The Air Force is the eye of the army, and the camera the recording eye of the airman. It is therefore, of prime importance that aerial photography in all its phases be mastered by the would-be pilot. Failure cannot be risked. Too much is involved in sending machines on long photographic reconnaissance. Their results should indicate everything from a narrow path through enemy wire to a camouflaged German aerodrome.

In order to secure the best type of instruction, the R.A.F. has availed itself of the services of officers of experience on all points. Training begins at the School of Aeronautics. Here ground tuition is given, including everything from camera mechanism to colour filters and panchromatic plates, from map making to mosaics, the relative size of objects and the value of shadows in estimating heights.

Leaving the School, the cadet takes to the air to be tested by photographing given points, his ground instruction still proceeding. In the case of the observer, the course is the same, and all such work forms part of a general mapping scheme which aimed at the compiling of a complete reproduction of the areas around the several aerodromes.

Bad weather, usually considered a bugbear, is not allowed to interfere. By the use of a wide shutter slit and the very best lenses, tests are made in all weathers, and active service conditions thus paralleled. That photographic instruction has been faithfully given and intelligently received, may be seen from the excellent reproductions of aerial work presented in this volume.

From the foregoing it might be assumed that the art is simply acquired, but such is not in any way the case. To use his lens with complete facility, the pupil must correctly establish his height, his relative position with the objects to be photographed, and, generally speaking, be sufficiently at home in the air to do his flying instinctively and devote his chief attention to the camera.