Photography from 20,000 ft. Small specks on road are troops. The number of troops in this particular movement was calculated exactly from this set of photographs. (The weather was dull when picture was taken and troops did not see airplane, otherwise an effort would have been made to conceal them)
1918 · Gelatin silver print, from loose-leaf album of aerial photographs from the Photographic Section, Air Service, American Expeditionary Forces, World War I
Image/paper: 17 × 22.2 cm (6 3/4 × 8 3/4 in.); Album page: 24.2 × 31.7 cm (9 9/16 × 12 1/2 in.)
Art Institute of Chicago