Excerpt from Royle's Manual of Materia Medica and Therapeutics: Including the Preparations of the British Pharmacopoeia and Other Approved MedicinesThe materia medica is a choice repertory of the most precious gifts of nature and of science, and, as such, its individual Objects are intrinsically interesting. The three kingdoms of nature are fully represented. Chemistry is the presiding genius, and is attended by Mineralogy, Botany, and Zoology, and we are incidentally introduced to some of the most interesting operations of animals and plants.But it is necessary to know these objects, not only for their own sake, but to detect the impurities which they acquire by association, and the adulterations which are imposed by dishonesty. In the present day it would be folly to shut one's eyes to the fact, that we may have been watching day after day, and week after week, for the effects of a given medicine which we have prescribed, and at a loss to account for their absence, and at the end of this time discover, if we have the ability to do so, that the active principle is wanting. Severe competition between wholesale druggists, and the absence of an authorised and unexpected inspection of the drugs kept by both wholesale and retail druggists, render the precautions given under characters and tests in the Pharmacopoeia absolutely necessary and if a medical practitioner should be incapable of ascertaining the purity of the drugs he prescribes, he will, unless he send his patient to a reliable source, soon begin to lose faith in his prescriptions.About the PublisherForgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.comThis book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully, any imperfections that remain are intentionally left to preserve the state of such historical works.