It was remarkable that, though the train was rather crowded, Mr. Dunn and the elderly gentleman, with so insatiable an appetite for details, had this particular first-class compartment to themselves all the way, with the trifling exception hereafter to be noted. There might almost have been an understanding between the railway people and the elderly gentleman--perhaps there was, perhaps also he saw and remarked Mr. Dunn's moves more clearly than he appeared to see and remark them; for when Mr. Dunn (they were then three-quarters of an hour from Liverpool) took a crumpled packet of letters out of his pocket, though the elderly gentleman interposed a newspaper directly between his own face and that of Mr. Dunn's, he slid his hand gently into the pocket of his heavy overcoat, and at the same moment handled something metallic which lay within it. Mr. Dunn pored over these letters with an absorbed attention, which could not have been greater had he been in absolute solitude. He compared their dates, he counted them, he carefully rearranged them, each in its respective former position in the packet, and when he had read and re-read them, he tied them up again and replaced them in an inner pocket. During all this time his companion kept his hand upon the something metallic in the pocket of his rough greatcoat, and when Mr. Dunn, apparently yielding to a momentary temptation to tear up the letters and strew them by the roadside, made a slight motion towards letting down the window next him, he almost instantly withdrew his hand, the barrier of the newspaper was withdrawn for a second, and the usually inexpressive face of the elderly gentleman was set in a very stern purpose indeed. Nothing came, however, of the temptation. Mr. Dunn replaced the letters; his companion reinterposed the barrier; and the train glided smoothly on but another quarter of an hour, during which Mr. Dunn subsided from his restless into his depressed alternative, and occasionally took out a photographic likeness of a woman, at which he gazed moodily. Just as the train was running into Lime-street station its speed slackened, it stopped in an instant, and a man stepped with wonderful swiftness into the compartment hitherto occupied only by Mr. Dunn and the persistent reader. Mr. Dunn slipped the photograph at which he was looking into his breast-pocket, and glanced round surprised, but the elderly gentleman, with a satisfied wink at the new arrival, stuffed his newspaper under the back of the cushion, and bending over and approaching Mr. Dunn, laid his hand on his shoulder.