Genth, Frederick Augustus

(b. Wächtersbach Hesse, Germany, 17 May 1820; d. Philadelphia, Pennsylvania, 2 February 1893),

chemistry, Mineralogy.

Genth exhibited a keen interest in natural history at an early age. After three years at the Hanau Gymnasium, in 1839 he entered the University of Heidelberg where he studied chemistry, geology, and mineralogy under Leopold Gmelin, J. R. Blum, and K. C. Leonhard. From 1841 to 1843 he attended the University of Giessen, where he worked under Fresenius, Kopp, and Liebig. In 1844 he continued his chemeical studies under Bunsen at the University of Marburg, receiving his doctorate there in 1845. He remained at Marburg as Privatdozent and Bunsen’s assistant for three years. In 1848 he immigrated to the United States, making his home first in Baltimore and then in Philadelphia. After occupying several positions, establishing one of the first commercial analytical laboratories in America, and engaging in the instruction of special students, in 1872 he became professor of chemistry at the University of Pennsylvania, a post he held until 1888, when he returned to consulting work and research.

Genth’s European background and education supplied him with technical skills possessed by few scientists in the United States during his lifetime, and he holds a place in the foremost rank of pioneer mineralogists in America. He was a chemist almost without peer, especially in the field of analysis. His best-known research involved the ammonia-cobalt bases (cobalt ammines), developed jointly with Oliver Wolcott Gibbs. His original memoir on this topic (1851) contained the first distinct recognition of the existence of perfectly defined and crystallized salts of the cobalt ammines. His joint monograph with Gibbs (1856) described thrity-five salts of four bases—rosecobalt Purpureocobalt, luteocobalt, and xanthocobalt— and for the first time distinguished roseosalts From purpureo salts.

Genth served as chemist for the Second Geological Survey of Pennsylvania and chemist to the Board of Agriculture of Pennsylvania; his analyses of fertilizers did much to develop the state’s agricultural industry. His chief chemical contributions to mineralogy are contained in fifty-four papers describing 215 mineral species; he himself discovered twenty-four new minerals. His contributions to chemistry and mineralogy Total 102.

BIBLIOGRAPHY

I. Original Works. Genth’s original memoir on cobalt ammines is in Keller-Tiedemann’s Nordamerikan Monatsbericht2 (1851), 8-12; Gibbs and Genth’s classic “Researches on the Ammonia-Cobalt Bases,” described by Genth’s student E. F. Smith as “among the finest chemical investigations ever made in this country,” appears in American Journal of Science, 2nd ser., 23 (1856), 234, 319, and 2 (1856), 86, and a separate publication in the series Smithsonian Contributions to Knowledge (Washington, D. C., 1856).

II. Secondary Literaure. The constitution of the cobalt ammines was not understood until Alfred Werner proposed his coordination theory in “Beitrag zur Konstitution anorganischer Verbindunger,” in Zeitschrift für anorganische Chemie, 3 (1893), 267-330, of which an English trans, is in G. B. Kauffaman, Classies in Coordination Chemistry I. Selected Papers of Alfred Werner (New York, 1968), pp. 9-88. On Genth’s life see especially his Student E. F. Smith, Chemistry in America (New York, 1918), pp. 261-263, and “Mineral Chemistry,” in Journal of the American Chemical Society, 48 , no. 8A (1926), 71-75. Additional data ate in George F. Barker“,: Obituary Notice; Frederick Augustus Genth,” in Proceeding of the American Philosophical Society, 40 (1901), x-xxii, and “Memoir of Frederick Augustus Genth 1820-1893,” in Biographical Memoirs, National Academy of Sciences, 4 (1902), 201-231; W. M. Myers and S. Zerfoss, “Frederick Augustus Genth; 1820-1893, Chemist-Mineralogist-Collector,” in Journal of the Franklin, Institute, 241 (1946), 341-354; H. S. van Klooster, “Liebig and His American Pupils,” in Journal of Chemical Education33 (1956), 493-497; and W. H. Wahl. H. F. Keller, and T. R. Wolf,” A Memoir of Frederick Augustus Genth,” in Journal of the Franklin Institute, 135 (1893), 448-452.

George B. Kauffman