"Topographical Sketch of the Southernmost Part of the Port of San Diego, and measurement of the Marine League for determining Initial Point of Boundary between the United States and Mexican Republic as Surveyed by The United States Commission…", U.S. Government

This was the critical map of the Mexican Boundary Survey. Initial work had broken down over a Mexican demand that Mexico be given the port of San Diego, and the determination of the length of a league. It provides interesting detail in the vicinity of San Diego and, along with its companion map of the Vicinity of the Gila River (see lot #284), anchors the border determination. This map is full of interesting information and is visually very attractive with calligraphy title and large compass rose. The map gives the marine league as 5564 meters - the standard today. Surveyed by Andrew B. Gray, John B. Weller, Commissioner.

References: Wheat (TMW) #616.

Condition: B

Dark impression on sound paper. Issued folded now pressed and backed with archival tissue. Scattered foxing.