VII. CHEMISTRY AND PHARMACY.

63. State in which Morphia exists in Opium.—In the 80th article of our Quarterly Summary for January, we stated that Mr. Robinet had announced the discovery of a new acid in opium, with which the morphia was combined; while the meconic acid was alleged to be united with soda. To the former salt, he gave the name of codeate of morphia. Mr. Robiquet, however, has shown, that the pretended codeate, is a muriate of morphia, formed by double decomposition between the muriate of soda, employed by Mr. Robinet in his analysis, and meconate of morphia. The same decomposition shows the source of the meconate of soda. We observe that Mr. Robinet admits his mistake.—Archives Générales de Medicine.

64. Peculiar principles of Narcotic Plants.—"Dr. Brandes of Sabzerflen, having been prevented by extreme illness, induced by investigating the peculiar principles of narcotic plants, from completing his inquiries, has announced the results of his labours in general terms. He states, that he has found a peculiar narcotic principle in all the narcotic plants; as belladonna, hyosciamus, conium, stramonium, chelidonium, digitalis, &c. The narcotic principles are readily soluble in alcohol, ether, acids, and water, and of a highly offensive odour. This odour is so great in the principle of conium, that it is almost impossible for an individual of an irritable habit, to remain in the room, where there is an etherial solution, containing only a few grains of it. The smell of such a solution is equal to the smell, arising from twenty or thirty pounds of the plants. It is also remarkable, that as this principle is neutralized by acid, the disagreeable odour disappears, or is greatly diminished; which so far agrees with the circumstance, that the plants themselves give little of their peculiar smell, because the narcotic principle is not in a free state. Dr. Brandes has promised to communicate the manner of obtaining the principles."—Lond. Med. Repository, Feb. 1826.

65. Relative quantities of Cinchonia and Quinia in the most esteemed Varieties of Peruvian Bark.—Mr. Bally asserts, that practitioners, from observation, have classed the Peruvian barks in the following order;—first, the gray loxa bark, (Cinchona Officinalis;) then the red bark (Cinchona Magnifolia of Ruiz and Pavon, or Oblongifolia of Mutis;) and lastly the yellow bark, or calisaya, (Cinchona Cordifolia of Mutis, or pubescens of Valli.) The Cinchona Officinalis furnishes much cinchonia, and little quinia; the Cinchona Magnifolia affords about equal quantities of the two salifiable principles, while the Cordifolia contain much quinia.

Mr. Bally, assuming it as proved, that cinchonia is the more powerful salifiable base of the two in a medical point of view, considers, therefore, that, in regard to the above barks, chemical analysis justifies the order of their relative value, which had been previously deduced from their medical employment.—Archives Generales de Medecine.

66. Sulphate of Quinia, extracted from the Cinchona Bark, exhausted by Decoction.—Mr. Julia-Fontenelle, from the sparing solubility of quinia and cinchonia, suspected that decoctions and aqueous extracts of Peruvian bark contained but little of those vegetable alkalies; whence it would follow, that the residuum, generally rejected as having no febrifuge power, would still contain the greater part of them. This suspicion has been in a great measure verified. The aqueous extract was found to contain but little cinchonia and quinia; while the residuum of decoctions, giving the mean results, furnished two-thirds of the sulphate of quinia, yielded by the same weight of cinchona not acted on by water.

As decoctions and aqueous extracts of bark are febrifuge, though containing inconsiderable quantities of quinia, and cinchonia, Mr. Julia-Fontenelle is led to believe, that these salifiable bases are not the only febrifuge principles in Peruvian bark, but that the extractive matter also possesses that property.

His results present a striking difference between alcoholic and aqueous extracts of bark; for while the former contain nearly the whole of the salifiable principles, the latter contain very little.—Revue Medicale.

67. Analysis of Rhubarb.—It is some time since Mr. Nani, an Italian chemist, announced the discovery of a crystallizable vegetable alkali in rhubarb. Mr. Caventou has repeated the experiments of Mr. N. and finds them, in many respects, inaccurate. Upon analysing the alcoholic extract of rhubarb, by the aid of alcohol and ether, employed separately and combined, Mr. C. obtained a fatty matter, containing a little odoriferous volatile oil, and a yellow colouring principle, capable of crystallization, and of being sublimed without decomposition, which may be called rhubarbin. He also detected in the alcoholic extract, a brown substance, insoluble in water when pure, but rendered soluble by combination with rhubarbin; when it forms a compound, constituting the eaphopicrite of some chemists, and the rhubarbin of Psaff.—Archives Generales.

Mr. George W. Carpenter, of this city, prepares the medicinal principle of rhubarb in combination with sulphuric acid, under the name of sulphate of rhubarb, by the following process:

"Boil, for half an hour, six pounds of coarsely powdered Chinese rhubarb in six gallons of water, acidulated with two and a half fluid ounces of sulphuric acid; strain the decoction, and submit the residue to a second ebullition in a like quantity of acidulated water; strain as before, and submit it again to a third ebullition. Unite the three decoctions, and add, by small portions, recently powdered pure lime, constantly stirring it to facilitate its action on the acid decoction. When the decoction becomes slightly alkaline, it deposites a red flocculent precipitate, and the fluid is changed from a yellow to a crimson colour. The precipitate is then to be separated by passing it through a linen cloth, and dried; after which, reduce it to powder, and digest in three gallons of alcohol, at thirty-six degrees, in a water bath, for several hours, at a moderate heat. Separate this solution from the calcareous precipitate, and distil off three-fourths of the alcohol. There then remains a strong solution of rhubarbine, to which add as much sulphuric acid as will exactly neutralize it. Evaporate this slowly to dryness, without having access to atmospheric air. The residuum will be of a brownish-red colour, intermingled with brilliant specks, possessing a slightly pungent styptic taste, soluble in water, and its odour that of the native rhubarb." This residuum is the sulphate of rhubarb. (Sulphate of rhubarbin.?)

Mr. Carpenter assures us, that this preparation contains the medicinal principle of the rhubarb, apart from its inert portion; and considers it as bearing the same relation to rhubarb, as the sulphate of quinia to the Peruvian bark. The Chinese rhubarb, at half the price, furnished twice as much rhubarbin as the reputed Russian, which Mr. C. considers to be spurious in the Philadelphia market, being the English prepared in imitation of the Russian.—Philadelphia Journal of the Medical & Physical Sciences. May, 1826.

68. Alkaline Lozenges of Bicarbonate of Soda.—Mr. D'Arcet proposes the following formula for these lozenges:—Take of

Bicarbonate of Soda, pure and dry, and in fine powder,5 parts.
Very white Sugar, in fine powder,95
Mucilage of Gum Tragacanth,q.s.
Essential oil of Mint, pure and fresh,2 or 3 drops
for about every 3 ounces of mixture of bicarbonate and sugar.

Shake the bicarbonate and sugar in a well dried bottle, with the view of mixing them intimately. Withdraw the mixture from the bottle, and add the mucilage and oil of mint, blending the whole together on a marble. The mass obtained, is then to be divided into lozenges, which should weigh, when dried, about 15 grains each. As they slightly attract moisture, they ought to be kept in a dry place, or in well stopped bottles.

Mr. D'Arcet praises very highly the effects of these lozenges in disordered digestion, and in preventing its occurrence, as well from experiments made on his own person, as from observations on others. He believes their operation to be purely chemical, consisting in the saturation of the morbid acid of the stomach, and, therefore, not likely to be lessened by habit. Their effects are much more prompt than magnesia, either pure or in the state of carbonate.

In the phosphatic diathesis, where the urine is disposed to be alkaline, it would seem that these lozenges would do harm. But, perhaps, we have this security against their use in these cases, that the stomach would not at the same time be troubled with acidity. Annales de Chimie et de Physique, Jan. 1826.

69. Presence of Mercury in Samples of medicinal Prussic Acid.—Mr. Regimbeau, apothecary at Montpellier, has detected this impurity in some prussic acid, prepared in Paris. Its presence was first suspected, from a portion of the acid, accidentally dropped, leaving a white stain on the copper dish of a balance. It is probable, that the impure acid, spoken of, had been made by passing sulphuretted hydrogen through a solution of cyanide of mercury, according to Vanquelin's process; and that an insufficiency of the decomposing gas had been employed.

May not this accidental impurity explain the occasional salivating effects of prussic acid.

70. Proposed Method for preparing Protoxide of Mercury by precipitation, for Medical Employment.—Mr. Thomas Evans has published some observations on this subject, and justly remarks, that the blue pill, mercurial ointment, and other mercurial preparations, are not uniform compounds, but contain variable proportions of the real protoxide, and uncombined mercury. Some blue pill, which had been carefully prepared by Mr. E. by the usual process of trituration, was found to contain on analysis 20 per cent. of unoxidized mercury; and the blue mass from Apothecaries' Hall, London, furnished about the same proportion.

As it is obviously a desideratum to procure preparations of protoxide of mercury of uniform strength, Mr. Evans has been led to seek a process, by which to obtain this oxide in a pure state. After repeated experiments, he has pitched upon the following formula: Dissolve four ounces of caustic hydrate of potassa in a pound of water, and to the clear solution, decanted from any impurities, add four ounces of calomel, and shake the mixture frequently. Pour off the liquid, and wash the precipitate formed with water, and then dry it at a gentle heat.

In regard to the medical efficacy of the protoxide obtained in this way, Mr. Evans reports the following to be the results obtained by Dr. Coates, at whose suggestion the article was prepared. As a substitute for calomel, it is more apt to vomit and purge, two grain doses operating several times. As an alterative, it was found incomparably more efficacious than the blue pill, being more certain and regular in its operation. Dr. C. thinks, that one-fourth of a grain of the precipitated protoxide, as prepared by Mr. Evans, is equal to three or four grains of the blue mass.—Journ. of the Philad. Col. of Pharm. May, 1826.

The method here proposed for obtaining the black oxide of mercury by Mr. Evans, was first suggested and put in practice by Mr. Phillips. See his "Experimental Examination of the last edition of the Pharmacopœia Londinensis, London, 1811," page 114. His words are, "When solution of potash is employed, the several inconveniences attendant upon the use of lime-water are avoided, and a blackish coloured protoxide is obtained without heating the solution. As potash is much more soluble than lime, it is scarcely necessary to employ one-tenth part of the quantity of water; this not only renders the process more convenient, but the quantity of air contained in the water being less, very little of the oxide, perhaps none of it, is converted into peroxide." See also the experiments, and observations of Mr. Donovan, on Mercurial Ointment, &c. published in the Medical Journals, several years ago.

71. Goulard's Extract of Lead. Mr. Daniel B. Smith proposes the following formula for obtaining Goulard's extract of uniform strength:

Acetate of lead, crystallized,15 ounces, troy.
Protoxide of lead,9 ounces, troy.
Distilled water,4 pints.

"Boil them together for fifteen minutes and filter. The filtered liquid will weigh about five and a quarter pounds, is transparent, colourless, and of the specific gravity of 1.267. (30° Baumé.)"

We conceive that Mr. Smith has erroneously denominated the sugar of lead, a binacetate. The best usage is to deem that the primary saline compound, which contains a single proportional of acid and base. Accordingly we call the saturated carbonate of potassa, a bicarbonate; and Dr. Thomson calls borax, a biborate of soda, on account of its containing two proportionals of acid to one of base, notwithstanding the alkaline qualities of this salt. Goulard's extract is, therefore, a sub-binacetate of lead, or according to Dr. Thomson's recently suggested nomenclature, a diacetate.—Ibid.