Gus followed. When they rose again, the shark was but a few feet away. They could see him getting ready to turn over, preparatory to opening his jaws for a snap at either one or the other.

The monster turned toward Gus. The stout youth gave another cry of terror.

“Help! Help!”

Then Oliver thought of the knife still in his hand. Grasping the handle of the weapon firmly, he swam up, and buried the blade deeply in the shark’s head.

There was a wild slashing of the monster’s tail, and the water was dyed crimson. A moment later the boat appeared, and Gus was hauled in.

Then the shark turned his attention to Oliver. But the boy struck out firmly with the knife, once, twice, three times; and then the shark turned over and floated off—dead.

“The bravest deed I ever saw!” cried Mr. Willett, as they helped Oliver into the boat. “After this don’t dare to tell me the age of heroes is gone by.”

“Can we get that shark?” panted Oliver. “I—I would like to keep some part of the fellow as a remembrance of this event.”

“We’ll haul him on board,” said Mr. Willett. And later on this was done.

When they turned their attention to Gus they found that he had fainted. It took fully a quarter of an hour’s work to restore him to consciousness, and even then he was so weak from the terror of what had occurred that he had to lie down for the remainder of the day.