WHITNEY, JOSIAH DWIGHT, an American geologist; born in Northampton, Mass., Nov. 23, 1819; was graduated at Yale in 1839, and the year after joined the survey of New Hampshire. The years 1842-1847 he spent in study in Europe, returning to explore, together with J. W. Foster, the Lake Superior region. Their “Synopsis” of the explorations was published in 1849; their “Report” on the geology, 1850-1851. Whitney next spent two years traveling in the States E. of the Mississippi, of which the fruit was “The Metallic Wealth of the United States” (1854). Appointed State chemist and professor in the Iowa State University in 1855, together with James Hall, he issued the “Reports” on its geological survey (1858-1859); and in 1858-1860 took part in the survey of the lead region of the Upper Missouri, publishing, again with Hall, his “Report” (1862). He was appointed State Geologist of California in 1860, and labored on the survey of that State till 1874, publishing in six volumes his “Geological Survey of California” (1864-1870). In 1865 he was appointed to the chair of geology at Harvard, received the LL. D. degree from Yale in 1870, and had the honor of giving his name to one of the highest mountains in the United States. His “Yosemite Guidebook” was published at San Francisco in 1869; his “Contributions to American Geology” in 1880; and his “Studies in Geographical and Topographical Nomenclature,” in 1888. He died at Lake Sunapee, N. H., Aug. 18, 1896.