Flights flown between June 24, 1939 and July 24, 1939 by Midwest Aerial Surveys, Inc., for the U. S. Dept. of Agriculture, Agricultural Adjustment Administration. Photos numbered BWP-1-3 through BWP-3-85.
Carroll County (Ill.) / W0901900-W0894100 / N0421200-N0415600
Illinois State Geological Survey
219 remote-sensing images, 1.36 gigabytes, average file 6.36 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 12:1. Uncompressed TIFF images on cd available from the Illinois State Library Map Dept.
Mode of access: World Wide Web. System requirements: Plug-in or image viewer, ExpressView Browser plug-in available for download. System requirements for interactive map: Google Chrome best.