And again. Great skill has been developed in the course of the war in the art of concealing positions and particularly in disguising cannon. The art has given a new word to the world--_camouflage_. Correspondents have repeatedly told of their amazement in suddenly coming across a battery of 75's, or a great siege gun so cunningly hidden in the edge of a thicket they would be almost upon it before detecting it. From an airplane 2500 feet or more in the air it requires sharp eyes to penetrate artillery disguises. A French poilu in a little book of reminiscences tells with glee how a German observation aviator deceived his batteries. A considerable body of French troops being halted in an open field, out of sight of the enemy batteries, found the glare of the sun oppressive, and having some time to wait threw down their equipment and betook themselves to the cool shadows of a neighbouring wood. Along came an enemy aviator. From his lofty height the haversacks, blanket-rolls, and other pieces of dark equipment lying upon the grass looked like a body of troops resting. After sailing over and around the field twice as though to make assurance doubly sure he sailed swiftly away. In a very few minutes shells from a concealed battery began dropping into that field at the rate of several a minute. Every foot of it was torn up, and the French soldiers from their retreat in the woods saw their equipment being blown to pieces in every direction. The spectacle was harrowing, but the reflection that the aviator undoubtedly thought that he had turned his guns on a field full of men was cheering to them in their safety.
An art which the fighting aviator must master early in his career is that of high diving. Many of us have seen a hawk, soaring high in air, suddenly fold his pinions and drop like a plummet full on the back of some luckless pigeon flapping along ungainly scores of feet below, or a fishhawk drop like a meteor from the sky with a resounding splash upon the bosom of some placid stream and rise again carrying a flapping fish to his eyrie in the distant pines. The hunting methods of the hawk are the fighting methods of the airman. But his dives exceed in height and daring anything known to the feathered warriors of the air.