Filtering by
- All Subjects: maps
- All Subjects: Mining
- All Subjects: Matthes, François Émile, 1874-1948
- Creators: Hayden, Carl T.
- Creators: The Military engineer
Letter from Carl Hayden to George Otis Smith asking his advice regarding the mining of asbestos deposits in the Grand Canyon.
Letter from Carl Hayden to W. W. Bass asking his opinion on the proposed boundaries of the National Park. GC National Park written on the letter in red pencil.
Letter from Carl Hayden to W. W. Bass asking his opinion on the proposed boundaries of the National Park. GC Natl Park written on the letter in blue pencil.
Letter from Carl T. Hayden to Louis C. Cramton about potential prosecution of people with mining claims within park boundaries.
Letter from Carl T. Hayden to Alf Dickenson about mine locations within the park.
Letter from Carl Hayden to Hugh E. Campbell with an enclosed outline map of the proposed boundaries of Grand Canyon National Park.