“Three points off the port bow, sir,” answered Joe; “about four miles, I think.”

“Good!” cried the captain. “Hold your course”—this to the man at the wheel.

He climbed into the mizzen rigging with Joe, and gazed through his glass in the direction indicated. A shade of disappointment came into his face.

“It’s an old bull humpback,” he said, “and I don’t believe we can get near him, but you may see that the first and second boats are in readiness, Mr. Jones.”

“Ay, ay, sir,” answered that man of brevity, using three words in the excitement of the moment; but there had been no need to give the order, for he had several of the crew busy doing just that very thing already. All had been keen in the hope that it would be a sperm whale.

Harry climbed into the rigging too, and as the ship drew toward the spot, he plainly saw an occasional puff as the monster breathed and sent a little cloud of vapor into the air. Steadily they approached the lazy leviathan, and by and by Harry could see his black head and hump, yet still the vessel kept her course, and the order to lower was not given.

“Hullo!” said the captain. “He’s gallied.”

What that might be Harry was not sure, though he took it to mean excited, for the animal suddenly surged forward, half out of water, swung a half circle on the surface with a great sweep of his mighty flukes, and began to forge through the water in their direction. As he did so, something flashed into the air behind him, and a black figure twenty feet long, shaped somewhat like another whale, seemed literally to turn a somersault from the surface, landing with a thud right on the back of the great humpback. The noise of the blow was plainly heard, though the whale was more than a half mile away. The humpback gave a sort of moaning bellow, and sounded.

“’Vast there with your boats,” cried the captain; “the killer has got ahead of us.”

The orca, or “whale-killer” as the whalers call him, is one of the most powerful and rapacious animals in the world. Himself a whale, he is the only one of the species that lives on other whales, and does not hesitate to attack the largest of them. He grows to a length of thirty feet, and his activity and strength are extraordinary. One of them has been known to take a full-grown dead whale that the whalemen had in tow, grasp it in his tremendous jaws, and carry it to the bottom, in spite of its captors. One does not have to believe an old writer who says that a killer has been seen with a seal under each flipper, one under the dorsal fin, and a third in his mouth. Eschrit, however, is reckoned reliable, and we have his authority that a killer has been captured, from the stomach of which were taken thirteen porpoises and fourteen seals. The killer is shaped much like a whale, has great jaws filled with sharp teeth, and a pointed dorsal fin, with which he is fabled to dive beneath a whale and rip up his belly. He is found in all seas, but is particularly numerous in the North Pacific. In the far north he pursues the beluga or white whale and the walrus. He captures the young walrus in a novel manner. The latter climbs on the back of the mother and the great ivory tusks keep the orca at bay, but he dives beneath the old one and comes up against her with such a blow that the young one falls from the rounded back of its mother, when it is immediately seized and crushed in the great jaws of the rapacious animal.