The trilling of his cabin phone startled him to attention. He entered, took the receiver and heard Leclair's voice from the pilot-house: "Clouds on the horizon, my Captain. And I think there is a mountain range coming in sight. Would you care to look?" The Master, very grim and silent, went into the pilot-house. He had decided to make no mention of what had happened. The suicide must pass as an accident. He himself must seem to have no knowledge of it. Morale forbade the admission either of treachery or self-destruction, for any member of the Legion. The sight of vague, pearl-gray clouds on the far south-east horizon, and of a dim, violet line of peaks notched across the heat-quivering sky in remotest distances, struck him like a blow in the face. Clouds must mean moisture; some inner, watered plain wholly foreign to the general character of the Arabian Peninsula. And the peaks must be the Iron Mountains that Rrisa had told him about. They seemed to rebuff him, to be pointing fingers of accusation at him. Had it not been for his insistence-- "But that is all nonsense!" he tried to assure himself, as he took his binoculars from the rack and sighted at the forbidding, mysterious range. "Am I responsible for a Moslem's superstitions, or his fanatic irrationality?" The Master's own narrow escape from death disturbed him not at all. He hardly even thought of it. All he strove for, now, was to exculpate himself for Rrisa's death. But this he could not do. A sense of blood-guiltiness clung about him like a garment--the first that he had felt on this expedition. His soul, unemotional, practical, hard, was at last touched and wounded by the realization that Rrisa, pushed beyond all limits of endurance, had chosen death rather than inflict it on his sheik. And the thought that the faithful orderly's body was now lying on the flaming sands, hundreds of miles away--that it was already a prey to jackals, kites, and buzzards--sickened his shuddering heart and filled him with remorse. "Allah send a storm of sand--_jinnee_ to bury the poor chap, that's all I can wish now!" he pondered, as he studied the strange yellowish and orange tints in utmost horizon distances. The air, over the shimmering peaks, seemed of a different quality from that elsewhere. To north, to west, the desert rim of the world veiled itself in magic blue, mysteriously dim. But there, it glowed in golden hues. What, thought the Master, might be the meaning of all this? The Master had no time for speculation. The urgent problem of locating the Bara Jannati Shahr, beyond that inhospitable sierra, banished thoughts of all else. He inspected his charts, together with the air-liner's record of course and position. He slightly corrected the direction of flight. "Captain Alden" was already in the pilot-house, with Leclair. The Master summoned Bohannan tersely, and briefly instructed him: