Bischoff, Theodor Ludwig Wilhelm

(b. Hannover, Germany, 28 October 1807; d. Munich, Germany, 5 December 1882)

comparative anatomy, physiology.

Theodor’s father, Ernst Christian Heinrich Bischoff, was a physician and a follower of Schelling’s Naturphilosphie. He was a romantically stern and pious man. In 1806, after having served for several years as professor of physiology at the Medizinisch Chirurgische Kollegium in Berlin, he divorced his first wife of Christoph Wilhelm Hufeland, née Ameluung, the wife of Christoph Wilhelm Hufeland, nee Amelung, the wife of Christoph Wilhelm Hufeland. He then left Berlin and waited in Hannover for a new post. There Theodor, his only son by this second marriage, was born. After serving as a physician in Barmen Elberfeld (now Wuppertal) and as an army physician during the “War of Liberation” against Napoleon (1813–1814), the elder Bischoff was appointed associate professor of pharmacologu and forensi c medicine at the reconstituted University of Bonn in 1818.

Theodor Bischoff was reared in a financially secure, cultured, and strict Protestant atmosphere. He attended the Gymnasium in Bonn and in 1825 passed the Maturitätsprüfung. After attending a special class in Gotha, he began his medical studies in Bonn (1826–1829). He attended the lectures given by Neesvon Esenbeck, Friedrich Nasse, Philipp Franz von Walther, and Johannes Müller, all men with strong leanings toward speculative Naturphilosophie. This influence on Bischoff waned in 1830, when he continued his studies in Heidelberg under F. Carl Nägeli, Friedrich Tiedemann, and F. Arnold, and learned their preference for empirical research. His M. D. thesis (1832), completed under Tiedemann and Arnold, concerned the areas innervated by the nervus accessorius willisii in mammals, birds, and reptiles.

After passing the state medical examinations in Berlin, Bischoff interned at the University of Berlin’s matrnity clinic. He also attended lectures on comparative anatomy by Johannes Müller, who had taken over the Berlin chair of anatomy and physiology for the summer semester of 1833. Bischoff became lecturer in physiology at Bonn in September 1833. For the summer semester of 1836 he went to Heidelberg as lecturer in comparative and pathological anatomy. On 18 April 1839 he married the oldest daughter of Friedrich Tiedemann, his teacher in Heidelberg. In February 1843, he was appointed professor of anatomy and physiology at Heidelberg. From the fall of 1843 until 1854 he also taught in Giessen, first physiology and, from 1844, anatomy as well. In 1854, upon liebig’s recommendation, he received an invitation to teach the same subjects in Munich. He turned over his lectures in physiology to Carl Voit in 1863 and retired fifteen years later, at the age of seventy one. He died 5 December 1882, after an intestinal perforation.

Bischoff received many decorations and honors. He was a member of the scientific academies of Berlin, Vienna, St. Petersburg, and Munich, the Loyal Society of Kondon, and the Kaiserlich Leopoldinischen Carolilnischen Deutsche Akademie, as well as honorary member of many associations and societies.

Bischoff’s, scientific work began with zoological and botanical research. Next he wrote on physiological and physiological-chemical subjects. His most important works concerned the embryology of mammals and of man. While he worked in Munich, he stressed anthropological research. In addition, throughout his life he remained interested in general problems of natural philosophy and religion.

Bischff’student papers on Helix pomatia and dragonflies were never printed, but his Ph.D. thesis on the spiral vessels of plants was published. His interest in physiological problems is shown in his treatises on the electric nerve currents (1841) and the reabsorption of narcotic toxins (1846). Also of interest is his his attempt to determine the amount of blood in a fresh corpse (1856). In Heidelberg he conducted —jointly with P. G. von Jolly—the first, but relatively unsatisfactory, experiments concerning blood-bound oxygen and carbon dioxide.

Although Bischoff was neither inclined toward nor particularly gifted in vivisection, he developed an interest in embryology while an intern in Berlin. In this field he achieved excellent results. He began with research on the human fetal membrane and was able to demonstrate the existence of the decidual vessels and the amniotic epithelium. In Bonn he was the first to lecture before a large audience on the history of embryology. His interest in this subject had been aroused by the work of Karl Ernst von Baer, a disciple of Ignaz Döllinger, on the existence of the mammalian ovum in the graafian follicle (1827) and on the subsequent formation of embryonic epithelia through a process of segmentation.

In 1835 Bischoff showed the canine ovum moving through the fallopian tube. This achievement formed the starting point for a series of related research. At the Freiburg convention of natural scientists and physicians (1838) he reported on the presence of sperm in the peritoneal sac of the ovary of a bitch some twenty hours after copulation. He deduced that the follicle was made to burst by the entering sperm. Next, in answer to a contest problem posed by the Berlin Academy of Sciences, he investigated the first phases of mammalian development in the rabbit. Bischoff was the first to clarify the successive division of the mammalian ovum and the first subsequent segmentation processes. He also demonstrated that the embryonic vesicle consists of cells. This finding enabled him to establish the connection between embryology and the then new science of cytology.

In this work there arose controversies regarding the choice between epigenesis and evolution. Bischoff considered the embryo be a liquid-filled vesicle, and attempted to derive the cellular substance of which the embryo is formed from the cellular beads of the morula. His history of the development of the rabbit egg was printed in 1842, that of the canine egg in 1845, of the guinea pig egg in 1852, and of the doe egg in 1854. His Entwicklungsgeschichte der Saugetiere und des Menschen was also translated into French, as were several other of his works.

At that time many scientists were doing research on embryology, with the result that all sorts of controversies and priority feuds arose. In 1843 Bischoff was compelled to correct his former views when it was found that ovulation occurs periodically, independent of copulation, and that subsequently the ovum commences its movement through the fallopian tube. His paper on this appeared in 1844 in German and in 1847 in English. His studies on the embryology of the guinea pig showed some remarkable difference from all prior observations. Of importance in this connection was Bischoff’s clarification of the fertilization process in the doe: after being fertilized in August, the egg moves within few days through the fallopian tube into the uterus and remains there for four and a half months without any further important development. In 1854 Bischoff had to correct his former views on one not unimportant point. It had been found, particularly by Barry (1843), that in the fertilization process the sperm penetrated the mammalian ovum. This had been disputed by Bischoff.

In 1859 Drawin’s On the Origin of Species appeared. Bischoff then decided to change his field of research, and began to occupy himself more and more with anthropological investigations. While he approved the theory of selection in principle, he considered the general theory of the origin of species to be insufficiently substantiated, since it did not furnish any explanation for the general and individual origin of life. This criticism resulted from Bischoff’s assumption that specific vital forces are active in development whereby “individual immortal basic causes” unite with matter. Although he closely related the activity of the soul with that of the brain, he nevertheless felt that the immortal basic cause of the individual continued to exist after death halted the soul’s activity. Such ideas are also expressed in his posthumously published treatise Gedanken eines Naturforschers über die Natur und über die Religion (1878).

In connection with the question of man’s place in the living world, Bischoff investigated the cerebral convolutions (1868) and the weight of the human brain (1880). He also studied the weight of the brain in relation to sex, body weight, body size, age, and race, and found no relationship between intelligence and brain weight. He did, however, consider the possibility of certain parallels. Bischoff’s studies on the anatomy of the anthropoid apes also belong to this group of works.

Among Bischoff’s physiological works particular mention should be made of those resulting from collaboration with or suggestions made by the great chemist Justus Liebig. In 1843, when Bischoff came to Giessen, Liebig’s influential books Die chemie in ihrer Anwendung auf Agrikultur und Physilogie (1840) and Die Tierchemie… (1842) had been published. The Wealth of ideas formulated in these works stimulated Bischoff’s interest in the metabolic processes. At that time scientists were beginning to investigate more closely the transformation of certain foods and their metabolic products. Liebig considered urea to be the measure of the protein metabolism in the tissue, whereas F. H. Bidder and Carl Schmidt interpreted it merely as the result of the actual amount of protein in the food. In Bischoff’s Der Harn als Maass des Stoffwechsels (Giessen, 1853), which was dedicated to Liebig, the findings of Bidder and Schmidt are corroborated, but the production of urea is ascribed to the metabolism of nitrogen-rich substances. Liebig’s theory of nitrogen-containing structural foodstuffs and respiratory nitrogen-free foods is substantiated. In Munich, Bischoff had Carl Voit as his collaborator. They jointly investigated nutrition in carnivores (1860) under conditions of starvation, an all-meat diet, and an all-fat diet, among others. Fat and similar substances were considered to be heat producers, nitrogen-containing substances to be energy producers. Subsequently, Voit founded the Munich school of metabolic physiology.

Bischoff had a gift oratory and was a popular babquent speaker and eulogist. His eulogies of Johannes Mu"ller and Friedreich Tiedemann and his address honoring Liebig’s achievements in physiology are valuable documents in the history of natural science.

Somewhat peculiar is Bischoff’s brusque rejection of women as university students in Das Studium und die Ausübung der Medizin durch Frauen, beleuchtet durch Dr. Th. L. W. v. Bischoff (1872). According to him, unqualified, half-trained female “artisans” impede and “most disastrously” disrupt the further development of medicine. Bischoff’s life was filled with unflinching scientific labor, involving experiments, preparations, observations, comparisons, readings, and weightings. He investigated many subjects and left indelible marks on many areas. His vigor and his strong will, his firm character and integrity are testified to by all biographers.

BIBLIOGRAPHY

I. Orginal Works. Complete bibliographies of Bischoff’s works are in the biographies by Kupffer and Sudhoff (see below). Among his major writings are “Berichte über die Fortschritte der Physiologie,” in Johannes Müller, ed., Archiv für Anatomie, Physiologie und wissen schaftliche Medizin für die Jahre 1839–1847; Entwicklungsgeschichte des Kaninchens (Brunswick, 1842); Entwicklungsgeschichte der Säugetiere und des Menschen, Vol. VII of Samuel Thomas von Sömmering’s Vom Baue des menschlichen Körpers, new ed. (Leipzig, 1843); Beweis der von der Begattung unabhängigen Periodischen Reifung und Loslösung der Eier der Säugetiere und des Menschen (Giessen 1844); Entwicklungsgeschichte des Hundeeies (Brunswick, 1845); Entwicklungsgeschichte des Reheies (Giessen, 1854); Die Gesetze der Ernährung des Fleischfressers durch neue Untersuchungen festgestellt (Leipzig-Heidelberg, 1860), written with Carl Voit; “Über die Bildung des Säugetier-Eies und seine Stellung in der Zellenlehre,” in Sitzungsberichte der Königlichen Bayerischen Akademie der Wissenschaften zu München, 1 (1863), 242; Das Studium und die Ausubung der Medizin durch Frauen (Munich, 1872); Gedanken eines Naturforschers über die Natur des Menschen unjd über die Religion (Bonn, 1878); and Das Hirngewicht des Menschen, Eine Stuidie (Bonn, 1880).

II. Secondary Literature. Biographies of Bischoff with full bibliographies are Carl Kupffer, Gedächtnistede auf Theodor L. W. Con Bischoff, 28. III. 1884 (Munich, 1884); and Karl Sudhoff, “Bischoff, Theodor Ludwig Whilhelm (von),” in Hessische Lebensbilder, 3 (1928). 1–11. See also Allgemeine Deutsche Biographie, XLVI (1902), 570; Almanach der Königlichen Bayerischen Akademie der Wissenschaften (1875), pp. 182–187 (1878), pp. 133–134; Biographisches Lexikon der hervorragenden Arzte, 2nd ed. (Berlin-vienna, 1929–1935), II, 550–551; and Index Catalogue of the Library of the Surgeon-General’s Office, U.S. Army, Washington, Ist ser., II (Washigton, D.C., 1881), 72–73; 2nd ser., II (Washigton, D.C., 1897), 353–354.

K. E. Rothschuh