The Journey Of The Corps Of Discovery. They called themselves the Corps of Discovery, yet they would fail to find the primary object of their mission: the Northwest Passage, a mythical all-river route through the mountains. Instead their real discovery would be the land itself--and the promises it held. The companion volume to Ken Burns's PBS documentary film, with more than 150 illustrations, most in full color. A moving and illustrated portrait of the Lewis and Clark expedition of 1804-6