The American dispensatory : containing the natural, chemical, pharmaceutical and medical history of the different substances employed in medicine, together with the operations of pharmacy / illustrated and explained, according to the principles of modern chemistry.

  • Coxe, John Redman, 1773-1864.
Date:
1827
Catalogue details

Licence: Public Domain Mark

Credit: The American dispensatory : containing the natural, chemical, pharmaceutical and medical history of the different substances employed in medicine, together with the operations of pharmacy / illustrated and explained, according to the principles of modern chemistry. Source: Wellcome Collection.

Provider: This material has been provided by the Harvey Cushing/John Hay Whitney Medical Library at Yale University, through the Medical Heritage Library. The original may be consulted at the Harvey Cushing/John Hay Whitney Medical Library at Yale University.

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    sediment; and it forms a limpid colourless solution with ammonia- The common distilled vinegar of the shops Varies essentially iu strength as well as purity; its acid powers differing from thirty to forty per cent, in value: and it is sometimes 7°, at others less than 5° by the revenue acetometer; and hence the difficulty of procuring an uniform article for medical application. This diffi- culty seems now obviated, as the pyrolignous acid mav be procured of any degree of concentration, from 6° of the acetometer, or 3.898 per cent, of real acetic acid, to 130°. or 63.09 per cent, of acid: and even higher, if required: the common or proof acid about equals in strength that of the best malt vinegar. 100 parts of which, will satu- rate H; pans oi crystallized sub-carbonat o( soda: and consequently contains somewhat less than five per cent. o\' real acid, requiring at least one-half part of water to reduce it to the strength of the best common distilled vinegar. It is found that acetic acid of forty-five per cent, real acid, dissolves camphor and the essential oils very readily. The British Colleges employ this distilled acid for most of the preparations in which the acetum purification of the American Pharmacopoeia is ordered. Indeed, as to any use made of it in that work, it might have been altogether omitted. ACIDUM ACETICUM. D. Acetic Acid. Acidum Ackticum FosTE. E. Strong Acetic J3 Concentrated Acetic Acid. Eadiced Vinegar. Syn. Acide Acetique, (F.) Essigsaure, (G.) Acido Acetico, (I.) Take ofsulphat of iron dried, one pound: acctat of lead, ten ounces.— Rub them together, put them into a retort^and distil in a sand bath, ivith a moderate heat as long as any Wcid comes over. E. This is one of the easiest processes for the purpose. Many others have been proposed, all of which are reducible to three classes, viz.. 1. Decomposing metalline acetats by heat, as verdigris. 2. Decomposing acetats by sulphuric acid, as in the Dublin for- mula, viz.. acetat of potash and sulphuric acid. 3. Decomposing acetats by means of suljmats: as in the formula above introduced from the Edinburgh College. The difference of the three classes is at once perceived. In the first case, the affinity oi the metallic oxyd for the acid is broken up bv the agency of heat: but the degree necessary is so great, that a part of the acid itself is generally decomposed, and the product has an unpleasant empyreumatic smell. Iu the second case, the acetic acid is driven from the base it was united with by the superior affi- nitv of the sulphuric acid. A part of the sulphuric acid, if great care be not taken, is decomposed, and sulphurous acid passes over * The acetometer was invented by Messrs. Taylors for this particular pur- pose. The principle consists in hrst forming' a neutral salt with dry hydrat of lime and the acid to be examined, and then taking1 the specific gravity of the solution.