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Rh the development of pathology, but we may leave it for the moment to trace one other line of advance made by the physiologist; an advance in that phase of the subject which Du Bois Reymond characterized, in 1880, as "vivisection and zoochemistry" in contrast to the electrophysiology of nerve and muscle with which his own name is so closely linked, and in contrast also to the phase of physiology in which histology, following the lead of Schwann, was playing so large a part. This third field in physiology necessitates a shift of scene to France and Claude Bernard and his school and the study of the functions of organs and their secretions.

Claude Bernard (1813-1878) was the pupil and successor of Magendie. Magendie did many things, but best of all he made "the experimental method the corner stone of normal and pathological physiology and pharmacology." (Welch.) By this method he demonstrated, as Charles Bell had divined, the essentially different functions of the anterior and posterior roots of spinal nerves. Also he founded a journal of experimental physiology.

Bernard, departing widely from Magendie's work, followed in his researches one main idea, the action of the nervous system on the chemical changes which constitute the basis of nutrition and this problem he attempted to solve by either direct experimental investigation of nerves, or by chemical researches or by a combination of both methods. His most important discoveries were the demonstration (1) of the significance of the pancreatic juice in digestion; (2) the glycogenic function of the liver and (3) the vasomotor system. These investigations (1850-1860) with those of Ludwig (1851) on the mechanism of the secretion of the glands, with the earlier observation on gastric digestion made by our own countryman, William Beaumont (1833), and the discovery of pepsin by Schwann (1835) represent the principles out of which our present conception of the physiology of digestion has developed. Not only did Bernard make discoveries and work out the lines of progress for the study of the outward or external secretions of glands, but as a result of his study of the influence of the liver on carbohydrate metabolism, he formulated the theory of "internal secretions," which represents a field of physiology cultivated in the past few years with the greatest success and still full of promise for the future.

Bernard has the distinction of being the first man of science to whom France accorded a public funeral, a recognition not alone of personal worth, but also of the nation's debt to science and to research in the field of medicine.

Thus far I have presented the beginnings of those branches of medicine which deal with normal structure and function. Next in order of development comes that science which is concerned with the study of disease, pathology and upon which are based sound diagnosis and