Hayden Geological Survey of 1871
The Hayden Geological Survey of 1871 explored the region of northwestern Wyoming that later became Yellowstone National Park in 1872. It was led by geologist Ferdinand Vandeveer Hayden. The 1871 survey was not Hayden's first, but it was the first federally funded, geological survey to explore and further document features in the region soon to become Yellowstone National Park and played a prominent role in convincing the U.S. Congress to pass the legislation creating the park. In 1894, Nathaniel P. Langford, the first park superintendent and a member of the Washburn-Langford-Doane Expedition which explored the park in 1870, wrote this about the Hayden expedition:
We trace the creation of the park from the Folsom-Cook expedition of 1869 to the Washburn expedition of 1870, and thence to the Hayden expedition (U. S. Geological Survey) of 1871, Not to one of these expeditions more than to another do we owe the legislation which set apart this "pleasuring-ground for the benefit and enjoyment of the people"
The 1871 Hayden survey had its roots in the Pacific Railroad Survey bill passed by Congress in 1853 to find the best routes for railroads from the Mississippi to the Pacific coast. The bill spawned an era of federally funded Great Surveys undertaken by the Department of the Interior after the Civil War that brought together explorers, engineers, scientists and topographers in a common effort to chart the western U.S. Hayden along with John Wesley Powell, Clarence King and George Wheeler were the leaders of these great surveys.
In March 1871, a sum of $40,000 was appropriated by Congress to finance Hayden's fifth survey to explore mostly the territories of Idaho and Montana. Hayden was very familiar with Jay Cooke's desire to promote the Yellowstone region for the Northern Pacific Railroad and had attended Nathaniel P. Langford's January 1871 lecture in Washington D.C. on the Washburn-Langford-Doane Expedition to Yellowstone of the previous year. The $40,000 that was granted for Hayden's expedition was not available until July 1, the beginning of the fiscal year; however, the determined Hayden was still able to organize and equip his expedition with the help of the US Army, Fort Bridger and the railroads. After the passage of the Sundry Civil bill, Hayden immediately applied to the Secretary of War for permission to draw on equipment, stores, and transportation at frontier army posts. This was authorized, together with a small escort "when deemed necessary and the public service will permit." Likewise, the Union Pacific and Central Pacific Railroads agreed to carry Hayden's men and equipment without cost.
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