The 1870s was a period of intense effort, by such prominent people as Clarence King, Ferdinand Hayden, and John Wesley Powell, to advance the geographical knowledge of the West. These various surveys presented a threat to the Army's supremacy in the field of mapping and to the related appropriations from Congress. As a result of these pressures, the Army Corp of Engineers developed a plan to systematically survey the entire West to be called the U.S. Geographical Surveys West of the One Hundredth Meridian. The region was divided up into 95 rectangles, with atlas sheets to be prepared for each, comprising an area 2°45' of longitude and 1°40' of latitude on a scale of eight miles to the inch. Lieutenant George Wheeler was chosen to head this immense project. Surveys were conducted each summer from 1872 to 1878, after which Congress cut off appropriations for field work; thus the survey was not completed as originally envisioned. Wheeler published annual reports from 1873 to 1884, as well as the final Geographical Report published in 1889. The maps from this report are a valuable document of the record of Western exploration.

Part of North Central New Mexico, Atlas Sheet No. 70 (C) includes Santa Fe at the bottom and Taos at the top along the route of the Rio Grande River with the Gallina and Jemez mountains at the left of the map.

North Central New Mexico, Atlas Sheet No. 69 (D) is centered on the Turkey Mountains with Fort Union nearby, and extends west past the Canadian River and east to the Las Vegas and Taos mountain ranges. The map is criss-crossed with roads, including the Old Fort Leavenworth Road.

References:

Condition: A

Some minor marginal creases and a little soil.