"The youngster has good cause for concern," soliloquised Fuller. "This old tub wouldn't stand a cat's chance if anything went wrong. She's one of those craft that's made by the fathom and cut off where required, I should imagine. Never saw such rough work in all my life. And no sign of air-locks or any lifesaving devices. I suppose such details don't worry the German Admiralty. Those leaking joints remind me of the old Tower Hill subway. A coat of whitewash and gas jets instead of the electric light would make the illusion complete."

His reveries were interrupted by a sliding door in the after bulkhead being opened. The German seamen sprang to their feet and stood rigidly at attention as a young, heavily-built unter-leutnant appeared and beckoned the prisoners to follow him.

Stepping over the sill of the watertight door Fuller and his companion found themselves in the officers' quarters—a compartment extending the whole width of the vessel, and separated from the engine-room by another bulkhead. The cabin was plainly furnished but with a certain degree of comfort. On either side were two curtained bunks. A swinging table occupied the centre of the floor, with four revolving arm-chairs, the feet of which were clamped to prevent them being capsized in heavy weather. Against the after bulkhead were two bookshelves and a folding wash-basin, while between them was a ladder communicating with the conning-tower. On the for'ard bulkhead were voice-tubes and telephones for conveying orders to various parts of the vessel, also gauges of various descriptions similar to those in the conning-tower, so that the commander, when not on duty, could know what was going on without having to hail the navigating officer. In the arched ceiling was an illuminated tell-tale compass.

"North 88 east," said Fuller to himself, as he read the magnetic bearing. "She's making for the Elbe or the Weser, I'll swear."

"There is no need for you to trouble about the course," said a broad-shouldered officer dressed in the uniform of a kapitan- leutnant of the Imperial German Navy. "That is our affair. Now, tell me—no lies, mind—what is your name?"

Fuller met the penetrating eye of his examiner without flinching, yet he realised he was "up against" a sharp Teuton, who, by his command of the English language, had evidently an intimate and first-hand knowledge of his enemy's country.

It was, Fuller knew, futile to dissemble. The fact that Kirkwood and he were missing would be revealed by the British Admiralty casualty list. Neither would any good purpose be attained by refusing to reply to any questions that could be answered without giving useful information to the Huns.

"John Fuller, flight-lieutenant, H.M.S. 'Hippodrome,'" he replied promptly.

"So? Then let me offer my congratulations at you again becoming the guest of the Imperial German Government," rejoined the kapitan-leutnant sarcastically. "I do not think you will escape again, Mr. Fuller. Since Sylt was too easy a place of captivity you will most a certainly be sent inland when we arrive in harbour—somewhere a very long way from the convenient neutral port of Esbjerg. Now, I suppose it is of no use asking you under what circumstances you were brought down?"

"Engine failure owing to the petrol tank being perforated."