Their own aerodrome lay only a few miles opposite. By actual and repeated reconnaissance both from below and in the air, this bluff was considered as deserted, or held at most by a very small force. This was owing to its supposed isolation. Evidently Erwin had just made a great discovery. At least he hoped so. On he flew. His machine was hit in many places, principally the wings, the tail and along the under side of the fuselage. Through this had come the ball that nearly perforated the tank. There was one more opening ahead and then the trench sank out of sight near the base of the low bluff. Orry's hand closed over the first grenade. He was really an expert bomb-thrower. At great risk he dipped gradually until, when about at the point overhead he desired, he threw two bombs in swift succession. Then-up, up rapidly. With all the power of his engine he climbed, while two sharp explosions sounded from below. Had the lad looked down he would have seen the trench walls at the open space crumble inward, while the mass of moving gray appeared to disintegrate, to vanish for the time being. But with the throwing of the bombs, Erwin had other work on hand. Archie had broken loose again. One larger molded shot ripped through the tail of the Bleriot, ricocheted obliquely and hit that same tank again, but with more force. His head lowered, the lad saw what had been done. More than that he saw what impended. The petrol was low. Being under fire, at any moment a stray shot might ignite what little was left. Pointing the machine still more upward, he seized a bunch of loose lint, used to sop up recurring leaks here and there, and with a handy screw driver he managed to stop the rent in the metal with a few sharp adroit punchings. Again to the machine, now over and beyond the bluffs; over the crinkling muddy stream, now almost overflowing its banks. On the bluff behind a squad of men in gray were training one of the Archies that had been dragged up from somewhere underneath. "I've got to give her all the head she'll take," he thought. "That gun will get me if they understand their business." Over beyond the stream a low embankment rose well up at perhaps three to f our hundred yards from its first bank. Erwin was rising in a steep climb, zigzagging crazily for the machine was giving out, owing to lack of fuel. But he made a last effort to thus dodge the rain of bullets that began to pelt upon him from the rear. Another larger gun came up. Both joined in firing. A shell splinter struck his shoulder, tearing loose the leather garment, while a searing, hot agony seized him, paralyzing his left arm.