They were, they announced, some of the crew of the armed commerce-raider "Volksdorf," a converted liner that had left the port of Swinemunde two days previously. Hugging the Norwegian coast she had sighted two British patrol ships, and turning southward had shaken off pursuit in hazy weather. Apparently the "Volksdorf's" attempt was-timed to take place simultaneously with the German activity in the North Sea, and by keeping slightly to the northward of the screen of British destroyers she stood a fair chance of gaining the Atlantic. Unfortunately for her she came within easy torpedo range of a U-boat, and the pirate, not knowing that she was of the same nationality and utterly indifferent as to whether she destroyed enemy or neutral ships without warning, promptly discharged a torpedo. The missile struck home, causing a second explosion, as the after magazine of the raider blew up, causing the ship to sink in less than thirty seconds. Billy went on deck to find the "Audax" still cruising about in the hope of finding more survivors, but without success. Making his way to the bridge he informed Aubyn of his discovery. "That's great," declared the youthful skipper. "Fritz committing frightfulness upon his own pals requires some beating. It must have been a strafed U-boat, since I know for a dead cert that none of our submarines are taking part in the present operations. Keeping Middle Watch, Mr. Barcroft? I'd turn in while I had the chance, if I were you. We're in touch with the 'Hippodrome.' Picked up a wireless call not five minutes ago. We'll put you on board before many hours, I dare say, but we don't want to hand you over looking like a sleepy owl; so down below you go." "Thanks, sir, I will," replied the flight-sub, who after the heated atmosphere of the stoke-hold was feeling the cold acutely. And carrying out the genial lieutenant-commander's advice Billy went below, pulled off his sea-boots, divested himself of his oil skins, or, rather, those of the engineer-sub who had insisted on lending them, and flopped into his bunk. He was dimly conscious of thrusting his back hard against the partition, gripping the edge of the bunk with both hands and drawing up his knees to wedge himself in--matters of precaution owing to the erratic motion of the destroyer--and in ten seconds he was in a sound, dreamless slumber. CHAPTER XVIII AN OCEAN DUEL "ACTION Stations!" Billy Barcroft leapt from his bunk, labouring under the delusion that he had turned in only a few minutes before. The deadlights screwed to the brass rims of the scuttles and the electric lights in the wardroom gave him the impression that it was still night, and it was not until he scrambled on deck that he was aware that grey dawn was breaking.