Chapter III: Their Form of Prescription (5)

OBJECTION 1. _The alkaline phosphates are found to produce precipitates with silver, analogous in colour and appearance to the arsenite of silver._ This is undoubtedly the case when the experiment is performed in the manner just stated, but there are other reagents which will immediately distinguish these bodies, as will be seen under the history of the _Ammoniuret of silver_; I have also shewn that there is a mode of so modifying the application of the silver test itself, that no error or doubt can arise in the use of it from the presence of phosphoric salts.[410] My method consists in conducting the trial on writing paper, instead of in glasses, thus—drop the suspected fluid on a piece of white paper, making with it a broad line; along this line a stick of lunar caustic is to be slowly drawn several times successively, when a streak is produced of a colour resembling that known by the name of _Indian Yellow_; and this is equally produced by the presence of arsenic and that of an alkaline phosphate, but the one from arsenic is rough, curdy, and flocculent, as if effected by a crayon, that from a phosphate homogeneous and uniform, resembling a water-colour laid smoothly on with a brush; but a most important and distinctive peculiarity soon succeeds, for in less than two minutes the phosphoric yellow fades into a _sad green_, and becomes gradually darker, and ultimately quite black; while, on the other hand, the arsenical yellow remains permanent, or nearly so, for some time, when it becomes brown. In performing this experiment the sun-shine should be avoided, or the transitions of the colour will take place too rapidly. It would be prudent also for the inexperienced operator to perform a similar experiment on a fluid known to contain arsenic, and on another with a phosphoric salt, as a standard of comparison. In this way the nitrate of silver, without the intervention of any other test, is fully capable of removing every ambiguity, and of furnishing a distinguishing mark of difference between the chemical action of arsenic and that of the phosphates. Mr. Hume states that he has repeated this experiment to his entire satisfaction,[411] and that, in a late unfortunate case of poisoning, he derived considerable information by its application. The laborious author of the London Dispensatory accepts it as an excellent test, but observes that it is rendered more luminous by brushing the streak lightly over with liquid ammonia immediately after the application of the caustic, when, if the arsenic be present, a bright queen’s yellow is produced which remains permanent for nearly an hour; but that when the lunar caustic produces a white-yellow before the ammonia is applied, we may infer the presence of some alkaline phosphate, rather than that of arsenic. One of the great advantages of this test is the very small quantity that is required for examination; it would be well therefore for the operator to perform the experiment in both ways on a separate paper.

OBJECTION 2. _The Muriates produce precipitates with silver so copious and flocculent as to overcome every indication which the presence of arsenic would otherwise afford._ Dr. Marcet proposes to obviate this difficulty, by adding to the fluid to be examined dilute nitric acid, and then cautiously applying the nitrate of silver until the precipitation ceases; in this way the muriatic acid will be entirely removed, whilst the arsenic, if it be present, will remain in solution, and may be rendered evident by the affusion of ammonia, which will instantly produce the yellow precipitate in its characteristic form. This mode however it must be confessed appears complicated, and requires some chemical address for its accomplishment; it should be also known that the yellow precipitate thus produced is not always permanent, for it is soluble in the nitrate of ammonia formed during the process. Under these circumstances, it is surely preferable to precipitate at once from the suspected fluid all the substances which nitrate of silver can effect, and then to expose the mixed and ambiguous precipitate so obtained, to a low heat in a glass tube, when the arsenious acid will be immediately separated by sublimation. In this way the presence of muriates may even in certain cases be serviceable, especially if the quantity of arsenic be minute; for by increasing the bulk of the precipitate we shall decrease the difficulty of its examination. By this process, also, I should propose to meet the embarrassments which arise from the influence of various animal and vegetable substances, as milk, broth, wine, &c. so frequently present in the suspected liquid, and which are known to alter the character of the arsenical indications. In this case, however, we must not rely upon any single precipitant; after having thrown down all that is precipitable by the silver test, the supernatant liquid should be decanted, slightly acidified by acetic acid, and submitted to the action of Sulphuretted Hydrogen; when, should any precipitate occur, it must be separated and added to the former. Dr. Christison has demonstrated the importance of this proceeding by shewing that the precipitates, occasioned by the Ammoniurets of silver and copper, are soluble in certain vegetable infusions.[412] M. Orfila proposes to remove the difficulties and embarrassments, occasioned by the colouring matter of different media, by the application of _Chlorine_, so as to change the colour to a shade that will not offer any optical impediment to the characteristic indications of the different tests. I am ready to admit that such a mode of proceeding may, on certain occasions, assist the accomplished chemist in his analysis, but in the hands of a person less accustomed to chemical manipulation, I hesitate not to declare that it is subject to fatal fallacies;[413] whereas, by precipitating the whole, and submitting the precipitate to the process of sublimation, we shall avoid every source of error. Why then should we attempt to pursue our game through the windings of a labyrinth, when a direct road lies before us, by which we may at once drive it into the open plain? Mr. Phillips has recently proposed the addition of animal charcoal (_Ivory Black_) for the purpose of destroying the colouring matter. He found that by mixing this substance with the _Liquor Arsenicalis_, that the colouring matter was so completely destroyed in a few minutes, that the test of nitrate of silver, or any other might be readily applied. This experiment was repeated with Port wine, gravy soup, and a strong infusion of onions, and he succeeded in these cases in procuring a solution sufficiently colourless for the application of the most delicate reagents. It might be supposed, adds Mr. Phillips, that the Phosphoric acid which the animal charcoal contains, might have some share in the production of the yellow precipitate with silver; he found, however, that water, or wine, which was merely digested on the animal charcoal, produced no effect with the nitrate of silver, except a slight precipitate of chloride; and this even, was prevented by lixiviation. I have, however, a serious objection to offer to this proposal. Animal charcoal, by some mode of operation not understood, possesses the property of removing certain substances from their solution in water; I have already noticed this effect with respect to Lime water, (see p. 247, _note_), and I have lately found that it takes place with very dilute solutions of Arsenic.[414] Hence charcoal, as we shall presently find, may be employed for the purpose of detecting minute portions of arsenic.

OBJECTION 3. _Chromate of potass produces, with Nitrate of Silver, a yellow precipitate which, when placed side by side with one produced by Arsenious acid, cannot be distinguished by colour or appearance from it_. This fact has lately been announced by Dr. Porter of the University of South Carolina. (Silliman’s Journal, iii, 355.) But as the presence of chromate of potass can never be suspected in any research after arsenic, in cases of forensic interest, the fact is of no importance to the physician.

Where the Arsenious acid is mixed with vegetable matter, and it becomes difficult to separate it by filtration, the whole may be evaporated to dryness, taking great care that the heat applied for such a purpose never exceeds 250° _Fah:_ or we shall lose the arsenic by volatilization. The residue thus obtained may then be submitted to a higher temperature, in a subliming vessel, in order to procure the arsenious acid in its pure state. Should the arsenious acid have, in the first instance, been dissolved in oil, Dr. Ure proposes to boil the solution in distilled water, and to separate the oil afterwards by the capillary action of wick threads. If the arsenious acid be mixed with resinous bodies, oil of turpentine may be employed as their solvent, which will leave the arsenic untouched. Dr. Black directed the application of alcohol for this purpose, but this is obviously improper, since arsenious acid is soluble in that fluid.

It has been stated that, in consequence of the inability of arsenious acid to decompose nitrate of silver by simple elective attraction, the presence of an alkali becomes indispensable in the examination, for which purpose Dr. Marcet has suggested the superior advantages which will attend the use of ammonia, in cases where the arsenic has not been previously combined with a fixed alkali, since it does not, when added singly, decompose nitrate of silver; a circumstance which in using the fixed alkalies is very liable to occasion fallacy. This led Mr. Hume to improve his original plan, by forming at once a compound, which he calls the _Ammoniaco-nitrate of silver_, but which may with more propriety be designated as an _Ammoniuret_.[415] This is a triumph in the art of analysis; for whilst it obviates the necessity of ascertaining the exact proportion of alkali required in each experiment,[416] it possesses the valuable property of not in the least disturbing the phosphate of soda.

(B.) _Sulphate of Copper._ Like the preceding test, this also requires, for its success, that the arsenious acid should be combined with some alkali, in which case, by the operation of double elective attraction, an arsenite of copper is thrown down of a very striking and characteristic colour, being that of the well-known pigment called _Scheele’s green_; if arsenic be not present in the liquid so assayed, and a fixed alkali has been employed, the result will be a delicate _sky-blue_, instead of the _grass-green_ precipitate.

Mr. Hume avails himself also of the peculiar property of ammonia to form a metallic salt, and has employed it with copper: he takes the sulphate or acetate of that metal, and by the same process as that described for the preparation of an ammoniuret of silver, forms another test. In using this, however, care must be taken that it be not too highly concentrated, for in that state it will not produce precipitation. Much controversy has taken place on the subject of sulphate of copper as a test for arsenic, and it has been stated, with more confidence than truth, that a _decoction of onions_ has the property of imparting to the copper precipitate, which is produced by a fixed alkali, a colour and appearance analogous to that which is occasioned by arsenic. This opinion was boldly advanced and supported on a most important[417] trial at the Lent assizes for Cornwall in 1817. Since this event an opportunity[418] has occurred which has enabled me to examine this alleged fact, by a fair and appropriate series of experiments, the result of which satisfactorily proved that the opinion was grounded on an optical fallacy, arising from the _blue_ precipitate assuming a _green_ colour, in consequence of having been viewed through a yellow medium.[419] The phosphoric salts may also, under similar circumstances, be mistaken for arsenic, for the intense blue colour of the phosphate of copper will thus necessarily appear green. This instance of optical fallacy is not solitary, for _corrosive sublimate_ has been said to possess the character of an alkali, because it turns the syrup of violets green, whereas this change is to be attributed solely to the combination of the yellow hue of the sublimate with the blue colour of the violet.

Whenever therefore such a source of fallacy can be suspected, the operator would do well to repeat his experiment on white paper, in the manner I have before proposed, and the results which are obtained in glasses should always be examined by day-light, and viewed by reflected and not by transmitted light. The presence of Peroxide of Iron in the Cupreous salt will also impart a green colour to the precipitate produced by an alkali. To obviate any fallacy which might arise from this circumstance, Mr. Phillips proposes to add some pure Potass to the sulphate of copper; if pure, a fine blue precipitate will be thus obtained; to this may be then added the suspected solution, and if Arsenious acid be present, it will then convert this blue precipitate to a green one.

(C.) _Sulphuretted Hydrogen._ This is a very delicate test for arsenic, producing with its solution a beautiful golden coloured liquor, which after a short time lets fall a precipitate. Mr. Phillips,[420] in reviewing the third edition of the present work, has stated, that no such precipitate occurs, but I find that in close, as well as in vessels exposed to the air, it takes place by repose. By this reagent, so small a quantity as 1⁄000,000 may be detected in solution; and it may be also stated in farther proof of the utility of this test, that it is less affected than any other by the presence of animal or vegetable matter. The method of preparing a solution of sulphuretted hydrogen gas is extremely simple. Put into an oil flask about two ounces of undiluted muriatic acid and an ounce and a half of powdered Sulphuret of Antimony; fit a cork to the flask and pass through it the short leg of a small glass tube twice bent at right angles; pass the longer leg of the tube into a phial containing distilled water, and then by the heat of a spirit lamp applied to the flask, sulphuretted hydrogen gas will be abundantly liberated, and though much of it will escape, yet a sufficient quantity will be dissolved by the water. The annexed sketch represents the apparatus proposed by Mr. Phillips, and which will require but little practical skill, either for its construction or use.

But it is not always necessary to prepare a watery solution of Sulphuretted Hydrogen, a stream of the gas, introduced into the suspected liquor by means of the above apparatus, will act with equal delicacy, and possesses, as Dr. Christison has observed, the advantage of not diluting it. Before applying this test, it is necessary to add an acid, if any alkali should exist along with the Arsenic, otherwise no precipitate will take place.

(D.) _Alkaline Hydro-sulphurets._ These bodies do not affect the arsenious solution, unless a few drops of acetic acid be added. To the _Hydro-sulphuret_, or perhaps more properly, _Hydroguretted Sulphuret_, of Ammonia there is an insuperable objection, since this fluid, when diluted, possesses the colour which we expect to produce by the action of Sulphuretted Hydrogen upon Arsenious Acid.

(E.) _Charcoal Powder._ This test was proposed by Mr. A. Thomson, (London Dispensatory, 2nd edition, p. 53.) Into the suspected solution stir a moderate quantity of charcoal powder, allow it to settle, then pour off the supernatant liquor, and when the powder which remains is dry, sprinkle some of it on a red hot poker, when, if the solution should contain Arsenic, the odour of Garlic will be rendered sensible. I have already offered some remarks upon the cause of this phenomenon (_page 304_.)

There are several other tests by which arsenic may be identified. The process described in the Dublin Pharmacopœia for the preparation of _Arsenias Kali_, the arseniate, or rather super-arseniate of potass, which has been long known under the name of “the arsenical salt of Macquer,” has been strongly advised as a collateral proof; it consists in decomposing the nitrate of potass[421] by the arsenious acid, but since this problem requires that the suspected poison should be in a solid and palpable form, it is impossible to examine its pretensions to our confidence, without being reminded of the story so often told to us in our infancy, of catching a bird by laying salt upon its tail.

It is necessary to observe in this place, that the _arseniate_, like the _arsenite of potass_, or that of _ammonia_, is obedient to the silver test, but that instead of the yellow precipitate which is produced by the latter salt, we obtain, by the former, a red or brick-coloured one.

If arsenious acid and quick-lime be heated together in a glass tube, a sudden ignition is occasioned at a certain temperature, when metallic arsenic will sublime, and an arseniate of lime be formed. In this case one portion of the arsenious acid is robbed of its oxygen to complete the acidification of the remainder.

In taking an impartial review of all the evidence which the investigation of this subject can furnish, it must appear to the most fastidious, that the silver and copper test above described are capable, under proper management, of furnishing striking and infallible indications, and that in most cases they will be equally conclusive, and in some even more satisfactory in their results, than the metallic reproduction upon which such stress has been laid, and for this obvious reason, that unless the quantity of metal be considerable,[422] its metallic splendour and appearance is often very ambiguous and questionable. It has to my knowledge happened to a medical person, by no means deficient in chemical address, to ascribe to the presence of arsenic that which was no other than a film of very finely divided charcoal: in this state of doubt the last resource was to ascertain whether it yielded, or not, upon being heated, an alliaceous odour. Surely an unprejudiced judge would prefer the evidence of sight, as furnished by the arsenical tests, to that of smell, as afforded in the last experiment. No one will attempt to deny that it is the duty of the medical practitioner who is called upon to decide so important a question as the presence of arsenic, to prosecute by experiment every point which admits the least doubt; he should also remember that in a criminal case, he has not only to satisfy his own conscience, but that he is bound, as far as he is able, to convince the public mind of the accuracy and truth of his researches; and he fails in his duty if he omits, through any false principle of humanity, to express the strong conviction which the success of his experiments must necessarily have produced in his mind. Let it however be remembered, that the application of chemical reagents on solutions suspected to contain arsenic, so far from throwing any obstacle in the way of the metallic reduction of that body, are the very steps which should be adopted as preparatory to the “_experimentum crucis_,” since the precipitates which are thus produced may be collected, and easily decomposed, as before stated. Those who for judicial purposes may require farther information upon these subjects are referred to the second volume of our work on “_Medical Jurisprudence_.” _Tit: Poisons._

ARSENICI OXYDUM SUBLIMATUM. L.

_Prepared Oxide of Arsenic._

The object of this process is to ensure a pure and uniform oxide; it has been already stated that a more dangerous fraud can scarcely be committed than the adulteration of arsenic; I am therefore not inclined to coincide with Mr. Thomson, and to regard “the present process as superfluous,” and the committee of the college entertained a similar opinion.

ASARI FOLIA. L.E.D. _Asarum Europæum._

Asarabacca Leaves.

QUALITIES. The leaves, when recent, are nauseous, bitter, and acrimonious, and prove violently purgative and emetic, properties which are impaired by keeping. CHEMICAL COMPOSITION, a peculiar acrid principle, not well understood. SOLUBILITY, water by infusion extracts their sensible properties, but they are lost by decoction. USES. As an errhine, Dr. Cullen has remarked that they form the most useful species of this genus of local stimulants. DOSE, gr. iij. to v. repeated every night until the full effect is produced. OFFICINAL PREP. _Pulvis Asari compositus._ E.D.

ASCLEPIAS TUBEROSA.

_Pleurisy root. Radix._

[The root of this plant, which is very abundant in every part of the United States, is the part used in medicine. It has a bitter taste, and its most soluble portions are fecula and a bitter extractive matter. Its best menstruum is boiling water. Its medicinal properties are expectorant and diaphoretic. The diseases in which it has been found useful are catarrh, bronchitis, the passive stage of pneumonia, and in rheumatism. In substance it may be taken in doses from ℈j to ʒss. Of the decoction, made by boiling half an ounce of the root in water, a tea cup full may be taken frequently during the day.]

ASSAFŒTIDA.[423] L.E.D.

Ferula Assafœtida. _Gummi Resina._

QUALITIES. _Form_, small irregular masses, adhering together, of a variegated texture, and containing many little shining tears of a whitish, reddish, or violet hue. _Taste_, bitter and sub-acrid. _Odour_, fœtid and alliaceous, but this latter property is very much impaired by age. CHEMICAL COMPOSITION. Gum (or according to Brugnatelli, _extractive_) 60, resin 30, and essential oil 10 parts. SOLUBILITY. It yields all its virtues to alcohol and æther; if triturated with water it forms a milky mixture, but which is not permanent, unless some intermede be employed for the suspension of the gum-resin; for this purpose egg may be added, in the proportion of one yolk to a drachm of assafœtida, or a permanent mixture may be effected by carefully triturating the gum resin with double its weight of mucilage. If ʒvj of assafœtida be triturated with ʒss of camphor, a mass results of a proper consistence for a plaster; if triturated with carbonate of ammonia, it is easily reduced to powder, but undergoes no other change. FORMS OF EXHIBITION; in mixture or in pills. The Indian physicians have an idea that on account of its stimulating powers, it will, if administered to a pregnant woman, produce abortion. DOSE, gr. v. to ℈j. _Form. 23, 29._ MEDICINAL USES, stimulant, antispasmodic, expectorant, and anthelmintic; in coughs, attended with pulmonary weakness, and a tendency to spasm, it is very beneficial; in cases of flatulent cholic, it has, in the form of enema, acted like a charm; in habitual costiveness it often proves an invigorating aperient, and may be advantageously combined with resinous purgatives in torpor of the bowels connected with nervous symptoms. OFFICINAL PREP. _Mist: Assafœtid:_ L.D. _Tinct: Assafœtid:_ L.E.D. _Spir: Ammoniæ fœtid:_ (=B=) L.E.D. _Tinct: Castori, comp:_ (=B=) E. _Pil: Aloes cum Assafœtid:_ (=G=) E. _Pil: Galbani: comp:_ (=B=) L. _Enema Fœtid:_ D. IMPURITIES. Its characteristic odour should be powerful, and when broken, its fracture ought to exhibit a bluish-red appearance. It ought not to be brittle.

AURUM.

(Auri Murias.) _Muriate of Gold._

[Gold was early used as a medicine. It fell however into total disrepute until its use was a few years since revived in France. Although it has attracted some attention lately, it can hardly be said to have reclaimed a permanent place in the materia medica. The most striking effects which it produces on the system, are an increase of urine and perspiration. It has been recommended in glandular swellings, gleets, schirrus of the uterus, scrofula, and dropsy. It is however as an antisyphilitic remedy that it has been principally celebrated. According to Dr. Chrestien of Montpelier, it would appear that gold was not merely adequate to the cure of syphilis in all its forms, but that it possesses very great advantages over mercury—It does not affect the gums, nor does it in any way disturb the general health of the patient. Notwithstanding this warm recommendation of Dr. Chrestien, it is still doubtful whether gold is adequate to the cure of syphilis. The best form in which the gold can be given is that of the muriate, prepared according to the directions of the Pharmacopœia of the United States; of this the dose is one fifteenth to one fourth of a grain, in pills, given every six, eight, or twelve hours.]

BALSAMUM PERUVIANUM. L.E.D.

(Myroxylon Peruiferum). _Peruvian Balsam._

QUALITIES. _Form_, a viscid liquid of a reddish brown colour. _Odour_, fragrant and aromatic. _Taste_, hot and bitter. CHEMICAL COMPOSITION. Resin, volatile oil, and benzoic acid; it is therefore a true _balsam:_ this term was formerly applied to every vegetable resin having a strong scent and the fluidity of treacle, and which was supposed to possess many medicinal virtues; it is now restricted to those resins which contain the benzoic acid in their composition, of which there are only three, viz. the Balsams of _Peru_, _Tolu_, and _Benzoin_. SOLUBILITY. Water when boiled upon it dissolves only a portion of benzoic acid; æther is its most complete solvent; alcohol dissolves it completely, but the quantity of this menstruum must be considerable. PROPERTIES, stimulant and tonic, on which account in certain chronic affections of the lungs, it has been found a serviceable expectorant; Sydenham gave it in Phthisis, but wherever any inflammatory action is to be apprehended Dr. Fothergill wisely cautions us against its use. FORMS OF EXHIBITION. Diffused in water by means of mucilage, or made into pills with any vegetable powder. DOSE, gr. v to ʒj. ADULTERATIONS. A mixture of resin and some volatile oil with benzoin, is often sold for Peruvian Balsam, and the fraud is not easily detected, and is probably of but little importance.

BALSAMUM TOLUTANUM. L.E.D.

(Toluifera Balsamum.) _Balsam of Tolu._

QUALITIES. _Form_, a thick tenacious liquid becoming concrete by age, in which state it is usually found in the shops. _Taste_, warm and sweetish. _Odour_, extremely fragrant, resembling that of lemons. CHEMICAL COMPOSITION. Volatile oil, resin, and benzoic acid. SOLUBILITY. It is soluble in alcohol, forming a tincture which is rendered milky by water, but no precipitate falls. When dissolved in the smallest quantity of a solution of potass, its odour is changed into one that resembles clove pink. MEDICINAL USES. It has been regarded as expectorant. In turning to the classification of expectorants, p. 102, it will be found to occupy a place in the second division of our first class, for it may be considered as capable of stimulating the pulmonary exhalants; whence its use in chronic coughs. FORMS OF EXHIBITION. It may be suspended in water by means of mucilage, or yolk of egg, but it is rarely employed except on account of its agreeable flavour;[424] its virtues are similar to those of the balsam of Peru. OFFICINAL PREP. _Tinct: Benzoin. comp:_ L.E.D. _Tinct: Toluiferi Balsam:_ E.D. _Syrup: Tolut:_ L.

BELLADONNÆ[425] FOLIA. L.E.D.

(Atropa Belladonna.) _Deadly Nightshade._

QUALITIES. The leaves are inodorous. _Taste_, slightly nauseous, sweetish, and sub-acrid; their peculiar properties are not lost by drying. CHEMICAL COMPOSITION. Vauquelin found that the leaves contained a substance analogous to albumen, salts with a base of potass, and a bitter principle on which its narcotic properties depended, and more lately the presence of an alkaline element has been detected, which has received the appellation of _Atropia_, the sulphate of which crystallizes very beautifully. SOLUBILITY. Water is the most powerful solvent of its active matter. USES. It is a powerful sedative and narcotic, both as an internal medicine and as an external application; in this latter form, it alleviates local pains very effectually, but is liable to affect the nervous system. The recent leaves powdered, and made into an ointment with an equal weight of lard will be found an efficient form for many purposes; rubbed over the penis it prevents priapism and relieves chordee more effectually than any application which has been proposed. FORMS OF EXHIBITION. Every part of the plant is poisonous, and the berries from their beautiful appearance have often tempted the unwary; the leaves however furnish the most convenient and powerful form of exhibition; externally, they may be used as a poultice, internally, one grain of the dry leaves powdered, and gradually increased to 10 or 12 grains, or the leaves may be infused in boiling water in the proportion of four grains to two fluid-ounces, which may be given as a dose. A little of this infusion dropped into the eye permanently dilates the pupil, for which intention it has been successfully applied previous to an operation for the cataract. The extract of this plant, since its active principle is fixed, ought to possess activity, but as it occurs in commerce it is found to be very uncertain and variable, a circumstance which entirely depends upon the manner in which it has been prepared.[426] See _Extractum Belladonnæ_. An overdose of belladonna produces the most distressing and alarming symptoms, and so paralyzing is its influence, that vomiting can be hardly excited by the strongest doses of tartarized antimony; in such cases vinegar will be found the best antidote, or the affusion of cold water over the surface of the body, after the application of which, emetics are more likely to perform their duty, for physiological reasons explained in p. 85. OFFICINAL PREPARATIONS. _Extract: Belladonnæ_ L. _Succus spissatus Atropæ Belladonnæ_. E.

BENZOINUM. L.E. Benzoe. D. (Styrax Benzoin)

vulgo, _Benjamin_.

QUALITIES. Form, brittle masses, composed of white and brownish, or yellowish fragments; _Odour_, fragrant; _Taste_, scarcely perceptible. When heated, it exhales benzoic acid in the form of crystals. CHEMICAL COMPOSITION. Resin, and a large proportion of benzoic acid. SOLUBILITY. It is readily dissolved by alcohol and æther, and is again separated from them by water; solutions of lime, and the fixed alkalies separate the benzoic acid from it, which can afterwards be recovered from such solutions by the addition of an acid. USES. It is considered expectorant, and was formerly used in asthma, and other pulmonary affections; it has however fallen into disuse, and is now principally employed in perfumery, and odoriferous fumigations.[427] OFFICINAL PREPARATIONS. _Acidum Benzoicum_ L.E.D. _Tinct: Benzoini comp:_[428] L.E.D. IMPURITIES. It is found in the market in various degrees of purity, the best is yellowish, studded with white spots: the worst is full of dross, and very dark or black.

BISMUTHI SUB-NITRAS L.

QUALITIES. _Form_, a white, inodorous, tasteless powder. CHEMICAL COMPOSITION. Oxide of Bismuth in combination with some water and a little nitric acid. SOLUBILITY. It is insoluble in water and dilute acids, but is dissolved by the concentrated acids, and is again precipitated by water. The alkalies, Potass and Soda, also dissolve it, but sparingly; it is more soluble in ammonia. USES. It was formerly employed as a cosmetic, under the name of _Magistery of Bismuth_, or that of _Pearl White_;[429] since, however, it becomes black from the operation of Sulphuretted Hydrogen and its compounds,[430] much inconvenience attends its application. Its medicinal powers appear to have been first noticed by Jacobi,[431] but the remedy attracted little or no attention until the publication of a paper upon the subject by Odier[432] of Geneva. The diseases in which its powers as a tonic have been more particularly displayed, are Gastrodynia, Pyrosis, and Dyspepsia attended with cholic. Dr. Marcet in a paper read in 1801 before the Medico-chirurgical Society of London, says, “I have had frequent opportunities of trying the oxide of Bismuth in spasmodic affections of the stomach in Guy’s Hospital, and those trials have fully confirmed the opinion which I formerly gave of the utility of this medicine.” The practitioner will receive a further confirmation of its value by referring to Dr. Bradsley’s Medical Reports: and Dr. Yeats has published in the Royal Institution Journal[433] a striking case illustrative of its efficacy.[434] Dose, gr. v to xv, in the form of pills.

BISTORTÆ RADIX. L.E.D.

(Polygonum Bistorta.) _Bistort Root._

QUALITIES. This root has no odour, but is highly astringent. CHEMICAL COMPOSITION. Its active principles are tannin and gallic acid. MED. USES. It acts as an astringent, and is accordingly used in hemorrhages and fluxes. DOSE of the root ℈j-ʒj; of a decoction f℥j-f℥ij. Combined with _Calamus_ it has been successfully administered for the cure of intermittent fevers. _See p. 167._

CALAMI RADIX. L. Acori Calami Radix. E.

Acorus. D. (Acorus Calamus). _Sweet Flag Root._

QUALITIES. This root is full of joints, crooked, and flattened on the sides, internally of a white colour, and loose spongy texture. _Odour_, fragrant and aromatic. _Taste_, bitter and pungent, qualities which are improved by exsiccation. CHEMICAL COMPOSITION. The principles in which its qualities reside appear to be essential oil, and bitter extractive; the root likewise contains fecula, which is copiously precipitated from its infusion by sub-acetate and acetate of lead. Watery infusion extracts all its virtues, but decoction impairs them. Spirit is also an appropriate solvent, and a resinous extract may be produced accordingly. USES. It is not employed so frequently as it deserves;[435] it would be a useful addition to many of the compound infusions of vegetable stomachics. DOSE. A cupful of the infusion made by adding ʒvj of the dried root to f℥xij of boiling water. It is so favourite a remedy with the native practitioners of India, in the bowel complaints of children, that there is a penalty incurred by any druggist who will not, in the middle of the night, open his door and sell it, if demanded.

CALUMBÆ RADIX. L. (_Cocculus Palmatus._)

Colomba, Radix. E.D. _Calumba Root._

QUALITIES. _Form_, the dried root imported into this country is in transverse sections; the bark is thick, and easily detached; the wood is spongy and yellowish; the pieces are frequently perforated, evidently by worms. _Odour_, slightly aromatic. _Taste_, bitter and somewhat acrid. CHEMICAL COMPOSITION. Cinchonia, bitter resin, volatile oil, and starch, in addition to which M. Planche has found a peculiar animal-like substance; it appears also to contain Malate and Sulphate of Lime. SOLUBILITY. Boiling water takes up about one-third of its weight, but proof spirit appears to be its most perfect menstruum. INCOMPATIBLE SUBSTANCES. No change is occasioned in the infusion by the solutions of nitrate of silver, sulphate of iron, muriate of mercury, or tartarized antimony; but precipitates are produced by the _infusion of galls, and yellow Cinchona bark_, by _sub-acetate and acetate of lead_, _oxy-muriate of mercury_, and _lime-water_. The infusion very soon spoils. DOSE of the powdered root gr. xv to ʒss; of the infusion f℥iss to f℥ij. USES. It is one of the most valuable tonics and stomachics which we possess. It seems to be superior to many others, from not possessing astringent, and stimulant powers, on which account it is singularly eligible in certain pulmonary and mesenteric affections; it may be given in combination with chalybeates, aromatics, saline purgatives, or with rhubarb, as circumstances may require. (_Form. 34, 155._) OFFICINAL PREPARATIONS. _Infus: Calumbæ_. L. _Tinct: Calumbæ_. L.E.D. It becomes worm-eaten by age, and, in that condition, should be rejected. Those pieces which have the brightest colour, and the greatest specific gravity, are the best. The root of _white briony_, tinged yellow with the tincture of Calumba, has been fraudulently substituted for this root.

CAMBOGIA. L. _Gamboge._ (_Stalagmitis Cambogioides._ ) Gambogia. E.D.

QUALITIES. _Form_, lumps of a solid consistence, breaking with a vitreous fracture; _Odour_, none; _Colour_, deep yellow, bordering on red, and becoming, when moistened, a brilliant light yellow. _Sp. Grav:_ 1·221. _Taste_, slightly acrid, but which is not experienced unless it be allowed to remain long in the mouth. CHEMICAL COMPOSITION. One part of gum, (_Cerasin_,) and four parts of a brittle resin; but this knowledge throws no light on the nature of its cathartic property. SOLUBILITY. When triturated with water two-thirds of its substance are speedily dissolved, and a turbid solution results; alcohol dissolves nine-tenths, and forms a yellow transparent tincture, which is rendered turbid by the addition of water; sulphuric ether dissolves six-tenths of the substance; it is also soluble in alkaline solutions, and the resulting compound is not rendered turbid by water, but is instantly decomposed by acids, and the precipitate so produced is of an extremely brilliant yellow colour, and soluble in an excess of acid. INCOMPATIBLE SUBSTANCES. No bodies appear to produce in gamboge such a chemical change as to destroy the chemical properties which distinguish it, but by a mechanical admixture, its solubility and consequently its operation, may be materially modified. Dr. Cullen found that the inconvenience arising from its too rapid solubility, and sudden impression upon the stomach, might be obviated by diminishing the dose, and repeating it at short intervals as directed in _Form: 89_. FORMS OF EXHIBITION. No form is more judicious than that of pill. Its alkaline solution has been sometimes exhibited in dropsy, when it is said to operate both on the bowels and kidneys. DOSE, gr. 2 to gr. 6. USES. It is a powerful drastic cathartic, and hydragogue, very liable to excite vomiting, and from this peculiar action upon the stomach it has been frequently employed with success in the expulsion of teniæ (_Form: 161_.) and it accordingly enters as an ingredient into many of the empirical compositions which are sold for the cure of tape worms.[436] OFFICINAL PREPARATIONS. _Pil: Cambogiæ comp:_ L. There is considerable difference in the degree of purity in which this substance occurs in the market; it should be estimated by its clearness and brilliancy.

CAMPHORA. L.E.D. (_Laurus Camphora._[437])

Camphor.

QUALITIES. _Form_, a white brittle substance, unctuous to the touch, but possessing at the same time a degree of ductility which prevents its being easily pulverised, unless a few drops of spirit be previously added. It is capable of affecting a crystalline form.[438] _Odour_, peculiar, fragrant, and penetrating. _Taste_, bitter, pungent, and aromatic. _Specific gravity_, ·9887, it therefore swims on water; it is so volatile that during warm weather a considerable proportion will evaporate, especially if at the same time the atmosphere be rather moist, for the reason stated in page 175. It is readily ignited, and burns with a brilliant flame and much smoke; it melts at 288°, and boils at 400. CHEMICAL COMPOSITION. It is a proximate vegetable principle, resembling the essential oils in many of its habitudes, and probably differs from them in composition only in containing a larger proportion of carbon. SOLUBILITY. Water may be said to dissolve about a nine hundredth part of its weight, or f℥j rather more than gr. ½, but its solvent power is considerably increased by the addition of carbonic acid gas; camphor is also rendered more soluble by trituration with magnesia; it is soluble in an equal weight of alcohol, but it is again separated by the addition of water; it is also dissolved by oils, both fixed and volatile,[439] especially if their temperature be a little raised, and by sulphuric and other æthers, but strong acetic acid may be said to be its most powerful solvent. By repeatedly distilling it with nitric acid it is converted into _Camphoric acid_, an acid distinguished by peculiar properties, and composing, with alkalies and earths, a class of salts called _Camphorates_, but which do not possess any medicinal value. The alkalies do not produce any effect upon camphor. INCOMPATIBLE SUBSTANCES. It is not affected by any substance with which we can combine it. FORMS OF EXHIBITION. It is preferable in the form of mixture, since it is very liable in the solid state to excite nausea, and, from swimming on the contents of the stomach, to occasion pain at its upper orifice. If a larger dose be required than that which water can dissolve, an additional proportion may be suspended by means of sugar, almonds, yelk of egg, or mucilage, for which purpose three times its weight of gum arabic is required. If Camphor be first dissolved by trituration in a very small portion of oil, it readily mixes with mucilage of gum arabic, and may then be conveniently blended with liquids. It has also the property of uniting with gum-resins, and of converting them into permanently soft, and uniform masses; hence they may sometimes be conveniently applied for diffusing it in water. It may be formed into pill-masses by stiff mucilage, fœtid gums, or by a confection. MEDICINAL USES. In moderate doses it exhilarates, without raising the pulse, and gives a tendency to diaphoresis; and under certain conditions of the body, when opium fails, it will frequently promote sleep. As its effects are transient, its dose should be repeated at short intervals. _Illustrative Formulæ_ 1, 6, 21, 125, 134, 164. Camphor is said to correct the bad effects of opium, mezereon, cantharides, and the drastic purgatives, and diuretics. DOSE, gr. ij to ℈j. In excessive doses it occasions anxiety, vomiting, syncope, and delirium; these violent effects are best counteracted by opium. OFFICINAL PREPARATIONS. _Mistura Camphoræ._ L.D. _Emulsio Camphorata._ E. _Spiritus Camphoræ_, L.E.D. _Tinctura Camphoræ comp:_ L.E.D. _Acidum Acetosum Camphoratum._ E.D. _Linimentum Camphoræ._ L.E.D. _Liniment: Camphoræ comp:_ L. _Liniment: Saponis_. (=G=) L.E.D. ADULTERATIONS. It has been stated that pure camphor may be known by placing it upon hot bread, when it will turn moist, whereas an adulterated specimen becomes dry—but with what can it be adulterated?

CANELLÆ CORTEX. L.E.D. Canella Bark, (_Canella Alba Cortex._)

_Wild Cinnamon._

QUALITIES. _Form_; it occurs in quilled and flat pieces; the former are of a whitish-yellow colour, considerably thicker than cinnamon; the latter, which are probably the bark of the larger branches, or of the stem of the tree, are yellow on the outside, and pale brown within. _Odour_, resembling that of cloves. _Taste_, warm, pungent, and slightly bitter. CHEMICAL COMPOSITION. Its virtues depend upon an essential oil, and a bitter resin. SOLUBILITY. Water extracts only the bitterness, but proof spirits both the bitterness and aroma. MEDICINAL USES. As a warm stimulant to the stomach, and as a corrigent to other medicines. In America it is considered as a powerful antiscorbutic. DOSE of the powdered bark gr. x to ʒss. Officinal Preparations. _Tinct. Gentian. comp._ (=B. G.=) E. _Vinum Aloes_, (=G=) L.D. _Pulv. Aloes cum canella_, (=G=) D.

CANTHARIDES.[440] (Cantharis Vesicatoria.)

_Blistering, or Spanish Flies._

This beautiful insect of the beetle tribe is exceedingly abundant in the southern parts of Europe, and particularly in Spain. They are collected from the leaves of the different trees on which they delight to dwell, in June and July, and are afterwards destroyed, as recommended by Dioscorides, by the fumes of strong vinegar, and dried in the sun. The chemical history of Cantharides is still involved in some obscurity; the blistering principle has been obtained by Robiquet in a separate state, when it assumes the form of small crystalline plates, having a micaceous lustre, not unlike spermaceti; Dr. Thomson has given to it the name of _Cantharidin_;[441] when pure, it is insoluble in water and in cold alcohol; boiling alcohol, however, dissolves it, but precipitates it again on being cooled. Æther and the oils dissolve it readily. Although not soluble in water it is rendered so by the presence of a yellow matter which exists in native combination with it. A very minute portion of this substance dissolved in sweet oil, and applied to the skin with a piece of paper, produces vesication in five or six hours. In addition to this active principle, Cantharides contain a green concrete oil; a yellow fluid oil; a peculiar black substance soluble in water and proof spirit, but not in pure alcohol; a saponaceous or yellow substance, soluble both in water and alcohol; Uric acid; Acetic acid; Phosphate of Magnesia, and a parenchymatous substance.[442] MEDICINAL USES. Cantharides, when administered internally, are powerfully stimulant and diuretic;[443] and whether applied as a vesicatory to the skin, or taken into the stomach, they have a peculiar tendency to act upon the urinary organs, and especially to irritate and inflame the neck of the bladder, and occasion strangury. On this account they have been very successfully employed both for the cure of incontinence of urine, and suppression of this discharge, from torpor or paralysis of the bladder; they have also been used in gleet and leucorrhæa, and in cases of seminal weakness and impotence. In consulting the works of Dioscorides, Galen, and Pliny, we shall find they entertained a notion, that the _virus_ existed only in the body of the fly, and that the head, feet and wings, contained its antidote! Hippocrates prescribed them internally in Dropsy, Jaundice, and Amenorrhœa; and yet in the end of the sixteenth century, Dr. Groenvelt was charged and sued[444] for giving them inwardly, in substance, for the cure of the stone. DOSE, in substance, not exceeding gr. i, combined with opium or hyoscyamus. See _Tinctura: Cantharid_. A strong decoction of the Cantharides in Oil of Turpentine furnishes a most powerful Epispastic, and may be easily applied by means of dossils of lint. As the general belief, which exists with respect to the aphrodisiac powers of this substance, may induce persons to try its efficacy in large doses, either for goading the exertions of exhausted nature, or for incensing the passions of females whose seduction is meditated, it behoves the medical practitioner to become acquainted with the symptoms which it may produce, and of which the following may be considered as the most prominent;—violent retching; copious alvine evacuations, frequently bloody; very severe colics; active inflammation of the stomach and intestines; sometimes universal convulsions, attended with a horror of liquids, resembling that which occurs in hydrophobia; furious delirium, &c. But the affections of the urinary passages, and organs of generation, may be regarded κατεξοχην, as the peculiar symptoms of poisoning by Cantharides; such as heat in the bladder, bloody micturition, horrible strangury, painful and obstinate priapism, _satyriasis_, &c. The method of treatment to be pursued on such occasions will consist in copious bleeding, warm bath, local fomentations, mild and mucilaginous drinks; and opium, especially in the form of clyster or suppository. OFFICINAL PREP. _Tinct: Cantharid:_ L. _Emplast: Cantharid:_ L. _Ceratum Cantharid:_ L. _Unguent: Infusi Cantharid: Vesicat:_ E. _Unguent: Cantharid:_ D. The flies do not lose their virtues by being kept; it is, however, curious that even those acrid insects are soon reduced to dust by others feeding upon them; but since the inert parenchymatous portion is alone selected by them, the residue is extremely active.[445]

CAPSICI BACCÆ. L.E.D. Berries of the Capsicum. (Capsicum Annum.)

QUALITIES. _Form_, pods, long, pointed, and pendulous; _Colour_, when ripe, a bright orange red. _Odour_, aromatic and pungent. _Taste_, extremely acrimonious and fiery. SOLUBILITY. Its qualities are partially extracted by water, but more completely by æther and spirit. CHEMICAL COMPOSITION. Cinchonia, resin, mucilage, and an acrid principle said to be alkaline.[446] INCOMPATIBLE SUBSTANCES. The infusions of capsicum are disturbed by _Infusion of Galls_; _Nitrate of Silver_; _Oxy-muriate of Mercury_; _Acetate of Lead_; _the Sulphates of Iron, Copper and Zinc_; _Ammonia, Carbonate of Potass, and Alum_, but not by sulphuric, nitric, or muriatic acid. MEDICINAL USES. It is a most powerful stimulant to the stomach, and is unaccompanied with any narcotic effect; as a gargle in cynanche maligna, and in relaxed states of the throat, it furnishes a valuable remedy; combined with purgatives, it proves serviceable in dyspepsia, (_Form: 78_,) it has lately been given with success in the advanced stages of acute rheumatism; in various diseases attended with cold feet, it has been recommended to wear socks dusted with Cayenne Pepper. FORMS OF EXHIBITION. It may be given, made into pills with crumb of bread, or in the form of tincture, diluted with water; for the purpose of a gargle, a simple infusion in the proportion of gr. j to f℥j of boiling water, or fʒvi of the tincture to f℥viij of the _Infusum Rosæ_, may be directed. DOSE, of the substance, gr. vj to x, of the tincture fʒj to fʒij in an aqueous vehicle. OFFICINAL PREPARATIONS. _Tinct: Capsici:_ L.D.[447]

_Cayenne Pepper_ is an indiscriminate mixture of the powder of the dried pods of several species of capsicum, but especially of the Capsicum _baccatum_, (Bird pepper.)

ADULTERATIONS. Cayenne pepper is generally mixed with _muriate of soda_, which disposes it to deliquesce. _Red Lead_ may be detected by digesting it in acetic acid, and adding to the solution sulphuret of ammonia, which will produce, if any lead be present, a dark coloured precipitate; or the fraud may be discovered by boiling some of the suspected pepper in vinegar, and after filtering the solution adding to it sulphate of soda, when a white precipitate will be formed, which, after being dried and exposed to heat, and mixed with a little charcoal, will yield a metallic globule of lead.

CARBO LIGNI. L.E.D. _Charcoal._

QUALITIES. It is a black, inodorous, insipid, brittle substance; when newly prepared it possesses the property of absorbing very considerable quantities of the different gases; it is also capable of destroying the smell and taste of a variety of vegetable and animal substances, especially of mucilages, oils, and of matter in which _extractive_ abounds; and some medicines are said to be even deprived of their characteristic odour by remaining in contact with it, as Valerian, Galbanum, Balsam of Peru, and Musk. The use of charring the interior of water casks, and of wrapping charcoal in cloths that have acquired a bad smell, depends upon this property; for the same reason it furnishes a very excellent tooth powder,[448] for which purpose, that which is obtained from the shell of the cocoa nut is to be preferred. None of the fluid menstrua with which we are acquainted have any action whatever as solvents upon carbon.[449] MEDICINAL USES. It is antiseptic, and has been administered internally, to correct the putrid eructations which sometimes attend dyspepsia, but in order to produce this effect it should be newly prepared, or such as has been preserved from the access of air, for it operates by absorbing the putrid gas, as well as by checking the decomposition of the undigested element.[450] DOSE, grs. x to ʒj. It has been lately asserted to possess powers as an antidote to arsenic; if this be true, its action can only be mechanical by absorbing like a sponge the arsenical solution, and thereby defending the coats of the stomach from its virulence.[451] Charcoal, when mixed with boiled bread, forms a very valuable poultice for foul and gangrenous sores. In a state of impalpable powder, it is said to be effectual as a styptic; Dr. Odier informs us that the celebrated _powder of Faynard_, for stopping hemorrhage, was nothing more than the charcoal of beech-wood finely powdered.

Charcoal is prepared for the purposes of medicine and the arts, from a variety of substances, viz.

BURNT SPONGE. _Spongia Usta._ L. Consists of charcoal with portions of phosphate and carbonate of lime, and sub-carbonate of soda; it has been highly commended in bronchocele and scrophulous complaints, in the form of an electuary, or in that of a lozenge, and it has been lately asserted that it owes its power to the presence of Iodine.

VEGETABLE ÆTHIOPS. _Pulvis Quercus marinæ._ From the _fucus vesiculosus_, or bladder-wrack, used as the preceding.

IVORY BLACK. _Ebur Ustum._ From ivory shavings burned; used as a dentifrice and a pigment, under the name of “_blue-black_,” for its hue is bluish; but bone-black is usually sold for it.

LAMP BLACK. _Fuligo Lampadum._ By burning resinous bodies, as the refuse of pitch, in furnaces of a peculiar construction.

WOOD SOOT. _Fuligo ligni_, collected from chimnies under which wood is burnt. It contains sulphate of ammonia, which imparts to it its characteristic bitterness. It has been considered antispasmodic, and a tincture was formerly prepared of it.

CARDAMOMI SEMINA. L.D. ( Matonia[452] Cardamomum.)

Amomum Repens. E. _Cardamom Seeds._

QUALITIES. _Odour_, aromatic and agreeable; _Taste_, warm and pungent, but unlike the peppers, they do not immoderately heat the stomach. SOLUBILITY. Water, alcohol and æther extract their virtues; the two latter most completely, and the result is transparent, whereas the watery infusion is turbid and mucilaginous. CHEMICAL COMPOSITION. Fecula, mucilage, and essential oil. MEDICINAL USES. They are carminative and stomachic, and prove grateful adjuncts to bitter infusions; they are principally employed to give warmth to other remedies. DOSE of the powder, gr. vj to ℈j. OFFICINAL PREPARATIONS. _Extract: Colocynth: comp:_ (=E=) L.D. _Tinct. Cardamomi_, L.E.D. _Tinct. Cardamom: comp:_ L.D. _Tinct: Cinnamomi, co._ (=B=) L.E. _Tinct. Gentian, co._ (=G=) L. _Tinct. Rhei_, (=E=) L.E.D. _Tinct. Rhei cum Aloe_, (=G=) E. _Tinct. Sennæ_, (=E=) L.D. _Spir. Ether. Aromat._ (=B=) L. _Vinum Aloes Socot._ (=G=) E. _Confect. Aromat._ (=B=) L. _Pulv. Cinnamom. co._ (=B=) L.E.D. _Pil. Scilliticæ_, (=E=) E. _Infus. Sennæ._ D. (=E=.)

Cardamom seeds should be kept within their husks, or their virtues will soon be considerably impaired; they are frequently mixed with _grains of paradise_, which are much hotter and more spicy, but less aromatic in their flavour.

CARICÆ FRUCTUS, L.D. Fici Caricæ Fructus, E.

_The preserved Fruit of the Fig._

QUALITIES of the dried fig are too well known to require description. The fig consists almost entirely of mucilage and sugar. USES. It has been already stated that the most ancient cataplasm on record was made of figs, (2 Kings, chap. xx. 7.) they are employed medicinally in many demulcent decoctions, as _Decoctum Hordei comp:_ L.D. They are gently aperient; it is curious to learn that they constituted the chief part of the food of the ancient Athletæ.

CARYOPHYLLI. L.

(Eugenia Caryophyllata. _The unopened flowers dried._)

Caryophilli Aromatici Germen, E.

Caryophilli aromat. Calyx, D. _Cloves._