This massive geological map uses vibrant printed color to highlight the deposits of igneous and sedimentary rocks across the states of Massachusetts and Rhode Island. An extensive key in the lower left outlines the various shades and symbols used within the image. Towns, the railroad network, and prominent geographic features are also labeled. The map was designed in 1916 by the noted American geologist Benjamin Kendall Emerson, using a base map from the U.S.G.S. Lithographed by Auguste Hoen & Company of Baltimore.
