First came his treatise on the membranes (_Traité des Membranes_); followed quickly by his Physiological Researches into the Phenomena of Life and Death (_Recherches Physiologiques sur la Vie et la Mort_); then appeared his General Anatomy (_Anatomie Générale_) in 1801, and his treatise upon Descriptive Anatomy, upon which he was working at the time of his death. His death occurred in 1801, and was due partly to an accident. He slipped upon the stairs of the dissecting-room, and his fall was followed by gastric derangement, from which he died. Results of His Work.--The new science of the anatomy of the tissues which he founded is now known as histology, and the general anatomy, as he called it, has now become the study of minute anatomy of the tissues. Bichat studied the membranes or tissues very profoundly, but he did not employ the microscope and make sketches of their cellular construction. The result of his work was to set the world studying the minute structure of the tissues, a consequence of which led to the modern study of histology. Since this science was constructed directly upon his foundation, it is proper to recognize him as the founder of histology. Carpenter says of him: "Altogether Bichat left an impress upon the science of life, the depth of which can scarcely be overrated; and this not so much by the facts which he collected and generalized, as by the method of inquiry which he developed, and by the systematic form which he gave to the study of general anatomy in its relations both to physiology and pathology." Bichat's More Notable Successors.--His influence extended far, and after the establishment of the cell-theory took on a new phase. Microscopic study of the tissues has now become a separate division of the science of anatomy, and engages the attention of a very large number of workers. While the men who built upon Bichat's foundation are numerous, we shall select for especial mention only a few of the more notable, as Schwann, Koelliker, Schultze, Virchow, Leydig, and Ramon y Cajal, whose researches stand in the direct line of development of the ideas promulgated by Bichat. Schwann.--Schwann's cell-theory was the result of close attention to the microscopic structure of the tissues of animals. It was an extension of the knowledge of the tissues which Bichat distinguished and so thoroughly investigated from other points of view. The cell-theory, which took rise in 1839, was itself epoch-making, and the science of general anatomy was influenced by it as deeply as was the science of embryology. The leading founder of this theory was Theodor Schwann, whose portrait is shown on page 245, where there is also a more extended account of his labors in connection with the cell-theory. Had not the life of Bichat been cut off in his early manhood, he might well have lived to see this great discovery added to his own.