ease in the structure of the human body. This greatest pathologist of the nineteenth century acknowledged the fundamental character of Morgagni's contributions. They furnished a starting point for the progress of modern medicine. "The search for the sedes morbi has advanced from the organs to the tissues, and from the tissues to the cells."

It was Marie François Xavier Bichat who made pathology dependent on a study of the tissues. He was born in the village of Thoirette, France, November 11, 1771, and died at Paris July 22, 1802. His father was a doctor of medicine who had received his professional training at Montpellier. The son, Xavier Bichat, after a very thorough general education at Nantua and Lyons, began the systematic study of medicine in the latter city in 1791. The political conditions of the time stimulated among the doctors a special interest in surgery, and Bichat came under the influence of Antoine Petit, the chief surgeon of the Hôtel Dieu of Lyons. The Bichats were not Revolutionists, and, after the siege of Lyons in 1793, Xavier left that city. Before the end of the year he took refuge in Paris, and entered as a student the school of the famous Desault, hoping later to become an army-surgeon. He mingled quietly with the other students of medicine at the Hôtel Dieu of Paris. The fall of Robespierre in

July, 1794, brought to the young man a greater sense of security and a fortunate incident gained for him the friendship and consideration of his master Desault. It was customary in the school for the students to take turns in preparing résumés of the great surgeon's lectures. One day Desault spoke at length on fractures of the clavicle, giving a demonstration of the use of his bandage. When the time came for the résumé, the student who was to have given it was not present and Bichat offered to take his place. Desault's assistant, in whose presence the report was made, was deeply impressed by Bichat's clearness of thought and of expression. He told Desault of the incident, and the master, conscious of Bichat's extraordinary endowments, took the young man into his home and treated him as a familiar friend and disciple.

Henceforth Bichat seemed indefatigable. His only relaxation was change of work. He assisted Desault at the hospital, in his operations, in his private practice, his professional correspondence, his researches in surgery. When, toward the close of his life, Desault gave an extended course of lectures on the diseases of the bones, his tireless assistant prepared a careful statement of the teachings of the various authors from the time of Hippocrates concerning each question taken under consideration. At the same time Bichat continued to dissect. He

along with Corvisart and others founded the Société médicale d'émulation, before which he read a number of papers, including one on the synovial membrane and another dealing with the tissues in a more general way. After the sudden death of Desault, in 1795, Bichat edited the fourth volume of his master's "Journal de Chirurgie," compiled two volumes of extracts from the "Journal," and brought out the last volume of Desault's works.

In 1797 Bichat undertook to lecture on anatomy, emphasizing the mutual relation of structure and function, and verifying his views by the experimental study of animals. He followed the course on anatomy with one on surgery, but was forced to desist for a time by a severe attack of hæmoptysis. On his recovery he gave a more extended course on anatomy, establishing a dissecting room and directing the work of about eighty students. In 1800 appeared two works setting forth Bichat's characteristic views concerning structure and function "Traité des membranes," and "Recherches physiologiques sur la vie et la mort." The former became the basis of Bichat's "Anatomie générale" (1801), which established his claim as the founder of histology; the latter distinguished between the vie animale and the vie organique. These correspond to the functions which have to do with the external adjustments of the organism on the one hand and to