A simplified version of the diaries of Lewis and Clark; in an introduction, Schanzer explains how she condensed much of the excitement and adventure of the 40 volumes into this one. The book follows the route mapped out on the end papers, beginning with President Jefferson's request that the two explore the west, and ending when Lewis and Clark return two years later to St. Charles (near St. Louis), long after everyone thought they'd died. In that time the two men discovered many new animals and plants, met with Indian tribes, and created new maps of the uncharted territories. Schanzer often breaks up the page into a series of vignettes with captions, effectively covering many of their experiences in a small space. Her drawings include portraits of the members of the expedition and other details that make an already authentic text all the richer. (Picture book/nonfiction. 6-10)