Flights flown between November 21, 1938 and July 11, 1939 by Iowa Aerial Surveys, Inc., for the U. S. Dept. of Agriculture, Agricultural Adjustment Administration. Photos numbered BGJ-1-4 through BGJ-4-75. Scale not given. Stereoscopic coverage. Only indexes are georeferenced.
Edgar County (Ill.) (W 87°58′--W 87°31′/N 39°55′--N 39°28′)
Illinois State Geological Survey
299 remote-sensing images, 1.96 gigabytes, average file 6.71 megabytes
Scanned from 9 x 9 contact prints (nominal scale ca. 1:20,000) on Crosfield Celsis 6200 drum scanning system at 750 dpi. Quality assurance target not published but available by contacting the Illinois State Library Map Dept. MrSID files compressed at a target ratio of 6:1. Uncompressed TIFF images on cd available from the Illinois State Library Map Dept.