Chapter III: Their Form of Prescription (4)

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 of 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.

ANTIMONIUM 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 Acids, 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, taking 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.

AQUA. _Water._

Water, from its extensive powers as a solvent, never occurs in a state of absolute purity, although the nature and degree of its contamination must necessarily vary according to circumstances and situation. It is generally found holding earthy matter in a state of mechanical suspension, or saline and other bodies in chemical solution. The usual varieties of common water are classed and defined by Celsus; and modern chemists have not found any reason to reject the arrangement. “_Aqua levissima pluvialis est; deinde fontana, tum ex flumine, tum ex puteo; posthæc ex nive, aut glacie; gravior his ex lacu; gravissima ex palude._”

1. RAIN WATER. _Aqua Pluvialis_, when collected in the open fields, is certainly the purest natural water, and consequently of the least specific gravity; the bodies which it holds in solution are, carbonic acid, a minute portion of carbonate of lime, with traces of muriate of lime. DEW is said to be water saturated with air. Rain water ought, however, to be boiled and strained whenever it is collected near large towns; Hippocrates gives this advice, and M. Margraaf of Berlin has shewn the wisdom of the precaution by a satisfactory series of experiments.

2. SPRING WATER. _Aqua Fontana_, in addition to the substances detected in rain water, generally contains a small portion of muriate of soda, and frequently other salts; but the larger springs are purer than smaller ones, and those which occur in primitive countries, and in siliceous rocks, or beds of gravel, necessarily contain the least impregnation. An important practical distinction has been founded upon the fact, that the water of some springs dissolves soap, whilst that of others decomposes, and curdles it; the former has been termed _soft_, the latter _hard_ water; soft water is a more powerful solvent of all vegetable matters, and is consequently to be preferred for domestic as well as medicinal purposes; the brewer knows well from experience how much more readily and copiously _soft_ water will dissolve the extractive matter of his malt. Horses by an instinctive sagacity always prefer soft water, and when by necessity or inattention they are confined to that which is _hard_, their coats become rough and ill-conditioned, and they are frequently attacked with the gripes. Pigeons also refuse hard water when they have been accustomed to that which is soft.[382]

3. RIVER WATER. _Aqua ex Flumine_, being derived from the conflux of numerous springs and rain water, generally possesses considerable purity; that the proportion of its saline ingredients should be small, is easily explained by the precipitation which must necessarily take place from the union of different solutions; it is, however, liable to hold in suspension particles of earthy matter, which impair its transparency, and sometimes its salubrity; this is particularly observed of the Seine, the Ganges, and the Nile.[383]

4. WELL WATER. _Aqua ex Puteo_, is essentially the same as spring water, being derived from the same source; it is, however, more liable to impurity from its stagnation, or slow infiltration;[384] hence our old wells furnish much purer water than those which are more recent, as the soluble particles are gradually washed away. Mr. Dalton observes that the more any spring is drawn from, the _softer_ the water becomes.

5. SNOW WATER. _Aqua ex Nive_, has been supposed[385] to be unwholesome, and in particular to produce bronchocele, from the prevalence of that disease in the Alps, but it does not appear upon what principle its insalubrity can depend; the prejudice however is a very ancient one, for Hippocrates observes that snow or ice water is unwholesome, in consequence of its finer particles being evaporated and lost during its solution: it appears to differ only from rain water in being destitute of air, to which water is certainly indebted for its briskness, and perhaps for many of its good effects upon animals and vegetables. The same observations apply to _Ice Water_.

6. LAKE WATER. _Aqua ex Lacu_, is a collection of rain, spring, and river waters, contaminated with various animal and vegetable bodies, which from its stagnant nature have undergone putrefaction in it.

7. MARSH WATER. _Aqua ex Palude_ being the most stagnant is the most impure of all water, and is generally loaded with decomposing vegetable matter.

To what extent the impurities of water are capable of influencing its salubrity, has been a subject of interesting inquiry from the age of Hippocrates to the present day. To many of these natural contaminations, too much importance has been certainly attached; it is an affected refinement to suppose that the presence of minute portions of such earthy and calcareous salts, as generally occur in solution, can impart any noxious quality to water;[386] whilst on the contrary, animal and vegetable impurities, or earthy bodies in a state of mechanical suspension, cannot fail to prove injurious, and must be regarded as the true “SCELERA AQUARUM.” Guided by false analogies many have supposed that they recognised the origin of all calcareous diseases in the earthy impurities of water; the researches however of chemistry have removed this delusion, by demonstrating that the substances found in water never enter into the composition of urinary calculi.[387] Metallic and other accidental contaminations are necessarily highly injurious, and the water in which their presence is suspected, should be submitted to the most careful examination.

For the purification and preservation of water numerous methods have been adopted; the mechanical impurities may be removed by filtration, which is performed through porous stones, or alternate layers of sand or charcoal; muddy water may be also cleared by adding a few grains of alum to each pint,[388] and in that proportion, the water is not rendered in the least disagreeable: when water has contracted a putrid smell, it may be rendered sweet by agitating it with a small portion of magnesia, or with black oxide of manganese, in the proportion of 1½ parts to 250 parts of water. Dr. Black observes that nitrate of silver, which is one of the most antiseptic substances known, will preserve water from putrefaction for ever, and that it may at any time be separated therefrom in a few minutes by adding a small lump of common salt; this fact in itself is curious, but the experiment is too hazardous to be recommended. Dr. Alston prefers lime, as a preservative of the water, and proposes to remove it by the addition of a carbonate of magnesia; Dr. Henry has however found that it is more economically precipitated by the introduction of a current of carbonic acid into the cask. As that peculiar property of water which is termed _hardness_, generally depends upon the presence of _sulphate of lime_, the addition of an alkaline carbonate twenty-four hours previous to its being used, will be found to restore it, or if it should depend upon _supercarbonate of lime_, long ebullition without any addition will be found sufficient for its cure.

Water when kept for a long time in casks, especially on long voyages, is partially decomposed, and a volume of carburetted hydrogen is evolved,[389] imparting to such water the peculiar smell and taste which characterise it; this decomposition may in a great degree be obviated by charring the interior of the water casks; it is, however, prevented in the Navy by substituting iron tanks for wooden vessels. In Pharmacy it ought to be remembered that whenever common water is employed it should not be _hard_; filtered rainwater maybe recommended as the most eligible on such occasions.

AQUA DESTILLATA. L.E.D. Distilled Water.

QUALITIES. _Taste_, vapid from the absence of air, and slightly empyreumatic in consequence probably of the presence of a small quantity of extractive matter which has undergone partial decomposition; a fluid-ounce weighs 454½ grains. MEDICINAL USE. In extemporaneous prescriptions, distilled water should be always ordered whenever the formula contains any of the following substances:—_Acidum Sulphuricum_; _Acidum Citricum_; _Antimonium Tartarizatum_; _Argenti Nitras_; _Cuprum Ammoniatum_; _Ferrum Tartarizatum_; _Hydrargyri Oxy-murias_; _Liquor Ammoniæ_; _Liquor Plumbi Sub-Acetatis_; _Liquor Potassæ_; _Plumbi Acetas_; _Solutio Muriatis Barytæ_; _Vinum Ferri_; _Zinci Sulphas_; _Ferri Sulphas_. Distilled water ought also to be employed in preparations where much water is evaporated, as in the formation of extracts, since the residual matter of common water will remain mixed with the product of the process, and uselessly add to its bulk, or even in some cases produce in it chemical changes; unless however under such circumstances, common water purified by filtration should be ordered, as the air which it contains imparts to it a pleasant and sprightly flavour. In making infusions or decoctions, it is very important that the water should be free from those impurities which impart to it _hardness_, and which render it a far less powerful solvent of vegetable matter, nor indeed can resinous substances be mixed with such water, even when assisted by a mucilaginous medium. On which account, in prescribing emulsions, it may perhaps be prudent to direct the employment of distilled water. TESTS OF ITS PURITY. Its transparency ought not to be disturbed by the addition of nitrate of silver, or muriate of baryta.

AQUA MARINA. Sea Water.

Until the late able researches of Dr. Murray, we possessed but an imperfect knowledge of the composition of sea water; it is not therefore surprising that the analysis performed by different chemists should be found to be so materially at variance; the true cause of such discordance is now easily understood, for it appears, that in the examination of a mineral water or any compound saline solution, the substances obtained from it are not necessarily the original ingredients, but frequently the products of new combinations established by the operation of analysis, and that consequently the nature of the result obtained may vary according to the modes in which such analysis has been conducted, or even according to the degree of dilution in which the saline substances exist.[390] The elements of the salts contained in a pint of sea water are _Lime_ 2·9, _Magnesia_ 14·8, _Soda_ 96·3, _Sulphuric Acid_ 14·4, _Muriatic Acid_ 97·7, total 226·1 grains, and supposing these elements to be combined in the modes which Dr. Murray’s views appear to establish, the saline contents of a pint of sea water may be expressed as follows, _Muriate of Soda_ 159·3, _Muriate of Magnesia_ 35·5, _Muriate of Lime_ 5·7, _Sulphate of Soda_ 25·6 grains, total 226·1 grains; besides such saline contents, it is contaminated with various animal and vegetable bodies, in consequence of which it becomes, when long kept, highly offensive; it ought also to be stated that Dr. Wollaston has discovered the presence of a minute proportion of potass in sea water; and Dr. Marcet has more lately detected ammonia in combination with muriatic acid. MEDICINAL USE. As a cathartic, a pint is the ordinary quantity, which should be taken in the morning, at two doses, with an interval of half an hour between each; this quantity contains half an ounce of purgative salt, of which about three-fourths are muriate of soda, but it is much more active than a similar portion of any artificial combination. In procuring sea water for medicinal purposes, there is a precaution, the importance of which experience has suggested to me, that it be not hastily drank on the beach, before the particles of sand, with which under such circumstances it is generally mixed, are allowed to subside; from the neglect of this precaution I have witnessed serious consequences. The most important advantages of sea water are derived from its external use as a bath.

AQUÆ DESTILLATÆ. L.D.

AQUÆ STILLATITIÆ. E. _Distilled Waters._

These are waters impregnated with the essential oils of vegetables, and are principally designed as grateful vehicles for the exhibition of more active remedies; ample directions for preparing them are given in the several Pharmacopœias, and if they be rectified by redistillation they may be kept for several years; the usual mode of preserving them is by adding spirit, which has also the incidental advantage of preventing them from being frozen during the winter season. Some recommend a film of the essential oil to be diffused over the water’s surface. They may be extemporaneously prepared by adding to water what have been called _Essences_, which consist of essential oil and alcohol, or by rubbing any essential oil with ten times its weight of sugar, or, what answers still better, of magnesia: when however they are so prepared they never retain their transparency. The college, in the present Pharmacopœia, have directed the distillation off the essential oil, as well as off the recent herb; this alteration is one of practical convenience. The properties of each water may be learnt by referring to the vegetable from which it is distilled.

AQUÆ MINERALES. Mineral Waters.

Although all waters that flow from the earth, are, as they contain mineral bodies in solution, strictly speaking, _mineral_ waters, yet this term is conventionally applied to such only as are distinguished from spring, lake, river, or other water, by a peculiarity in colour, taste, smell, or any obvious properties, or by the medicinal effects which they produce, or are known to be capable of producing.

To the medical practitioner the history of these waters is most interesting and instructive, involving highly important subjects of chemical and physiological inquiry. These waters are without doubt indebted for their medicinal virtues to the operation of the substances which they hold dissolved, but this is so materially aided by the peculiar state of dilution in which they exist, as well as by the mere bulk and temperature of the water itself, as to render extremely doubtful the success of every attempt to concentrate their powers by evaporation. To what extent dilution may modify the chemical condition of saline solutions has been satisfactorily demonstrated by the researches of Dr. Murray (see _Aqua Marina_), and to what degree an increase in the solubility of any remedy may influence its medicinal properties has been considered at some length in the first part of this work, (_page 172_.) It is certain that, in general, soluble salts are capable of exerting a much more powerful effect upon the animal economy, than those which are insoluble; on which account, the earthy muriates, especially that of lime, are amongst the most active ingredients of mineral waters. Although chemical analysis has frequently from its own imperfection failed in ascertaining their presence, it seems probable that _muriate of lime_ and _sulphate of soda_ exist in all those springs that furnish, by the usual methods of examination, _sulphate of lime_ and _muriate of soda_; for the same reasons it is equally probable that iron, which in certain waters has been supposed from the analysis to exist as a _carbonate_, is in its native solution a true _muriate_; this is undoubtedly the fact with respect to the Bath waters. Is it then surprising, that medical practitioners should hitherto have failed in their attempts to emulate, by artificial arrangements, the medical efficacy of active and mineral springs? For the investigation of the true composition of mineral waters the researches of Dr. Murray furnish a simple and elegant formula. _Determine by precipitants the weight of the acids and bases, suppose them united in such a manner that they shall form the most soluble salts, and these salts will constitute the true saline constituents of the water under examination._

Mineral Waters admit of being divided into four classes, viz.

1. ACIDULOUS; owing their properties chiefly to carbonic acid; they are tonic and diuretic, and in large doses produce a transient exhilaration; the most celebrated are _Pyrmont_, _Seltzer_, _Spa_, _Carlsbad_, and _Scarborough_.

2. CHALYBEATE; containing iron in the form of _sulphate_, _carbonate_, or _muriate_;[391] they have a styptic, inky taste: _Hartfell_ near _Moffat_, _Peterhead_, _Tunbridge_, _Brighton_, _Cheltenham_, _Bath_, _Lemington Priors_, _Castle Horneck_, near _Penzance_, &c.

3. SULPHUREOUS WATERS derive their character from sulphuretted hydrogen, either uncombined, or united with lime, or an alkali: _Engien_, _Aix la Chapelle_, _Harrowgate_, _Moffat_.

4. SALINE; mostly purgative, and are advantageously employed in those hypochondriacal and visceral diseases that require continued, and moderate relaxation of the bowels; _Cheltenham_, _Leamington_, _Seidlitz_, and all brackish waters.

Some springs, as those of _Bath_, _Matlock_, and _Buxton_, owe their virtues rather to temperature than to any other cause, and others, as _Malvern_, to the diluent power of the water.

In the Codex Medicamentarius of Paris, formulæ are introduced for the preparation of several of the more distinguished mineral waters, under the head “_Aquæ Minerales Arte Factæ_.”[392]

ARGENTI NITRAS. L. Nitras Argenti. E.D.

_Fused Nitrate of Silver_, olim, _Lunar Caustic_.

QUALITIES. Fused nitrate of silver is in small cylinders of a dark grey colour, and presenting, when broken across, a crystalline structure. _Odour_, none; _Taste_, intensely bitter, austere and metallic; it tinges the skin indelibly black; when perfectly free from copper, it is not deliquescent. CHEMICAL COMPOSITION; oxide of silver 70, nitric acid 30, or one atom of oxide and one atom of acid. SOLUBILITY. In an equal weight of water, at 60°; it is also soluble in alcohol. The solution readily yields transparent colourless crystals, the primary form of which is a _right rhombic prism_. INCOMPATIBLE SUBSTANCES. _Fixed alkalies_ and _alkaline earths_, the _muriatic_, _sulphuric_, and _tartaric_ acids, and all the salts which contain them; _Soaps_, _arsenic_, _hydro-sulphurets_, _astringent vegetable infusions_, _undistilled waters_. The solutions of nitrate of silver are not disturbed by ammonia, the _ammoniuret_ being very soluble; the carbonate of ammonia, however, produces a precipitation. Nitrate of silver tinges the skin and hair black, and has been frequently employed for the latter purpose;[394] it likewise forms the basis of permanent ink.[395] MEDICINAL USES. Tonic, antispasmodic, and escharotic; it is said to prove efficacious in epilepsy, but during a trial for several years in the Westminster hospital, I never could discover its virtues; many of the cases in which it has been supposed to have been successful, probably derived advantage from the purgative medicines which were simultaneously administered. It possesses a bitter taste, and it has been said to act like vegetable bitters upon the digestive organs, and to offer a resource in dyspeptic complaints. It is principally useful as an external application, and may be considered as the strongest and most manageable caustic that we possess;[396] whilst in solution it acts as a useful stimulant in indolent ulcers; and being possessed of the power of coagulating animal matter, it does not spread to any extent, and is therefore extremely convenient where a large eschar is to be avoided. A weak solution of this metallic salt has lately been strongly recommended by a French surgeon, as a remedy for piles of long standing; it also forms an excellent lotion to excite the weak granulations of fungous ulcers. It is, moreover, said to be highly useful as an injection in cases of puriform discharges from the ear; before we direct however such an application, it is highly necessary that we should ascertain the tympanum to be entire, or the liquid may escape into the internal ear, and occasion very alarming irritation; an event which unhappily occurred, not long since, in the case of a noble duke of high military renown. FORMS OF EXHIBITION. For internal use, in pills made with crumb of bread, with the addition of some sugar, to prevent the mass from being too hard. Dose, gr. 1/8, gradually increased to gr. j. ADULTERATIONS. _Copper_ may be always suspected when it deliquesces, and is to be immediately detected by its solution assuming a blue colour, when supersaturated with ammonia. The sticks should be preserved in closely stopped phials, and covered with soft and dry paper. ANTIDOTE. When this substance has been taken in excess, muriate of soda is its true antidote; indeed, so completely does it decompose, and separate it from water, that if a saturated solution of nitrate of silver be filtered through common salt, it may be afterwards drunk with impunity. This circumstance alone, would of necessity render nitrate of silver a very uncertain remedy; and yet it is evident that the basis of this salt is occasionally absorbed, for there are several cases upon record, in which the oxyd of silver has been deposited in the rete mucosum, and given a purple hue of a very singular appearance to the patient; I have lately witnessed an instance of this kind in a lady who had taken large doses of the nitrate, for the purpose of curing a dyspeptic complaint; and several other similar cases stand recorded in different works.

ARMORACIÆ RADIX. L.E. (_Cochlearia Armoracia_ )

Raphanus Rusticanus, D. _Horse[397] Radish Root._

QUALITIES. _Taste_, hot and acrid; _Odour_, pungent. CHEMICAL COMPOSITION. All its virtues depend upon an essential oil. SOLUBILITY. Both water and alcohol extract its active principles, but they are dissipated by decoction. MEDICINAL USES. As a stimulant in paralysis it is often useful; Sydenham found it successful in dropsies which were consequent on intermittent fevers; Cullen recommends a syrup made with the infusion of horse radish, to remove that species of hoarseness which depends upon local relaxation; Dr. Withering extols an infusion of this root in milk as a cosmetic both safe and effectual. INCOMPATIBLE SUBSTANCES. Alkaline Carbonates; _Oxy-muriate of Mercury_; _Nitrate of Silver_; the _Infusion of Galls_ and _of Yellow Cinchona Bark_, produce precipitates with the infusion of this root. FORMS OF EXHIBITION. In substance, scraped or swallowed whole, or in infusion.[398] DOSE of the substance ʒj, of an infusion f℥ij. See _Infus Armoraciæ comp_. OFFICINAL PREPARATIONS. _Infusum Armoraciæ comp:_ L. _Spiritus Armoraciæ comp:_ L.D.

ARSENICUM ALBUM. (Acidum Arseniosum.)

Oxydum Arsenici. E. Arsenicum. D. _White Arsenic_.

_Arsenious Acid._ vulgo _Arsenic_.

QUALITIES. _Form_, shining semivitreous lumps, breaking with a conchoidal fracture, and when reduced to powder, bearing some resemblance to white sugar; _Taste_, acrid and corrosive, but not in any degree corresponding with its virulence, leaving an impression of sweetness. _Specific gravity_ 3·7; it is volatilized at the temperature of 383° _Fah:_ and by a strong heat is vitrified into a transparent glass capable of crystallizing in tetrahedra with truncated angles, or rather in octohedra. In the state of vapour it is quite inodorous, although it is asserted in many chemical works of authority to yield a smell like that of garlic; the fact is that the alliaceous or garlic-like smell is wholly confined to _metallic_ arsenic in a state of vapour, and whenever the arsenious acid seems to yield this odour, we may infer that its decomposition has taken place; this happens when it is projected upon ignited charcoal, or when heated in contact with those metallic bodies which readily unite with oxygen, as _Antimony_ and _Tin_. It is stated by Orfila and other chemists, that if it be projected upon heated copper the alliaceous odour is evolved. This assertion is undoubtedly true, but the fact requires to be explained with more precision, or we may fall into an important error respecting it. The phenomenon takes place only when the copper is in a state of ignition, at which temperature its affinity for oxygen enables it to reduce the arsenious acid; for I find by experiment that if a few grains of this substance be heated on a plate of copper, by means of a spirit lamp or blow-pipe, no odour is perceptible, for the whole of the acid is dissipated before the copper can acquire a sufficiently exalted temperature to deoxidize it. If the arsenious acid be heated on a plate of zinc, the smell is not evolved until the metal is in the state of fusion; if instead of these metals we employ in our experiments those of gold, silver, or platinum, no alliaceous smell whatever is produced, at any temperature. It however deserves particular notice, that the flame of the spirit lamp is itself capable of decomposing the oxyd, in consequence of the operation of its hydrogen: a fact which is very likely to betray the chemist into the fallacious belief that the oxyd does yield the odour in question.[399] It is probable that arsenical vapours which yield this peculiar odour are less noxious than those which are inodorous, but I am not aware that the knowledge of this fact can be applied to any purpose of practical importance.[400] CHEMICAL COMPOSITION. This substance possesses many of the essential habitudes of an acid, as for instance, that of combining with the pure alkalies to saturation; it is therefore very properly denominated _Arsenious Acid_. It may be farther acidified by distilling it with nitrous acid, and the compound which results is a white concrete substance termed _Arsenic Acid_; from experiments on the quantity of oxygen absorbed by metallic arsenic, during its conversion into these two compounds, instituted by Proust and Davy, it appears that the _arsenious_ acid consists of about 25 of oxygen and 75 of metal, and the _arsenic_ acid of 33 of oxygen and 67 of metal; or, the quantity of metal being the same, that the oxygen in the latter compound is to that in the former nearly as three to two. SOLUBILITY. We have but lately been set right upon this point; Klaproth has shewn that it requires for its solution 400 parts of water at 60° and only 13 at 212°, and moreover, that if 100 parts of water be boiled on the arsenious acid, and suffered to cool, it will retain three grains in solution, and deposit the remainder in tetrahedral crystals; this fact shews the importance of employing boiling water in every chemical examination of substances supposed to contain arsenic. It is soluble in alcohol and oils, the former taking up two per cent.; with lime water it produces a white precipitate of _arsenite of lime_, which is soluble in an excess of arsenious acid; with magnesia it forms a soluble _arsenite_, which proves very virulent. The poisonous effects of arsenious acid are so amply detailed in medical works,[401] that it would be superfluous to dwell upon them in this place; it may however be interesting and useful to record an account of the pernicious influence of arsenical fumes upon organized beings, as I have been enabled to ascertain in the copper smelting works, and tin burning-houses of Cornwall. This influence is very apparent in the condition both of the animals and vegetables in the vicinity; horses and cows commonly lose their hoofs, and the latter are often to be seen in the neighbouring pastures crawling on their knees, and not unfrequently suffering from a cancerous affection in their rumps, whilst the milch cows, in addition to these miseries, are soon deprived of their milk; the men employed in the works are more healthy than we could _a priori_ have supposed possible; the antidote upon which they all rely with confidence, whenever they are infested with more than an ordinary portion of arsenical vapour, is _sweet oil_, and an annual sum is allowed by the proprietors in order that it may be constantly supplied; this opinion is not solitary, for Tachenius relates that the poisonous effects, such as convulsions, gripes, and bloody stools, with which he was seized from exposure to the fumes of arsenic, were relieved by milk and oil.

It deserves notice that the smelters are occasionally affected with a cancerous disease in the scrotum, similar to that which infests chimney-sweepers, and it is singular that Stahl in describing the putrescent tendency in the bodies of those who die from this poison, mentions in particular the gangrenous appearance of these parts. It is a very extraordinary fact that previous to the establishment of the copper works in Cornwall, the marshes in their vicinity were continually exciting intermittent fever, whereas since that period a case of ague has not occurred in the neighbourhood; I have heard it remarked by the men in the works, that the smoke _kills_ all fevers. The fact is here stated without any other comment than that the agricultural improvements which have taken place in the district, are not sufficient to afford any clue to the explanation of the circumstance. MEDICINAL USES. Much has been said upon this subject, and the propriety and safety of its exhibition has been often questioned; there can be no doubt but that the greatest circumspection is required in the practitioner who administers it, and it ought not, in my opinion, to be employed until other remedies have failed; that it is capable of accumulating in the system is very evident, and this, in certain habits, may predispose the patient to serious diseases; the form in which it is most manageable and least dangerous, is that of solution. See _Liquor Arsenicalis_. Some practitioners have exhibited it in substance, made into pills, by rubbing one grain with ten of sugar, and then beating the mixture with a sufficient quantity of crumb of bread to form ten pills, one of which is a dose. The Chinese and other oriental nations form the sulphuret of arsenic (_realgar_) into medical cups, and use lemon juice, after it has stood some hours in them, by way of cathartic. As an external application, arsenic has long been extolled in the cure of cancers; the caustic so extensively used under the sanction of the late Mr. Justamond in cases of open cancer, consisted of two parts of Antimony, and one of Arsenious acid, fluxed together in a crucible, and afterwards levigated, and reduced to the requisite degree of mildness by the addition of powdered Opium.[402] But it deserves notice in this place, that repeated experiments have proved that arsenic kills[403] more rapidly when applied externally to an abraded part, than when internally administered. See page 132. _Lionardo di Capoa_ relates the case of a child killed by the violent vomiting and purging arising from a slight wound made in the head by a comb, wet with oil, in which Arsenic had been infused for the purpose of killing vermin; and we have numerous instances on record, where the application of arsenical cerates and ointments has been followed by violent and dangerous symptoms. We also learn from the different historians of the Plague of London, that the arsenical amulets which were worn, as preservatives, on that occasion, were sometimes attended with deleterious consequences; _Crato_ (Epist. 168.) observed an ulcer of the breast produced by them. _Vernascha_, violent pains and syncope. Amongst the foreign authors who have related cases of poisoning by the external application of Arsenic we may mention _Desgranges_ (_Recueil Period: de la Société de Med: de Paris_, T. vi. p. 22.) who records the history of a chambermaid, poisoned by having rubbed her head with an arsenical ointment for the purpose of destroying vermin; and _Roux_ (_Nouveaux Elemens de Med: Operat. par. J. P. Roux_,) who confessed to have killed a young girl of eighteen by an application of the “_Pate Arsenicale_” to a cancerous breast. To the Empirics of our own times we are indebted for many fatal illustrations of the subject. Since the last edition of this work, a Lady applied to a well known Quack, distinguished for his impudent pretensions in the treatment of cancer, and submitted to a caustic application to the breast. In a short time paralysis ensued, and the application was discovered to contain a large proportion of Arsenic, and that the disease, for the cure of which it had been applied, was _not_ cancer. A somewhat analogous case occurred under the care of a bold empiric in the neighbourhood of St. George’s Fields, who undertook to remove the deformity of bow legs in a dandy drawing-master! by _rasping the shin bones_, and applying arsenic to the surface of the wound; in consequence of which, in addition to extensive local mischief, the unhappy dupe became paralytic. It is also necessary to inform the practitioner that Arsenious acid has been known to produce poisonous effects when applied to the _unbroken_ skin; a case of this nature is related by Desgranges, in the sixth volume of the _Recueil Periodique de la Soc: de Med_: another may be found in the 22d volume of the _Acta Germanica_ (1730); and Renault obtained similar results in his experiments on animals. When the system is under the influence of arsenic, the following symptoms will appear, viz. thickness, redness, and stiffness of the palpebræ, soreness of the gums, ptyalism, itching over the surface of the body, restlessness, cough, pain in the stomach and bowels, head-ache, and I have also occasionally noticed paucity of urine, and even stranguary, a fact of which I find no mention in other authors. Strange as it may appear, _Arsenic_ has been inhaled, together with the vapours of frankincense, myrrh, and those of other gums during a paroxysm of asthma! This extraordinary practice arose from the practitioner mistaking the gum juniper, or _Vernix_ of the Arabians, which by their medical authors was prescribed in fumigations under the name of _Sandarach_, for the Σανδαρακη of Aristotle, which was a sulphured of arsenic.

ADULTERATIONS. It is frequently sophisticated with chalk, gypsum, or sulphate of barytes; the fraud is instantly detected by its not being entirely volatilized by heat, or by any insoluble residuum occurring in preparing the _Liquor Arsenicalis_, according to the directions of the pharmacopœia. To many the adulteration of so active a substance may seem unimportant, but in consequence of its being thus rendered a medicine of variable activity, it is one of the most dangerous frauds which can be committed; a very unpleasant circumstance lately occurred from such a cause in one of our public institutions: arsenic had been obtained from the shop of a respectable chemist, who had not usually supplied the establishment, for the purpose of preparing the arsenical solution: the article happened to be less adulterated than that which had been previously employed; the solution however was prepared in the usual way, and the usual dose was continued, when the patients were soon seized with violent pains in the bowels, and the cause was not detected until by an examination of the bottle the usual sediment was not discovered.

ANTIDOTES. Late researches have shewn that _sulphuret of potass_, on which physicians have placed so much reliance, merits no confidence. The great indication to be fulfilled in all cases of poisoning is to excite vomiting, and to administer liquids which are the least liable to act as solvents of the acrid matter, on which account lime water presents itself as a very appropriate fluid. The subject, however, is very fully considered in the first part of this work, to which I am very desirous of directing the attention of the medical practitioner; see _Antidotes_.

_Methods of detecting the presence of Arsenious Acid._

1. _By its reduction to a metallic state._ Mix a portion of the suspected powder with three times its weight of _black flux_;[404] put the mixture into a thin glass tube, hermetically closed[405] at one end, about eight inches in length, and one-fourth of an inch in diameter; should any of the powder adhere to the sides of the tube, it must be carefully brushed off with a feather, so that the inner surface of its upper part may be perfectly clean and dry; the closed end of the tube, by way of security, may be thinly coated with a mixture of pipe-clay and sand,[406] but this operation is not absolutely necessary; the open extremity is to be loosely plugged with a piece of paper; the coated end must be now heated on a chaffing dish of red hot coals, when the arsenic, if present, will sublime, and be found lining with a brilliant metallic crust the upper part of the tube; a portion of this reduced metal, if it be arsenic, will, when laid on heated iron, exhale in dense fumes, which are characterised by a strong smell of garlic. Mr. Phillips has lately stated that the tube may be sufficiently heated, for the purpose of metallization, by means of a spirit lamp.[407]

It merits particular notice, that in reducing by the above process the arsenious acid to the state of metal, the presence of potass in the flux is very essential, since it forms immediately an _arsenite of potass_, and thereby fixes the arsenious acid, and prevents it from being volatilized before the temperature is sufficiently high to enable the charcoal to decompose it; an ignorance of this fact has not unfrequently proved a source of disappointment and fallacy.

Another method of identifying _white arsenic_ by metallization, is to form at the moment of its reduction, an alloy with copper, which is easily effected in the following manner,—Mix the suspected powder with black flux, as in the former experiment, and place the mixture between two polished plates of copper, bind them tight together by iron wire, and expose them to a low read heat; if the included substance contained arsenic, a silvery white stain will be left on the surface of the copper, which is an alloy of the two metals. If in this, as in the former experiment, charcoal be employed without the addition of a fixed alkali, the result may, for the same reason, prove unsatisfactory. But, with whatever care this experiment is conducted, it is, to say the least, a clumsy and unsatisfactory test, and ought never to be relied upon.

2. _By the application of certain Reagents, or Tests, to its Solutions._

A great and important question has arisen in medical jurisprudence, whether any chemical proof of the presence of _white arsenic_, short of its actual reduction to the state of metal, can be depended upon, or ought to be received as evidence in the courts of criminal law. After a full experimental investigation of the subject, and an impartial review of all the facts which bear upon the question, I feel no hesitation in declaring it to be my conviction, that _white arsenic may be detected without any fear of fallacy_, _by a proper application of certain tests_, and that the contrary opinion is entirely founded in error, and unsupported by experiment, as will more fully appear in the sequel.[408]

(A) _Fused Nitrate of Silver_, or _Lunar Caustic_—For this test we are indebted to Mr. Hume of London, who first gave it to the public in the Philosophical Magazine for May 1809, vol. xxxiii. His method of applying it is as follows: into a clean Florence flask introduce two or three grains of the suspected powder, to which add about eight ounces of rain or distilled water, and heat the solution until it begins to boil, then while it boils frequently shake the flask, and add to the hot solution a grain or two of sub-carbonate of potass, agitating the whole to make the mixture uniform. Pour into a wine glass about two table spoonsful of the solution, and touch the surface of the fluid with a stick of lunar caustic. If arsenic be present, a beautiful yellow precipitate will instantly proceed from the point of contact, and settle towards the bottom of the glass as a flocculent and copious precipitate.

By this test the 60th part of a grain may be satisfactorily recognised in two ounces of water. The presence of some alkali is essential to the success of the experiment, since arsenious acid is unable, by the operation of simple affinity, to decompose the nitrate of silver.[409] The validity of this test has been questioned on the following grounds, which shall be fairly examined in order.