This is one of the earliest American geological maps, one year before one by William Maclure. It details the Connecticut River valley from Hadley to Chesterfield counties. A legend uses hand coloring to locate Primitive Rocks, Primitive Argillita, Secondary; and Alluvial structures. Below the map in its own border is "Traverse Section of Rock Strata from Hoosack Mountain to Eleven Miles East of Connecticut River." The map accompanies an article entitled “Remarks on the geology and mineralogy of a section of Massachusetts on Connecticut River, with a part of New-Hampshire and Vermont," which was published in the first volume of Silliman's renowned American Journal of Science, which is offered here with the map.

Hitchcock’s first geological article was termed “a remarkable one” by George Merrill [The First One Hundred Years of American Geology. New Haven: Yale University Press, p. 55] and noteworthy for its hand-colored map. Although Maclure had published a map covering a wider area, Hitchcock’s more detailed map included a profile of rock strata and was the earliest geological map of a region. For a detailed history of the map, article and other important geological articles in the volume, click here (pages 4-6).

448 pages with other plates and a small folding hand-colored map entitled A Geological Map of the North-West Part of Massachusetts (4.7 x 6.7"). Octavo, hardbound in quarter leather with tips over cloth boards.

References: Marcou & Marcou #193 & 195.

Condition: B

The colorful folding map has a number of small chips and separations along the lower fold that have been repaired on verso with archival materials along with one small recto repair. Text has light scattered foxing. Ex-library with the front free endpaper loose. Covers have light wear.