John Wesley Powell

John Wesley Powell (March 24, 1834 – September 23, 1902) was a U.S. soldier, geologist, explorer of the American West, professor at Illinois Wesleyan University, and director of major scientific and cultural institutions. He is famous for the 1869 Powell Geographic Expedition, a three-month river trip down the Green and Colorado rivers, including the first known passage by Europeans through the Grand Canyon.

• http://en.wikipedia.org/wiki/John Wesley Powell