The present encampment offered no exception to the general rule. Abdur Kad'r, it is true, may have raged a little more extensively than usual when it was discovered that the well had caved in from sheer disuse, and several hours' labor would be necessary before some brackish water could be obtained. He did not trouble the Effendi with this detail, however. There was another more pressing matter to be dealt with, but, Allah be praised, that might wait till a less occupied hour, for the Frank was in no hurry, and he paid like a Kaliph. About four o'clock Irene was sitting in her tent making some belated jottings in a diary. Being thirsty, she called a servant, and told him to bring a bottle of soda-water. A few minutes later she heard a stumble, a crash, and a loud exclamation in Arabic. The man had fallen over one of the heavy stones to which the guy-ropes were fastened. She looked up smilingly, and wondered whether he would understand her if she said in French that she hoped he had not injured himself. The glass was broken, but the bottle was intact, for the native had caught it as he fell. "Ça ne fait rien," she cried encouragingly. Then she found that the Somali had risen to his knees, and was gazing skyward with every token of abject terror. At the same instant a strange commotion broke out in the camp. Through the open side of the tent she saw Europeans and natives all looking in the one direction--northwards. The Britons and Arabs had an air of profound astonishment. They pointed and gesticulated, but otherwise showed self-control. But the negroes were in a panic. For the most part they were kneeling. A few prostrated themselves at full length, and howled dolorously. The girl was alone, and she naturally felt alarmed. Royson was not far away, and he, like the rest, was held spellbound by some spectacle the nature of which she could not guess. Perhaps his thoughts were not far removed from Irene, because he turned and looked at her. "Come quickly, Miss Fenshawe," he shouted. "Here is the most wonderful mirage!" Was that it--a mirage? Why, then, this hubbub? She had grown so accustomed to the grim humor of the desert in depicting clear streams of running water, smooth, tree-bordered lakes, and other delightful objects of which the arid land dreamed in its sleep of death, that the excitement caused in the camp was wholly inexplicable. "What are you doing there?" she cried sharply to the frightened servant. "Go and get another glass, and take care you do not fall next time." If he heard he paid no heed. He continued to stare at the sky with wide-open eyes. Conscious of a fresh thrill of fear, she ran towards Royson. "What in the world--"