At last he caught sight of Tom's head, about ten feet away from the houseboat. A glance showed him that his brother was unconscious and on the point of sinking again.
"I must save him!" muttered Dick to himself, and, without an instant's hesitation, he leaped overboard.
"Dick! Tom!" The cry was uttered by Sam as he came running out of the houseboat, hatless and in his shirt sleeves.
The fallen tree obstructed his view, and it was several seconds before he caught sight of his brothers in the water.
"Dick!" he yelled. "What's the matter?"
"Throw me a rope," was the answer, and it did not take Sam long to obey instructions. Then Dick caught Tom under the shoulders, and both were hauled back to the side of the Dora.
"Did the tree knock you overboard?" asked Sam anxiously.
"It knocked Tom over," answered Dick.
Just as he was placed on deck again, Tom opened his eyes and stared around him.
"Who—where am I?" he demanded faintly.