He unlocked a drawer and pulled out two bulky packets of documents, neatly tied with string. Entwistle had a distaste for red tape, both metaphorically and literally. For the best part of an hour he busied himself with the various and for the most part faulty clues, endeavouring from the tangled skein to weave a thread of conclusive facts. The offer of the one hundred pounds reward had had its disadvantages. Amateur detectives and others attracted by the offer had seen "Captain Fennelburt" in a dozen or more different places at approximately the same time. Copies of letters from these individuals had been included in the dossier sent to Entwistle from Scotland Yard. One was from a farmer at Penzance, who was certain that he saw the wanted man making for Poldene Air Station. Another emanated from a fisherman at Wick, who stated that an R.A.F. officer answering to the description of Captain Fennelburt stopped him and inquired the way to Loch Thrumster Flying School. Yet another correspondent, hailing from Ramsgate, reported that the spy was boarding at a small house near Pegwell Bay. "Even in these days of high speed in aviation," thought Entwistle, "there are limits. We have yet to find conclusive evidence of a man starting from Wick, say, at 9 A.M. and finishing at Penzance at 11 A.M.--650 miles in two hours. And when he stops on the way to partake of refreshments at Ramsgate--involving a detour of another couple of hundred miles--the imagination is stretched beyond breaking-point. I'm afraid these worthy people are following the red-herring trail. The R.A.F. uniform has put them on a false scent. Now, if I were in Captain Fennelburt's position--without, presumably, a change of clothes--in a fairly distinctive uniform, what would I do?" His meditations were interrupted by the entrance of a maid with a telegram. "No answer," said Entwistle briefly. The wire was from the stationmaster at Carlisle. No R.A.F. railway warrant bearing the number E99109 had been given up at Carlisle. "That is quite what I expected," thought the Secret Service agent. "The warrant was a forged one, and Carlisle was a bit of bluff. He's probably lying low in Edinburgh. Suppose it's not much use trying to pick up the trail there now? Yet--H'm! I'll risk it." He took an up-to-date time-table from a shelf. Experience had taught him to be particularly careful as far as the times of departure of trains were concerned. "H'm this will do. Arrive Waverley Station at so-and-so. Yes, that will do." In ten minutes Entwistle had made all necessary preparations, and with a small hand-bag as his total luggage was walking briskly to the station.