'Compiled from all available information by J.E. Spurr. Topographic base chiefly adapted from the maps of the Wheeler Survey.' 'U.S. Geological Survey, Bulletin No. 208, Pl. 1.' 'A. Hoen & Co. Lith. Baltimore, MD.' Relief shown by hachures and spot heights. Scale [ca. 1:950,000. 1 inch to approximately 15 miles] (W 120°--W 114°/N 40°--N 36°). Geological Survey bulletin, 208.