In the south distance, before the dust had filled the air, there had been visible the jagged outline of the San Francisco Mountains. Now nothing was visible save the immediate wind-swept surface of the earth, the troubled dunes, and the higher desert ridges. Yuen Ming Chu had no intention of letting his despoilers beyond the range of his vision. And he was obliged to shorten the intervening distance; for the hot wind rose into a hurricane. [Illustration] He rapidly overtook the two wobbling, stumbling men. They were letting themselves be swept directly with the drift of the storm, hunched over, running, scurrying up the ridges, sliding down. They were not concerned with their pursuer's presence. They had shorn him of harm. He looked down at them, as they picked themselves up under the leeward of a sand drift. "You are drifting with the storm," shouted Ming Chu. "It is blowing a west angle to our course. You must walk so that it strikes first the point of the left shoulder." "You lead out," faintly responded the authoritative one of the pair. "Move on ahead, there. We'll follow. But no damned monkey business, Chink!" Prince Chu looked back at them as he brushed by with his burro, and he interrupted a significant exchange of glances between them. Steadily he bore ahead, and the very surface of the earth seemed to be lifting up to bear them all down into smothered oblivion. He was fully at the mercy of these plunderers who followed him six paces in the rear. He had read the meaning in the look which they had exchanged. They intended to coolly shoot him down when they had done with his guidance. The drifting sand would do the rest. "Such as it is to be, so it shall be," meditated this silver-haired son of the Great Ancients. They were not following him easily. The driven sand cut through their ragged clothing. Occasionally one of them fell headlong. Neither tried to assist the other. The shorter one seemed to be the sturdier of the two. The long-legged one stumbled more frequently. One or the other of them frequently called on him to wait for them. He perforce obeyed. When they were close behind him, Ming Chu could see contortions of fear at work in the pallid face of the gasping Shorty. Each time that his partner went down he registered a look of satisfaction. Prince Chu smiled inwardly. The prospect of violent death was fermenting in Shorty's brain. His features portrayed a fixed terror born of the alleged fate dependent on his losing possession of the marvelous opal. His mind was caught in the dread that the prophesy's fulfillment was bearing down upon him.