Flights flown between July 24, 1938 and September 6, 1938 by Iowa Aerial Surveys, Inc., for the U. S. Dept. of Agriculture, Agricultural Adjustment Administration. Photos numbered BGQ-1-3 through BGQ-4-31. Scale not given. Stereoscopic coverage. Only indexes are georeferenced.
JacksonCounty (Ill.) (W 89°41′--W 89°09′/N 37°57′--N 37°34′)
Illinois State Geological Survey
311 remote-sensing images, 2.02 gigabytes, average file 6.68 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.