William H. Jackson: Grand Canyon of the Yellowstone. 1872, Albumen print , arched top, from wet collodion negative, 9 x 12-3/4 in. (229 x 324 mm), on original Hayden Survey mount., Probably photograph #21 of the 11 by 14 inch series, on the second photographic expedition into Yellowstone Park. WHJ states (1874, U.S. Geological Survey of the Territories, Misc. Publ. #5, p. 38 "The Grand Canon of the Yellowstone, from a point directly over the Lower Falls and looking down. At this point the canon has an average depth of about 1,500 feet, and of about the same width at the surface. the view embraces nearly one mile of its length." w1737.