Now You Know about John Wesley POWELL 1834 - 1902 Leader of the first expedition down the Colorado River through the Grand Canyon "We are three-quarters of a mile in the depths of the earth . . . . We have an unknown distance yet to run; an unknown river yet to explore. What falls there are, we know not; what rocks beset the channel, we know not; what walls rise over the river, we know not." - John Wesley Powell, Journal entry August...