Page:Popular Science Monthly Volume 84.djvu/574

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570
THE POPULAR SCIENCE MONTHLY

especially popular. Cuvier, a morphologist and an ardent vitalist, was supreme and depreciated any attempt to explain or solve physiological problems by physico-chemical means. Bichat, though long dead, was very powerful and his explanations which were finally to overthrow the vitalistic conception had been misunderstood and misapplied to overemphasize it. Many scientists of the time asserted that living organisms could not be subject to exact experimentation.

Magendie was the foremost physiologist in France and believed in a modified vitalism. While he paid his respects to vitalism by admitting that some of the phenomena of life were beyond the scope of experimental investigation, he realized that physico-chemical explanations could solve many problems of physiology. Disgusted with the empty discussions of the vitalists, he went to the other extreme and threw his energies entirely into experimental study without thought or plan, and though his accomplishments were many, they fell far short, considering the time spent and energy consumed.

Bernard saw the fallacies of each line of endeavor and, at the outset strove to use all his powers of theoretical and practical reasoning, together with careful manipulation and observation. Besides his work at the college, he gave a course of private lectures and spent the remainder of his time at research, usually in some temporarily improvised private laboratory or in the chemical laboratory of some one of his friends. There was no room for his private research at the Collège de France.

In May, 1843, he published his first communication: "Recherches anatomiques et physiologiques sur la corde du tympan, pour servir à l'histoire de l'hemiplégie faciale," followed in the same year by his doctor's thesis—" Du suc gastrique et du son rôle dans la nutrition." The work on the chorda tympani nerve, suggested by Magendie's work on nerves, started a long series of similar studies. This was typical of his analytical and logical reasoning. He proceeded, step by step, in his experiments to their logical conclusion or until an observation suggested a separate line of inquiry which seemed to be more fruitful. His thesis on the gastric juice was also the first of a series which led to his great discovery of glycogen and the glycogenic function of the liver. The main result of this thesis was that cane sugar, injected into the blood, was excreted unchanged; but sugar which had previously been acted upon by gastric juice was not excreted when injected, but was retained and used by the tissues. These two pieces of work illustrate Bernard's line of thought. He was always interested in the action of the nervous system on the chemical changes involved in nutrition and worked from both the physiological and chemical aspect of the problem whenever possible.

In studying the difference in the digestion and nutrition between carnivora and herbivora, he noticed that fat fed to rabbits was digested