In a region of hostile Indian-held territory, U.S. Army topographers mapped the High Plains of Texas and much of western America under adversity, seeking both scientific data and routes that would open the way for settlers. Earlier travelers such as conquistadors and mountain men had passed through and recorded their experiences, but the topographers mapped the terrain itself. The United States Army Topographical Corps, which from 1838 to 1863 consisted of 36 officers, used barometers, compasses, sextants, and pencils to gather data on climate, geographical features, soil, practical wagon or railroad routes, and locations for towns and industrial development. Three topographical parties investigated the land that is now Potter County: Lt. James W. Abert entered this Indian region in 1845 to survey the environs of the Canadian and other rivers; Lt. James H. Simpson in 1849 reconnoitered a proposed railroad route from Fort Smith to Santa Fe; and Lt. Amiel W. Whipple in 1853 mapped another railroad route from the Mississippi to the Pacific. These and other topographers earned great honor for their work.