Fig. 57.—Ludwig, 1816-1895.
Ludwig.—Among the men who handed on the torch of Müller there has already been mentioned Ludwig (Fig. 57). For many years he lectured in the University of Leipsic, attracting to that university high-minded, eager, and gifted young men, who received from this great luminary of physiology by expression what he himself had derived from contact with Müller. There are to-day distributed through the universities a number of young physiologists who stand only one generation removed from Johannes Müller, and who still labor in the spirit that was introduced into this department of study by that great master.
Fig. 58.—Du Bois-Reymond, 1818-1896.
Du Bois-Reymond.—Du Bois-Reymond (Fig. 58), another of his distinguished pupils, came to occupy the chair which Müller himself had filled in the University of Berlin, and during the period of his vigor was in physiology one of the lights of the world. It is no uncommon thing to find recently published physiologies dedicated either to the memory of Johannes Müller, as in the case of that remarkable General Physiology by Verworn; or to Ludwig, or to Du Bois-Reymond, who were in part his intellectual product. From this disposition among physiologists to do homage to Müller, we are able to estimate somewhat more closely the tremendous reach of his influence.
Bernard.—When Müller was twelve years old there was born in Saint-Julien, department of the Rhône, Claude Bernard, who attained an eminence as a physiologist, of which the French nation are justly proud. Although he was little thought of as a student, nevertheless after he came under the influence of Magendie, at the age of twenty-six, he developed rapidly and showed his true metal. He exhibited great manual dexterity in performing experiments, and also a luminous quality of mind in interpreting his observations. One of his greatest achievements in physiology was the discovery of the formation within the liver of glycogen, a substance chemically related to sugar. Later he discovered the system of vaso-motor nerves that control and regulate the caliber of the blood-vessels. Both of these discoveries assisted materially in understanding the wonderful changes that are going on within the human body. But besides his technical researches, any special consideration of which lies quite beyond the purpose of this book, he published in 1878-1879 a work upon the phenomena of life in animals and vegetables, a work that had general influence in extending the knowledge of vital activities. I refer to his now classic Leçons sur les Phénomènes de la vie communs aux animaux et aux végétaux.
The thoughtful face of Bernard is shown in his portrait, Fig. 59. He was one of those retiring, silent men whose natures are difficult to fathom, and who are so frequently misunderstood. A domestic infelicity, that led to the separation of himself from his family, added to his isolation and loneliness. When touched by the social spirit he charmed people by his personality. He was admired by the Emperor Napoleon Third, through whose influence Bernard acquired two fine laboratories. In 1868 he was elected to the French Academy, and became thereby one of the "Forty Immortals."
