The German, he soon discovered, was not a strong swimmer, but with a vague idea that he was rightfully his prisoner and must not be allowed to escape, Lawless still retained his hold on the fellow's jacket. He soon found that his efforts to keep afloat and assist the other to do the same were taxing his strength to the utmost. Had he abandoned the German to his fate, the Lieutenant would have stood an infinitely better chance, but such a thought never entered his mind even when he began to realise that his strength was almost spent. The patrol boat and the destroyer had disappeared from view, and not even the searchlight was visible, from which Lawless deduced that he and his companion must have been carried astern in a very strong current, which still further minimised their chances of being picked up. At last, when it appeared hopeless to struggle any longer and he had almost resigned himself to his fate, Lawless thought he heard a harsh, gutteral voice hailing him through the darkness. With his last remaining strength he struck out in the direction from which the voice had seemed to come, and a moment later he and his companion were dragged out of the water and over a curved, slippery surface. "_Gott im Himmel!_" exclaimed someone, and Lawless, raising his head, found himself sprawling upon the platform of a large submarine--the same one, he felt sure, which he had recently attempted to sink. Then the man who had given vent to the ejaculation, asked him something in German. "Don't understand your lingo," answered the Lieutenant, dragging himself into a sitting posture and observing that his questioner was a tall man clad in oilskins and sea-boots. "Who are you?" demanded the other, this time in fairly good English. "Lieutenant-Commander Lawless of the British destroyer _Knat_. Who are you?" "Commander Carl von Ranheim of the German Navy," answered the man, and added, somewhat unnecessarily, "you are my prisoner." Lawless, now somewhat recovered, gripped a handrail and dragged himself upon his feet. Two sailors, he observed, were assisting the man for whom he had risked his life through the conning tower hatch. Then, looking over his shoulder, he saw the distant beam of the _Knat's_ searchlight still focussed upon the patrol boat; evidently no one had seen him fall overboard nor had he yet been missed. "Well," he remarked turning to the Commander of the submarine, "what are you going to do with me?" "I have a good mind to send you back where you came from," answered the German officer, jerking his head in the direction of the water. "As a reward for saving one of your men, I suppose," replied Lawless. "Well, as you seem to be afraid of even one Englishman, perhaps it is the best thing you can do." "Afraid!" repeated the other. "_Ach!_ but suppose I take you down below you learn our secrets, eh?" "We've captured so many of your boats that I don't think there are many secrets left for us to learn."