Suddenly a woman’s stifled scream tore the silence apart. It ceased abruptly, suggestive of the clapping of a hand over the mouth of the one who had screamed. The sound seemed to come from the recess at the far side of the garden. In a dozen lithe bounds Robert had rounded the wing of the palace, and was in sight of the far end of the garden. He fancied that he caught a fleeting glimpse of some light, loose garment in the dark shadows of the recess. A faint sound as of the stealthy turning of a lock followed and all was again quiet. A moment later Professor Palmer joined him. “What’s up?” he asked huskily, puffing from his exertion of attempting to keep pace with Robert. “Don’t know. Imagined I saw a woman’s garment fluttering a moment ago. Suppose we have a look over there in that black corner.” A solitary dark window looked out sinisterly from the recess. Robert had an uncomfortable feeling that they were being watched from it as they approached. As they drew close to the wall where it joined the building Robert caught sight of something they had failed to notice before in the darkness. This was a massive, closed door in the corner of the wall. “The door I heard locked a minute ago,” whispered Robert. He put his shoulder to it, but failed to move it. The night again was as silent as a grave. In vain they listened for some sound beyond the locked door till finally they gave it up and returned to the comfortable warmth of their suite. * * * * * That night Robert tossed about nervously until he despaired of sleeping. He envied the professor, whose measured breathing he could hear from the adjoining room. Later he dropped off into troubled slumber and dreamed once more of the maid of the desert. This time the scene was a different one, the palace garden the setting instead of the desert. Step by step the incident of that evening was enacted again with this difference: in some strange manner he could see all that occurred in a garden which was on the other side of the wall with the locked door. A maid--his maid--emerged from a door in the palace and hurried across the garden. Reaching the wall she fumbled among a mass of vines which clung to its side. She pulled something from behind them which he could not at first make out in the shadow. As she propped it against the wall he recognized it as a small ladder. This she mounted quickly, looking back several times as if fearing pursuit. Just as she reached the top of the wall a man ran out of the doorway from which she had first appeared, and looked around swiftly. He was immediately joined by another. Both caught sight of the girl as she paused to drop on the other side of the wall. Held by some invisible force Robert found it impossible to go to her assistance. He was obliged to remain merely a spectator.