"Gray's Geological Map of the United States", Gray, Ormando Willis & Son

Very striking and graphic engraved map that details the geological composition the United States. The nine different geological types are shown in different hand color. Locates Eozoic, Silurian, Devonian and Lower Carboniferous, Coal Measures and Permo-Carboniferous, Triassic and Jurassic, Cretaceous, Tertiary, Alluvium, and Volcanic. Includes political boundaries, major cities and watershed. The map is based on Hitchcock’s map for the American Institute of Mining and was published by O.W. Gray and Son of Philadelphia.

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Condition: A

A clean, bright example with light toning along sheet edges.