During that day they made considerable progress, and the first camp of the new trail was pitched on a ridge close to the river. Here the horses were put out to graze, and the boats drawn up on the shore, though a guard was constantly kept to insure against treachery. Despite the apparent friendship shown by many of the Indian tribes they encountered on their long journey of thousands of miles, the two captains never fully put their trust in the red men. They believed them as a rule to be treacherous, and unable to resist pilfering if the opportunity offered. Especially was this true when the coveted object was a horse or a "stick that spat fire," as the wonderful "shooting-irons" of the explorers were generally called. Several days passed with nothing to break the monotony of the journey. Of course they often met with minor difficulties, but these were speedily overcome by a display of that generalship which had so far made the trip a success. All this while the boys had not forgotten about the spy in the camp. Without appearing to do so, they kept a watch upon the three men upon whom suspicion had fallen. Had any one of them offered to leave camp after nightfall, he would have been trailed by Dick and Roger, bent on learning what could be the object of his wandering, and whether he had an appointment with François Lascelles, the Indian trader. But, as the days drifted along, and nothing happened, they began to cherish hopes that perhaps the accident to their canoe had been rather an act of vandalism and malice than part of a deep plan to bring about their death. A week after leaving the winter camp the party found itself on the border of a wide plain. Dick and Roger were mounted and were on a slight elevation down which they expected to pass to the level ground near the river, and await the coming of the boats. From here they could see for a considerable distance around. "Look at the herds of buffaloes feeding here and there, Dick!" exclaimed Roger, whose hunting instincts were easily aroused. "It strikes me we heard Captain Clark say the fresh meat was getting low again. What do you say to trying to knock over one or two of those fine fellows?" "We would have to go a considerable distance to do it, then," the other told him, "and leave our horses in the bargain, because they are not used to approaching such fierce-looking animals as buffalo bulls." "But we might be lucky enough to get one or two yearlings," persisted Roger, who dearly loved the excitement of the hunt, as well as the taste of the well-cooked meat when meal time came. "I think we could manage to load our animals down with the spoils, and easily reach the place where our friends mean to camp for the night."