powder, more particularly, cannot be relied on. Mr Holmes says it is difficult to find in a commercial sample of aconite root one root in a dozen, which upon fracture appears sound and in good condition.

_Properties, Antidotes, &c._ See ACONITE.

_Tests, &c._ See ACONITE.