"Oh, Jim!" she cried, "what is that? Look, look----" Jim looked and turned pale under his tan. "Great heavens!" he cried. "It's a shark!" The cry was taken up by scores. "A shark! A shark!" There, cleaving the water and coming toward the swimmer like an arrow at its mark, was a great black dorsal fin which bespoke the presence of the pirate of the seas. The steamer had lessened speed in order to lower its boat, but the momentum under which it was carried it within twenty yards of the castaway. Almost instantly the ship's boat struck the water, and the sinewy backs of the sailors bent almost double as they drove it toward the swimmer. From the crowded deck they could see his face now, pale and dripping, but lighted with a gleam of hope as he saw the boat approaching. But the horrified onlookers saw something else, that ominous, awful fin, that came rushing on like a relentless fate toward its intended prey. Some of the women were sobbing, others almost fainting, while the men, pale and with gritted teeth, groaned at their helplessness. It was a question now of which would reach the luckless man first, the boat or the shark. The boat was nearer and the men were rowing like demons, but the shark was swifter, coming on like an express train. There must have been something in those faces high above him that warned the man of some impending peril. He cast a swift look behind him, and then in frantic terror redoubled his efforts to reach the boat. "Oh, Joe, they'll be too late! They'll never reach him in time!" sobbed Mabel. "Oh, can't we do anything to help him?" Joe, as frantic as she, looked wildly about him. His eyes fell on a heavy piece of iron, left on the deck by some seaman who had been repairing the windlass. Like a flash he grabbed it. It seemed as though the swimmer were doomed, and a gasp of horror went up from the spectators as they saw that the boat would be too late. For now the fin had disappeared, and they saw a hideous shape take form as the monster came into plain sight, a foot beneath the surface, and turned over upon its back to seize its prey. Then Joe took a chance--a long chance, a desperate chance, an almost hopeless chance--and yet, a chance. With all the force of his powerful arm he sent the jagged piece of iron hurtling at the fiendish open jaws. And the chance became a certainty. The missile crashed into the monster's nose, its most sensitive point. The brute was so near the surface that the thin sheet of water was no protection. The effect was startling. There was a tremendous plunging and leaping that lashed the waters into foam, and then the crippled monster sank slowly into the ocean depths. The next instant the ship's boat had reached the castaway, and strong arms pulled him aboard, where he sank panting and exhausted across a thwart.