Before he could fly his machine on the battle-front the French flier had to know how to loop, to fall or dive at such a steep angle that his machine actually dropped through the air for several hundred feet before it flattened out—a tremendous strain on the wings of a machine—to side slip or round a curve with his machine banked at such an angle that it gradually slid toward the centre of the circle, to climb or tail dive at such a pitch that the aircraft actually slips backward tail foremost. Indeed, in the last days of training the student was encouraged to practise all kinds of stunts and tricks, for when an enemy descended on you from the clouds above and was sitting on your tail weaving a wreath of bullets from a machine-gun round you, your only chance of escape was by means of a loop, a dive, a side slip, or a roll. Another interesting test a pilot had to undergo before he got his license to do battle was to ascend fifteen hundred feet, cut off all power, and volplane down in a spiral to a fixed point. To perform the manœuvre successfully required great skill. All the members of the famous Lafayette Escadrille had to undergo those tests before becoming fighting aviators, and Americans who received their final training in France had to go through the same training. In our government flying-schools at Mineola in Long Island and the other flying-fields in Texas and other parts of the country, at San Diego in California, the students were put to similar tests of skill. In the private civilian schools, however, instructors rarely attempt to teach their pupils more than straight flying. But most aviators agree that every flyer ought to know the “stunts” in order to meet successfully any extraordinary situation that may confront him. Of course the training for aerial observers, wireless operators, and photographers was very different from that of the pilots. In each case the instruction was peculiar to the science they were to practise, and it had little to do with aviation, only in so far as it was actually affected by flying. The men who took the pictures had to make a study of the science of photography. The same was true of the wireless operator. The observer, however, had to study topography and the use of the machine-gun, and target practice such as characterized the work of the pilot. In different countries this differed with the methods developed there. In England the pilot often shot at toy balloons in the air while chasing them with his machine or at targets on the ground. The same method was employed by the United States. Nearly all the great aces in the war were very clever shots, and Major Bishop attributed most of his success to his skill with the machine-gun.