----------------------------Original message---------------------------- In answer to the querry: " "National Geodesic Survey" is inscribed on it. Can anyone tell us what this means?" It is most likely stamped "National Geodetic Survey". To quote from the Coastal Mapping Handbook: The National Geodetic Survey [under the National Ocean Service all under NOAA] ...is responsible for establishing and maintaining the Nation's horizontal and vertical control networks. You might call 301-713-2877 (Horizontal Control section) if you need more info. Greg Durocher USGS-ESIC, Alaska