ZEUNER, GUSTAV ANTON

(b. Chemnitz [now Karl-Marx-Stadt. German Democratic Republic], 30 November 1828; d. Dresden, Germany, 17 October 1907)

mechanical engineering, thermodynamics.

The son of a cabinetmaker, Zeuner completed an apprenticeship in his father’s trade (1846). At the local trade school and through private study he acquired the background to enter the mining academy at Freiberg, Saxony. Working closely with Julius Weisbach, professor of mechanics and mining machinery and a notable hydraulics engineer, he became interested in applied mathematics and mechanical engineering and decided upon a teaching career. In the first years after his graduation 0 851-;1855), Zeuner was unable to find permanent employment in his native Saxony because of his participation in the 1849 uprisings in Dresden. In 1851 he visited Paris, where he met Poncelet and Regnault. Impressed by Foucault’s pendulum, he wrote a theoretical study of it, for which the University of Leipzig awarded him the Ph.D. in 1853. In 1854, with Weisbach and C. R. Borne-;mann, he founded the important journal Der Ch’ilIngenieur, of which he was the first editor (until 1857) and a major contributor.

In 1855 Zeuner was appointed professor of mechanics and theory of machines, and head of the mechanical department of the Federal Polytechnicum at Zurich. His years in Zurich were his most productive; he served as deputy director (1859-;1865, 1868-;1871) and director (1865-;1868) of the institution, and wrote his most important scientific works. In later years Zeuner was preoccupied with administrative duties, serving as director of the Freiberg Mining Academy from 1871 to 1875, and of the Dresden Polytechnical Institute from 1873 to 1890. He resigned the latter post in 1890, after reorganizing the school into an institute of technology, and retired from teaching in 1897.

Reflecting the influence of Weisbach, Zeuner’s earliest publications dealt with problems of hydraulics and water turbines, a subject to which he returned in his later years. Most of his works, however, were devoted to theoretical aspects of the steam engine. In a book on steam-;engine valve gears (1858) he proposed a graphical treatment of valve motion that was soon internationally accepted as the Zeuner diagram; other monographs dealt with steam injectors and the dynamic imbalances in the motion of locomotives. His main work, a comprehensive text on thermodynamics (1860), presented the first synthesis into a consistent system of the newly formulated first and second laws of thermodynamics and the improved understanding of the properties of steam (resulting from Regnault’s experiments). This book, which had lasting international success, was distinguished by its emphasis upon theoretical principles and by its deductive approach. It was later criticized for its failure to do justice to certain practical problems of the steam engine.

Zeuner also made pioneer contributions to mathematical statistics and insurance mathematics, in which he had become interested through a study of miners’ insurance systems done while he was a student.

Zeuner has been praised as a naturally gifted lecturer and teacher. Among his most prominent students were the engineers Carl von Linde and Hans Lorenz and the physicist Wilhelm Rontgen, whose doctoral dissertation (1869) he supervised.

BIBLIOGRAPHY

I. Original Works. Lists of Zeuner’s publications are in Poggendorff, 11, 1407-;1408: 111, 1481-;1482. IV, 1689: and V, 1410. His books are Die Schiebersteuerungen (Freiberg. 1858: 6th ed.. Leipzig, 1904), translated by J. F. Klein as Treatise on Valve Gears (London-;New York, 1884) and by A. Debize and E. Merijot as Trade des distributions par tiroir (Paris, 1869): Grundriige der mechanisehen Wiirnretheoric (Freiberg, 1860: 2nd ed., 1866), 3rd ed., enl., Technische Thermodvnamik, 2 vols. (Leipzig, 1887-;1890: 5th ed., 1905-;1906), translated by Maurice Arnthal as Tlteorie ntecanique de la chaleur (Paris, 1869) and by J. F. Klein as Technical Thermodvvna nics (New York. 1907): Das Loconurtiven-;Blasrohr (Stuttgart, 1863): Abhandlungen curs der mathematischen Statistik (Leipzig, 1869): and Vorlesungen fiber Theorie der Turbinen (Leipzig. 1899).

II. Secondary Literature. Biographical information on Zeuner. listed chronologically, is A. Slaby et al., "Gustav Zeuner," in Zeitschrift des Vereins deutscher Ingenieure, 51 (1907), 2049-;2050: R. Mollier. "Gustav Zeuner,” ibid.,52 (1908), 1221-1224; Verein Deutscher “Ingenieure, GustavZeuner, sein Leben and Wirken (Berlin, 1928): and Gustav Zeuner-;Schnorf, "Als junger Professor an die Hochschule berufen," in Neue Zurche r Zeitung, no. 2812 (22 Oct. 1955); and "Rontgens Doktorvater in Zurich," in Technische Rundschau (1958).

Otto Mayr