Driven by spur, whip, and voice, the tired horse tried to leap it. It rose in the air, making a gallant effort, but lacked strength to carry it across, and went falling down, down, into the great gully. Lena Forest screamed as the horse took that plunge. Clayton gripped tightly the rein, caught hold of the horn of the saddle, yelled for the girl to cling to him, and steadied himself for the shock of the fall. The horse struck with stunning force, and rolled over, throwing the girl to one side. Clayton was hurled from the saddle over the horse’s head, where he lay, unconscious and white-faced. Lena Forest scrambled up unhurt, but dazed and frightened. Then she screamed again, as she saw Bruce lying there as if he were dead. And on came the fire, roaring and writhing, shooting up crackling flames that seemed to laugh in glee, as if they realized the terrible predicament of the girl and her brave lover. CHAPTER XXIV. THE SCOUTS’ PURSUIT. Buffalo Bill and Pawnee Bill, or Kulux-Kittibux, as he was known among the Indians, after the departure of Nick Nomad, began a search along the cañon stream. They left their horses behind them, for the ground was too rough for a horse to get over it. The thing for which the eagle eyes of the scout were searching was seen by him at last, when he began to despair of finding anything of the kind. “There it is, Gordon,” he said, pointing. What seemed a foot section of twisted vine rose from the water, and was wound in the most natural manner round the root of a tree. Buffalo Bill scrambled toward it, and soon had his hand on it. “Yes, just as I thought,” he said, and he began to pull on the thing. Soon it lengthened, and a sunken canoe rose into view. It had been sunk cleverly there by its Indian owner; and the painter of time-stained rawhide, twisted round the root in imitation of a vine, the Indian had felt sure could not be distinguished from an actual vine. The canoe was drawn from the water, and the water poured out of it. Then the two friends entered it. Buffalo Bill took up the paddle that had been lashed to the canoe, and turned the bow down the stream. They ran the rapids successfully. Because of the speed with which the current hurried them on, and also because of the cleverness of Crazy Snake, they did not see where he had concealed and sunk the canoe in which he had gone down the stream; but swept on past it, and soon again were in rapids that bore them farther and farther from that spot. Finally they abandoned the canoe, after sinking it and marking the place, and went along the banks of the cañon stream, trying to find the trail of Crazy Snake. “He’s been too much for us,” the scout admitted, when, after long searching on either shore, and for a long distance up and down the river, they were still in the dark. “The rascal was Crazy Snake, I don’t doubt; and he’s one of the cleverest and least crazy of all the Blackfeet.”