I looked about me. Where was the air ship? The vessel was nowhere in sight, and I wondered if I had come farther than I thought. It was impossible that the distance between us had made it invisible. The machine had simply disappeared from the face of the earth, suddenly and inexplicably. In every direction the desert stretched, and above was the sky. It was impossible that Torrence could have repaired the damage without me, and sailed. I was bewildered, horrified. I felt that I was lost forever and irredeemably, for even my footsteps had been obliterated by the creeping of the sand, doubtless the effect of subterranean heat. I was crushed; and as I sat there, burning and aching in every inch of my body, and in mental agony as well, I cried. Then I remembered the undulations of the plain, and was convinced that the air ship was lying in one of the hollows between them, just out of sight. Although this thought was comforting in one sense, it was not so in another, inasmuch as it did not relieve the situation. The vessel was as hopelessly lost as if she had sailed away without me. At least so I felt about it. I shouted as loud as possible, but at best could not have been heard a hundred yards, for my throat was parched and painful, and its power gone. Death seemed close at hand, and closer, perhaps, from a certain apathy which was stealing over me. Stretching out at full length upon the sand, the cliffs beyond had an ominous look. There was no appearance of life, neither was there tree or bush to indicate the presence of water. Sheer cliffs, of unscalable form, towered above me. Like the ruin of some vast Titanic home the rocks were piled in huge masses, uncouth blocks and pinnacles, from the sandy depths beneath to the vapory heights above. The wind whispered through dark alleys and deserted passages, and at open casements; at least these sounds appeared to reach me in that awful solitude, and I was overpowered with the sense of a breathing, intelligent world around me. As I lay there staring stupidly up at the rugged forms of tower and pinnacle surmounting this strange wall, I was struck with the appearance of dark spots in the face of the cliff near the summit, which had a peculiar regularity, as if they might be windows, cut or blasted out by human hands. This interested and set me to examining the place more carefully, when I became astounded at what I could no longer doubt was an artificial design extending along the top of the precipice. Could it be possible that this great natural wall was crowned with a castellated structure built by men, and so closely resembling the cliff itself as to be indistinguishable from it?