With a detonation that threw Tom and several other of the men flat upon the ground, a tremendous German shell exploded just ahead of them. It sent a great cloud of earth and rock into the air, and before they could arise a big tree, that had been completely uprooted by the projectile fell directly toward them. The others rolled out of the way, but Tom was not quick enough. One of the large branches pinned both his legs to the ground. As he tugged in vain to get his freedom, George Harper crawled over to him. “Lay still for a moment,” he instructed his friend, “I think I can get you out.” With bullets whistling and singing all about them, with now and then a shell screaming its death message almost into the pit where Tom lay an impatient prisoner, the two lads worked frantically, but to little avail. Although his legs lay in a slight depression, which left him free of the weight of the huge tree, he was nevertheless held fast, and at last Tom began to urge Harper to abandon him there until others came along. “I’ll dig you out,” his friend replied, at the same time poising his bayonetted rifle for the job of scooping out enough earth to permit Tom to slip his legs out of the trap. Harper was in that position when suddenly his eye caught something in the fallen tree which made him swerve suddenly. “You beast!” he cried, and with all the gathered force of his strong body he flung his rifle, as a primitive savage would a spear, into the nearby branches. Tom, looking at that instant, saw the bayonet sink to the hilt in a brutal-looking German who at that instant was bringing up his gun to fire upon them. With one agonized grunt he crumbled, and then lay still; and Harper, averting his head, recovered his weapon. Obviously the Boche had been an enemy sharp-shooter hidden in the upper branches of the tree, and until that moment had remained stunned by the force of the fall precipitated by a shell from his own lines. Harper set to work instantly to dig Tom out, but it was not an easy job. As he lay there, virtually helpless, gazing up at the sky and at the scores of aeroplanes dashing, dodging, cruising about, he gave a gasp of astonishment which also attracted his friend’s attention. With consummate daring a Boche pilot had dodged the apparently impenetrable American air defenses, and, with half a dozen planes pursuing and attacking him, was making straight toward a big anchored observation baloon that hung motionless in the air a little to the north of where the first wave of shock troops thus far had progressed. The tremendous pounding of the motors rose even above the din of big and little guns. From every point Allied planes were sweeping down upon the Hun machine, but before they could overtake him he had fired an incendiary bullet at the baloon with unerring aim.