"'Tis like this, sir," explained his companion with the utmost gravity. "Her captain is living on board, an' 'e's got a bald 'ead. When it rains they rigs up an awning to keep the drops off 'is pate, 'cause 'e gets awfully up the pole an' leads the crew a regular dog's life if he's upset by gettin' 'is 'ead wet." "I perceive you are a humorist," remarked von Preussen drily. "Didn't know it, sir," rejoined the man. "My mates usually call me 'Mouldy Bill.' But hangin' around 'ere won't find what you're lookin' for, sir, so let's make a move." It was an application of "official reticence and reserve" on the part of this minor servant of the Admiralty. He knew perfectly well that the tramp was in reality a Q-boat, and that under those canvas awnings lay hidden a collection of mysterious "gadgets," for a detailed description of which the authorities at Berlin would give a high sum in gold. To linger would arouse suspicion, so reluctantly the spy followed his guide on what he knew to be a vain quest for craft that were no longer at Auldhaig. "Why not try the Kite and Balloon Section of the R.A.F.?" suggested an official. "The depot is just across the harbour. I'll let you have a boat." Von Preussen debated before replying. The offer was a tempting one, for not only would he get a chance of having a closer view of various warships in the stream, but there was no telling what information he might pick up at the depot. On the other hand, he didn't want to be asked awkward questions by men wearing the same uniform as himself. He knew, however, that it was no exception to detail perfectly incompetent officers on inspection duties. He had heard of a case of one who hardly knew one end of a boat from another who was sent on a 700-mile journey to report upon some rowing-boats about to be purchased for a station in the south of England. "Thanks," he replied. "I may even yet get on the track of those elusive X-barges." Twenty minutes later von Preussen was seated in the stern-sheets of a harbour service duty boat. To his guarded inquiries of the coxwain as to the names of the vessels lying at the buoys, he received an equally guarded answer: "Dunno, sir they comes and goes all hours of the day and night, an' not havin' no names painted on 'em, and bein' all disguised-like, I can't tell no more'n a nooborn baby." The duty-boat rubbed gently alongside the stone steps of the jetty. Von Preussen stepped ashore, returned the sentry's salute, and inquired the way to the adjutant's office. "X-barges?" queried the adjutant. "None this side. We used to borrow 'em from the dockyard, but we transferred most of our observation balloons more than a month ago, and so we don't require the barges. But now you are here, come and have lunch. It's close on one-thirty." "Many fellows here?" asked the spy, as he accompanied his host across the wide parade-ground to a long wooden hut used as the mess.