"Well," said Frank, "I can't see that it will do any harm to tell you. We extract air from the water." The German commander leaned back in his chair and looked at the lad in amazement. "Extract air from the water, eh?" he said slowly. "Do you mean to tell me that England has solved that problem?" "She has, sir," replied Frank quietly. The German was silent for a long time before he said: "Then I must say that Germany has a hard job on her hands." Frank was silent and the captain continued: "And how many such vessels have you in operation?" Frank hesitated. "Well, only a few right now," he said at last. "But many more are in the process of construction." "And are you familiar with the operations of such a vessel, and of the method used?" "To a certain extent, yes." "But I do not suppose you could be prevailed upon to divulge the secret?" "I could not," replied Frank quietly. "Good! I thought not. Well, it's too bad that we were not the first to discover the secret; but you will find that we do not whine, nor will we seek to obtain the secret by unfair means." "I am sure of it, sir," replied Frank. "Now," said the German commander, "I must decide what I am going to do with you. I suppose that you know you will be held until the end of the war?" Frank nodded as he replied: "I should suppose so." "I shall have you sent ashore in the morning and turned over to the military authorities. The chances are that you will be taken to Berlin. Of that I am not sure, however." "One place will do as well as another, I suppose." "I'm glad you are cheerful about it," laughed the captain, "and as mess hour is approaching I shall be glad to have you dine with me." "I shall be pleased to do so, sir." "By the way," said the German, "what is the speed of this remarkable submarine of yours?" "I wouldn't like to say," replied Frank, "but I can say that it is fully as great as that of your fastest battleship." The German puckered his lips in a long expressive whistle. "Well," he said, "it's too bad for us. Now, if you care to wash up I shall have you shown to your temporary quarters." It was a pleasant meal to which the lad sat down that evening, and he enjoyed himself immensely. He found the German officers a likeable lot and was treated more as a guest than as a prisoner. It was while at table that he learned that German submarines had been sent down in search of the British vessel, and that each battleship was being guarded by an under-the-sea fighter so that no surprise attack by the D-16 might be made. At a late hour the lad retired and slept the sleep of the exhausted. He was up bright and early the following morning, and after breakfast took his place in the ship's launch, which immediately headed toward the shore. The captain bade him a pleasant good-bye, and added: "If I get to Berlin I shall look you up." "I'm not there yet," said Frank, but in his heart he was pretty sure that it was only a question of hours until he would be.