Topographic map of Salton Sea and vicinity /
Geological Survey (U.S.)
[Washington, D.C.] : Dept. of the Interior, U.S. Geological Survey,
1928.
Relief shown by contours, spot heights, and bathymetric isolines.
"Surveyed in 1925. Entire area mapped is below sea level."
"Control by U.S. Geological Survey. Datum is mean sea level. North American datum."
"5000 yard grid based upon U.S. zone system, F."