On December 12, 1893, U.S. Patent No. 510,758 issued to Cornele B. Adams of Augusta, Ga. on a Method of Photogrammetry:

Adams’ method employed aerial photographs from balloons at two different perspectives, which allowed the creation of topographic maps. Adams was not the first to employ aerial photography — in 1855 Gaspard Felix Tournachon used a balloon a 80 meters to take the first aerial photograph. (Four years later Napoleon III ordered Tournachon to take reconnaissance photography for the Battle of Solferino). Nor was Adams the first to employ aerial photography in the U.S. — on August 2, 1887, James Fairman was issued U.S. Patent No. 367610 on an Apparatus for Aerial Photography, which used a camera hung from either a balloon or kite, with a shutter operated by a timer. However Adams’ use of two separate images allowed him to accurately represent not just horizontal distances, but vertical distances as well.