Wabash River Historical MapDigital scans of the "Mosaic of Wabash River, Indiana: Terre Haute to Logansport". Taken by the US Army Corps of Engineers, these are the very first aerial photos ever taken for commercial use. For further information, see:
Birdseye, C.H. (1940). "Stereoscopic Phototopographic Mapping". Annals of the Association of American Geographers 30. Page 11. Original print volumes are located in the Humanities, Social Science Library.