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.

Letter from Ralph H. Cameron asking to speak to Carl Hayden concerning a matter relevant to the bill granting National Park status to the Grand Canyon.

Letter from Ralph H. Cameron to Carl Hayden requesting a delay on the introduction of the Grand Canyon bill until he can meet with himself and Senator Ashurst in Washington.

Letter from Ralph H. Cameron to Carl Hayden thanking him for forwarding Senate Bill No. 390 with the report of March 31st, 1918, and expressing interest in their upcoming meeting in Washington.