Then, to the surprise of everyone, the doctor waked up and knew just where he wanted to go. He displayed an unexpected familiarity with the general topography of the hills. It puzzled Billy. And, to the vaster astonishment of both his _confrères_, Jim suddenly announced, with quite unwonted volubility, that he had been intending all along to start in prospecting at the end of this trip, and that here he meant to quit scouting and leave the society of his brothers in arms--unless, of course, he added, as a doubtful afterthought, they wanted to join him. They profanely replied that they did not. Most of the men pushed on immediately to Rockerville, whither a majority of the former inhabitants of Frenchman's Creek had already emigrated. Alfred and Billy decided to get over in the Limestone for a "big hunt" before returning East. Prue said good-by to them with real feeling, and most of them threw out their chests and were very gruff and rude because they were sorry to leave. Prue understood. They were kind-hearted men, after all, these rough pioneers. Billy remembered for almost two years how she looked when she said that, which was extraordinary for Billy. He had led so varied a life as pony-express rider, stage-driver, scout, Indian, bronco-buster, hunter, and trapper, that he had little room in his memory for anything short of bloodshed or a triumph for himself. Finally, after all the rest had gone, Jim and the doctor made the mutually delightful discovery that they had selected the same locality, the one for his prospecting, the other for his scientific investigations. So the doctor simply left his outfit in Jim's wagon, and they all went up together. The little scientist was as excited as a child. To him the country was as a document--a document which he had studied thoroughly in the pocket editions. He now had it before him in the original manuscript, open and unabridged. And indeed, even to an ordinary observer, the Black Hills are a strange series of formations. They run north and south at the westernmost edge of the northern prairie, and are, altogether, about as large as the State of Vermont. Unlike other ranges, they possess no one ridge that serves as a backbone to the system. The separate peaks rise tumultuously, like the rip of seas in a tideway, without connection, solitary, sombre. Between them lie deep gorges, or broad stretches of grass-park, which dip away and away, until one catches the breath at the grand free sweep of them. Huge castellated dikes crop up from the ridge-tops like ramparts. Others rise parallel in the softest verdure, guarding between their perpendicular sides streets as narrow and clean-cut as the alleys of a city of skyscrapers.