In the very heart of the desert, far from food or water, these persecuted Indians finally found refuge. They learned that their enemies dared not brave the perils of the desert wastes, therefore, in times of peace, they carried deep into the desert supplies of food and water, the latter in the large earthen ollas, and cached them in the sands. Each warrior attended to the supply for himself and family. They did not store the supplies of the tribe together, but purposely scattered them. When an attack was made upon them, each man sought his own cache, and there he stayed till food and water were exhausted. By that time the zeal of the foe would have cooled off, no doubt, and they could return in safety to their homes. [Illustration: BLACK BUTTES--PHANTOM SHIP OF THE DESERT] The Indians thus persecuted have long since passed away, but the story of their tribulations is brought down to us in those ollas scattered over the burning plain. Before irrigation made habitable a portion of the Colorado Desert, persons who visited the dread region came back to civilization with strange tales of a phantom ship which was seen to sail upon a spectral sea. Sometimes this ship took the form of a full-rigged three-master; again it was a monster war-ship, with conning-towers and turrets, and great guns projecting fore and aft. The phantom vessel always appears in a certain portion of the desert and, instead of sailing slowly into sight and passing steadily on out of range of vision, as a well-regulated ship should do, it has the remarkable faculty of rising suddenly from the mystic sea and as suddenly sinking out of sight again. When the Imperial settlements were established in the land of mirages the mystery of the phantom ship was solved. About thirty miles south of the international line, in the republic of Mexico, rising out of a level plain, is a triple-peaked mountain known as the Black Buttes. When the atmospheric conditions are favorable, which is frequent, the Buttes, which from the Imperial settlements are below the horizon, are lifted by refraction into view, and under the transforming power of the mirage they appear like a great ship sailing upon a vast sea. Sometimes the three peaks are elongated and appear to be masts, while the solid granite bulk of the pile takes on the form of sails, seemingly set to catch the winds of the specter sea. Again the peaks are less elongated, and they appear like the heavier masts of a war-ship, and the sails are transformed into turrets and towers. The mirage eats into the sides of the mountains, leaving exposed several projecting points, which look like the heavy guns of a battle-ship. Then, perhaps, while the watcher strains his eye to catch the strange vision, it suddenly disappears from sight.