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.

Grand Canyon National Park airport master plan, final report: inventory, aviation forecasts, demand/capacity analysis, airport requirements, airport plans, financial plan environmental review.