Who is Ferdinand V. Hayden from Beyond the Hundredth Meridian: John Wesley Powell and the Second Opening of the West and what is their importance?

Ferdinand V. Hayden is considered to have been Powell's rival for the funding and attention of the government in the field of geology and exploration of the West. He was in the West some ten to fifteen years before Powell. The two men did not always agree on the appropriate use of the land or its development.