Lethbridge gave the flash that indicated his comprehension of the communication, and then, with the switch-handle still in his hand, intently watched, through one of the pilot-house windows, the movements of the three. He saw them lower themselves down on to the sand, and immediately begin to climb up the rugged side of the reef. The surface of the rocks was slippery with weed, and their progress was, therefore, painfully slow; but at length they reached a point above and clear of the wreck, and von Schalckenberg then turned and faced the pilot-house, evidently asking for guidance. "Go higher and bear to your right," signalled Lethbridge; and the men resumed their climb. They were now making directly for the spot at which the octopus had disappeared, and a _few_ minutes later they reached a ledge, with the cave immediately in front of them. The professor now again faced round inquiringly, and Lethbridge signalled-- "That is the spot." Von Schalckenberg threw up his arms to indicate that he understood; and then Lethbridge saw the three men stand and confer together for a moment. Then, drawing their daggers and switching on their lights, they all three plunged into the cave and vanished, leaving the solitary watcher in the pilot-house in a state of painful suspense that endured for fully ten minutes. At length, however, the professor and one of the others reappeared, each of them dragging at a long, limp tentacle; and in another moment the huge body of the octopus came into view with the remaining two men pushing it vigorously from behind. As it reached the edge of the ledge the professor and his companion stepped round to assist the other two, and presently the great unwieldy body went rolling limply and lifelessly down the face of the reef until it lay motionless upon the sand. Then the four men made their way carefully down after it, when, having reached the sand, they turned and bent their footsteps in the direction of the _Flying Fish_. CHAPTER TWENTY TWO. THE PIRATE CRUISER.