Letter from W. W. Crosby to the Director of the National Park Service defending his placement of the dynamite near Grand Canyon Village. He states there is between 16-20 tons of dynamite.

Geological examination of the park canyonland, with description of the rocks, water sculping process, volcanic cones and outflows, and land erosion. This edition is Volume 2, 1977 reprint, of the author's 1882 monograph. Includes 12 color maps, 10 color views and is number 280/1500.