Humboldt University of Berlin, Unter den Linden 6, 10099 Berlin, Germany
From 1838 Ernst von Brücke studied medicine at the University of Berlin (now Humboldt University of Berlin). He was graduated as a doctor of medicine and surgery in November 1842.
Austrian Academy of Sciences, Dr. Ignaz Seipel-Platz 2, 1010 Vienna, Austria
In 1849 Ernst von Brücke became a member of the Austrian Academy of Sciences.
In 1875, Ernst Wilhelm von Brücke was awarded the Bavarian Maximilian Order for Science and Art for Science and Art.
Ernst von Brücke also received the Pour le Mérite (civil class).
Allgemeine Poliklinik, Mariannengasse 10, 1090 Vienna, Austria
Portrait medallion of Ernst Wilhelm von Brücke on the facade of the Allgemeine Poliklinik.
Brücke attended the Gymnasium in Stralsund and from 1838 studied medicine at the University of Berlin (now Humboldt University of Berlin). He was graduated as a doctor of medicine and surgery in November 1842.
According to the rules of the Berlin University at that time, candidates had to wait for two years between receiving the doctorate and habilitation as Privatdozent. It was thus not until the end of the year 1844 Brücke became Privatdozent the University of Berlin (now Humboldt University of Berlin), teaching physiology. But as early as in the autumn of 1843 he got a position as assistant at the Museum of Comparative Anatomy, of which Johannes Peter Müller, Brücke's final teacher as a student, was the director, and worked unofficially as a prosector, as the prosector, Wilhelm Karl Hartwig Peters was absent on a scientific journey.
In 1846, Brücke was elected teacher of anatomy in the Akademie der Bildenden Künste, in Berlin. Following that, in 1848 Brücke became a professor of physiology at the University of Königsberg (it was destroyed during World War II, and today the Immanuel Kant Baltic Federal University in Kaliningrad claims to maintain the traditions of the University of Königsberg), replacing Karl Friedrich Burdach. The following year, he went in the same capacity to Vienna, where he founded a school for physiologists that eventually extended far beyond the borders of Austria and there worked until his death.
Here, in the major city of a polyglot country, Brücke had an unusual opportunity to study linguistic and vocal physiology. To determine each sound of an arbitrary language in his own (alphabetical) characters and thereby to give a phonetic transcription was the aim of his Characteristics of the Physiology and Taxonomy of Linguistic Sounds (1856). With the aid of a labiograph, he made the first attempt to measure exactly the length of strongly and weakly accented syllables in verse. He recorded the results of these measurements in a monograph, The Physiological Bases of New High German Poetic Art (1871). There is unmistakably evident here a typical endeavor of the times (primarily to analyze the effect of a work of art rationally, i.e., by means of scientific methods), as is also the case in Brücke’s writings concerning the theory of art, which deal with the determination of the classical ideal of beauty.
It is said that Brücke was one of the most versatile physiologists of his day. His Lectures On Physiology (1873–1874) confirms this; in it, he added something of his own to almost every chapter. The diversity of his interests made limited specialization alien to Brücke. His investigations included the physiology of digestion; from 1850, Brücke studied the digestive tract microscopically and recognized the structures designated as Peyer’s "glands" as the places where the lymphocytes develop. He explained the mechanism of the transfer of chyle by means of the contraction of intestinal villi. In his work on chyle, which was published for the most part in the Proceedings of the Imperial Academy of Sciences in Vienna, he encountered an abundance of questions concerning the reabsorption of fats, carbohydrates, and proteins. As a result, he developed many biochemical concepts. Brücke introduced the terms "achroödextrin" and "erythrodextrin" into physiological chemistry; he discovered that blood did not coagulate in uninjured vessels, and he became a pioneer in enzyme research through his experiments on peptic digestion. With these experiments, he endeavored to produce the purest possible pepsin solutions. He tried to combine pepsin mechanically with small solid bodies such as calcium phosphate, sulfur, and cholesterol, and subsequently to extract it again from its adsorbates. He succeeded herein along two possible avenues of approach (through precipitation of calcium phosphate with water, or by treating the cholesterol precipitation with ether). But in order to reach his goal he needed control reactions for further purification, which he did not have.
Brücke is generally honored as a microscopist without it being pointed out that his microscopic investigations invariably grew out of his physiological inquiries and were determined by them. The investigation of function was his chief aim when he observed the flow of protoplasm in the stinging hairs of nettles or molecular motion in the salivary particles or - a classic example of the synthesis of histological, physical, and experimental methods - when he explained the changing of a chameleon’s colors by the momentary shifting movements of the skin’s pigment cells. Such diverse studies on the function of the most varied cells led Brücke to criticize the mechanistic ideas of structure in the cell theory of Matthias Schleiden and Theodor Schwann - of the cell as a shell formed by the cell membrane. While he and Max Schultze, a histologist from Bonn, were beginning to distinguish protoplasm as an essential cellular component, he was at the same time paving the way for a biological theory of cells in his investigation entitled The Elementary Organisms. In 1867 - 1868, with his experiments on the possibility of electric stimulation of muscles, Brücke moved into the specialty of his friend Du Bois-Reymond, i.e., general nerve and muscle physiology. Du Bois-Reymond held that the stimulating effect of an electric current depended solely on how fast such a current was increased in the stimulated organ and not on how long the stimulus lasted. Brücke, on the other hand, observed that in curare-treated frog muscles a current that was increased too slowly remained ineffective. Accordingly, in electric stimulation, the time factor had to be considered no less than the amount of current. In regarding the stimulus as a function of the "distance from the normal state," Brücke arrived at a new concept of the law on stimulation, which approximates modern concepts more closely than the first formulation by Du Bois-Reymond.
When Brücke resigned his teaching position from the University of Vienna in September 1890, he had 143 publications to his credit. The range of this output is made evident by the number of different areas of work: physics, plant physiology, microscopic anatomy, physiological chemistry, physiological optics, and purely experimental physiology.
Ernst Wilhelm von Brücke also was a member of the Academy of Sciences Leopoldina, the Royal Swedish Academy of Sciences, the Accademia dei Lincei, the Royal Prussian Academy of Sciences (now the Berlin-Brandenburg Academy of Sciences and Humanities), and the Bavarian Academy of Sciences and Humanities.