He waved a cheery good-by as the small boat pulled away. "And hurry back," he called. The destroyer commander nodded an emphatic assent. * * * * * On board the _Nagasaki Maru_, Thorpe directed the carpenter and his helpers in the work he wanted done. The man seemed to know instinctively where to put his hands on needed supplies, and the result was a virtual cage of strong oak bars enclosing the wireless room, and braces of oak to bar the single door. Thorpe was not assuming any bravado in his feeling of safety, but he was doing what he had done in many other tight corners, and he prepared his defences in advance. These included weapons of offense as well. As the boat with the destroyer's men pulled back to the _Bennington_, he placed in easy reach in a corner of the room a heavy calibered rifle he had taken from his belongings. And, still, with all his feeling of security, there was a strange depression fell upon him when the _Bennington's_ narrow hull was small upon the horizon, and then that, too, was gone and only the heaving swells and the wallowing hulk were his companions. Only these? He shivered slightly as he thought of that unseen watcher with the devil-eyes whose presence Captain Wilkins had felt--and his men, and the poor terrified ape! He deliberately put from his mind the thought of this; no use to start the day with morbid fears. He went below to examine the cabins. But he carried the heavy elephant gun with him wherever he went. * * * * * Below decks the signs of the marauder were everywhere, yet there was little to be learned. The slimy trails dried quickly and vanished, but not before Thorpe had traced them to the uttermost depths of the ship. There was not a nook or corner that had gone unsearched in the horrible quest for human food. And one thing impressed itself forcibly upon the man's mind. He found a lantern, and he used it of necessity in his explorations, but this thing had gone through the dark and with unerring certainty had found its way to every victim. "Can it see in the dark?" Thorpe questioned. "Or...." He visioned dimly some denizen of the vast depths, living beyond the limits of the sun's penetration, far in the abysmal darkness where its only light must be self-made. But his mind failed in the attempt to picture what manner of horror this thing might be. Even in the hold its evil traces were found. There were tiers of metal drums that still shone wet in his lantern's light. Calcium carbide--for making acetylene, he supposed--marked "Made in U.S.A." The _Nagasaki_ must have been westward bound. * * * * * He went, after an hour or so, to the wireless room, and only when he relaxed in the safety of his improvised fortress did he realize how tense had been every nerve and muscle through his long search. He tried the wireless and got an instant response from the destroyer.