This is Volume VIII of the National Academy of Sciences Biographical Memoirs series. It is read as 33 sections using the memoir headings. John Wesley Powell was a leading figure in the geological explorations of the West and helped establish the federal U.S. Geological Survey in 1879. He also led the Bureau of Ethnology and advocated for better treatment and study of Native American tribes and culture. He wrote a definitive study of the arid western U.S., advocating for thoughtful irrigation and land management practices. Powell predicted that water rights purchased by corporations, rather than tied to the land, would be a major political and environmental issue. John Wesley Powell was a scientific frontiersman. His life reveals the energetic working of a vigorous and independent personality, full of inspiration, power, and enterprise. He was a founder of major scientific organizations, including the National Geographic Society, Geological Society of America, and the Cosmos Club. Powell lived most of his life in Washington, DC. The memoir was written by William Morris Davis was a prominent professor of geology, geography, and meteorology at Harvard and knew Powell personally.