----------------------------Original message---------------------------- The Digital Raster Graphics are indeed images and not databases. There is nothing that a GIS can do with them other than to use them as a backdrop ("wallpaper") for other covers. When I was given one of the early demo disks I wondered why USGS was doing this. In response to my query on GIS-L I received a long reply from the USGS listing a number of reasons all related to internal map production matters. I received only one other response from someone who found them useful. In that latter case the company had to deal with a state agency (Texas as I recall) that required them to submit their permiting requests, etc., as overlays to 1:24K quads. CDs are cheap, but this distribution still appears to me to be of very limited utility. -- Duane F. Marble E-mail: [log in to unmask] Dept. of Geography Home Page: http://thoth.sbs.ohio-state.edu The Ohio State University Telephone: (614) 292-2250 Columbus, OH 43210 Fax: (614) 292-6213