"Dash his impudence," growled the captain. "Slap at him again, just for luck." The only effect the resulting slap at him had, however, was to show the 'plane pilot that he was well out of range and to bring him spiraling steeply down a good thousand feet. This brought him within reach of the shells again, and both guns opened rapidly, dotting the sky thickly with beautiful white puffs of smoke, through which the enemy sailed swiftly. Then suddenly another shape and color of smoke appeared beneath him, and a red light burst from it flaring and floating slowly downwards. Another followed, and then another, and the 'plane straightened out its course, swerved, and flashed swiftly off down-wind, pursued to the limit of their range by the raving pom-poms. "Which it seems to me," said the Blue Marine sergeant reflectively, "that our Tauby had us spotted and was signaling his guns to call and leave a card on us." That afternoon showed some proof of the correctness of the sergeant's supposition; a heavy shell soared over and dropped with a crash in an open field some two hundred yards beyond the outermost house of the hamlet. In five minutes another followed, and in the same field blew out a hole about twenty yards from the first. A third made another hole another twenty yards off, and a fourth again at the same interval. When the performance ceased, the captain and his lieutenant held a conference over the matter. "It looks as if we'd have to shift," said the captain. "That fellow has got us marked down right enough." "If he doesn't come any nearer," said the lieutenant, "we're all right. We won't need to take cover when the shelling starts, and even if the guns are shooting when the German is shelling, the armor-plate will easily stand off splinters from that distance." "Yes," said the captain. "But do you suppose our friend the Flighty Hun won't have a peep at us to-morrow morning to see where those shells landed? If he does, or if he takes a photograph, those holes will show up like a chalk-mark on a blackboard; then he has only to tell his gun to step this way a couple of hundred yards and we get it in the neck. I'm inclined to think we'd better up anchor and away." "We're pretty comfortable here, you know," urged the lieutenant, "and it's a pity to get out. It might be that those shots were blind chance. I vote for waiting another day, anyhow, and seeing what happens. At the worst we can pack up and stand by with steam up; then if the shells pitch too near we can slip the cable and run for it" "Right-oh!" said the captain.