Pharmacologia / by J.A. Paris.

Date:
1825
Catalogue details

Licence: Public Domain Mark

Credit: Pharmacologia / by J.A. Paris. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

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    of interesting and important examples, in illustration of this division of our subject; if we require a striking example of the agency of chemical combination in de- stroying the identity of the original constituents, and of giving origin to a compound of new powers, it may be exemplified by the well known instance of Sulphate of Potass, a substance possessing but a weak affinity for water, and exerting but little energy upon the ani- mal ceconomy; whereas the two ingredients of which it consists are distinguished for the extreme eagerness with which they unite with water, and for the caustic activity which they display in their action upon animal matter. Under this head the class of metals will also present itself to our consideration, all the individuals of which, with the exception perhaps of iron, are perfectly inert and harmless ; even arsenic, lead, copper, and mercury, which in certain states of combination constitute some of the most virulent of known substances, exert no action upon the living system, unless they be in union with some other body ; but when so united, how valu- able do they become, and what various medicinal effects may they not be made to produce. The Acetic Acid and Ammonia become neutralized by combination with each other, affording a compound of new virtues. Sulphate of Zinc, and Acetate of Lead, when mixed together in solution, decompose each other, and the Acetate of Zinc which is formed, affords a more valuable remedy than either of the for- mer salts, as an application in ophthalmia. The “ Mis- tura Ferri Composita ” of our Pharmacopoeia offers another example of the same chemical resource. I also beg; the reader to refer to the construction of Formula 82, which presents an instance of a purgative draught being produced by combination, in which the original