A BRIEF RETROSPECT OF THE EIGHTEENTH CENTURY. SECTION V. MATERIA MEDICA. THE knowledge of the nomenclature, the metho dical arrangement, and especially of the virtues of those substances which are employed either for nutriment or the cure of diseases, must be considered as forming a very important branch of medicine. Accordingly it has received much of the attention of physicians in all ages. But in no period of equal length have inquiries on this subject been pursued with so much accuracy and success, or the discoveries and improvements been so numerous, as during the century under review. Many new articles, in this period, have been added to the former catalogues; the properties of articles formerly known and employed have become better understood than before; the application of old remedies greatly extended; and the whole subject made to wear a more scientific aspect. From the account which has been already given of the state of the other branches of medicine, at the close of the seventeenth century, the reader will readily perceive that materia medica, so closely connected with them in its principles and application, must have been, at the same period, in a corresponding situation; perhaps it may even be said to have been less cultivated at that time than any other. branch of medical science. But soon after the commencement of the eighteenth century the views of medical philosophers began to be much more correct and enlarged on this, as well as many other subjects belonging to the healing art. About that time the cardinal qualities, and other jargon of the Galenists; the distilled waters, essences, quintessences, and extracts, of the chemists; and many of the wild opinions respecting the application and efficacy of remedies, which resulted from mathematical and mechanical doctrines, began to decline; while new light, from various quarters, directed to more rational methods of experimenting and philosophising on the subject. The improvements which were made in the science of Botany, in the course of the last age, proved the source of many important additions to the materia medica. New plants of great medicinal value were brought from every part of the globe. Vegetables were examined, and their properties ascertained by means of more numerous, patient, and enlightened experiments than preceding naturalists had attempted. The service rendered particularly to |