Map of Montana and Wyoming Territories, embracing most of the country drained by the Madison, Gallatin and Upper Yellowstone rivers. Geology by FV Hayden, assisted by AC Peale. Drawn by Henry Gannett from notes and sketches by Adolph Bruck, chief topographer of the Yellowstone Division of the United States Geological Survey of the Territories.

Map of the Snake River, with its tributaries together with portions of the headwaters of Madison and Yellowstone, surveyed by the Snake River Expedition (Gustavus R Bechler, chief topographer and James Stevenson, director) of the United States Geological Survey of the Territories.

Map of the Lower Geyser Basin on the Madison River after a reconnaissance by Gustavus R Bechler, chief topographer of the Snake River Division of the United States Geological Survey of the Territories.

Map of the Sources of the Snake River, with its tributaries together with portions of the headwaters of Madison and Yellowstone, surveyed by the Snake River Expedition (Gustavus R Bechler, chief topographer and Frank H Bradley, geologist) of the United States Geological Survey of the Territories.