"Go on back, unless you want to be shot!" cried the man savagely, but they paid no attention to the threat as no pistol appeared; and, seeing this, the thief redoubled his efforts to get away.
He was still a quarter of the distance from the opposite shore, and the boys on the tree were in midstream, when Sam uttered a shout. "There goes one of his oars! We can catch him now—if we try hard!"
It was true that the oar was gone, and in his anxiety to regain the blade the tramp nearly lost the second oar. But his efforts were unavailing, and he started to paddle himself to the bank, meanwhile watching his pursuers anxiously.
"We'll get him," said Dick encouragingly, when, splash! Tom went overboard like a flash, the lower end of his pole having slipped on a smooth rock of the river bottom. There was a grand splutter, and it was fully a minute before Tom reappeared—twenty feet away and minus his pole.
"Hi! help me on board, somebody!" he spluttered, for he had gone overboard so quickly that he had swallowed a large quantity of water.
Both Sam and Dick tried to reach him, but could not. Then the current caught the tree and whirled it around and around until both boys began to grow dizzy.
Seeing they could not aid him, and getting back a little of his wind, Tom struck out for the tree. But the water running over his face blinded him, and ere he knew he was so close the tree came circling around and struck him on the side of the head.
"Oh!" he moaned, and sank from sight.
"Tom's hit!" gasped Sam. "He'll be drowned sure now!"
"Not if I can help him!" burst out Dick, and leaped overboard to his brother's assistance. But Tom was still out of sight, and for several seconds could not be located.