The river and the rocks
Subtitle: the geologic story of Great Falls and the Potomac River Gorge
By: [by] U.S. Geological Survey [and] National Park Service.
Contributors: United States. National Park Service.
Publisher: For sale by the Supt. of Docs., U.S. Govt. Print. Off.
Published: 1970
Place of publication: [Washington
Language: eng
Number of pages: 46
Subjects: Geology -- Great Falls of the Potomac (Md. and Va.); Natural history -- Great Falls of the Potomac River (Md. and Va.) -- Guidebooks.; Great Falls of the Potomac (Md. and Va.) -- Guidebooks.
Genres: Guidebooks.
Notes: Bibliography: p. 46.