"Lieutenant, quick! for God's sake! They're coming!" cried the voice of the German soldier at the wall, and wrenching his wrist from the clasp of the dying man, Blakely sprang recklessly to his feet and to the mouth of the cave just as Stern's carbine broke the stillness with resounding roar. Half a dozen rifles barked their instant echo among the rocks. From up the hillside rose a yell of savage hate and another of warning. Then from behind their curtaining rocks half a dozen dusky forms, their dirty white breechclouts streaming behind them, sprang suddenly into view and darted, with goatlike ease and agility, zigzagging up the eastward wall. It was a foolish thing to do, but Blakely followed with a wasted shot, aimed one handed from the shoulder, before he could regain command of his judgment. In thirty seconds the cliff was as bare of Apaches as but the moment before it had been dotted. Something, in the moment when their savage plans and triumph seemed secure, had happened to alarm the entire party. With warning shouts and signals they were scurrying out of the deep ravine, scattering, apparently, northward. But even as they fled to higher ground there was order and method in their retreat. While several of their number clambered up the steep, an equal number lurked in their covert, and Blakely's single shot was answered instantly by half a dozen, the bullets striking and splashing on the rocks, the arrows bounding or glancing furiously. Stern ducked within, out of the storm. Blakely, flattening like hunted squirrel close to the parapet, flung down his empty carbine and strove to reach another, lying loaded at the southward loophole, and at the outstretched hand there whizzed an arrow from aloft whose guiding feather fairly seared the skin, so close came the barbed messenger. Then up the height rang out a shrill cry, some word of command in a voice that had a familiar tang to it, and that was almost instantly obeyed, for, under cover of sharp, well-aimed fire from aloft, from the shelter of projecting rock or stranded bowlder, again there leaped into sight a few scattered, sinewy forms that rushed in bewildering zigzag up the steep, until safe beyond their supports, when they, too, vanished, and again the cliff stood barren of Apache foemen as the level of the garrison parade. It was science in savage warfare against which the drill book of the cavalry taught no method whatsoever. Another minute and even the shots had ceased. One glimpse more had Blakely of dingy, trailing breechclouts, fluttering in the breeze now stirring the fringing pines and cedars, and all that was left of the late besiegers came clattering down the rocks in the shape of an Indian shield. Stern would have scrambled out to nab it, but was ordered down. "Back, you idiot, or they'll have you next!" And then they heard the feeble voice of Wren, pleading for water and demanding to be lifted to the light. The uproar of the final volley had roused him from an almost