John Wesley Powell Quotes
John Wesley Powell (2003). “The Exploration of the Colorado River and Its Canyons”, p.268, Penguin
We have an unknown distance yet to run, an unknown river to explore.
John Wesley Powell (2003). “The Exploration of the Colorado River and Its Canyons”, p.268, Penguin
John Wesley Powell (2008). “Canyons of the Colorado”, p.397, Cosimo, Inc.
Smithsonian Institution, John Wesley Powell, Almon Harris Thompson, Elliott Coues, George Brown Goode (1875). “Exploration of the Colorado River of the West and Its Tributaries: Explored in 1869, 1870, 1871, and 1872, Under the Direction of the Secretary of the Smithsonian Institution”, p.55
John Wesley Powell (2008). “Canyons of the Colorado”, p.394, Cosimo, Inc.