This is an important and early geological map by Sir Charles Lyell. Color-coded key identifies 20 different geological units. The map extends to about the 110th meridian to include the Republic of Texas, Arkansas, Missouri, and the North West Territory. Lyell had two major and controversial goals in publishing his work and this map: first, he endeavored to establish a strict uniformitarian theory of the earth's geology, and also to standardize the terminology and methodology employed in the science of geology. This theory posits that the laws of nature are unwavering through space and time. His map, along with James Hall's work of 1843, is a landmark improvement in geological representations and mapping.

References: Marcou & Marcou #34.

Condition: B

Issued folding with a "J. Whatman 1839" watermark, light toning, and moderate offsetting. There are short fold separations and a binding tear that enters the neatline at right, all of which have been closed with archival tape on verso.