In the hush of alarm Bob gave a sudden cry. “Fool that I am! I forgot the other man, Karl’s helper in von Eckhardt’s boat! Come, Harding!”

He plunged down the steep path, Major Harding at his heels, and in five minutes reached the riverside.

Rogers and von Eckhardt were still in the motor-boat, but Rogers was leaning over the side, a smoking pistol in his hand. Von Eckhardt was shouting orders across a dozen feet of water to his own boat, which, navigated by the pilot’s clumsy assistant, was getting under way, towing after it the loaded barge, unloosed from its moorings.

“Jump in, Dick! Hurry! We must turn back that boat!” cried Bob with mounting excitement.

He jumped in beside Rogers and von Eckhardt, followed by Major Harding. “Start her up! Get in front of that fellow and head him off!” Bob panted.

Rogers handed him the pistol and sprang to the engine. Von Eckhardt, stopping his frenzied directions, stood motionless, watching his boat, which had now got into the current and was making fair speed up-stream, the barge in tow.

Rogers pushed off and rapidly gave chase. The race was lost for the German boat from the beginning. Von Eckhardt sank down on the seat and sat staring at the floor.

While the boat overtook its quarry Rogers gave a hurried account of what had happened.

“You told me to shoot, sir, so when this fellow here began shouting out to his friend and telling him, as I made out by his gestures mostly, to come over and untie the barge and tow it off, I threatened to fire. But he defied me and said, 'Shoot away.’ I couldn’t just make up my mind to shoot him down like that, so instead I began firing at the other boat, hoping to cripple it. In the moonlight my shots went rather wild. I think I hit the other German. He cried out——”

“Yes, looks as though you had,” said Major Harding, pointing to the German pilot, who, steering with one hand, held the other pressed against his right shoulder.