British flying men played an important part in the Battle of Loos and in the preparations that preceded it. Troops and guns had to be moved at night so that the German aeroplanes might not note the concentration. Hence it was decided that British aeros should warn off the German flyers by day. They probably outnumbered the German machines by eight to one. As the attack proceeded a flock of aeroplanes was cutting circles and dipping and turning over the battle field as if in an exhibition of airmanship. They appeared to be disconnected from the battle, but no participants were more busy or intent than they. All the panorama of action was beneath them; they alone could really "see" the battle if they chose. But each aviator stole only passing glimpses of the whole, for each one was intent on his part, which was to keep watch of whether the shells of the battery to which he reported were on the target or not. To distinguish whose shell-burst was whose in the midst of that cloud of dust and smoke over the German positions seemed as difficult as to separate the spout of steam of one pipe from another when a hundred were making a wall of vapor. Yet so skilled is the well-trained airman that he can tell at a glance. It is not difficult to spot shells when only a few batteries are firing, but when perhaps a hundred guns are dropping shells on a half-mile front of trench, a highly trained eye is required. Occasionally a plane was observed to sweep down like a hawk that had located a fish in the water. At all hazards that intrepid aviator was going to identify the shell-bursts of the batteries which he represented. The enemy might have him in rifle range, but they were too busy trying to hold up the British infantry to fire at him. Other aeroplanes were dropping shells on railway trains and bridges, to hinder the Germans, once they had learned where the force of the attack was to be exerted, from rushing reenforcements to the spot. For that kind of work, as for all reconnaissances, the aviators like low-lying clouds. They slip down out of these to have a look around and drop a bomb--thus killing two birds with one stone--and then rise to cover before the enemy can bring his antiaircraft guns to bear. [Illustration: German infantry storming a hill in the Argonne. The men bend low for safety, though pressing eagerly forward toward the enemy's lines.]