He continued on to Wellington, skirmishing along the line, and observing the faces of the postmasters; but these studies in physiognomy threw no light on the mystery, as the officials of the department on the route, though far removed from central supervision, seemed to be all that their affectionate uncle at Washington could wish. On the return trip the detective was equally observant and equally perplexed. At that season the stage stopped for the night at Hannibal; but there, likewise, the postmaster shared the honest looks that seemed to prevail through eastern Dakota. Proceeding on, the passengers dined at Raven's Nest, where one Michael Mahoney, Sr., kept a small store and the post-office, running also--with the aid of a young son and a son-in-law--a farm. The store was managed by Michael Mahoney, Jr., a married son, who happened to be absent both when the special agent went up and when he returned. The face of the old man indicated that he was vicious, ignorant, and unscrupulous; but clearly he was not sharp enough to execute nice work like that under investigation. With the exception of a general knowledge of the offices, the special agent returned but little wiser for the trip, and concluded, as the best that could be done under the circumstances, to allow the bird to flutter a little longer before renewing the hunt. Meanwhile the thief grew more reckless, and the papers that came to Mr. Furay, though covering a fraction only of the depredations, located the thief on the lower end of the route, within fifty miles of the terminus. During the summer one or two other agents took up the matter cursorily, but made no discoveries. In the meantime Mr. Furay was kept too busily occupied with a succession of important cases in Nebraska to give much thought to the outlying territory of Dakota. At length, in September, he went carefully over the papers that had accumulated during his late prolonged absences, and soon knew exactly where to look for the chap who had so long plundered the public with impunity. For some time Chicago had been closing registered package envelopes with wax, which, on this route at least, effectually secured them against molestation. Imitating the example, Camden, Dakota, began to do the same; but, having no seal suitable for the purpose, improvised a substitute by using the flat surface of a rasp. Camden placed the wax near each end of the envelope, which materially interfered with the game of the thief, because it was just here that he operated. Evidently piqued that a rural postmaster should presume to outwit him, he studied hard to devise some means for opening these particular packages without leaving such traces of his handiwork as would attract the notice of other officials through whose hands they might subsequently pass. The effort was crowned with a measurable degree of success, for Mr. Furay, at the general overhauling referred to, was the first to discover that the seal had been tampered with.