He kept his eye steadily upon the ugly and wicked warrior, and as he watched for his chance and awaited the word from Boyd all scruples about firing disappeared from his mind. It was that warrior's life or his, and the law of self-preservation controlled. Nearer and yet nearer they came and the time had grown interminable when the hunter suddenly said in a low voice: "Fire!" Young Clarke pulled the trigger with a sure aim. He saw the hideous warrior draw himself into a bunch that sprang convulsively upward, but which, when it fell, lay back, outspread and quiet. Then he fired at a second figure, but he was not sure that he hit. The hunter and the Little Giant were already sending in their third and fourth bullets, with deadly aim, Will was sure, and the Sioux, after one mighty yell, wrenched from them by rage, surprise and fear, were fleeing down the pass under the fierce hail from the repeating rifles. In a half minute all the shadows, save those outlined darkly on the ground, were gone, and there was complete and utter silence, while the light smoke from the rifles drifted about aimlessly, there being no wind. The three did not speak, but slipping in fresh cartridges continued to gaze down the pass. Then Will heard a wild, shrill scream behind him that made him leap a foot from the ground, and that set all his nerves trembling. The next moment he was laughing at himself. One of the horses had neighed in terror at the firing, and there are few things more terrifying than the terrified shriek of a horse. "Maybe you'd better go back and see 'em, Will," said Boyd. "They may need quieting. I've noticed that you've a gentle hand with horses, and that they like you." "And mules too," said the Little Giant. "Mine hev already taken a fancy for young William. But mules are much abused critters. You treat 'em well an' they'll treat you well, which is true of all tame animals." Young Clarke suspected that they were sending him back to steady his own nerves as well as those of the animals after such a fierce encounter, but if so he was glad they had the thought. He was willing enough to go. "Nothing will happen while you're gone," said Boyd cheerfully. "The Sioux, of course, would try to rush us again if they knew you were away, but they won't know it." Will crawled until he came to a curve of the cliff that would hide him from any hidden Indian marksman, and then he rose to his feet, glad that he was able to stand upright. He found the horses and mules walking about uneasily at the ends of their lariats, but a few consoling strokes from him upon their manes quieted all of them, and, if they found comfort in his presence, he also found comfort in theirs. Then he kneeled and drank at the rill, as if he had been parching in a desert for days. CHAPTER V THE WHITE DOME