REDTENBACHER, FERDINAND JAKOB

(b. Steyr, Austria, 25 July 1809; d. Karlsruhe, Germany, 16 April 1863 mechanics, mechanical engineering.

Redtenbacher grew up in Steyr, a city noted for its metal industry and sometimes called the “Birmingham of Austria.” His father, Alois Redtenbacher, a prosperous merchant and a man of considerable culture, did not favor the “humanist” education then conventional in the German upper classes and apprenticed his son, at age eleven, to a grocer (1820–1824). This experience developed in young Redtenbacher a sense of practicality and a reliance upon self-education. His decision to become an engineer was made in 1825, when he spent nine months as an assistant draftsman and surveyor in the Imperial Construction Department at Linz. Later in the same year he entered the Polytcchnikum of Vienna, where he studied mechanical engineering while also attending lectures at the university. His chief teachers were the engineer Johann Arzberger and the mathematician Andreas von Ettingshausen. After his graduation in 1829 he served for four years as Arzberger’s assistant in the chair of mechanics and theory of machines. In 1834 he became teacher, and later professor, of applied mathematics at the Obere Industrieschule of Zurich. Redtenbacher found his ultimate position when the Polytechnische Schule of Karlsruhe invited him to occupy the chair of mechanical engineering. He moved to Karlsruhe in 1841 and served there until his death in 1863.

Redtenbacher’s significance lies in his role as engineering educator. It was he more than anyone else who gave the German Technische Hochschule its characteristic structure, and it was he who conceived and propagated the particular blend of theory and practice that constituted the success of German engineering for the following century. His influence was equally great through lecturing, writing, and administration.

Redtenbacher’s literary production consisted mostly of textbooks. His own education had been theoretical, in the spirit of the École Polytechnique, and based on the study of Euler, Laplace, Poisson, Navier, and Poncelet. He soon realized that the theoretical insights contained in such works were difficult to apply in practice and that the practical engineers of the English tradition denied the relevance of theory. In all his activities Redtenbacher strove to bridge this gulf. In Zurich, during frequent visits to the water-wheel factory of his friend Caspar Escher, he recognized that the newly introduced water turbines presented an opportunity to demonstrate the utility of well-presented theory; a book on water turbines was his first work (1844). His desire to convince practical engineers of the value of theory comes out even more clearly in his Resultat fur den Maschinenbau (1848), his best-known work. This is a handbook with tables and formulas For the solution of all common mechanical engineering problems, presented without mathematical derivation. This work was supplemented by his Principien der Mechanik (1852), which provided the theoretical background, and by Der Maschinenbau (1862–1865), which concentrated on the art of engineering design. Besides a number of specialized books on steam engines, locomotives, and caloric engines, Redtenbacher also wrote a work of philosophical intent, Das Dynamidensystem (1857), a kind of mechanistic theory of atomism based upon ideas of Dalton, Poisson, and Cauchy.

As Redtenbacher’s administrative influence increased—he was soon the most famous professor, and after 1857 he was director, of the Karlsruhe Polytechnic—he was able to put his own conception of engineering education into effect. His students were required to serve apprenticeships in industry and were instructed in advanced mechanics and mathematics in a manner different from that of the École Polytechnique in its practical motivation and its irreverence toward formal rigor. For Redtenbacher’s model was not the tightly regimented Ecole Poly-technique but the liberal German university with its system of lecturing, its separate faculties, and its academic freedom. The example of Karlsruhe had great influence; in the planning of the Swiss Federal Institute of Technology (founded 1855), for instance, it was Karlsruhe, not the Ecole Polytechnique, that served as the exemplar, and Redtenbacher as the principal adviser.

BIBLIOGRAPHY

I. Original Works. Virtually all of Redtenbacher’s literary output consisted of books: Theorie und Bau der Turhinen und Ventilatoren (Mannheim, 1844; 2nd ed.t 1860); Theorie und Bau der Wässerrader (Mannheim, 1846; 2nd ed., 1858); Resultate für den Maschinenbau (Mannheim, 1848; 6th ed., 1875; 2nd French ed., 1873); Principien der Mechanik und des Maschinenbaus (Mannheim, 1852; 2nd ed., 1859); Die calorische Maschine (Mannheim, 1853); Die Gesetze des Locomotivbaues (Mannheim, 1855); Die Bewegungsmechanismen (Mannheim, 1857; new ed., 1861); Das Dynamidensystem: Gründzuge einer mechanischen Physik (Mannheim, 1857); Der anfängliche und der gegenwärtige Erwarmungs-Zustand der Weltkörper (Mannheim, 1861); and Der Maschinenbau, 3 vols. (Mannheim, 1862–1865; French ed., 1872).

II. Secondary Literature. There is no definitive biography of Redtenhacher. The most useful shorter works are the following (listed chronologically): Emil Kretzschmann, “Ferdinand Redtenbacher,“in Verein deutscher Ingenieure, Zeitschrift, 9 (1865), 246–262; Franz Grashof, Redtenbachers Wirken zur wissenschaft-lichen Ausbildung des Maschinenbaus (Heidelberg, 1866); Rudolf Redtenbacher, ed., Erinnerungsschrift zur 70-jcihrigen Geburtstagsfeier Ferdinand Redtenbachers (Munich, 1879); K. Keller, “Zum Gedachtnisse Redtenbachers,“in Bayerisches Industrie- und Gewerheblatt (1910), 351–355, 363–367; Franz Schnabel, “Die Anfiinge des technischen Hochschulwesens,“in Festschrift Technische Hochschtde Karlsruhe (Karlsruhe, 1925), 1–44; and “Ferdinand Redtenbacher,” in Blatter fur Geschichte der Technik, 4 (1938), 66–71; Heinrich Ebeling, Ferdinand Redtenbacher, Leben und Werk (Karlsruhe, 1943); Otto Kraemer, “Ferdinand Redtenbacher,” in Die Technische Hochschtde Fridericiana Karlsruhe: Festschrift zur 125-Jahrfeier (Karlsruhe, 1950), 79–84; Karl Lindner, Ferdinand JakobRedtenbacher% der Begriinder des wissenschaftlichen Maschinenbaues (Graz, 1959); and Johannes Korting,“Ferdinand Redtenbacher,“in Verein deutscher Ingenieure, Zeitschrift, 105 (1963), 449–451.

Otto Mayr