WITH lusty strokes the two boys urged the boat up-stream. The Indian sat amidship and seemed to be scanning the shore as though deeply interested in everything he saw; though, from what he told Jasper Williams, the locality must have been familiar to him, since he knew all about the fishing to be had in the smaller stream. Now and then the boys exchanged a few words, though as a rule they kept most of their "wind," as Roger called it, for their arduous work. "I wonder what Jasper Williams meant," remarked Roger, after they had gone possibly a full mile. "Of course you mean when he said there was a difference between red and white," Dick suggested. "I was thinking of the same thing myself, and came to the conclusion it must have been Jasper's way of telling us to keep an eye on our dusky pilot here. In plain words, he warned us to look out for our guns." "Which we will certainly be sure to do!" commented Roger. "Though, after all, we may be wronging the poor Indian by our suspicions." "If he never knows it there can be no harm done, don't you see?" Dick told him. Various things about the shore attracted their attention just then, and for the time being they forgot all about the red man, and the warning given by their old frontiersman friend, Jasper Williams. "The farther we go up the river," Dick was saying, "the greater the forests seem to become. From all I've been able to learn, we will pass through many a stretch of wood before we reach the foot of the big mountains." "Yes," added Roger, "and, as the river is getting more and more shallow every day, Captain Lewis seems to believe we must soon abandon our boats, and take to the horses for the rest of the journey." "Look up ahead and on the left, you will see signs of a stream coming into the Missouri. That must be where we are to stop." At that Dick made gestures to the Indian, who, quickly comprehending what was wanted, nodded his head in the affirmative. "Yes, he says that is the place," Roger observed, as he started to put still a little more vim into his strokes with the paddle, so, as Dick was compelled to follow suit, or have the boat headed in toward the shore, their progress increased to a wonderful degree. In good time they reached the mouth of the tributary stream. It was found to be as clear and cold as any one could wish on a warm day. No wonder, Roger thought, the trout loved to frequent its waters, and lie in the deep, dark pools that doubtless existed here and there, though without a guide they could have been found only after much patient searching. Obeying the gestures of the Indian, they made for the shore and left the boat, first making sure that it was pulled well up. Of course, besides their poles and the little box of bait, they carried their faithful guns along with them.