| 1. |  | Illinois, Equality quadrangle : topography | Illinois; Maps; Topographic maps; Topography; Equality (Ill.) | 1 map : col.; Relief shown by contours and spot heights.; "Surveyed in 1913-1914."; "Contour interval 20 feet."; "Surveyed in cooperation with the State of Illinois."; Coordinates (W 88⁰30’00"--W 88⁰15’00"/N... |
