Map of the General Progress (Western Part)

An interesting thematic map of the western half of the United States showing hydrography, state and territory boundaries, and the progress areas of the geodetic surveys. Primary, secondary, and tertiary triangulations are shown as well as the reconnaissances and actual topography that has been surveyed. Also depicted are the lines of deep-sea soundings in the Gulf of Mexico, and the east coast waters. This map matches up with the eastern United States sheet.

IMPORTANT NOTE:

All of our United States Coast Survey (USCS), United States Coast & Geodetic Survey (USC&GS), and similar maps and charts have been professionally unfolded and flattened using humidity baths, semi-permeable membrane, and drying blotter techniques.  Most others you typically see on eBay have not been, and worse, are quickly and crudely unfolded for the low-quality photos you see.  Unfolding these maps in that way is damaging and weakens them. Please be aware.