Keywords: stereoscopic stereophotography stereophotographs historical usgs history geology mapping black and white blackandwhite bnw stereograph blackandwhite monochrome outdoor black and white Two boats in Marble Canyon, Colorado River. Major Powell's armchair in on one of the boats. Grand Canyon National Park. Coconino County, Arizona. 1872. (Stereoscopic view) Two boats in Marble Canyon, Colorado River. Major Powell's armchair in on one of the boats. Grand Canyon National Park. Coconino County, Arizona. 1872. (Stereoscopic view) |