Early on the following day Thornton Carey paid another visit to the police authorities, with whom he had already been in communication. As much to their surprise as his own, and their mutual congratulation, he was enabled to lay the case before them with all the detail, explanation, and certainty acquired by the perusal of Mr. Dunn's letter. With the exception of certain inquiries which he had made during his brief absence at Liverpool and his interview with certain magnates of Scotland-yard on the previous day, Thornton Carey had, so far, worked up this case without professional assistance; but he now asked for such assistance in the practical form of a warrant for the arrest of Mr. Dunn. There was no difficulty about the granting of the warrant, but Carey was advised that it would be much better to have it carried into effect at Liverpool, the scene of the murder, and whither it was evident Mr. Dunn was about to transfer himself within a very few days. To this advice Thornton Carey deferred perhaps a little unwillingly; he had a mortal dread that his prey might escape him, that the cunning which had availed the murderer so far might be put forth in a final effort, which would elude all their vigilance. But a little professional reasoning tranquillised his mind on this subject. It would be totally impossible for Mr. Dunn to escape the vigilance of the police at the port of Liverpool; and if he should leave his present lodgings without the knowledge of Thornton Carey and Mrs. Jenkins, the fault would be theirs. The gaoler of the prison to which he would be inevitably transferred before long would not have him in surer watch and ward than the quiet-looking, business-like, and unsuspicious lady and gentleman occupying the dining-room floor. With this assurance, and instructions that he was to communicate with a certain person to whom he was introduced, and who was desired to hold himself at the applicant's disposal, Thornton Carey returned home just in time to see Mr. Dunn, in his usual neat attire and with his accustomed deliberation of step, turn into Piccadilly with the air of a gentleman who had nothing whatever on his mind but the procuring of air and exercise. Two days, which both Thornton Carey and Mrs. Jenkins found exceedingly tedious and hard to dispose of, elapsed, and on the morning of the third, Mrs. Watts, who had made great friends with her lady lodger of the dining-room floor, came to inform her that she was really about to lose Mr. Dunn at last. Yes, it was just like her luck. He was going for good, and the quietest and most accommodating of lodgers would be known no more in Queen-street, Mayfair. Indeed, Mrs. Jenkins sympathised. It was rather sudden, wasn't it? Had Mr. Dunn had any bad news from home, or had he completed all his business in London?