"Certainly not out of London. He's too much of a Cockney for that. Besides, he's a man who is fond of his wife and child. He's hiding somewhere close at hand, and I shouldn't wonder if the whole thing's a plant between him and his wife. Have you forgotten how she tried to hoodwink us before? I'll go to the shop to-morrow and see if I can't frighten the truth out of her. Meanwhile, you'd better put the Camden Town police on to watching the shop. If he's hiding in London he's bound to visit his wife sooner or later, or she'll visit him, so we ought not to have much difficulty in getting on to his tracks again." Rolfe departed, to do his chief's bidding, a little crestfallen. He was at first inclined to think that he had made a bit of a fool of himself in his desire to prove to Inspector Chippenfield that he had been hoodwinked by Hill into arresting Birchill. But that night, as he sat in his bedroom smoking a quiet pipe, and reviewing this latest phase of the puzzling case, the earlier doubts which had assailed him on first learning of Hill's flight recurred to him with increasing force. If Hill were innocent he would have been more likely to seek police protection before flight. Hill's flight was hardly the action of an innocent man. It pointed more to a guilty fear of his own skin, now that the man he had accused of the murder was free to seek vengeance. Chippenfield's theory seemed plausible enough at first sight, but Rolfe now recalled that he knew nothing of the missing letters and Hill's midnight visit to Riversbrook to recover them. Rolfe had concealed that episode from his superior officer because he lacked the courage to reveal to him how he had been hoodwinked by Mrs. Holymead's fainting fit the morning he was conducting his official inquiry at Riversbrook into the murder. "It's an infernally baffling case," muttered Rolfe, refilling his pipe from a tin of tobacco on the mantelpiece, and walking up and down the cheap lodging-house drugget with rapid strides. "If Birchill is not the murderer who is? Is it Hill?" He lit his pipe, closed the window, opened his pocket-book and sat down to peruse the notes he had taken during his investigation of Sir Horace Fewbanks's murder. He read and re-read them, earnestly searching for a fresh clue in the pencilled pages. After spending some time in this occupation he took a clean sheet of paper and a pencil, and copied afresh the following entries from his notebook: August 19. Went Riversbrook. Saw Sir H.F.'s body. Discovered fragment of lady's handkerchief clenched in right hand. August 22. Made inquiries handkerchief. Unable find where purchased.