John Wesley Powell 1834-1902, American geologist and ethnologist.

After the Civil War, in which he lost an arm at Shiloh, he was appointed professor of geology at Illinois Wesleyan College, Bloomington. He led geological expeditions into Colorado and Utah in 1867 and 1868 and in May, 1869, began, under the direction of the Smithsonian Institution, a geographical and geological survey of the Colorado and Green rivers. In the course of this expedition his party passed by boat through the Grand Canyon , a hazardous feat first described in his Explorations of the Colorado River of the West (1875) and later in his Canyons of the Colorado (1895). He was later engaged in geological and ethnological explorations in Arizona and Utah. His efforts toward the reorganization of rival surveys in the West were a factor in bringing about the establishment (1879) of the U.S. Geological Survey, of which he served as director from 1881 to 1894. In 1879, Powell founded and became the first director of the Bureau of American Ethnology. He remained there for more than 20 years, and many of his contributions to ethnology appeared in its Reports.  [ From Answers.com ]