It was evident that Paul Blum had no intention of seeking refuge in Barmet village. On the contrary, he was heading toward the other side of the bay, in the direction of the mouth of Willow River. "Perhaps he intends to go up the river," ventured Frank. Tony shook his head. "Not if he knows what's good for him. He'd run full plump into the falls and rapids near the old mill." "That's right, too." Frank had forgotten those obstacles. But while the _Sleuth_ was still some distance away from the mouth of the river, her speed began to slacken. "Good!" exclaimed Joe. "The gas tank's empty." "Let us hope so," returned his brother. "What a sell for that man!" But a moment later the other motorboat began to show signs of life again. "She's started up!" groaned Joe. "Confound the luck, anyway." A moment later a splutter came from the other boat. "Gas must be running low," said Frank. "Gee, I wish he would stop entirely!" "Same here." Slower and slower went the white motorboat until at last it was just crawling along. Frank picked up the binoculars again. He could see Paul Blum laboring at the motor, trying to locate the source of trouble. The fugitive cast a glance backward; Frank could see the anxious expression on the man's face. "He's trapped, and he knows it." Rapidly, they gained on the _Sleuth_, which was now almost at a standstill, drifting back and forth in the waves. Paul Blum seized an oar that was carried in the boat in case of emergency, and frantically began to scull toward the shore. But his effort was in vain. Tony's motorboat bore swiftly down upon him. The engine of the _Sleuth_ had died. As the other craft drew alongside, Paul Blum cast aside the oar in admission of defeat. He sat sullenly in the boat without looking up. "Too bad, Blum!" shouted Frank. "We're going to take you back with us." "I'd have been all right if it hadn't been for the confounded gas running out," gritted the man. "We weren't so particular about getting you as we were about getting back our boat," said Joe. "Will you come back quietly?" Paul Blum shrugged his shoulders. "I suppose I might as well," he said. "I haven't any weapons. If I had, you may depend on it, I'd put up a fight." "Just as glad you haven't, then," remarked Tony cheerfully. Carefully, he brought the boat alongside the _Sleuth_ and Frank and Joe jumped over the side into their own craft. Paul Blum was resigned. He submitted to having his wrists bound with a piece of stout rope that the boys found on the stern of the boat, and then he sat down philosophically. "I'll get away yet," he told them. "If I can't escape from that jail myself, my friends will see that I get out." "How will we get back?" asked Frank, turning to Tony. Paul Blum laughed. "That's a problem for you," he said. "The gas tank's empty. What are you going to do about it?" Tony calmly handed over the can of gasoline from his own boat.