tag:digital.library.illinois.edu,2005:/items/955cb830-82d4-0134-1f08-0050569601ca-3Iowa-Illinois, Clinton sheet : reconnaissance map2022-09-15T18:31:20Ztag:digital.library.illinois.edu,2005:Item/667862016-11-15T17:24:18Z2022-09-15T18:31:20ZIowa-Illinois, Clinton sheet : reconnaissance mapContour interval 20 feet.University of Illinois at Urbana-Champaign Library