Even the last vestige of rock had now vanished, and we were speeding over a plain of red sand, above which the heat-laden air quivered. The temperature was steadily rising, and our Fahrenheit thermometer recorded eighty-six degrees. Torrence and I took off our coats, and renewed our search of the horizon in the hope of discovering hills, or any indication that we were approaching the end of the desert, but there was nothing but the red sand as far as the eye could reach with the aid of our strongest glasses. We were moving at a high rate of speed, and felt sure that a few hours would bring a change, but in this we were disappointed. We had penetrated more than a hundred miles into the solitudes of this desert when an extraordinary sight presented itself. A bird of such magnitude and terrible aspect swept across the sky that Torrence and I trembled with horror. There is nothing in size that I can compare it with, save the roc of the "Arabian Nights," and even that mythical bird, although possibly larger, had neither the plumage nor frightful countenance of this. The bird was flying diagonally across our path, although much above it, and to the best of my belief must have measured fifty feet from tip to tip of wing. Its feathers were of a dirty red, and its beak was hooked and powerful. Its eyes were fiery red, set in a circle of white, and as it looked down upon us there was a sinister expression, almost human in its intelligence. It was flying at terrific speed, and apparently without effort, and as it passed away we observed an unpleasant odor, which hung upon the air for some minutes after. It uttered no cry, but had evidently seen us, and left an impression bordering upon the supernatural, which was not easily effaced. It was the only living thing we had seen since entering the desert. The bird seemed to spring into the air from nowhere, and crossed our bow with such velocity—at an altitude of probably a couple of hundred feet—and vanished with such marvelous speed into the distance that had we not both seen it, I should have been inclined to ascribe it to some optical illusion. But there was no doubt that here was a creature unknown, or undreamed of in our own world. Could it be possible that the stories of the roc were founded upon any obscure tradition of this strange animal? Torrence believed that it was. He declared, moreover, that not a fairy tale existed but was built upon the conscious, or unconscious, knowledge of some past existing fact.