"I can hear other spouting fountains not far away!" declared Roger. "Sometimes it is like a giant snake hissing, and then again I seem to catch a distant but terrible roaring sound, reminding me of that fierce bear in the cave." "Even if the winter is coming on here, there are plenty of birds still to be met with," Dick remarked, as a flock of cawing crows started up from a tree-top near by, and flew away. "Yes, there are hawks also, and I am sure I saw a pair of great bald-headed eagles soaring away up in the sky, wheeling in circles as they rose. Besides, we have stirred up many of those brush fowl that are so much like our chickens at home, and make such fine eating." "It would be a great place for a hunter or a trapper to spend the winter," Mayhew commented, "if only he could get used to the awful things there are going on in this beautiful section of country. You see, the snow must soon melt where there is so much heat; and that keeps the grass green for the deer and the buffalo." "Hark!" exclaimed Roger, stopping suddenly. His face lighted up with eagerness, and Dick was filled with curiosity. "What did you think you heard?" he asked, presently. "The signal we want to catch more than anything else," came the confident reply. "Not the whistle Jasper Williams taught us to practice, Roger, and which he uses when he wants to communicate with friends?" "That, and nothing else, Dick. I am sure I caught it, coming from somewhere over to the right." "Then why not answer it?" Dick told him. "Do you think it would be wise?" asked the other. "We want to know if Jasper Williams is near by, and that is the best way to find it out. You can give the whistle, Roger, for I have heard you practice it many times." For answer Roger puckered up his lips, and emitted a peculiar little trill. Should any one not familiar with it hear this sound, he would naturally imagine some bird was calling to its mate. All of them stood there, eagerly waiting to discover if Roger's note called forth any response. Before ten seconds had passed there came a faint whistle, very like that which the boy had given. "There, did you hear it, Dick?" gasped Roger, turning a flushed face toward his cousin, while his eyes sparkled joyously. "I heard a sound that might be just such a whistle as Jasper taught us," replied cautious Dick; "but don't build too many castles in the air, Roger, or you may be disappointed. Try again!" Roger was only too willing to do so, and there was an immediate reply this time, that all of them heard plainly. "He's coming this way, I do believe, for that was closer than before. Shall I give him another call?" "Yes, it can do no harm, and we must know the truth, at any rate." When the next answer came back it was beyond all doubt nearer than any that had preceded it.