"Gray's Geological Map of the United States by Charles H. Hitchcock Ph.D. Professor Geology in Dartmouth College", Gray, Ormando Willis & Son

Very striking and graphic stone engraved thematic map that details the geological formations throughout the United States. The nine different geological structures are shown through fine coloring accomplished in free-hand. 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.

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Condition: A

Dark impression and bright original color. Hint of toning along centerfold, still very good.