PHARMACOLOGIA.

ABIETIS^[318] RESINA. L. E. D. (Pinus Abies, Resina concreta.) Resin of the Spruce Fir.

Olim, Thus—Frankincense.^[319]

Qualities. Form, tears or small brittle masses: Odour, very fragrant when burning. It has all the chemical properties of a Resin, and is used only for external purposes: see Pix Arida. Officinal Preparations. Empl: Aromatic: D. Empl: Galban: comp: L. Empl: Opii L. Empl: Thuris. D.

ABSINTHIUM. (Artemisia Absinthium) Common Wormwood.

Qualities. Odour, strong and peculiar. Taste, intensely bitter, slightly pungent, and very unpleasant, as its name^[320] implies. Chemical Composition. Extractive, a small portion of resin, and a green essential oil; in the first of which its bitterness resides, in the last, a narcotic principle; hence the watery extract is not possessed of the nauseous flavour of the plant but retains its bitterness almost entire; the narcotic principle is therefore dissipated by decoction, but its tonic and anthelmintic properties are not impaired by that process. Medical Uses. The whole plant is powerfully antiseptic; and its bitterness renders it stomachic. Infused in ale it forms the beverage known by the name of Purl. Its powers as a vermifuge has bestowed upon it the name of Wormwood. Dose, ℈j, ℈ij; and of the infusion, (made in the proportion of ℥j of the plant to oj of water,) f℥i-f℥iss. Incompatible Substances. Precipitates are produced in the decoction or infusion by Sulphate of Iron, Acetate of Lead, and some other metallic salts. Tartarized Antimony is not in the least affected by it. Off: Prep: Extract: Absinth: D.

246ACACIÆ GUMMI. L. (Acacia vera.) Mimosa. Nilotica. E. D. Gum Arabic.

Qualities. It is dry, semi-transparent, brittle and insipid; by exposure to the air it undergoes no other change than loss of colour. Specific Gravity, 1·515. Solubility. It is soluble in water in every proportion, forming a viscid solution, (mucilage). One part dissolved in water affords a fluid of the consistence of syrup; and in two parts, a medium well calculated for the union of dry powders. Gum is also soluble in pure alkalies and lime water, as well as in vegetable acids, especially vinegar, with which it forms a mucilage that may be used as a cement, like the watery solution, and with the additional advantage of not being susceptible of mouldiness.^[321] It is insoluble in alcohol, as well as in æther and oils. By strong sulphuric acid the gum is decomposed, and a considerable proportion of carbon deposited.^[322] For a farther history of its habitudes see Mucilago Acaciæ. Medicinal Uses. It is demulcent and nutritious; although it appears in certain states of the body to pass through the bowels without change. When triturated with gum-resins it assists their mechanical division, as in Form: 30. Officinal Preparations. Mucilago Acaciæ. L. E. D. Emulsio Mimosæ Niloticæ. E. Emulsio Arabica. D. Mist. Corn. ust. L. D. (O) Mist. Cretæ. L. D. (O) Mist. Moschi. L. (O) Confect. Amygdal. L. (O) Pulv. Cret. co. L. (O) Pulv. Tragacanth co. L. (B) Trochisci Carbonat. Calcis E. (O) Troch. Glycyrrh. Glab. E. (O) Troch. Glycyrrh. cum Opio E. (O) Troch. Gummos. E. (O). Adulterations. Gum Senegal is not unfrequently substituted for it, but this may be distinguished by its clammy and tenacious nature; whereas genuine gum arabic is dry and brittle; the fraud is of no consequence in a medical point of view. It is also occasionally mixed with the gum of plum and cherry trees; this fraud however, is to be easily detected, for such gum has peculiar properties by which it may be chemically distinguished; see Mucilago Tragacanth.

ACETICA. L.E.D. Preparations of Vinegar.

These preparations consist of vegetable principles dissolved in vinegar. Officinal Preparations. Acetum Aromaticum. E. Acidum Acetosum camphoratum. E. Medicated vinegars were formerly much extolled; the first London Dispensatory contained no fewer than ten, at present the number is reduced to two, viz. Acetum Colchici. L. Acetum Scillæ. L.E.D. which see.

ACETIS HYDRARGYRI. E. Acetas Hydrargyri. D. Acetate of Mercury.

Qualities. Form, small flaky crystals; Colour, silvery white; 247Taste, acrid. Chemical Composition. Acetic Acid, and Oxyd of Mercury. Solubility. It is soluble in hot, but very sparingly in cold water, and quite insoluble in Alcohol. Forms of Exhibition. It should be always given in pills,^[323] it is however seldom used. Dose, gr. j. As an external application, a solution of it, in the proportion of grs. j. to f℥i of rose water, has been commended as a cosmetic.

ACETOSÆ FOLIA. L.E. Rumex Acetosa.

Common Sorrel Leaves.

Qualities. Taste, grateful, austere and acidulous. Chemical Composition. All its qualities depend upon the presence of Super-oxalate of Potass. In France the plant is commonly cultivated for the use of the table.

ACETOSELLA. L. Oxalis Acetosella.

Wood Sorrel.

The qualities of this plant, like those of the preceding, depend upon Super-oxalate of Potass.

ACETUM. L. Vinegar.

Acidum Acetosum, E. Acetum Vini. D.

Qualities. Too well known to require description.^[324] Chymical Composition. Acetic acid largely diluted with water, vegetable gluten, mucilage, sugar, extractive matter, and frequently malic and tartaric acids, together with small proportions of sulphate of lime, sulphate of potass, and alcohol. Its composition however varies according to the fermented liquor from which it is obtained:^[325] e. g. wine yields a paler, purer, and stronger acid than fermented malt liquors or solutions of sugar, hence the superiority of that prepared in France and Italy. Vinegar is liable to spontaneous decomposition, or to become mouldy, and consequently for the purposes of pharmacy it should be distilled; as however the change depends upon the presence of gluten, it may if boiled be kept for a much longer time, and if powdered animal^[326] charcoal be previously 248added, it will become quite colourless like distilled vinegar, and that without being impaired in strength, whereas it always becomes much weaker by distillation. It is a curious circumstance that this is the only vegetable acid, except the Prussic, that rises in distillation in combination with water.

Adulterations. Sulphuric acid, as it does not produce any turbid appearance in vinegar, is generally the acid selected for sharpening it; but it must be remembered, that the maker is allowed by law, to mix one thousandth of its weight of Sulphuric acid^[327] with it; so that the muriate of baryta when added to such vinegar may be expected to produce 1⅕ grain of insoluble sulphate in every fluid-ounce; if a more considerable quantity of precipitate occurs, we may infer that an excessive proportion of sulphuric acid is present; although some allowance ought perhaps to be made for the presence of the sulphates of potass and lime, which are always contained in vinegar. Of this vinegar 1000 grains should saturate 148 grains of crystallized sub-carbonate of soda; a fluid-ounce of the same, 68–3/4 grains.^[328] For the purpose of making the vinegar appear stronger, acrid vegetables, as grains of Paradise, berries of Spurge Flax, Capsicum, Pellitory of Spain, &c. are sometimes infused in it, but by tasting it with attention, the pungency of such substances may be easily detected. For the other adulterations, see Acidum Aceticum.

The purest vinegar which I have ever examined is that manufactured from malt, by Mr. Mackintosh of Glasgow. The strongest malt vinegar is termed proof vinegar, and is called by the manufacturer No. 24; it is estimated to contain 4·73 per cent. of real acetic acid.^[329] Its strength in relation to the other forms of acetic acid, will be seen by referring to the Medicinal Dynameter, and to the table inserted under the article Acidum Aceticum Fortius. In the former Editions of this work it was stated, that a Vinegar had of late years appeared in the market produced from the distillation of wood, (Pyroligneous Acid.) This article has now come into very general use; and the manufacturers have at length succeeded in divesting it of that empyreumatic flavour which had so long rendered it objectionable. See Acidum Aceticum Fortius e Ligno destillatum.

ACETUM COLCHICI. L. Vinegar of Meadow Saffron.

Vinegar appears to be a solvent of the acrid and medicinal principle which resides in the bulb of this plant. Dose fʒss to fʒij. in any bland fluid. See Colchici Radix.

ACETUM SCILLÆ. L.E.D. Vinegar of Squill.

This preparation is an acetic solution of the acrid matter of the Squill, upon which its medicinal efficacy depends.^[330] Dose fʒss to fʒij. in cinnamon 249or mint water. See Scillæ Radix. Form. 107, 114. Alkalies and their carbonates are chemically incompatible with these Vinegars. This preparation, as well as the Oxymel, deposites when long kept a precipitate consisting of citrate of lime and tannin, but its medicinal efficacy is not on that account impaired.

ACIDUM ACETICUM DILUTUM. L. Acidum Acetosum Distillatum. E. Acetum Distillatum. D.

Common Distilled Vinegar.

Qualities. Odour, fainter and less agreeable than common vinegar (Acetum): Taste, less acid; Colour, none. Specific Gravity; Mr. Phillips states, that when prepared according to the directions of the Pharmacopœia, it varies from 1·007 to 1·009; and that 1000 grains of the latter require for their saturation, 145 grains of crystallized sub-carbonate of soda. I apprehend, however, that it will be found quite impossible to obtain a dilute acetic acid equal in strength or specific gravity, to that last mentioned, by the process of the London College;^[331] it may even be doubted whether it can be produced of the specific gravity 1·007. The general run of distilled vinegar as found in the shop of the druggist, varies from 1·005 to 1·006, and contains from 2·80 to 2·826 per cent. of real acid; when of the specific gravity of 1·009 it would contain about 4·73 per cent. Dr. Powell states (Translation of the Pharmacop: of London, 1815) that “one fluid-ounce ought to dissolve at least thirteen grains of white marble;” or, what is equivalent to it, 39·67 grains of crystallized Sub-carbonate of Soda; acid of this strength corresponds very nearly with six degrees of the Revenue Acetometer, the proportions being as follow, 100 grains of Pharmacopœia strength will saturate 8·68 grains of crystallized Sub-carbonate of Soda; 100 grains of acid of 6° of the Acetometer will saturate 8·70 grains of the salt. Chemical Composition. Acetic Acid more largely diluted than that in vinegar, with very minute portions of uncombined mucilage and extractive. Solvent Powers. It is capable of dissolving all those vegetable principles which are soluble in water, and in some cases, as in Squill, Colchicum, and in several Aromatics and Narcotics, its acid appears to extend its solvent powers; at the same time it often modifies or diminishes the medicinal virtues of the substances, as for instance those of Narcotics; this circumstance considerably limits its pharmaceutical application; when however it is employed, a portion of spirit should be always added, in order to counteract the spontaneous decomposition to which it is liable, and the acetic compound should be preserved in stopped bottles. Acetic acid does not dissolve true resins, but it has some action on gum resins. Medicinal Uses. It is refrigerant, and may be advantageously administered in hemorrhage; especially in cases where the acetate of lead has been given, since the solubility of this latter substance is increased by it. See Form. 57; externally, it may be a convenient adjunct to lotions containing lead. See Form. 147. In consequence of its chemical action upon osseous matter, it has been much employed 250at the Gloucester Infirmary to hasten exfoliation of carious bone. Adulterations. Sulphuric Acid may be detected by a precipitate being produced on the addition of acetate of baryta: this test however will not answer for its detection in common vinegar, for the reason stated under that article. See Acetum. Sulphurous Acid may be recognised by drawing a little of the vapour into the lungs. The presence of Nitric Acid may be discovered by saturating the suspected sample with pure potass, evaporating to dryness, and then treating the product with a highly concentrated alcohol, the acetate of potass will be thus dissolved, but as it exerts no action on the Nitrate it will be found in the residuum, and may be recognised by its deflagration, when thrown upon burning charcoal;^[332] Copper may be detected by the acid assuming a blue colour, when supersaturated with ammonia; and Lead, by a solution of sulphuretted hydrogen, producing a dark coloured precipitate. Tin however is the metal with which distilled vinegar is more usually contaminated, for no vegetable acid will act upon lead while any tin is present in the mixture, since the latter, being more oxidable than the former, is exclusively dissolved.

ACIDUM ACETICUM FORTIUS. L.

(Acidum Aceticum.)

(e Ligno Destillatum.)

vulgo, Pyroligneous Acid.

The acetic acid from wood has been very generally introduced to supersede the use of distilled vinegar for the purposes of Medicine and the Arts.^[333] It is at length found to be capable of such complete separation from all foreign matter as to afford a perfectly pure acetic acid, invariable in its acidifying power, and immutable in its chemical properties. In justice to the skill and industry of Messrs. Beaufoy and Co. of South Lambeth, I beg to state that I have examined various specimens of this acid from their manufactory, and that I find it free from those impurities which have 251hitherto constituted an insuperable objection to its introduction into the Materia Medica. The purified Pyroligneous acid, manufactured by this company, and sold under the name of “Improved Distilled Vinegar,” is perfectly free from any unpleasant taste, as well as colour and sediment; and it forms a limpid and colourless solution with ammonia. The common distilled vinegar of the shops varies essentially in strength as well as purity, differing in acidifying power from 30 to 40 per cent. in value: it is sometimes 7 degrees, and at others less than 5, by the Revenue Acetometer;^[334] and hence has arisen the difficulty of procuring an uniform article for medical application, a difficulty which the introduction of the pyroligneous acid seems calculated to overcome, as it may be procured from the manufacturers of any degree of concentration,^[335] from 6 degrees of the Acetometer, or 2·826 per cent. of real acetic acid to 130 degrees, or 61·49 per cent. of acid; and even of still higher strength if required; their common, or Proof acid is about equivalent in strength to that of the best Malt Vinegar, of which 100 grains will saturate 14½ grains of crystallized Sub-carbonate of Soda, and consequently contains 4·73 per cent. of real acid, and will require at least one half part of water to reduce it to the strength of the best common distilled vinegar. It is found that acetic acid of 45 per cent. real acid, or of 95° of acetometer strength, dissolves Camphor and the Essential Oils very readily.

The “Acidum Aceticum Fortius,” which is now introduced into the Materia Medica of the London College, is directed to have a specific gravity of 1·046.^[336] It is exactly six times the strength of Proof vinegar, or the strong Malt vinegar manufactured, but it requires to be diluted with nine times its weight of water to reduce it to the strength of the ordinary samples of distilled vinegar. Mr. Phillips states, that he has not met with acetic acid of greater specific gravity than 1·043,^[337] being five times the strength of vinegar of specific gravity 1·009.^[338] The strongest 252acid that can be procured is the Glacial acid, which exists in a crystallized state under 50° Fah. It contains 79 per cent. of real acid, and is consequently of the strength of 167·5 of the Acetometer. If this acid be kept perfectly still, it may be reduced several degrees below its crystallizing point in a fluid state, when the slightest agitation of the vessel instantly occasions it to solidify. It will greatly facilitate our inquiries into the strength of different samples of acetic acid to know, that the representative numbers of acetic acid and pure white marble coincide on the scale of equivalents; it therefore follows that the weight of marble dissolved by a hundred grains of any acetic acid, will at once represent the percentage of real acid in such a sample.

The Impure Pyroligneous acid, as it first comes over, contaminated with Tar, has, it is said, been very successfully employed as a lotion in Lepra, scrophulous ulcerations, chronic inflammation of the eyes, and edges of the eye-lids, and for promoting digestion of irritative ulcers, or those connected with carious bone. It has also been injected into sinuses to produce healthy discharge and adhesive inflammation.^[339] M. Monge discovered that this acid has the property of preventing the decomposition of animal substances; it is sufficient to plunge meat for a few moments in this acid, even slightly empyreumatic, to preserve it as long as you please. “Putrefaction,” it is said, “not only stops but retrogrades.” To the empyreumatic oil a part of this effect has been ascribed, and hence has been explained the agency of wood smoke in the preservation of tongues, hams, herrings, &c.

Acidum Acetosum Forte, E. Acidum Aceticum. D.

Radical Vinegar.

The process for this preparation has not retained its place in the London Pharmacopœia, as it is now universally superseded by the Acetic acid distilled from wood. Since however it possesses peculiar chemical habitudes, it claims some notice in this work. The concentrated acid obtained from the decomposition of acetic salts, by the action of sulphuric 253acid, is pungent, acrid, and volatile, and when heated with free access of air, it takes fire very readily. Its solvent powers are much greater than those of distilled vinegar; it is capable of dissolving camphor, resins, and essential oils^[340] copiously, but they are precipitated by dilution; it combines with alcohol, and forms a species of ether; with water it unites in any proportion, heat being evolved by the mixture. Gold, platinum, glass, and earthenware, can alone retain this acid without being corroded. It blisters the skin immediately.

I shall conclude this article by the introduction of a Table, which I have constructed with considerable care, for the use of the practical Chemist. The accuracy of the results may be depended upon, since it has been tested by several different modes of enquiry. The Medicinal Dynameter will give the equivalents in any other denomination that may be required.

A Table exhibiting the acetometer strengths, specific gravities, percentage of real acid, equivalent value, and saturating power, of the more important preparations of Acetic Acid.

ACIDS. Acetometer strength. Specific Gravity. Percentage of real Acid. Equivalents in Minims. Grains of Sub-carbonate of Soda saturated by 100 grains of acid.

Acetum Destillatum 5·9° 1·005 2·80 810 8·58

D° 6° 1·006 2·826 803 8·66

D° 7° 1·007 3·42 663 10·48

D° 10° 1·009 4·73 480 14·5

Acetum (Proof) 10° 1·014 4·73 480 14·5

Acid Acetic: Fort. 50° 1·043 23·67 96 72·5

Acid Acet: Fort. P. L. 60° 1·048 28·43 80 87

Acid: Acet: Fort. 75° 1·059 35·475 64 108·75

Acid: Acetic, D. Acid: Acetos: Fort. E. 145° 1·070 68·5 33·1 210·25

Acid: Acetic: Fort. (Glacial.) 167.5° 1·063 79 28·6 242·875

The reader will observe an anomaly with regard to the specific gravity of the acid of 145 of the acetometer, when compared with the glacial acid. The fact is, that by diluting this latter preparation with a small portion of water we augment its specific gravity, a circumstance peculiar to this acid.

254ACIDUM BENZOICUM. L.E.D.

Benzoic Acid. Vulgo, Flowers of Benzoin, or Benjamin.

Qualities. Form, small feathery crystals of a brilliant white colour, which are not brittle, but possess a kind of ductility and elasticity, and, on being rubbed in a mortar, assume the consistence of paste. Odour. As generally met with, it possesses a peculiar aromatic smell, but this depends upon the oily matter which adheres to it, for Mr. Guise informs us, that on dissolving the benzoic acid in as little alcohol as possible, filtering the solution, and precipitating by water, the acid will be obtained pure, and void of smell, the odorous oil remaining dissolved in the spirit. Taste, rather acrid and sour; Specific Gravity, ·667. It is not altered by exposure to air. Solubility. Four hundred parts of cold water dissolve but one, although the same quantity of boiling water dissolves twenty parts, nineteen of which separate on cooling; in alcohol it is soluble in a much greater proportion. Medicinal Uses. It is said to be stimulant and expectorant; in certain cases of tracheal irritation, a pill, composed of two grains of Benzoic acid, and three of Extract of Poppy, has been found serviceable. Officinal Preparations. Tinctura Camphoræ Composita, L.D. Tinct: Opii Ammoniat: E. Impurities. The crystals ought not to be discoloured; they should dissolve without residuum in alcohol, and when subjected to heat, ought to be entirely volatilized.

Although this acid is commonly procured from the resinous substance called Benzoin, yet it exists extensively in other vegetable, and in some animal substances. In the Tonca bean (Dipterix odorata) it is frequently to be seen beautifully crystallized on its surface. It exists also in vanello; cinnamon; cloves; ambergris; in the urine of children, and sometimes in that of adults, and always in that of quadrupeds living on grass and hay.

255ACIDUM CITRICUM. (Crystalli) Citric Acid.

Concrete Acid of Lemons.

Qualities. Form, crystals which are right rhombic prisms, white, semi-transparent, and persistent. Taste, extremely acid, almost caustic. Solubility, f℥j of cold water dissolves ʒx, but of boiling, ℥ij. ʒx of the crystals dissolved in a pint of water, are about equivalent to one pint of lemon juice, the solution however if kept is liable to spontaneous decomposition. The following table of equivalents may be found of practical use; the author is aware that they do not exactly agree with the proportions of Dr. Haygarth, but they are the results of careful and repeated experiments, and as such they are submitted with confidence.

EQUIVALENT PROPORTIONS OF CONCRETE CITRIC ACID AND LEMON JUICE, NECESSARY FOR THE NEUTRALIZATION OF ALKALINE SALTS.

Citric Acid. Lemon Juice. A Scruple of Alkalies.

grs. x. fʒiij Carbonate of Potass.

grs. xv. fʒiiij Sub-Carbonate of Potass.

grs. xxv. fʒvij Sub-Carbonate of Ammonia.

These alkaline citrates are decomposed by the oxalic, tartaric, and the stronger mineral acids, and by the solutions of lime and barytes. Form. 107, 123, 137, 168.

Citric acid decomposes the following salts, viz. The Alkaline, Earthy, and Metallic Carbonates; the Alkaline and Metallic Acetates; the Sulphurets of Earths and Alkalies, and Alkaline Soaps. It is also incompatible with Tartrate of Potass, which it converts into citrate and super-tartrate of potass. It curdles the milk of most animals, but it does not produce that effect on human milk, whether applied hot or cold. Adulterations. Tartaric Acid, with which it is sometimes mixed, may be detected by adding to the solution an excess of Potass, which will instantly form with it an insoluble super-tartrate, and precipitate in granular crystals, or, if a little of the suspected acid be saturated with potass, and then boiled with a dilute solution of muriate of Platinum, if tartaric acid be present, a black protoxide of Platinum will be precipitated. If we add the tartrate of potass for this purpose, we may be deceived, for the citric acid, by neutralizing a portion of its base, will convert the remainder into super-tartrate. See Potassæ Tartras. Sulphuric Acid is known by the acetate of lead producing a precipitate, insoluble in nitric acid. Muriatic Acid may be discovered in the same manner, substituting only an acidulous solution of nitrate of silver for the acetate of lead. The presence of Oxalic Acid 256may be inferred, if the solution, when added to that of sulphate of lime, produce a precipitate. Malic acid has the power of precipitating silver, mercury, and lead, from their solutions in nitric acid, but no doubt or difficulty can arise from this circumstance, for the fact of its forming a soluble salt with lime will prevent every chance of accidental intrusion, and its price at once secures us against its fraudulent introduction; it might moreover be easily detected by throwing the suspected precipitate upon burning coals, when it would be decomposed. Where the presence of lime is suspected, it may be known by dissolving some of the crystals in water, saturating the solution with ammonia, and then treating it with the oxalate of that alkali, which, if lime be present, will immediately separate it in a palpable form. The juices of many other fruits besides the lemon and lime, will furnish the citric acid in abundance, and may be obtained from them by a similar process; e. g. Vaccinium oxycoccus, the Cranberry; Prunus Padus, the Bird’s Cherry; Dulcamara Solanum, the berry of the Nightshade; Cynosbatus, vel Rosa Canina, the hep or fruit of the Wild Briar. There are many plants whose juices contain combinations of the Citric and Malic acids in considerable abundance, such as Fragaria Vesca, the Wood Strawberry, and the common Raspberry; Ribes Rubrum the Red Gooseberry; Vaccinium Myrtillus, the Bilberry; Cratægus Aria, the Hawthorn; Prunus Cerasus, the Black Cherry, &c. This fact is interesting, since the juices of such fruits have been long known to possess the property of dissolving the tartareous incrustations on the teeth.

ACIDUM HYDRO-CYANICUM.

Hydro-cyanic Acid. Prussic Acid.

This peculiar acid exists in a great variety of native combinations in the vegetable kingdom,^[341] and imparts to them certain properties which have been long known, and esteemed in medicine. It is, however, only lately, that it has been administered in its simple but diluted form. As few practitioners 257will choose to prepare the acid, it seems unnecessary in the present work to dwell upon the merits of the different processes which have been proposed for its preparation; for a full account of them, as well as for other details of importance, the practitioner is advised to consult a work by Dr. Granville, entitled “An Historical and Practical Treatise on the use of Prussic Acid. Second Edition. London, 1820.”

Qualities. A colourless transparent liquid, although it occasionally exhibits a yellow tinge; Odour like that of bitter almonds; Taste bitterish and peculiar: these properties however are soon lost by exposure to air and light, and the acid undergoes spontaneous decomposition. Chemical Composition. The true nature of Prussic acid was not ascertained until 1815, when Gay Lussac presented to the Royal Institute of France, a memoir which at once developed its real chemical constitution; and it is now admitted to consist of a peculiar gaseous and highly inflammable compound of carbon and nitrogen, to which the name Cyanogene has been assigned, and of hydrogen; the latter body acting as the acidifying principle, whence the term Hydro-cyanic acid is well contrived to express its composition. The medicinal, or diluted acid, however, contains but a small proportion of this concentrated compound; according to M. Majendie, one part of the acid of Gay Lussac and eight parts and a half of water, by weight, or one part of acid with six times its volume of water, constitute the preparation which should be used in medicine; and which, to avoid the possibility of mistake, ought always to be prescribed as the Acidum Hydro-cyanicum dilutum, and is, in fact, the Prussic acid of Scheele. Dr. Ure, who has lately taken considerable pains upon this subject, has constructed a table exhibiting the relations between the specific gravities, and quantities of real acid, in preparations of different strength; from these experiments it would appear that an acid of specific gravity 0·996 or 0·997 is such as is usually prescribed in medicine.^[342] Medical 258Uses. In a sufficient dose, hydro-cyanic acid instantly destroys life by extinguishing the nervous energy of the body;^[343] but it has at the same time been observed that animals submitted to its action would often continue to breathe for several hours freely, and to circulate their blood, although no trace of sensibility or muscular contractility could be found after its application. This remarkable property of extinguishing the general sensibility, without any ostensible injury to respiration and circulation, naturally led to a belief that the hydro-cyanic acid, or prussic acid, might be advantageously used in cases of excessive sensibility and irritation, particularly when these two morbid states are likely to affect either the respiratory organs or the circulation generally. This kind of analogical reasoning, it is said, induced Professor Brera, ten years ago, to administer it in cases of high pulmonary and other inflammations, in doses of four drops twice a day; when, as we are told, the violence of the disease was quickly subdued. The remedy, however, does not appear to have excited much attention, until after the first essay of Dr. Majendie, who deserves whatever credit may belong to its introduction. Seven years of trial have elapsed, and the general sense of the medical profession with respect to its utility may now be collected. As a palliative in certain spasmodic coughs, there is reason for supposing that it may sometimes be useful, but in that species of pulmonary irritation for which it was at first so greatly extolled, I will venture to assert that it is far inferior in efficacy to well directed doses of Conium. But there is another class of diseases in which its exhibition is said to prove useful, in dyspeptic affections attended with heartburn; where it is supposed to be capable of reducing the morbid irritability of the stomach, and thereby of enabling the juices of that organ to be more slowly secreted and of a more healthy character. Dr. Elliotson has published the result of his treatment of stomach complaints with this medicinal agent, and would appear to appropriate to himself the merit of originating the practice, a claim which Mr. Thomson, in the third edition of his Dispensatory, refuses to concede.^[344] As a local remedy, prussic acid has also received no small share of commendation, and it has been said that it is the only application that can be depended upon for allaying the cutaneous irritation so frequently attendant upon certain impetiginous affections. It must, however, be confessed that this medicine is rapidly declining in popularity.^[345] Any prejudice raised against it, upon the ground of its poisonous activity in large doses, is too absurd to be believed; the knife and the caustic are unquestionably powerful, and may therefore become dangerous instruments; but who ever blames the surgeon for employing a sharp knife or an active caustic, seeing that both are to be directed by his eye, and guided by his hand? Forms of Exhibition. It may be conveniently administered in any liquid vehicle, as distilled water, camphor mixture, or in some vegetable infusion. See Supplementary Formulæ, 1, 2, 3. A question has lately arisen whether the effects of the prussic acid might not be more conveniently ensured by the administration of some vegetable^[346] in which it exists as a 259native ingredient; a company of associated Physicians, Surgeons, and Naturalists at Florence, have accordingly expressed their joint opinion, that the essential oil of the Prunus Lauro Cerasus is to be preferred in medical practice to all other preparations which contain the hydro-cyanic acid; for, say they, unlike the distilled water of the plant, and pure prussic acid, it contains the same proportion of active matter, and of the same power, whether recently prepared or not; whether made in one place or another; or whether it has been exposed or not to the air, light, or heat. They are also of opinion that olive oil forms the best vehicle for its exhibition in the proportion of one ounce to twelve drops of the essential oil. Other practitioners again prefer Laurel Water, made by distilling two drachms of the fresh leaves chopped, with four ounces of water, recommitting the distilled water twice afterwards on the same quantity of fresh leaves, and making ultimately four ounces of the menstruum, of which from ♏︎xxx to fʒj every six hours may be given until a sedative effect is produced. See Oleum Amygdalæ Amaræ. Incompatible Substances. Hydro-cyanic acid is decomposed by most of the oxydes usually employed in medicine, particularly by those of Mercury and Antimony. The alkalies do not appear to diminish its efficacy. Nitrate of Silver, and the salts of iron occasion precipitates; nor ought the sulphurets, the mineral acids, or chlorine to enter with it into prescriptions. Dose. Of the medicinal, or diluted hydro-cyanic acid, ♏︎ij,–viij. There is however considerable difficulty with regard to the strength of the dilute acid employed in medicine, since the density is a criterion of greater nicety than can be conveniently used by the majority of practitioners; in fact, as Dr. Ure has observed, the liquid at 0·996, contains about double the quantity of real acid, which it does at 0·998. Dr. Ure has accordingly proposed another test of the strength of this powerful and dangerous medicine, which is not only easier in use, but more delicate in its indications;^[347] it is as follows. To 100 grains, or any other convenient quantity of the prussic acid, contained in a small phial, add in succession, small quantities of the peroxide of mercury, (the common red precipitate of the shops) in fine powder, till it ceases to be dissolved on agitation. The weight of the red precipitate taken up, being divided by four, gives a quotient representing the quantity of real prussic acid present. By weighing out before hand, on a piece of paper, or a watch glass, forty or fifty grains of the peroxide, the residual weight of it shews at once the quantity expended. The operation may always be completed in five minutes, for the red precipitate dissolves as rapidly in the dilute prussic acid, with the aid of slight agitation, as sugar dissolves in water. Adulterations. If, says Dr. Ure, the presence of muriatic acid be 260suspected, then the specific gravity of the liquid compared with the gravity of the peroxide dissolved, will shew how far the suspicion is well founded; thus if 100 grains of acid, specific gravity 0·996, dissolve more than 12 grains of the red precipitate, we may be sure that the liquid has been contaminated with muriatic acid. Nitrate of Silver, in common cases, so valuable a reagent for muriatic acid, is unfortunately of little use here, for it gives with prussic acid, a flocculent white precipitate, soluble in water of ammonia, and insoluble in nitric acid, which may easily be mistaken by common observers, for the chloride of that metal. But the difference in the volatility of prussiate and muriate of ammonia may be had recourse to with advantage; the former exhaling at a very gentle heat, the latter requiring a subliming temperature of about 300° Fah. After adding ammonia in slight excess to the prussic acid, if we evaporate to dryness at a heat of 212°, we may infer from the residuary sal ammoniac, the quantity of muriatic acid present.

Antidotes. To counteract the poisonous effect of prussic acid, Orfila recommends, after full vomiting has been excited, the exhibition of three or four spoonsful of oil of turpentine, in the infusion of coffee, at intervals of half an hour. M. Virey conceives that sulphate of iron in solution is the best antidote, he having observed that the salt restored a cow that was nearly killed by the essential oil of bitter almonds. When an overdose has been taken, hot brandy and water, and the ammoniated tincture of iron are recommended by Mr. Thomson; on the former I should rely with much greater confidence than upon the latter antidote, or, in other words, it is from vital agents, counteracting its sedative influence, rather than from chemical substances, changing its composition, that we can expect any benefit upon such an occasion. For the chemical processes by which the presence of this acid may be ascertained, the reader may consult my work on Medical Jurisprudence, vol. 2, p. 408.

ACIDUM MURIATICUM. L.E.D.

Muriatic Acid.

Qualities. Form, a liquid of the specific gravity 1·16, a fluid-ounce of which weighs about 527 grains, and according to Dr. Powell ought, when diluted, to dissolve 220 grains of limestone. Odour, strong and pungent; if exposed to the air it emits white fumes. Taste, intensely sour and caustic; it is however the weakest of the three mineral acids; and no remarkable elevation of temperature is produced by dilution. Chemical Composition. The liquid acid is a solution of muriatic acid gas in water; when of the specific gravity 1·16, according to Davy, it contains 32·32 per cent of the gas, which recent experiments have shewn to be a compound of Chlorine (Oxy-muriatic acid) and hydrogen in equal volumes. It has therefore received a name expressive of its composition, and is called Hydro-chloric^[348] acid. We accordingly find that the former element is disengaged from muriatic acid by adding any substance capable of uniting 261with its hydrogen. For the purpose of obtaining Chlorine, we may take three parts of common salt, one of black oxide of manganese, and rather less than three of strong sulphuric acid.^[349] Accounts have been received from Spain, that in the midst of the dreadful contagion which reigned in that country, the inhabitants always escaped in those houses where fumigations of chlorine had been used. In our own country, the Penitentiary has lately undergone fumigation by this gas, under the superintendance of Mr. Faraday.^[350] Muriatic acid gas has also been strongly recommended for the same purpose; it may be easily evolved by pouring sulphuric acid on common salt. If nitric and muriatic acids be mixed, a mutual decomposition takes place, of which water, chlorine, and nitrous acid are the results; this constitutes “nitro-muriatic acid,” the Aqua regia of the older chemists. A bath acidulated with an acid of this kind has been recommended by Dr. Scott, as a powerful remedy for diseases of the liver in particular, and as a substitute for mercury in general. On the possible influence of this bath, I would beg to make one observation,—that the extensive application of a dilute acid to the surface of the body, is, under certain circumstances, capable of affecting the bowels. I have witnessed such an effect from sponging with vinegar and water. In this way the acidulated bath may occasionally produce benefit, but it is extremely difficult to conceive how it can be indebted for its utility to any other mode of operation. (See Journal of Science and the Arts, No. 2.) Forms of Exhibition. Muriatic acid should be administered in some bland fluid, as barley water, gruel, &c. (Formula 145.) I have uniformly exhibited it with success in the most malignant cases of typhus and scarlatina, during several years extensive practice in the Westminster Hospital. See page 157. We should be careful not to apportion its dose in a leaden or pewter spoon. The antiseptic properties of this acid have been long known; Sir Wm. Fordyce relates that a “dry-salter” acquired a large fortune from possessing a secret that had enabled him to send out provisions to India in a better state of preservation than any others of the trade; his secret consisted in adding a small quantity of muriatic acid to the contents of each cask. After a copious evacuation of the bowels, it is in my experience the most efficacious remedy for preventing the generation of worms; for which purpose the infusion of quassia, stronger than that of the Pharmacopœia, is the best vehicle. Dose, ♏︎v-xx, frequently repeated. It may be here observed that where the permanent influence of an acid is required, a mineral one should be always preferred, as such bodies appear to be beyond the control of the digestive process,^[351] and are incapable of being decomposed by it; see Form. 158, whereas on the contrary it seems probable that the organs of assimilation have command over those of a vegetable nature, and generally decompose 262them. Dr. Marcet has very judiciously noticed this fact in his luminous work on the treatment of calculi, and I have ventured to offer some farther observations upon this subject, which may be of practical value, under the consideration of Lithonthryptics, page 123. Adulterations. Sulphuric acid is detected by diluting the acid with six parts of distilled water, and adding a few drops of the muriate of baryta, which occasions a white precipitate if any be present. Iron, by saturating a diluted portion with pure carbonate of soda, and adding prussiate of potass, which will indicate its presence by a blue precipitate; or by a solution of ammonia, which, when added slightly in excess, throws down the peroxide of iron of a reddish yellow colour. Copper, by the production of a blue colour when supersaturated with ammonia. The yellow tinge of the acid usually met with in commerce, may depend either upon the presence of iron, vegetable extractive, or a small portion of chlorine. This latter body may be recognised by the odour, or by its power of dissolving gold leaf.

ACIDUM NITRICUM. L.E.D. Nitric Acid.

Aqua Fortis.

Qualities. A limpid liquid of the specific gravity 1·500, a fluid-ounce of which is equal to about 11 drachms, 1 scruple by weight, and ought to decompose of pure limestone an ounce; it emits white fumes of a suffocating odour. Taste, extremely acid; it is highly corrosive, and tinges the skin indelibly yellow; an effect which is considerably heightened by the subsequent application of an alkali, so that these agents afford the means of detecting minute portions of animal matter, and were ingeniously employed for such an object by Mr. Hatchett. Chemical Composition. When of the specific gravity 1·500, it contains 74·895 per cent. of dry acid; (whose ultimate elements are one portion of nitrogen and five of oxygen) the compliment 25·105 parts is water. It is decomposed with violent action by all combustibles, and when mixed with volatile oils, it causes their inflammation. It boils at 210°, and when its specific gravity is below 1·4, it is strengthened, when stronger than 1·45 it is weakened by ebullition. Uses. It is principally employed as a pharmaceutical agent; viz. for the preparation of Argenti Nitras; Liquor Ferri Alkalini; Hydrargyri Nitri-co-oxydum; Spiritus Etheris Nitrici; and Unguentum Hydrargyri Nitratis. As an escharotic it has been frequently employed for the destruction of tumours, and is certainly of value where an immediate destruction of diseased parts is required. The method of using the strong nitric acid in such cases is to smear all the sound parts in the immediate vicinity of the ulcer with Ung: Resin: Nig: and then to apply pledgets of lint firmly upon the ulcer for a few seconds, by which the whole surface will be deadened, and a deep slough remain, underneath which healthy suppuration and granulations will ensue.^[352] Adulterations. Sulphuric acid may be 263detected by a precipitate being produced on the addition of nitrate of baryta; in the application however of this test, Mr. Hume has shewn that unless this as well as the nitric acid be diluted, a precipitate will occur, although sulphuric acid should not be present; a circumstance which depends upon the barytic salt yielding its water of solution to the acid under examination, and becoming insoluble. Muriatic acid is discovered by nitrate of silver, affording a precipitate at first white, but becoming coloured by exposure to light; the nitric acid ought to be perfectly colourless, but to preserve it in such a state it must be closely stopped, and kept in a dark place, or it will soon be converted into nitrous acid.

ACIDUM NITRICUM DILUTUM. L.

Acidum Nitrosum Dilutum. E.D.

Dilute Nitric Acid.

It is much to be regretted that the proportion of water directed for the dilution of the acid, varies considerably in the different pharmacopœias; that prepared according to the Edinburgh and Dublin formulæ, being in strength to that of the present Pharmacopœia of London, as 4 to 1: specific gravity, 1·080; each fluid-drachm contains nearly 8½ grains of the concentrated acid, and saturates 18 grains of crystallized sub-carbonate of soda. Dose ♏︎x to xl. The acid is a very powerful anti-phlogistic remedy; it has been much extolled in diseases of the liver, and in syphilis. Mr. Pearson however observes that we ought not to rely upon it in any form of lues venerea, although it may be often serviceable in restraining the progress of the disease when an impaired constitution or other circumstances render the exhibition of mercury improper; when sufficiently dilute, it forms an excellent lotion for old indolent ulcers. It proves also expectorant, see Form. 139, 140; and it is occasionally used with success for the purpose of counteracting the consecutive effects of opium. See Form. 16.

ACIDUM NITROSUM. E.D. Nitrous Acid.

Qualities. A liquid emitting fumes of a flame-red colour, and of a very pungent and remarkable odour. The acid is either blue, green, straw-coloured, clear orange yellow, according to the proportion of nitrous acid gas^[353] with which it is charged. Chemical Composition. This acid is improperly denominated Nitrous, for it is nitric acid, holding nitrous acid gas loosely combined; by dilution this last constituent is disengaged, and the acid, after passing through a succession of different colours, becomes pure nitric acid; the application of a gentle heat effects the same changes.

ACIDUM SULPHURICUM. L.E.D. Sulphuric Acid.

Oil of Vitriol, Vitriolic Acid.

Qualities. Form, a thick liquid of an oily consistence, specific gravity 1·85; a fluid-ounce weighs a fraction of a grain more than fourteen drachms. Colour, none, but it acquires a brown tinge from the smallest 264portion of carbonaceous matter; mere exposure to the air is sufficient for this purpose, in consequence of the acid disorganizing and carbonating the vegetable and animal matter suspended in the atmosphere; it is therefore evident that bottles in which it is preserved ought not to have stoppers of cork, but those of glass. Chemical Composition. Like the other mineral acids, it has never been obtained in an insulated state without water; according to Davy, the composition of the strongest acid may be thus expressed: sulphur 30, oxygen 45, water 17. It has a very powerful affinity for water, and produces when mixed with it a very considerable heat; exposed to the atmosphere it imbibes at least seven times its own weight of water, and so rapidly as to double its weight in a month; when of the specific gravity 1·85, it rises in vapour at about 550°, and distils unaltered, whereas weaker acids lose water by being boiled, and are brought to that degree of concentration; when diluted with 12 or 13 per cent. of water, an acid results of the specific gravity 1·780, and in this state of dilution it boils at 435°, and freezes sooner than water; a knowledge of this curious fact suggests to the prudent chemist an important precaution; Mr. Parkes, in his Chemical Essays, vol. ii. relates the occurrence of a terrible accident which happened in consequence of this circumstance not having been attended to.—“Carboy after carboy burst by the expansion of the acid in the act of freezing, and had not the packed carboys that remained been immediately immersed in tepid water, not a single one would have escaped the general wreck.”

Adulterations. The ordinary acid of the shops contains in general 3 or 4 per cent. of saline matter, which consists of about two-thirds of sulphate of potass, and one-third of sulphate of lead. Dr. Ure observes, that even more is occasionally found, in consequence of the employment of nitre to remove the brown colour given to the acid by carbonaceous matter; the amount of adulteration, he observes, may be readily determined by evaporating a definite weight of the acid in a small capsule of platinum; these impurities however in a medical point of view are immaterial, since they are at once separated by dilution, but in a commercial sense they deserve attention, as their presence considerably increases the specific gravity of the acid. Dr. Ure is of opinion that genuine commercial acid should never exceed 1·8485, and that any density beyond this is the effect of saline combination. Journal of Science and the Arts, No. 7.

ACIDUM SULPHURICUM DILUTUM. L.E.D.

Dilute Sulphuric Acid.

By the dilution of this acid two objects are accomplished,—it is purified, and its dose is more easily apportioned; but it is a circumstance of regret that the strength of this preparation should so materially vary in the different Pharmacopœias.

After the acid is diluted, the sediment ought to be carefully removed, and the water employed for the purpose should be distilled, for although it be in its purest natural state, it will nevertheless contain impregnations capable of affecting the acid. Uses. In addition to the antiseptic and refrigerant virtues which it possesses in common with the other mineral acids, it has astringent properties that render it a most valuable medicine, 265especially in weakness and relaxation of the digestive organs, in colliquative sweats, in internal hæmorrhagy; in Epistaxis and Hemopthysis it was Sydenham’s favourite remedy; on the same account, when sufficiently dilute, it has been successfully used as a collyrium in the atonic stages of ophthalmia, and as an injection in protracted gonorrhæa. Dose, ♏︎x to xl, the quantity of strong sulphuric acid in any given quantity of the dilute may be found by the Dynameter. To prevent it from injuring the enamel of the teeth it may be sucked through a quill, and the mouth should be carefully washed after each dose. The Infusum Rosæ furnishes an elegant vehicle for its administration. See Form. 40. Officinal Preparations. Acidum Sulphuricum Aromaticum.^[354] E. Infusum Rosæ. L.

ACIDUM TARTARICUM. L.

Tartaric Acid.

Qualities. Form, Crystals of considerable size, whose primary form is an oblique rhombic prism; they do not deliquesce when exposed to the air, but melt at a heat a little exceeding 212°. Taste, very acid and agreeable. Solubility. Water at 60° dissolves about one-fifth of its weight, and when boiling, a much greater proportion. The solution, which, if saturated, has the specific gravity 1·230, acquires, when diluted, like that of most vegetable acids, a mouldy pellicle by keeping. The saturating power of crystallized tartaric acid is almost exactly equal to that of crystallized citric acid, the atomic weight of the former being 76, and that of the latter 75. Chemical Composition. When uncombined with water, as it exists in tartrate of potass, it is composed of 5 atoms of oxygen, 3 atoms of hydrogen, and 4 atoms of carbon. The crystals consist of 1 atom of acid and 1 of water. Incompatible Substances. Alkalies, Earths, and their carbonates; the salts of lime and lead. The solutions of the salts of potass are converted by it into bi-tartrate, or super-tartrate. Medicinal Uses. It is introduced into the Pharmacopœia as a cheap and efficient substitute for the citric acid. It is also used in the preparation of Sodaic powders, Seidlitz powders, &c. Adulterations. When carelessly prepared it will contain sulphuric acid, to detect which, let a portion be dissolved in distilled water, and a solution of acetate of lead be added. A precipitate will appear which, if the acid be pure, will be entirely redissolved by a few drops of acetic acid, or pure nitric acid. If any portion remain undissolved, sulphuric acid is the cause. Muriate of Baryta also, when sulphuric acid is present, but not otherwise, gives a precipitate insoluble by an excess of muriatic acid.

266ACONITI FOLIA. L.E.D. (Aconitum Napellus.^[355]) Aconite.

Woolfsbane, Monkshood.

Qualities. Taste, moderately bitter, and acrid, leaving in the mouth a painful sensation of heat and roughness, followed by numbness in the gums and lips which continues for two or three hours. Odour, faint and narcotic; their peculiar properties are considerably deteriorated by drying. Chemical Composition. M. Brandes has ascertained that the narcotic principle of this plant is a peculiar alkali, to which he has given the name Aconita.^[356] Solubility, water and alcohol only imperfectly extract their virtues. Medicinal Uses. It is narcotic, and occasions, in over-doses, nausea, vomiting, vertigo, hyper-catharsis, cold sweats, convulsions, and death; effects which entirely depend upon its action on the brain. It was first administered in 1702, by Stöerk, of Vienna, in chronic rheumatism, gout, schirrus, and paralysis; more lately it has been employed in scrofula, cancer, and intermittents, and it is said with much effect. On account of the variable strength of the leaves they can hardly be given with safety and effect; the extract (which see,) presents the more eligible form of exhibition. The leaves are, however, sometimes given in the form of powder, generally combined with some mercurial alterative, or with antimonials, camphor, and other diaphoretics. Dose gr. i-x. Officinal Prep: Extractum Aconiti. L.E.

ADEPS PRÆPARATA. L. Adeps Sui Scrofæ, vulgo Axungia Porcina. E. Adeps Suillus Præparatus. D.

Prepared Hog’s Lard. Fat. Axunge.^[357]

Qualities. Consistence, soft or nearly semifluid. Odour and Taste, none; at 97° it melts. Chemical Composition. It consists of two distinct bodies which appear to exist together in a state of mechanical mixture, viz. Stearin, (from στεαρ tallow) which is white, brittle, and in appearance somewhat resembling wax; and Elain (from ελαὶον, oil) very similar to vegetable oil in appearance, and is liquid at 59°. According to the experiments of Braconnot, the proportion of Elain is to that of Stearin, in hog’s lard, as 62:38. Solubility. It is insoluble in water and alcohol; with the alkalies it unites and forms soaps. Incompatible Substances. Extracts, Spirituous Preparations, Tinctures, and Infusions, are incapable of uniting perfectly with lard, without some intermedium; the following substances on the contrary are capable of contracting with it a most intimate union. 1. All dry powders, whether of a vegetable or mineral nature. 2. Fixed and Volatile Oils. 3. Balsams. 4. Camphor. 5. Soaps. It is principally employed in the formation of ointments, plasters, and liniments.

267ÆRUGO. L. D. (Sub-acetas Cupri Impura.) Sub-acetis Cupri. E.

Verdigris.

Qualities. Form, a dry mass composed of minute crystals, not deliquescent; Colour, bluish green. Chemical Composition. Several constituents enter into its composition, viz. Acetate and sub-acetate of copper, carbonate of copper, and copper partly metallic and partly oxidized; it contains also the stalks of grapes and other extraneous substances. Solubility. Boiling water dissolves it in part, and produces in it a chemical change, by transforming one portion of the sub-acetate into the soluble acetate, and another into an oxyd of copper, which is precipitated; with cold water this substance demeans itself differently, the acetate is dissolved by it, whilst that portion which is in the state of sub-salt remains suspended in the form of a fine green powder. Vinegar converts all the Ærugo into a soluble acetate, this liquid therefore ought never to be employed for favouring vomiting in cases where an overdose has been swallowed, for the reasons stated in the first part of this work, p. 136. Sulphuric acid poured on powdered verdigris decomposes it with effervescence, and vapours of acetic acid are disengaged. It appears from the experiments and observations of Duval and Orfila, that sugar exercises a chemical action on it, by which its solubility is diminished, and that on this account it acts as a specific against its poisonous effects. Uses. It is so uncertain and violent in its operation that it is rarely employed, except externally,^[358] when it acts as a powerful detergent, and mild escharotic; and in the form of ointment, is a valuable application for many cutaneous affections, especially the aggravated kinds of Tetter. Officinal Preparations. Ærugo Præparata, D. Linimentum Æruginis. L. D. Adulterations. There is a spurious article sold under the name of English Verdigris, which consists of sulphate of copper, triturated with acetate of lead; and to make the fraud still more complete, the soft mass is mixed with the stalks of Raisins.

ÆTHER SULPHURICUS RECTIFICATUS. L.

Rectified Sulphuric Æther.

Qualities. A colourless liquid of specific gravity 739°. Odour, pungent and fragrant; it is highly volatile, and when perfectly free from alcohol it boils at 98°; it is extremely inflammable, a circumstance which should be remembered when it is poured from one vessel to another by candle light. Chemical Composition. When pure it consists of oxygen, hydrogen, and carbon; the rectified æther however still contains some water and alcohol, for Lovitz obtained an æther of 632. Solubility. One part requires for its solution ten of water; with alcohol and ammonia it unites in every proportion. Solvent Powers. It is one of 268the most powerful solvents known in vegetable chemistry, as it dissolves balsams, resins, gum-resins, wax, camphor, extractive, &c.; it takes up about a twentieth of its weight of sulphur, but it exerts no solvent power upon the fixed alkalies. Forms of Exhibition. In any liquid vehicle, if in decoctions or infusions, they should be previously cooled. See Formulæ 20, 22, 23. Medical Uses. It is highly valuable as a diffusible stimulant, narcotic, and antispasmodic. Dose, fʒss to fʒij, which, in order to produce the full effect of the remedy, must be repeated at short intervals. Æther, independent of such virtues, has another valuable property consequent upon its rapid evaporation, that of producing cold and dryness; it is therefore, when externally applied and allowed to evaporate, a most powerful refrigerant, and has proved valuable in scalds or burns, in facilitating the reduction of strangulated hernia, and in diminishing excessive circulation in the brain; if however it be so confined, that its rapid evaporation is prevented, a very opposite effect is produced, and it proves stimulant, rubefacient, and even vesicatory. With regard to the other property incidental to it, that of producing dryness, I am not aware that it has hitherto been applied to any pharmaceutical purpose; the fact may be satisfactorily shewn by a very simple experiment,—by rincing a phial with æther, to the interior of which drops of water obstinately adhere, when by exposing it to a current of air, it will be completely dry in a few minutes. It may be noticed in this place that a mixture of sulphuric and muriatic æthers evaporates instantaneously, and produces a degree of cold considerably below 0 of Fahrenheit. Officinal Preparations. Spiritus Æther: Sulph: L. Spir: Æth: Sulph: comp: L. Spir: Æth: Aromat: L. Adulterations and Impurities. Its specific gravity affords the best indication of its purity; Sulphuric Acid may be detected by a precipitation on the addition of a solution of baryta, and by its reddening the colour of litmus; Alcohol, by its forming with phosphorus a milky instead of a limpid solution. M. Gay Lussac has observed that when kept for a considerable time without disturbance, it undergoes spontaneous decomposition, and that acetic acid, perhaps some alcohol, and a particular oil, are produced from it.

ALCOHOL.^[359] L.D. Alcohol. Ardent Spirit.

Qualities. A transparent, and colourless liquid of the specific gravity ·815; it has not hitherto been rendered solid by any diminution of temperature; it boils at 176°, and if water be added, its boiling point is proportionably raised; hence, says Dr. Henry, the temperature at which it boils is not a bad test of its strength; it is combustible, and burns with a blue flame, leaving no residue. Chemical Composition. Alcohol, in a state of complete purity, consists of carbon, hydrogen, and oxygen, in proportions not hitherto determined with accuracy; this preparation however contains 7 per cent. of water; Lovitz and Saussure succeeded in obtaining it at a specific gravity of ·791, which may be considered as nearly pure. Alcohol unites chemically with water; and caloric is evolved during this union; the quantity of alcohol and water in mixtures of different specific gravities, may be learned from Mr. Gilpin’s tables, 269Philosophical Transactions, 1794, or Nicholson’s Journal, 4to. vol. 1. The Edinburgh Pharmacopœia has no process for the preparation of alcohol, but it most incorrectly assigns the title to that which is the “Rectified Spirit” of the other Colleges. Solvent Powers. Alcohol dissolves soap; vegetable extract; sugar; oxalic, camphoric, tartaric, gallic, and benzoic acids; volatile oils; resins, and balsams; it combines also with sulphur, and the pure fixed alkalies, but not with their carbonates: for its other habitudes, and applications, see Spiritus Rectificatus.

ALLII RADIX. L.E.D. Allium Sativum.

Garlic.^[360]

Qualities. This bulbous root has when recent a fœtid smell, and acrid taste, which are extracted by watery infusion; by decoction they are nearly lost; by expression, the root furnishes almost one-fourth of its weight of a limpid juice, and by distillation, an odorous, acrid, essential oil is procured, in which the existence of sulphur may be detected. Garlic has a considerable analogy to squill and onion, and like them, exerts a diuretic, diaphoretic, expectorant, and stimulant operation; (see p. 103). It is a very common domestic remedy for the expulsion of tænia, and it is undoubtedly of advantage in such cases; it is usually administered in the form of a decoction, with milk, on an empty stomach; it is however but rarely used in modern practice, as it possesses no superiority over remedies less nauseous and objectionable; the bruised root, externally applied, is highly stimulant, and rubefacient. Sydenham speaks highly of the application of garlic to the soles of the feet, as a powerful means of producing revulsion from the head. Officinal Preparation. Syrupus Allii. D.^[361]

270ALOES EXTRACTUM. Aloes.

There are three species met with in the shops, viz.

1. Alöe Spicata, L. Socotorina, D. Perfoliata. E. Socrotrine Aloes. Cape Aloes.

2. Alöe Vulgaris.^[362] L. Hepatica, E. D. Common or Barbadoes Aloes.

3. Alöe Cabalina. Fetid, Cabaline, or Horse Aloes. Employed only by Farriers.

Qualities. The above varieties of aloe differ in their purity, and likewise in their sensible qualities; the Socotrine is the purest, it is in small pieces of a reddish brown colour; the Barbadoes is in large masses, of a lighter colour, and having an odour much stronger and less pleasant; the Cabaline is still more impure and less powerful. All the kinds are characterized by an intensely bitter taste, which, in the Socotrine, is accompanied by an aromatic flavour. Chemical Composition. In this there appears to be some obscurity; M. Braconnot (Ann. Chim. tom. 68.) conceives it to be a substance, sui generis, which he terms “bitter resin,” while others regard it as composed of resin, gum, and extractive, the proportions of which are supposed to vary in the different species, but that their peculiar virtues reside in the extractive part. Solubility. It is to the slowness with which aloe undergoes solution in the primæ viæ, that it is indebted for the medicinal properties which distinguish this substance; by boiling water it is dissolved, but on cooling a precipitation ensues, and by long decoction it becomes quite inert; weak acids dissolve it more abundantly than water, but proof spirit is the most perfect solvent: its solubility is increased by the addition of alkaline salts and soaps, but by such a combination it undergoes a material change in its medicinal properties; the bitterness is diminished, its purgative effects impaired, and it ceases to operate specifically upon the large intestines, a fact so far valuable, as it enables us in certain cases to obviate its irritating action upon the rectum. Medicinal Use. Aloe is a bitter stimulating purgative, emptying the large intestines, without making the stools thin; it likewise warms the habit, quickens the circulation, and promotes the uterine and hemorrhoidal fluxes. Dose, gr. v.–xv. No greater effect is produced by a large dose than from one comparatively moderate; its tendency, however, to irritate the rectum renders it, in many cases, an objectionable remedy;^[363] and its sympathetic action on the uterus may occasionally produce mischief, in irritable habits, while in other states it may, for reasons equally obvious, prove beneficial. Forms of Exhibition. The form of pill should be preferred on account of its extreme bitterness, as well as 271being, for the reasons above mentioned, the one most likely to fulfil the intention of its exhibition; for in addition to what has been stated in a preceding part of this work, on the important influence of solubility, it may be here observed that since the aloe does not undergo solution in the stomach, it is admirably adapted for the basis of remedies intended to obviate constitutional costiveness, for in our endeavours to supply the deficiencies of nature by the resources of art, we should at least attempt to imitate the modes of her operation; the natural stimulus of the intestines, the bile, is poured into them below the stomach, and whenever it regurgitates into that organ it produces disease; so it happens with our cathartic medicines, and unless we so modify their solubility that their operation cannot commence until after their passage through the stomach, we shall find that we only increase the evil we are endeavouring to obviate, and that, in addition to the torpor of the intestinal canal, we shall induce the stomach to participate in the disease, or excite a morbid fretfulness of that organ which will be attended with the most distressing symptoms.^[364] See Formulæ 12, 13, 79, 80, 81. Aloes in combination with assafœtida furnishes an eligible purgative in the dyspepsia of old persons; it is also well calculated to obviate the costiveness so generally produced by Opium, (Form: 11, 12, 13.) See also p. 162. Officinal Preparations. Pulv: Aloes comp: L. Pil: Alöes cum Myrrha. L.E.D. Pil: Aloes comp: Pil: Alöes cum Assafœtida. E. Pil: Aloes cum Colocynthide. E. Pil: Cambogiæ comp: (B.M.) L. Pil: Rhei. comp: (F) E. Pil. Scammon, cum Aloe. D. Decoctum Aloes comp: L. Extractum Aloes purificatum. L.D. Extractum Colocynthidis comp: L.D. (F) Tinct: Alöes L.E.D. Tinct: Alöes comp: L.E.D. Tinct: Alöes Ætherea, E. Tinct: Benzoin: comp: (G) L.E.D. Tinct: Rhei et Aloes E. Vinum Alöes. L.E.D. Adulterations. It is frequently adulterated with common resin, but the fraud more generally committed is that of mixing with, or substituting the inferior species for the Socotrine, but the Barbadoes Aloes may, independent 272of its want of aromatic flavour, be distinguished from the Socotrine by a simple test, for the latter dissolves entirely in boiling water and alcohol, whereas the former, when treated in a similar manner, leaves a considerable residue; sometimes the Horse Aloes is made to appear so bright and pure, as not to be easily distinguished by the eye even from the Socotrine, but its rank odour, of which no art can divest it, will readily betray the fraud.

ALUMEN. (Super-sulphas Aluminæ et Potassæ.) Sulphas Aluminæ. E.

Alumen. D. Alum.

Qualities. Form, octohedral crystals, whose sides are equilateral triangles; they are slightly efflorescent. Taste, sweet, rough, and acidulous. Chemical Composition. It is a triple, or sometimes a quadruple salt, with excess of acid, consisting of sulphuric acid and alumina, with potass, or ammonia, or frequently both of them; the nature of the alkali however does not in the least appear to affect the properties of alum, although it produces a crystallographic modification; for where potass is present the summit of the crystal will exhibit a truncation. Dr. Ure has lately produced alum with soda, and the combination differs from common alum only in its greater degree of solubility, a property which at once recommends it to the attention of the pharmaceutist and physician. Solubility. A fluid-ounce of cold water dissolves 30 grains, but if boiling four drachms; it is insoluble in alcohol. Incompatible Substances. Alkalies and alkaline salts, after neutralizing the excess of acid, precipitate the alumine. It is also decomposed by carbonate and muriate of ammonia, carbonate of magnesia, and tartrate of potass, by lime-water, acetate of lead, and the salts of mercury, as well as by many vegetable and animal substances, especially galls and kino. It is on this account very injudicious to combine alum with any vegetable astringent with a view to encrease its virtues; thus the “Pulvis Sulphatis Aluminæ compositus” of the Edinburgh college, is less powerful than any of the ingredients of which it is composed; and the addition of alum to the decoction of bark, undoubtedly diminishes its efficacy as an astringent injection. Medicinal Uses. Alum is internally a powerful astringent, in hæmorrhages and inordinate fluxes, and is externally useful for repellent and astringent lotions, gargles, and collyria. Dioscorides and Hippocrates praised its effects as a lotion in various kinds of ulcers, and particularly in sores of the mouth, and in spongy, swelled gums. Van-Helmont was the first person who employed alum in uterine hemorrhage, and the success of the practice very considerably enhanced his reputation. Boerhaave’s astringent powder for the ague consisted of Alum and Nutmeg with the addition of Armenian bole. Dose, gr. x. In large doses it is liable to excite nausea, and to act upon the bowels. Nutmeg or some aromatic should therefore be joined with it. Forms of Exhibition. In solution, or in substance made into pills with extract; (Form: 53, 56,) it is sometimes given with advantage in the form of whey (Alum-whey—Serum Aluminosum) made by boiling ʒij with a pint of milk, and then straining, the dose of which is a wine glass full; (Form; 54.) By briskly agitating a drachm of alum with the white of an egg, a coagulum is formed, (Alum curd of Riverius; Albumen. Aluminosum) which is 273serviceable in some species of ophthalmia, when applied between two pieces of thin linen rag.^[365] As alum is not decomposed by sulphate of lime, hard water may be safely used for its solution. It has the effect of retarding, and in some instances of preventing, the acetous fermentation in vegetables; thus when added to common paste it prevents its becoming sour; animal substances, as glue, are preserved by it in a similar manner. It has also the property of clearing turbid water, wine, and spirituous liquors, for which purpose it is extensively employed. Officinal Preparations. Liquor Alum: co. L. Pulv: Alum: co. E.

Alumen Exsiccatum, L. Ustum. D. Dried Alum. By the action of heat alum undergoes watery fusion, yields its water of crystallization, and loses more than one third of its weight; if the heat be too intense, or long continued, it is deprived of a great part of its acid. It has been recommended in doses of a scruple, in cholic, when it has been said to operate gently upon the bowels, and to relieve the pain: I have myself experienced this good effect when the cholic has been produced by the action of lead: Dr. Grashuis, a Dutch Physician, first recommended its use in Cholica Pictonum. The preparation however is principally used as an external application, having a degree of escharotic power, which renders it serviceable in venereal chancres, as well as in other ulcers having weak and spongy granulations; it is also very frequently employed to destroy fungous excrescencies, but it should be remembered that, as it owes such power to an excess of acid, unless it be carefully prepared, it must be inefficient. It ought to redden syrup of violets.

Alumen Rupeum. Roche or Rock Alum. This variety was originally brought from Roccha, formerly called Edessa, in Syria, in fragments of about the size of an almond, covered with an efflorescence of a pale rose colour; that however which is now sold under this name is common English alum, artificially coloured. It is unimportant.

Alumen Romanum. Roman Alum is in irregular octohedral masses, powdery on the surface; it is the purest kind, and contains no ammonia in its composition.

AMMONIACUM. L.E.D. (Heracleum Gummiferum.)

Ammoniac.

Qualities. Form, masses composed of fragments, of tears, yellow on the surface, and white within; Taste, a nauseous sweet, followed by a bitter flavour; Odour, faint but not unpleasant. Specific gravity, 1·200. Chemical Composition. Gum-resin, gluten, and some volatile matter. Solubility. It is partly soluble in water, vinegar, alcohol, æther, and in the solutions of the alkalies; when triturated with water a milky liquor is formed, which is a solution of gum holding the resin in suspension, and if the yolk of an egg be employed the mixture is more permanent; water appears to be its proper solvent. Uses. Stimulant, antispasmodic, and expectorant: in large doses gently purgative and sometimes diuretic; after 274the exhibition of smart purgatives, in combination with rhubarb, it proves valuable in mesenteric affections by correcting the viscid secretion of the intestines; dissolved in nitric acid, it is said to prove an excellent expectorant in cases where large accumulations of purulent or viscid matter exist with feeble and difficult expectoration. See Form: 140. Forms of Exhibition. In solution, see Mist: Ammoniac: it may also be given when dissolved in the Liquor ammoniæ acetatis; ʒij of the former may be dissolved in ℥iij of the latter; or it may be exhibited in pills with bitter extracts, myrrh, and other gum-resins; if rubbed with camphor a mass is at once produced very suitable for pills; vinegar renders it soft, and adapts it for plasters. Dose, grs. x to xxx. Officinal Preparations. Mist: Ammoniac: L.D. Pil: Scillæ co: L.E. (B) Emplast: Ammoniac: L. Emplast: Gummos: E. Emplast: Ammoniac: cum Hydrargyro. L. Adulterations. Two varieties are met with in the market, that in tears, guttæ ammoniaci, ought to be white, clear, and dry; and that in lumps, lapis ammoniaci, which sells for one-third the price of the former, being very impure, is generally adulterated with common resin, for which it may be purified by softening the mass in a bladder which is immersed in boiling water, and straining it while fluid.

AMMONIÆ SUB-CARBONAS. L. Carbonas Ammoniæ. E.D.

Sub-carbonate of Ammonia.

Qualities. Form: white, semi-transparent masses, of a striated or crystalline aspect, which, on exposure to air effloresce; Odour, pungent and peculiar; Taste, acrid but cooling. Chemical Composition. It will be found to vary materially in its composition according to the temperature employed for its preparation; the quantity of alkali varying from 20 to 50 per cent. Mr. Phillips considers the Sub-carbonate of ammonia to be a Sesque-carbonate, composed of 3 atoms of carbonic acid, 2 atoms of ammonia, and 2 of water; or that it is a definite compound of Carbonate and Bi-carbonate, one atom of each, with two atoms of water; one hundred parts, by experiment, consist, of 54·2 carb: acid, 29·3 Ammonia, and 16·5 water; if we consider it as a Sesque-carbonate, its constitution, according to Dr. Wollaston’s scale, will be 55·72 Carbonic Acid, 29 Ammonia, 15·28 water. Solubility. According to Duncan it is soluble in twice its weight of cold water; Mr. Phillips states four times; the mean of these will be found nearly correct. Its solubility however is increased by increase of temperature, but when dissolved in boiling water it effervesces, and undergoes a partial decomposition; it is quite insoluble in alcohol, and hence on the addition of spirit to a strong solution, a dense coagulum is produced. Incompatible Substances. It is decomposed by acids, fixed alkalies, and their sub-carbonates, lime, solution of muriate of lime, magnesia, alum, super-tartrate of potass, and all the acidulous salts, sulphate of magnesia, acetate, sub-muriate, and oxy-muriate of mercury, acetate, and sub-acetate of lead, and the sulphates of iron and zinc. If it be added to decoctions and infusions they must be previously cooled. Forms of Exhibition. Since by exposure to air its virtues are impaired, it ought not to be kept in powdered mixtures; in the form of pill it is preserved much longer, especially if it be combined with some vegetable extract. Uses. It is stimulant, antispasmodic, diaphoretic, powerfully antacid, exceeding in this respect the 275fixed alkalies, and in large doses it is emetic. It is highly useful as a stimulant in those gastric affections which supervene habits of irregularity and debauchery; combined with opium it affords a powerful resource in protracted diarrhœa attended with debility of the alimentary canal: and in cases of muscular atony so frequently witnessed, as the sequela of chronic rheumatism, ammonia, in large doses, offers the best remedy; I have moreover witnessed the beneficial effects of this remedy in hoarseness depending upon relaxed states of the throat. In typhus fever it has been particularly recommended by Huxham, Pringle, and many other physicians, and some have considered it superior to any other stimulant upon such occasions. It is also useful in syncope and hysteria, in the form of smelling salts;^[366] with respect to its application for making saline draughts, see Acid: Citricum: Dose, grs v to ℈j: to produce emesis ʒss. See Form. 48, 49, 83, 152. Officinal Preparations. Liquor Ammoniæ sub-carbonatis, L. Liquor Ammoniæ acetatis (I) L.E.D. Liniment: Ammoniæ Sub-carbonatis. L. Cuprum Ammoniatum, (I) L.E.D. Adulterations. This salt ought to be entirely volatilized by heat; if any thing remain it may be considered impure; it ought also to be free from all fetor; should this not be the case it may be corrected by subliming it in conjunction with powdered charcoal; there is at present a large quantity of this impure article in the market, which has been manufactured from the residue sold by the gas light companies.^[367] When long exposed to the air, it becomes opaque and friable, and the excess of ammonia, upon which its odour depends, escapes, carbonic acid is absorbed, and an inodorous bi-carbonate remains, consisting of carbonic acid 55·70, Ammonia 21·52, and water 22·76, or 2 atoms of carbonic acid, 1 atom of ammonia, and 2 atoms of water.

AMMONIÆ MURIAS. L.E. Sal Ammoniacum. D.

vulgo Sal Ammoniac.

Qualities. Form, dense striated concavo-convex cakes which are persistent in the air, or crystallized conical masses; in this latter form it generally contains other salts, especially muriate of lime, which render it deliquescent. Taste, bitter, acrid, and cool. Chemical Composition. In consequence of the present unsettled opinions respecting the nature of muriatic acid and ammonia, and the changes which they undergo by combination with each other, the composition of this salt is involved in some obscurity. According to Dr. Thomson, it consists of equal volumes of muriatic acid gas and ammoniacal gas, although he has subsequently observed that from the peculiar properties of the substance, it may be a compound of Chlorine and Ammonium (the hypothetical base of ammonia.) 276Unlike all the other ammoniacal salts, it does not undergo decomposition by heat. Solubility, f℥j of water at 66° dissolves about two drachms and a half; at 212° it dissolves its own weight; it is also soluble in 4½ parts of alcohol; its solution in water is accompanied by considerable reduction of temperature. Incompatible Substances. The sulphuric and nitric acids unite with the ammonia, and disengage the muriatic acid, whilst ammonia is disengaged by the action of potass and its carbonate, carbonate of soda, lime, magnesia, &c. which combine with its muriatic acid; with oxy-muriate of mercury it combines and increases its solubility, see Hydrarg: Oxy-murias. When united with acetate of lead, it decomposes it, and a muriate of lead is precipitated. It is obvious also that nitrate of silver, and all the metallic salts whose bases form insoluble compounds with muriatic acid, are incompatible with it. Uses. Rarely employed as an internal remedy, externally it is employed in lotions, either for the cold produced during its solution, in which case it should be applied as soon as the salt is dissolved, or for the stimulus of the salt, on which principle it acts as a powerful discutient in indolent tumours (Form. 146.) It is also an ingredient in a very useful plaster, in which it undergoes chemical decomposition; this plaster consists of Soap ℥j, lead plaster, ʒij, liquified together, to which, when nearly cold, are added of muriate of ammonia finely powdered ʒss. The alkali of the soap enters into combination with the muriatic acid of the muriate of ammonia, and forms thereby muriate of potass, or soda, and ammoniacal gas (on which the virtue of the plaster depends) is slowly but abundantly liberated, acting as a powerful stimulant and rubefacient: it should be applied immediately after it is formed, and be renewed every twenty-four hours, otherwise the intention is lost; (Pharmacopœia Chirurgica.) I have often applied this plaster with evident advantage to the chest in pulmonary affections, and I wish to recommend it to the attention of practitioners. It is very useful also in that rheumatic affection of the muscles of the chest, which is so frequently met with in persons in advanced life; during the last winter I was consulted in two cases where the distress after exercise was so considerable as to resemble angina pectoris. Officinal Preparations. Ammoniæ Sub-carbonas (I). L.E.D. Liquor: Ammoniæ (K). L. Aqua Ammoniæ. E.D. Hydrarg: præcip: alb: (I). L. Alcohol Ammoniatum, (I). E.D. Ferrum Ammoniat: (G). L.E.D. Adulterations. This salt, if pure, may be entirely volatilized by a low heat; the sulphate of ammonia however, as it is also volatile, cannot be discovered except by the muriate of baryta, which will indicate its presence by a copious precipitate.

AMYGDALÆ DULCES. {Varieties of “Amygdalus Communis.”

AMYGDALÆ AMARÆ. {Sweet and Bitter Almonds.

Qualities. The sweet almond is inodorous, and has a sweet, bland taste; the bitter almond,^[368] when triturated with water, has the odour 277of the peach, and a pleasant bitter flavour. Chemical Composition. Boullay has lately confirmed the analogy which Proust had stated to exist between the emulsion of sweet almonds and human milk, viz. the former consists of sweet oil 54, albumen 24, sugar 6, gum 3, with traces of acetic acid; the indigestible property of the almond depends upon its albuminous matter. The bitter almond, in addition to those constituents, contains hydro-cyanic acid, (Prussic acid,) in union with a peculiar volatile oil, upon which its narcotic properties depend; but this deleterious element is so modified by the natural state of combination in which it exists with sweet oil and albumen, that they may be eaten without inconvenience. The bitter almond has long been regarded as an antidote to drunkenness; Plutarch states it as a fact on the authority of his physician Claudius. Other bitters were however supposed to possess similar powers in this respect, hence the Poculum Absinthiatum to which we have before alluded. See page 79. Both sorts of almonds yield by expression a large quantity of fixed oil, which is perfectly mild. See Oleum Amygdal. The water distilled from the bitter almond, when strongly impregnated, has been found to exert a deleterious action on the human body, and to prove fatal to many animals. Solubility. By trituration with water a milky mixture is produced, (an emulsion), for which purpose the sweet almonds should be previously freed from their cuticle, (blanched), and this ought to be performed by infusing them in tepid water; for when hot it separates a portion of their oil, as is evident from their being thus rendered yellow, and the emulsion is therefore more liable to ferment, and be decomposed. ℥ij of almonds saturate about f℥vj of water; since however this extemporaneous preparation is tedious and inconvenient, the London Pharmacopœia very judiciously directs a confection to be ready prepared, ʒj of which, when triturated with f℥j of water, immediately forms an elegant emulsion. See Mistura Amygdal. Almonds form a useful intermedium for suspending in water many substances which are of themselves not miscible with it, as camphor, and several of the gum-resins; they also assist in the pulverization of refractory substances, as Ipecacuan, &c. Officinal Preparations. Confectio Amygdalarum. L. Emulsio Camphoræ (M.) E. Emulsio Acaciæ Arab: E. D.

Amygdalæ Placenta. Almond Cake is the substance left after the expression of the oil, which when ground forms Almond Powder, so generally used for washing the hands.^[369]

Oil of Bitter Almonds. For obtaining this oil, the expressed cake is submitted to distillation, when a highly volatile, pungent, oil passes over. See Oleum Amygdalæ Amaræ.

278AMYLUM. L.E.D. Starch. (Triticum Hybernum Amylum.^[370])

Qualities. Form, white columnar masses; Odour and Taste, none. Chemical Composition. Fecula is one of the proximate principles of vegetable matter, and Starch is the fecula of wheat.^[371] Solubility. It is soluble in boiling water, forming with it a semi-transparent, insipid, inodorous, and gelatinous paste, very susceptible of mouldiness, but which is retarded by the addition of alum; it is insoluble, but falls to powder in cold water; nor is it dissolved by alcohol or ether; although potass dissolves starch, yet the solution of it is not disturbed by potass, carbonate of potass, nor ammonia, but an alcoholic solution of potass produces a precipitate; acetate of lead, and infusion of galls occasion also precipitates. Starch is susceptible of several interesting and important changes; thus, if it be exposed to heat until its colour becomes yellow, its properties are so far altered that it is no longer insoluble in cold water; and according to the experiments of Saussure, if it be mixed with water, a spontaneous decomposition takes place, and a quantity of sugar is formed, amounting in weight to one half of the starch employed, in addition to which a peculiar gummy matter results, and a substance intermediate between gum and starch, to which the name of Amidine has been given. Starch moreover is convertible into saccharine matter by the agency of sulphuric acid. Uses. Being demulcent it is generally employed as a vehicle for the exhibition of opium in the form of enema. The ordinary blue starch is coloured by a solution of smalt and alum, and is unfit for medicinal use; formerly it was tinged yellow with saffron or turmeric, but this went out of fashion on the execution of the famous midwife Mrs. Collier, who was hanged in a ruff starched with that colour. Officinal Preparations. Mucilago Amyli. L.E.D. Pulvis Tragacanth: comp: (B) L. Pil: Hydrargyri (M) E. Troschisi Gummos: E.

It has been lately observed that Iodine is a delicate test of the presence of starch; if a drop or two of a solution of this substance in alcohol be added to an aqueous solution of starch, a blue compound is formed which eventually precipitates. Iodine may therefore be employed for ascertaining the goodness of starch, a test which is very important, for much of what is sold under the name of starch, does not possess its peculiar characters; it ought however to be stated, that the blue indication is prevented from taking place by a variety of different bodies, as Arsenious acid, corrosive sublimate of mercury, &c. &c.

279ANETHI SEMINA. L. E.

(Anethum Graveolens. Semina.) Dill Seed.

These seeds when dry have an aromatic sweetish odour, and a warm pungent taste, qualities residing in an essential oil, which is extracted by distillation with water and by digestion with alcohol; the bruised seeds yield their flavour to boiling water by simple infusion. The seeds are but rarely used. The distilled water is a valuable carminative for children.

ANISI SEMINA. L. E. D.

(Pimpinella Anisum. Semina.) Anise Seeds.

Like the dill seeds, warm and carminative; water extracts very little of their flavour; rectified spirit the whole. It may be remarked in this place that the value of aniseed, as well as all those seeds which yield essential oil by distillation, may be estimated by their specific gravity, the heaviest yielding the largest proportion of oil; a chrondrometer employed by corn-chandlers might be very conveniently applied to such a purpose.^[372] The seeds imported from Spain, which are smaller than the others, contain most oil, and are to be preferred.

ANTHEMIDIS FLORES. L. E.

(Anthemis Nobilis.) Chamomile Flowers.

Qualities. The Odour of the flowers is strong and fragrant; Taste, bitter and aromatic, with a slight degree of warmth. Chemical Composition. The active principles are essential oil, resin, and bitter extractive. Solubility. Both water and alcohol take up the active parts of the flowers; hot water, by infusion, dissolves nearly one-fourth of their weight, but boiling dissipates the essential oil, on which account they should never form an ingredient in a decoction. Uses. The flowers given in substance are said to have cured intermittents; they are however but rarely used; externally they are applied in fomentations. See Infusum Anthemidis. Officinal Preparations. Decoctum Anthemidis nobilis. E.D. Infusum Anthemidis. L.^[373] There is a great variety in the quality and price of chamomile flowers; those which are large and whitish are to be preferred as the freshest; by keeping they become invalid, and are deprived of their aromatic principle and essential oil. They are always inferior in wet seasons. The double flowered varieties are also less powerful than the single kind, since the qualities reside in the disc florets.

280ANTIMONII SULPHURETUM. L.

Sulphuret of Antimony.

Qualities. This article appears in the market in conical loaves, which are dark grey externally, but internally possess a bladed structure and considerable brilliancy; the Edinburgh and Dublin colleges direct this substance to be levigated with water, and kept in the state of powder; it should however never be purchased in that form, as it is not unfrequently adulterated with sulphuret of lead, whereas it cannot contain such admixture when its form is characteristically crystalline and bladed. Chemical Composition. Antimony 100, Sulphur 35·572. From the time of Basil Valentine to the present, this preparation has been known in the market by the name of Antimony, a name which it is evident can only with propriety be applied to the pure metal. Solubility. It is insoluble in water and alcohol; since however it is slightly acted upon by vegetable acids, cups were formerly made of it, which imparted to wine that stood in them for some time, an emetic quality.^[374] Uses. It is principally employed for the preparation of the other antimonial combinations, for which purpose it is more eligible than the metal itself, as being less contaminated with metallic impurities. Its medicinal energies depend altogether upon the state of the stomach, and must therefore be extremely uncertain; when it meets with any acid in the stomach, it acts with extreme violence, a circumstance which requires precaution. It was formerly much more employed as an Alterative than at present. Stoll recommends its use in chronic rheumatism, and advises its union with Myrrh. In the treatment of affections of the skin it has been long used, both singly, and in union with other substances, such as Conium, Dulcamara, Guaiacum, &c. In Scrophulous diseases, connected with cutaneous eruptions, or ulcerations, it has been a favourite remedy with many practitioners, and it forms the basis of several foreign Nostrums. In times of remote antiquity it was used by females as a black pigment for staining the eye-lashes, a custom which continues to this day in the east.^[375] It is at present given to horses mixed with their food, to make their coats smooth, and very large doses may be given to these animals without producing any deleterious effects. Officinal Preparations. Dr. Black constructed a table representing a view of all the preparations whose basis was antimony; many of these however have fallen into disuse, and the nomenclature of all is changed. The following arrangement of the medicines prepared from the sulphuret 281of antimony,^[376] is presented to us by Mr. Thomson, in his London Dispensatory. 1. By trituration, Sulphuretum Antimonii Præparatum. E.D. 2. By the Action of Heat with Phosphate of Lime, (oxidized) Pulvis Antimonialis, L.D. Oxidum Antimonii cum Phosphate Calcis. E. 3. By the Action of Alkalies, (oxidized), Antimonii Sulphuretum Præcipitatum. L.E. Sulphur Antimoniatum Fuscum. D. 4. By the Action of Acids, (oxidized,) Antimonii Oxydum. L. Oxydum Antimonii Nitromuriaticum. D. Antimonium Tartarizatum. L. Tartris Antimonii, olim Tartarus Emeticus. E. Tartarum Antimoniatum, sive Emeticum, D. Vinum Antimonii Tartarizati. L. Vinum Tartaritis Antimonii. E.

Adulterations. The importance of employing this article in a state of great purity, for the preparation of so many active and valuable medicines, is obvious. It ought to be entirely volatilized by a read heat; Lead is discovered by its imparting to the antimony a foliated instead of a bladed texture, and from not being vaporizable; Arsenic, by the garlic odour emitted when thrown upon live coals; or by the numerous tests mentioned under the history of that article; Manganese and Iron, from not being vaporizable, and from other tests: the most usual adulteration is black oxide of iron, or the scoriæ of that metal, “Smithy dust.”

ANTIMONII SULPHURETUM PRÆCIPITATUM. L. E.

Sulphur Antimoniatum Fuscum. D.

Precipitated Sulphuret of Antimony.

Qualities. Form, a brilliant orange coloured powder; Taste, slightly styptic, but inodorous. Chemical Composition. Very complicated attractions are exerted during the preparation of this substance; the result of which is an hydro-sulphuret of Oxide of Antimony, with excess of sulphur. Solubility. It is quite insoluble in water. Uses. According to the dose, it is diaphoretic, cathartic, or emetic; it is, however, less certain than many other preparations, and, unless in combination with mercury, for cutaneous affections, is not very often employed. Incompatible Substances. All acids and acidulous salts increase its emetic properties; when therefore acid is suspected to prevail in the primæ viæ, it should be combined with soap, magnesia, (Form: 128,) or aromatic confection; on the contrary, the confection of roses, and vehicles containing acids, should be carefully avoided. Form of Exhibition. Pills. Dose, grs. 1 to v. Officinal Preparations. Pilulæ Hydrargyri Sub-Muriatis (H) L. Adulterations. It is often sophisticated with chalk and other extraneous matter; it ought not to effervesce with acids; it should be entirely vaporizable by heat, and its colour should be that of bright orange. A spurious article is vended, which consists of sulphur and sulphuret of antimony coloured with Venetian red.

282ANTIMONIUM TARTARIZATUM. L.

Tartris Antimonii. E. Tartarum Antimoniatum. D.

Tartar Emetic.^[377]

Qualities. Form, crystals whose primitive form is the regular tetrahedron, although it assumes a variety of secondary forms. Colour, white. Odour, none. Taste, slightly styptic and metallic; on exposure to the air, the crystals slightly effloresce and become opaque; thrown upon burning coals, they become black and afford metallic antimony. Chemical Composition. This is involved in much doubt and obscurity; it is stated in the various dispensatories to be a triple salt, consisting of tartaric acid, oxide of antimony,^[378] and potass, and which therefore, says Mr. Thomson, on the principles of the reformed nomenclature, ought to be termed a tartrate of antimony and potass. The truth of these views, however, is extremely questionable. I am inclined to believe with Gay Lussac, that in the various metalline compounds, of which super-tartrate of potass is an ingredient, this latter substance acts the part of a simple acid; an opinion which receives much support from the great solvent property of cream of tartar, and from the striking fact that it is even capable of dissolving various oxides which are insoluble in tartaric acid, of which the protoxide of antimony is an example. According then to this view, tartar emetic is a salt composed of bi-tartrate (super-tartrate) of potass, which acts the part of an acid, and protoxide of antimony: from the experiments of Mr. Phillips, it would appear that 100 parts of the bi-tartrate will dissolve 70 of the protoxide. In this state of doubt it must be admitted that no name can be more appropriate than Antimonium Tartarizatum, and the London College have therefore properly disregarded the suggestions which have been offered for changing its name. Solubility. Much discrepancy of opinion exists upon this subject, owing probably to the variations and incidental impurities to which the salt is liable. Dr. Duncan, who selected very pure specimens for examination, states that it is soluble in three times its weight of water at 212°, and in fifteen at 60°. This solution, when the salt is pure, is perfectly clear and transparent, but if long kept, unless a portion of spirit be added, it undergoes decomposition; a precipitate indeed sometimes takes place very rapidly, but this is generally tartrate of lime, an incidental impurity, derived from the super-tartrate of potass. Incompatible Substances. Mineral 283Acids, Alkalies, and their Carbonates, most of the Metals, Soaps, Hydro-Sulphurets, and many infusions and decoctions of bitter and astringent Vegetables, e. g. f℥j. of the decoction of yellow bark is capable of completely decomposing ℈j of this salt, and of rendering it inert.^[379] Berthollet has accordingly recommended the immediate exhibition of this decoction when an overdose of the salt has been taken; and Orfila has given a very satisfactory case in which this antidote succeeded. Infusion and tincture of galls throw down curdled and inert precipitates of a dirty white colour, inclining to yellow. Rhubarb is equally incompatible: the extract of this substance therefore never ought to be employed in forming pills of tartar emetic: but it deserves notice that this salt is not decomposed by the infusions of gentian or wormwood. The Alkaline Sulphates, provided they be perfectly neutral, produce no disturbance in solutions of tartar emetic, and therefore cannot be considered incompatible with them; if there be any excess of acid, as in alum, bi-sulphate of potass, &c. then its decomposition is effected, and a white insoluble sulphate of antimony is precipitated. It appears therefore that the famous “Emeto-purgative” of the French school, consisting of sulphate of soda, and tartarized antimony in solution, is by no means the unchemical mixture which some have considered it to be, and that it really produces its effects from the operation of its original ingredients, and not from that of the compounds (Sulphate of Antimony, Tartrate of Soda, and Sulphate of Potass) which have been erroneously supposed to result. Forms of Exhibition. Solution is its best form, see Liquor Antimonii Tartarizati. Dose. It either vomits, purges, or sweats, according to the quantity exhibited; thus gr. 1/4 will, if the skin be kept warm, promote a diaphoresis; gr. ½ will procure some stools first, and sweating afterwards; and gr. j will generally vomit and then purge, and lastly sweat the patient; in very minute doses, as gr. 1/10 or 1/12 combined with squill and ammoniacum, it acts as an expectorant, see Formulæ 1, 2, 3, 8, 60. It is decidedly the most manageable, and the least uncertain of all the antimonial preparations, and the practitioner would probably have but little to regret, were all the other combinations of this metal discarded from our pharmacopœias. Some authors have considered this substance as possessing sedative powers, independent of its nauseating and diaphoretic effects. It undoubtedly acts upon the heart, and controls the force of the circulation in fevers, without occasioning any other sensible effect. Mr. Brodie, after having given large doses of this salt to animals, found that the heart beat very feebly, and although artificial respiration was kept up, it soon ceased to act altogether. Lenthois of Montpellier advises small doses of it in incipient phthisis, and it would on some occasions appear to diminish the febrile excitement. The following is the form in which Dr. Lenthois recommends it to be exhibited upon such occasions. He directs a grain of Tartarized Antimony to be dissolved in eight table spoonsful of distilled water, which are to be added to six or eight pints of water, and to be taken as common drink. Tartar emetic, when triturated with lard, in the proportion of ʒiss or ʒij to ℥j of the latter, forms a very powerful rubefacient, occasioning a pustular eruption on the skin, and proving very serviceable in deep-seated inflammation; or the application may be made by dusting a piece of adhesive plaster with tartarized antimony, 284taking care to leave a margin untouched that it may more firmly adhere. Dr. Jenner, in a late Essay on the influence of artificial eruptions on certain diseases, recommends the following formula for such a purpose.—℞. Antimonii Tartarizati (in pulverem subtilem trit.) ʒij—Unguenti Cetacei ʒix;—Sacchari albi^[380] ʒj;—Hydrargyri Sulphureti Rubri gr. v. M. ut fiat Unguentum. The Pustules which are produced by the inunction have been generally compared to variolous pustules, they are, however, in general much smaller, not so red at the base, nor so tense and white when fully suppurated. They are very painful. In Hooping cough, frictions with this ointment upon the region of the stomach have been greatly extolled. By this application, says Dr. Jenner, we can not only create vesicles, but we can do more,—we have at our command an application which will at the same time both vesicate and produce diseased action on the skin itself, by deeply deranging its structure beneath the surface. This is probably one cause why the sympathetic affection excited by the use of Cantharides, and those changes produced by Tartar Emetic are very different. The eruption should be kept up for some time, either by the re-application of small portions of the diluted tartaremetic ointment, to the affected part, or by other gently stimulating ointments. Should they become much irritated and very painful, a soft bread and milk poultice will in general afford relief, without interfering with the progress of the eruption. Officinal Preparations. gr. j. is contained in f℥ss of Liquor Antimonii Tart: L. and Vinum Tartratis Antimonii. E.^[381] Adulterations. It should be always purchased in its crystalline form; and a solution of it in distilled water ought to furnish a copious gold coloured precipitate with sulphuret of ammonia; a precipitate soluble in nitric acid, with acetate of lead; and a white and extremely thick precipitate, dissolving with facility in pure nitric acid, with lime water. If the crystals deliquesce, the presence of other salts may be inferred. M. Sexullas, in a memoir of which there is a copious extract in the Journal de Pharmacie for 1821, has shewn that all the antimonial preparations used in medicine, except carefully crystallized Tartar Emetic, contain more or less arsenic, which metal was originally combined with the antimony in the ore, and has continued pertinaciously associated with it through all its modifications.