In the meantime the shark came on rapidly. He was a big creature, with a cruel-looking mouth and teeth that were equally ugly.
At first he turned toward one of the sailors, who was swimming for the ship.
But a rope was thrown to the tar, and this he grasped and was hauled on board with all rapidity.
Then the shark turned for another of the sailors.
But this fellow was making for the small boat, and soon he was on board and safe for the time being.
Then the shark turned swiftly and came for Dave.
The youth dove at once, remembering that a shark can attack under water only with difficulty.
But the boy could not remain under the surface forever, and at last he had to come up, this time somewhat closer to the Swallow.
But the shark saw him and turned again to attack the young diver.
It was a critical moment, and Dave was about to give himself up for lost when a shot rang out, followed by another.