1911 Encyclopædia Britannica/Du Bois-Reymond, Emil
DU BOIS-REYMOND, EMIL (1818-1896), German physiologist, was born in Berlin on the 7th of November 1818. The Prussian capital was the place both of his birth and of his life’s work, and he will always be counted among Germany’s great scientific men; yet he was not of German blood. His father belonged to Neuchâtel, his mother was of Huguenot descent, and he spoke of himself as “being of pure Celtic blood.” Educated first at the French college in Berlin, then at Neuchâtel, whither his father had returned, he entered in 1836 the university of Berlin. He seems to have been uncertain at first as to the bent of his studies, for he sat at the feet of the great ecclesiastical historian August Neander, and dallied with geology; but eventually he threw himself into the study of medicine, with such zeal and success as to attract the notice of the great teacher of anatomy and physiology, who was then making Berlin famous as a school for the sciences ancillary to medicine. Johannes Müller may be regarded as the central figure in the history of modern physiology. the physiology of the 19th century. Müller's earlier studies had been distinctly physiological; but his inclination, no less than his position as professor of anatomy as well as of physiology in the university of Berlin, led him later on into wide studies of comparative anatomy, and these, aided by the natural bent of his mind towards problems of general philosophy, gave his views of physiology a breadth and a depth which profoundly influenced the progress of that science in his day. He had, about the time when the young Du Bois-Reymond came to his lectures, published his great Elements of Physiology, the dominant note of which may be said to be this:—"Though there appears to be something in the phenomena of living beings which cannot be explained by ordinary mechanical, physical or chemical laws, much may be so explained, and we may without fear push these explanations as far as we can, so long as we keep to the solid ground of observation and experiment." Müller recognized in the Neuchâtel lad a mind fitted to carry on physical researches into the phenomena of living things in a legitimate way. He made him in 1840 his assistant in physiology, and as a starting-point for an inquiry put into his hands the essay which the Italian, Carlo Matteucci, had just published on the electric phenomena of animals. This determined the work of Du Bois-Reymond's life. He chose as the subject of his graduation thesis "Electric Fishes," and so commenced a long series of investigations on animal electricity, by which he enriched science and made for himself a name. The results of these inquiries were made known partly in papers communicated to scientific journals, but also and chiefly in his work Researches on Animal Electricity, the first part of which appeared in 1848, the last in 1884.
This great work may be regarded under two aspects. On the one hand, it is a record of the exact determination and approximative analysis of the electric phenomena presented by living beings. Viewed from this standpoint, it represents a remarkable advance of our knowledge. Du Bois-Reymond, beginning with the imperfect observations of Matteucci, built up, it may be said, this branch of science. He did so by inventing or improving methods, by devising new instruments of observation or by adapting old ones. The debt which science owes to him on this score is a large one indeed. On the other hand, the volumes in question contain an exposition of a theory. In them Du Bois-Reymond put forward a general conception by the help of which he strove to explain the phenomena which he had observed. He developed the view that a living tissue, such as muscle, might be regarded as composed of a number of electric molecules, of molecules having certain electric properties, and that the electric behaviour of the muscle as a whole in varying circumstances was the outcome of the behaviour of these native electric molecules. It may perhaps be said that this theory has not stood the test of time so well as have Du Bois-Reymond's other more simple deductions from observed facts. It was early attacked by Ludimar Hermann, who maintained that a living untouched tissue, such as a muscle, is not the subject of electric currents so long as it is at rest, is isoelectric in substance, and therefore need not be supposed to be made up of electric molecules, all the electric phenomena which it manifests being due to internal molecular changes associated with activity or injury. Although most subsequent observers have ranged themselves on Hermann's side, it must nevertheless be admitted that Du Bois-Reymond's theory was of great value if only as a working hypothesis, and that as such it greatly helped in the advance of science.
Du Bois-Reymond's work lay chiefly in the direction of animal electricity, yet he carried his inquiries—such as could be studied by physical methods—into other parts of physiology, more especially into the phenomena of diffusion, though he published little or nothing concerning the results at which he arrived. For many years, too, he exerted a great influence as a teacher. In 1858, upon the death of Johannes Müller, the chair of anatomy and physiology, which that great man had held, was divided into a chair of human and comparative anatomy, which was given to K. B. Reichert (1811-1883), and a chair of physiology, which naturally fell to Du Bois-Reymond. This he held to his death, carrying out his researches for many years under unfavourable conditions of inadequate accommodation. In 1877, through his influence, the government provided the university with a proper physiological laboratory. In 1851 he was admitted into the Academy of Sciences of Berlin, and in 1867 became its perpetual secretary. For many years he and his friend H. von Helmholtz, who like him had been a pupil of Johannes Müller, were prominent men in the German capital. Acceptable at court, they both used their position and their influence for the advancement of science. Both, from time to time as opportunity offered, stepped out of the narrow limits of the professorial chair and gave the world their thoughts concerning things on which they could not well dwell in the lecture room. Du Bois-Reymond, as has been said, had in his earlier years wandered into fields other than those of physiology and medicine, and in his later years he went back to some of these. His occasional discourses, dealing with general topics and various problems of philosophy, show that to the end he possessed the historic spirit which had led him as a lad to listen to Neander; they are marked not only by a charm of style, but by a breadth of view such as might be expected from Johannes Müller's pupil and friend. He died in the city of his birth and adoption on the 26th of November 1896. (M. F.)