SPURR, Josiah Edward. Atlas to Accompany Monograph XXXI on the Geology of the Aspect District Colorado. Washington, Julius Bien & Co., 1898. Lithographié en couleurs. Original brown publisher's cloth, lettered in gilt. 27 chromolithographed maps (2 are double-page) + 1 text volume. The atlas accompanied the monograph by Samuel Franklin Emmons (1841-1911), the head geologist in charge of the Colorado division of the United States Geological Survey. Emmons is also known for exposing the infamous diamond fields hoax in Colorado in 1872. The maps and geological cross-sections depict the topography and geology of Aspen, Tourtelotte, Hunter Park, Lenado, Aspen Mountain, and Smuggler Mountain. Includes the Aspen Special Sheet that shows the town and nearby mines.