Geologic Atlas of The United States, Three Forks Folio, Montana
United States Geological Survey, 1896. Soft cover. Large folio printed by Julius Bien & Co. 22" x 18.5". Folio 24 in the series, providing topographic and geological maps with explanatory text. An 'explanation' of basic geology by Charles D. Walcott is printed on the inside of the wrapper, 5 pages.....