Suddenly from far to the east there came the muffled thunder of heavy cannonading which brought all three men upright. For a moment they thought that real hostilities were on; but the illusion was not for long. The sporadic reply of their own batteries told them as clearly as words could that it was just “one of those messages from Fritz and Heinie” which of course required a reply, but did not after all amount to very much. It was a sort of exchange of compliments, the lads in the trenches termed it. Nevertheless every man was on edge, and when a simultaneous shout of warning and expectancy went up from two or three alert fellows who had been gazing skyward, a thousand heads went up, to witness one of those most daring and spectacular exhibitions of the entire war—a battle in the air. The three Brighton boys—for as such they were known to all their companions—rushed for an elevation already occupied by half a dozen others, and from which a wider sweep of the skyline was to be had. Even as they did so the real preliminaries to the battle began. The American pilot, who it was now plain had been merely playing the role of the pursued to lead the enemy beyond the aid of any of his own machines, suddenly swerved for the attack. The Boche pilot was in a small and speedy Albatross, but in maneuvres and tactics he was outmatched by the American, who came at him with such speed and directness that the witnesses, a thousand feet below, held their breath in expectation of a crash that would bring both machines and their pilots to the ground a battered, mangled mass. But the American pilot knew his game well. He swerved a little upward and over, just as the Hun took a swift nose dive to avoid contact. There was the rat-tat-tat of machine gun fire, that sounded from the distance more like the popping of toy guns. Neither made a hit, apparently, but the American plane had the position in which the Boche had to pass under, over or around him in any attempt to reach his own lines. The German had no heart for battle and headed straight south. Again the American came at him like a streak of lightning, began to climb at the same time, and the enemy tried a downward sweep and a turn northward at the same time. The American turned, too, and those on the ground began to applaud at the advantage he had gained. He was but a relatively short distance behind, but at a much higher altitude. As the Hun headed northeastward with all the speed he could get out of his Albatross, the American came down the wind, dropping as he came, and with momentum adding to the power of his propeller. When just within range he opened up with a fusilade from his machine gun. The German tried swiftly to change his course, but the effort was made too late.