"Well, sir," explained Sparrowhawk, "he came ashore from the German submarine at night, while Pyecroft was lying helpless on the beach. Four men brought him ashore in a collapsible boat, and he vanished inland, still rigged out in R.A.F. uniform. Pyecroft can swear definitely on that point." "And Sheerness Air Station has disclaimed all knowledge of him," remarked the C.O. "Why the deuce the Air Ministry cannot be more particular in posting the movements of officers passes my understanding! Can you give a fairly accurate description of Captain--er--Fennelburt?" "I think so, sir; he was at the mess to lunch, and I saw a good deal of him." "Good," ejaculated Colonel Greyhouse. "Send a report to 'Area,' and at the same time to Scotland Yard. The police will then take the matter up. You might also inform the Naval and Military Authorities. If we don't lay the fellow by the heels within the next twelve hours I'll eat my hat." A vow that, taking into consideration the copious gold leaves that adorned the peak, was an exceedingly rash one, unless Greyhouse had the digestion of an ostrich. CHAPTER XVI COVERING HIS TRACKS FOR the second time within forty-eight hours Karl von Preussen tramped the deserted road leading to Nedderburn Junction railway station. On the previous occasion he called himself Captain George Fennelburt; on the second he had assumed the name of Ronald Broadstone. He travelled light, but in place of his khaki, leather-reinforced haversack he carried a small portmanteau, which, owing to unforeseen circumstances, was practically empty. He decided that at the first favourable opportunity he would replenish a portion of his kit and replace that lying at the Auldhaig Hotel. But in the portmanteau was an automatic pistol of British manufacture. Its possession showed economy and discrimination in small details. Since it had been acquired from a battlefield, it had cost von Preussen nothing; and being of British make it was in keeping with the spy's rôle as an officer of the Royal Air Force. He walked quickly and unhesitatingly along the bleak, unfrequented road. Delay meant the great possibility of missing the night train and a consequent detention at Nedderburn, which was too close to Auldhaig to be pleasant. He had good reasons for steering clear of Auldhaig "for the rest of the duration." The place had been a "wash-out," and since von Preussen was of a superstitious nature he always avoided scenes of previous failures. Beyond meeting a belated shepherd, who greeted the spy in an unknown Highland dialect, von Preussen arrived at Nedderburn without encountering anyone. The station had just been lit up, two feeble paraffin lamps providing the necessary illumination for the safety of passengers. Peeping through the high wooden palisade, von Preussen took stock of the people on the up-platform.