It has frequently been said that the camera does not lie, but such assertions were made before the Camouflage Corps commenced its operations. Thereafter the negatives brought in by the German airmen began to prove so unreliable that the officers whose business it was to interpret them never knew whether they were telling the truth or not. For example, it frequently became necessary after heavy bombardments in which long stretches of entanglements had been destroyed, to convince the enemy that the wire had been repaired. This illusion was accomplished by the simple stratagem of driving stakes into the ground and festooning them with fish-nets, for, in a photograph taken from the sky, fish-nets thus arranged are indistinguishable from wire. If such ruses are to deceive the enemy, however, as much attention must be paid to detail in their execution as David Belasco pays to detail in the production of a play. On a certain British sector a not overintelligent subaltern was ordered by his battalion commander to take a working party and put out some 500 yards of this imitation wire, as there was reason to believe that the Huns, thinking the sector unprotected by entanglements, were preparing to make an attack. Now it is some job, even for a large and well-trained working party, to put out 500 yards of wire in much under a day. Heedless of such minor details, however, the lieutenant gayly slammed in his stakes and spread his fish-nets as fast as his men could work, “wiring” the 500 yards of front in little more than an hour. From high in the blue German airmen photographed the proceeding. When one set of photographs showed a sector destitute of wire and another set of pictures, taken an hour later, showed the same area with a complete system of wire entanglements, the suspicions of Von Hindenburg’s intelligence officers were naturally aroused, and the next morning at dawn the Germans launched their attack. In camouflage work one can’t afford to be slipshod.