16. In the second century of the Christian era, Galen, a Greek physician from Pergamus, and a disciple of the Alexandrian school, settled in Rome. He was learned in all branches of medicine, and wrote more copiously on the subject generally, than any other person amongst the ancients. For 1300 years, his opinions were received as oracular, wherever medicine was cultivated.
17. After the destruction of the Western empire by the barbarous nations, the science of medicine was cultivated only in the Greek empire, and chiefly at Alexandria, until it began to arrest the attention of the Arabians, in the seventh century. The works of several Greek philosophers and physicians were translated into Arabic, under the patronage of the caliphs, several of whom were zealous promoters of learning.
18. In the eighth century, the Caliph Almansur established, at Bagdad, a hospital for the sick, and an academy, in which, among other branches of knowledge, was taught the medical art. But it was in Spain, that Arabian learning rose to the highest point, and produced the most successful results. The University of Cordova became the most celebrated in the world, and continued to maintain its reputation for a long series of years. Arabian medicine reached its greatest eminence, in the eleventh century, under Avicenna.
19. In the tenth century, this science began to be taught in the schools of other parts of Europe; but its professors derived their knowledge of the subject from the Arabian school, or from Arabic translations of the ancient authors; and this continued to be the case, until the conquest of Constantinople by the Turks, in 1453. At this time, many erudite Greeks fled into Italy, and carried with them the ancient writings.
20. Before the general revival of this science in Europe, the cure of diseases was chiefly confided, in the western nations, to the priests and monks, who, however, generally relied more upon religious ceremonies, and the influence of sacred relics, than upon the application of medical remedies. The superstitions of those barbarous times, respecting the means of curing diseases, have not yet entirely disappeared, even from the most enlightened nations of Christendom.
21. The science of chemistry began to attract much attention about the beginning of the sixteenth century; and the many powerful medical agents which it supplied, at length produced a great change in the theory and practice of medicine. Many valuable medicines of the vegetable kind, were also obtained from America. The discovery of the circulation of the blood by William Harvey, in 1620, imparted a new impulse to medicine; but, like chemistry, it gave rise to many absurd and hurtful theories.
22. Researches in different branches of medicine were continued with ardor in the seventeenth century, in various parts of Europe; and numerous discoveries of importance were made, especially in anatomy. Many theories regarding the origin of diseases, and their treatment, were proposed, advocated, and controverted; but all these were overthrown by Stahl, Boerhaave, and Hoffman, three eminent theorists, in the early part of the eighteenth century.
23. These distinguished men were followed by others of equal celebrity, in the same century, who, in part at least, exploded the doctrines of their predecessors. The present century, above all other periods, is remarkable for men eminent in this profession; and, although all do not exactly agree in opinion, yet, guided in their conclusions by a careful observation of facts, they are less under the influence of visionary theories than physicians of former times. Besides, many of the subjects of former controversy having been satisfactorily settled, there are now fewer causes of division and excitement among the medical profession.
24. Medical science comprises several branches, of which the following are the principal; viz., Anatomy, Surgery, Materia Medica, Chemistry, the Theory and Practice of Physic. On these subjects, lectures are given in several colleges and universities in Europe, and in the United States. In this country, an attendance on two regular courses of lectures entitles the student to the degree of Doctor of Medicine, provided he can sustain with sufficient ability, an examination before the professors, or, as they are usually termed, the medical faculty.
25. The degree of M. D. conferred by a college or university, is a passport to practice, in every state of the Union; and, in some states, none are permitted to attend the sick, professionally, without having first obtained a diploma conferring such degree. In other states, however, no legal restrictions are imposed on the practitioners of the healing art; or, they are licensed by a board of physicians, constituted by law for the purpose.