French chemist, meteorologist, aviator and editor Gaston Tissandier published La photographie en ballon. This pamphlet included a frontispiece consisting of an original photographic print by Jacques Ducom mounted on stiff card with a tissue overlay key. The key was thought necessary to explain the photograph because people were completely unaccustomed to looking at images from an aerial point of view.
The history of aerial photography began in 1858, when the photographer Nadar took the first photographs from a balloon. His results were only partially successful, as were those of other experimenters who followed him, and it was not until 1878, when factory-made gelatin dry plates were introduced, that aerial photography came into its own. Using gelatin plates, which were twenty times faster than the old wet-collodion plates, the photographer Paul Desmarets obtained two birds-eye views of Rouen in 1880 from a balloon at 4,200 feet. However, Desmarets' results were surpassed five years later by Jacques Ducom, who, in a balloon navigated by Gaston Tissandier, was able to take superb aerial photographs of Paris from a height of 1,800 feet.
"Ducom's view of the Ile Saint-Louis, Paris from 1,800 ft leaves absolutely nothing to be desired. Through a magnifying glass people can be counted on the bridge. The exposure of this and the other photographs taken on this flight was 1/50 second, using a specially constructed guillotine shutter which was opened pneumatically and closed automatically with a rubber spring" (Gernsheim & Gernsheim, The History of Photography 1685-1914 p. 508). Tissandier's La photographie en ballon records his and Ducom's achievements in aerial photography, and also surveys the work of Nadar, Desmarets, Shadbolt, Triboulet, Pinard, Weddel and other aerial photographers. The preface mentions the pioneering aerial photograph of Boston taken in 1860 by J. W. Black from a tethered balloon at 1,200 feet. Tissandier, who saw a print of Black's photograph, described it as "assurément fort curieuse, mais comme les précédentes elle manque de netteté et semble en outre avoir été prise très faible hauteur" (p. vi). Gernsheim & Gernsheim, pp. 507-8. Frizot, A New History of Photography, p. 391.