Elwyn Blake'S Colorado River Expeditions
by
Richard E. Westwood
Language: English
Release Date: March 1, 2013
The passage of the 1902 Reclamation Act created a mandate for the federal government to build dams on the Colorado River and its powerful tributaries. By 1920 the US Geological Survey had surveyed the river’s main courses, but still needed accurate charts of the last stretches of deep canyons and...