Yar Ali squinted carefully down the blue barrel of his Lee-Enfield, called devoutly on Allah and sent a bullet through the brain of a flying rider."_Allaho akbar!_"The big Afghan shouted in glee, waving his weapon above his head, "God is great! By Allah, _sahib_, I have sent another one of the dogs to Hell!"His companion peered cautiously over the rim of the sand-pit they had scooped with their hands. He was a lean and wiry American, Steve Clarney by name."Good work, old horse," said this person. "Four left. Look--they're drawing off."The white-robed horsemen were indeed reining away, clustering together just out of accurate rifle-range, as if in council. There had been seven when they had first swooped down on the comrades, but the fire from the two rifles in the sand-pit had been deadly."Look, _sahib_--they abandon the fray!"Yar Ali stood up boldly and shouted taunts at the departing riders, one of whom whirled and sent a bullet that kicked up sand thirty feet in front of the pit."They shoot like the sons of dogs," said Yar Ali in complacent self-esteem. "By Allah, did you see that rogue plunge from his saddle as my lead went home? Up, _sahib_; let us run after them and cut them down!"Paying no attention to this outrageous proposal--for he knew it was but one of the gestures Afghan nature continually demands--Steve rose, dusted off his breeches and gazing after the riders, now white specks far out on the desert, said musingly: "Those fellows ride as if they had some set purpose in mind--not a bit like men running from a licking.""Aye," agreed Yar Ali promptly and seeing nothing inconsistent with his present attitude and recent bloodthirsty suggestion, "they ride after more of their kind--they are hawks who give up their prey not quickly. We had best move our position quickly, Steve _sahib_. They will come back--maybe in a few hours, maybe in a few days--it all depends on how far away lies the oasis of their tribe. But they will be back. We have guns and lives--they want both. And behold."The Afghan levered out the empty shell and slipped a single cartridge into the breech of his rifle."My last bullet, _sahib_."Steve nodded. "I've got three left."The raiders whom their bullets had knocked from the saddle had been looted by their own comrades. No use searching the bodies which lay in the sand for ammunition. Steve lifted his canteen and shook it. Not much water remained. He knew that Yar Ali had only a little more than he, though the big Afridi, bred in a barren land, had used and needed less water than did the American; although the latter, judged from a white man's standards, was hard and tough as a wolf. As Steve unscrewed the canteen cap and drank very sparingly, he mentally reviewed the chain of events that had led them to their present