Letter from L. B. Williams to Carl Hayden regarding W. W. Bass' resistance to the park bill.

Letter from George Otis Smith to Carl Hayden regarding mining rights in the Grand Canyon.

Letter from Carl Hayden to George Otis Smith asking his advice regarding the mining of asbestos deposits in the Grand Canyon.

Letter from George Otis Smith, U.S. Geological Survey to Carl Hayden regarding asbestos mining prospects in the Grand Canyon.

Letter from W. W. Bass to Carl Hayden regarding the right to his property.

Letter from Carl T. Hayden to C. H. Gensler, Havasupai Indian Reservation, regarding Hualapai and Cataract Canyons geography.

Letter from C. H. Gensler, Havasupai Agency to Carl Hayden regarding boundary lines.

Letter to Carl Hayden, possibly from Jack E. Gavin, detailing a trip to Flagstaff and Winslow to gauge his political popularity. Several mentions of his opponent Senator Ralph T. Cameron.

Letter from Fred Harvey to Senator Carl Hayden on the diary of Padre Francisco Garcés and the lack of knowledge of U.S. citizens regarding the Hopi people.

Letter from Fred Harvey to Senator Carl Hayden on the diary of Padre Francisco Garcés and his entry on July 4, 1776.