Gustavus Sohon (1825-1903), a German immigrant, was employed by the U.S. government between 1852 and 1863 as an illustrator and cartographer of explorations of the Rockies and Pacific Northwest. Collection consists of eight tinted lithographs of scenes of the Midwest, primarily Montana, done for the U.S. Pacific Railroad Exploration and Survey Report, 1854-1855.

Collection consists of two green and black lithographs, "Mount Baker and Cape Disappointment" and "The Rocky Mountains from the Columbia River looking NW," and one hand-colored lithograph, "Falls of the Kamanis Taquoih River."