By degrees the Huns, realizing that they were not immediately going on a visit to Davy Jones, began to calm down. A petty officer, making his way aft, flashed his torch upon Alec. The latter, still clad in the dinghy canvas suit, was easily mistaken for one of the crew, for the petty officer, pointing for'ard, gave a curt order. Seton had not the faintest notion of what the Hun said, but the gesture was unmistakable. Entering into the fun of the affair, the Sub, squeezing through a small oval-shaped aperture in one of the transverse bulkheads, found himself in the bow torpedo-room. At that moment, the artificers having renewed the blown-out fuse-wires, the electric lamps were lighted. Alec was alone in the compartment. In front of him were the twin torpedo-tubes, which differed from the British ones in one important detail. Instead of the breech piece being secured by six butterfly nuts, the German method was to employ an intercepted thread cam-action, similar to the breech-block mechanism of a quick-firing gun. Above the tubes were six oiled steel torpedoes, each ready to be "launched home" into the tubes. "By Jove! What an opportunity!" thought Alec, giving a cursory glance to reassure himself that he was alone. "A gorgeous chance to do the dirty on Fritz!" Picking up a heavy adjustable spanner, Seton set to work quickly and deftly. To each of the rudders of the torpedoes he gave a slight and almost imperceptible twist. In the excitement of launching home and firing the deadly missiles, the Hun torpedo men would almost to a certainty overlook the slight but important bend in the delicately adjusted metal fins. "Good enough!" declared Alec. He felt like a schoolboy engaged in ragging an unpopular fellow's study. It was time to make himself scarce before his presence was detected. His luck was in. Without encountering anyone he regained his cell and closed the door. "Now Fritz can use his tin-fish as often as he likes," he thought gleefully. "He's welcome to puzzle his brains to find out why the blessed things won't run true, for it's a dead cert. they won't." It was a matter of three or four hours before the U-boat again rose to the surface. Her batteries were running low. If again obliged to submerge before regaining her base she would be compelled to rest helplessly on the bottom of the sea, since her underwater propulsion powers were almost nil. When the sailor reappeared with Alec's unappetizing meal--black bread, acorn coffee, and sausage of doubtful origin--the German looked suspiciously at the door. "You haf with the lock played tricks," he declared. "Must have been the concussion," said Alec. "It was a nasty shock, wasn't it?" The fellow scowled with sullen anger. "Schweinhund Englander," he muttered. "I go tell der kapitan." He put the food upon the floor and went to the door. Then, half turning, he inquired: "Vot you give me, if I not tell der kapitan?" Seton laughed outright. His sense of humour was tickled.