Roger was even instructed to remember this in case he ever had another opportunity to procure fresh mutton; and, having already secured the desired horns, he readily promised to keep the advice in mind. It happened, however, that another chance at the mountain sheep never came his way. In two more days the expedition had crossed the great divide, and found that, when the sun went down, they could see far away toward a level horizon. Remembering all the dismal tales related by the superstitious Indians of sandy wastes where only a sparse vegetation grew, the men began to feel a new anxiety. Just how far away the goal they were seeking still lay not even the astute leader, Captain Lewis, could more than guess. It might be a hundred miles, and perhaps many times that; for they had by this time reached a point where they had nothing to depend on, save the vague stories told by wandering Indians whom they happened to meet. Some of these, however, mentioned a great body of salty water, the end of which no human eye could reach, as lying far beyond the hot deserts. There were also rivers spoken of, where the great fish swarmed in countless millions, like the stars in the Milky Way overhead, or the sands on the shore of the "Big Water." Roger hugged these stories to his heart. He fancied that, once they struck that river of the mighty game fish, he would be in his glory; for, if there was one thing above all others Roger loved to do, it was to fish. The time finally came when they found themselves on the verge of the desert of which they had heard so much. There could be no such thing done as pass around the sandy waste, and their only course was to head straight into the setting sun. At the time they had with them an Indian whom Captain Lewis had succored on the way. The fellow had fallen and injured his leg so that he walked with the greatest difficulty, limping badly. He had lost his bow, and being unable to provide himself with food, and far from his home, he stood a good chance of starving to death. They had fed him and looked after his injuries. The Indian professed to be very grateful for such help, and for several days had clung to the expedition, though able by then to walk fairly well. He had assured them, through signs mostly, that he could serve them as guide across the hot waste of sand, as he had himself crossed it on many occasions. Captain Lewis considered this a fair return for what he had done. Dick, however, did not altogether like the Indian's looks. He thought he had a crafty way of watching everything, and that his admiration for some of the horses might lead him to attempting a theft, unless he were diligently watched. Still, since the captain seemed to trust him, Dick did not think it was his duty to say anything. It might look as though he were inclined to be bold. At the same time, he made up his mind that, whenever it was possible, he would keep an eye on the red man.