Once more the submarine descended, for the steamer began to show signs of activity. The rhythmic beats of her paddles as she passed overhead gave Huxtable an inspiration. "I'll follow her, by Jove!" he exclaimed. "Ten to one she's going back to Constantinople. It's too good a chance to lose!" CHAPTER XVI A Daring Stroke The Lieutenant-Commander's decision was a sound one. By following the slowly-moving Turkish steamer, maintaining her distance solely by the noise of the latter's paddles, the submarine could keep entirely submerged and yet be led towards a recognized anchorage in the Ottoman navy. It only remained to be seen whether the steamer was making for Constantinople or not. In any case the submarine would be miles nearer her destination by nightfall; but, if the Turkish vessel were bound for the Golden Horn, Huxtable meant to attack at the first opportunity, without waiting for dawn, and trust to the ensuing confusion following the complete surprise to effect his escape. Twenty minutes elapsed. Huxtable's face began to grow long, for the compass course showed that the submarine was being led in a direction S.S.E. Was it possible, he asked himself, that the wretched little paddle-boat was making for Nagara or some of the other Dardanelles forts? "I'll hang on for another ten minutes," he declared. "Then, if the steamer still persists in going in the opposite direction to the one I wish, I'll decline to have any more truck with her." "She's turning," exclaimed Dick. "She's ported her helm." "Good!" ejaculated the Lieutenant-Commander, as the submarine swung round till her bow pointed due north. "Now that is much more reasonable." During the next hour the steamer zigzagged considerably. It was safe to conclude that she was threading her way through the intricate minefield that guarded the southern outlet of the Bosphorus. A long-drawn-out wail upon the syren of the Turkish vessel, followed by four shrill blasts, announced that she was approaching her anchorage. Dearly would Huxtable have liked to bring the periscope of his craft to the surface, but he resolutely resisted the temptation. The unwitting pilot was slowing down; it was time for the submarine to "part company", for the water was shoaling considerably. To follow the steamer farther would result in the British craft being exposed to the danger of being rammed by passing vessels, since the needle of the depth-indicator was already hovering around thirty-five feet. "I might have guessed that she would not be likely to bring up in deep water," remarked the Lieutenant-Commander to Dick, referring to the steamer, the paddle-beats of which were growing fainter and fainter. "It was a chance, of course, but it didn't exactly come off." "At any rate she piloted us in very nicely," said Crosthwaite.