Now out of the threatening thunder sounded a single individual note, the rapid beating of a horse's feet--some horse that was bearing a desperate rider ahead of the stampede but powerless to avoid it. Instantly Larkin saw the picture of the yawning precipice toward which the frantic rider was hurrying at breakneck speed. He raised his revolver and fired into the air. The signal was instantly acted on, for in another moment a lathering, heaving pony dashed up to them, and the rider leaped to the ground. "Oh, what shall I do? Hello! Who are you?" cried a female voice, and Larkin's heart leaped as though it had turned over in its place. "Juliet!" he cried, seizing the girl with one arm and drawing her close. "Bud!" For an instant she clung to him. "Lead the horses together and shoot them!" he ordered, although the others could scarcely hear him. Every instant was priceless now, for dimly at the edge of their vision the front wave of the living, leaping tide could be seen. Larkin swung the girl's horse alongside Pinte, and without a thought or a pang shot them both. They fell one on top of the other. Then the stranger in the mask led his animal in front of the two that had fallen and put a bullet through its brain. All now leaped behind this still throbbing barricade. "Got a gun, Julie?" demanded Bud. "Yes." "Give it to me and load mine from your belt." They exchanged weapons and the girl with practiced hand slipped the cartridges into their chambers. The unknown had drawn two guns from some place in his equipment, and now the three peered over their shelter. The advance line of animals was scarcely twenty-five yards away, and, with a clutch of horror at his heart, Bud recognized that they were not cattle as he had supposed, but sheep--his own two thousand. In the instant that remained he remembered the shots and shouting of a quarter-hour before, and realized that the animals had been stampeded deliberately. "Let 'er go," he screamed above the tumult, "and yell like blazes!" On the word yellow fire streamed out from the four guns and, accompanying it, a perfect bedlam of shrieks and cries. The sheep were now upon them, and the hail of bullets dropped some in their headlong career, piling them up against the horses and adding to the barricade. But it could not stop all, and a stream of the animals made its way over the bodies up to the very mouths of the spitting guns. Now others stumbled and fell, to be instantly engulfed by the swirling flood behind; small, sharp feet were caught between the limbs of the struggling mass that eddied about the dead horses. Still the yellow fire stabbed out into the faces of the middlers--for now the leaders were already piling up mangled and dying in the rocky river-bed--but, past each side of this island of expiring creatures, thundered a vast, heaving stream, turbulent, silent, irrevocable.