A hundred miles west from the shack, stretching away from it in an almost unbroken expanse, was a desert within the desert. _Amole_ and sagebrush and cactus vied with each other to relieve the dead, flat, monotonous brown. Without movement anywhere, save for the heat-waves ascending, this expanse presented an unutterably drear and lonesome aspect. It terminated, or partly terminated--swerving off into the south beyond--in a long sand-dune running northeast and southwest. This mighty roll lay brooding, as did the world-old expanse fringing it, in the silence of late morning. Overhead a turquoise sky, low, spotless, likewise brooding, dipped down gracefully to the horizon around--a horizon like an immense girdle, a girdle which, as one journeyed along, seemed to accompany him, rapidly if he moved rapidly, slowly if he moved slowly--an immense circle of which he was the center. The sun was glaring, and revealed here and there out of the drifts a bleached skeleton, mutely proclaiming the sun as overlord, while over all, around and about and within this throbbing furnace, there seemed to lurk a voice, a voice of but a softly lisped word--solitude. Suddenly, like a mere dot against the skyline, there appeared over the giant dune to the north a single horseman. A moment he seemed to pause on the crest, then began the long descent, slowly, with almost imperceptible movement. He was not more than under way when another dot appeared against the skyline, a second horseman, close behind the first, who, like the first, after seeming to pause a moment on the crest, dipped into the long slope with almost imperceptible movement. A third dot appeared, two dots close beside each other, and these, like the others, dipping into the descent with almost imperceptible movement, for all the world like flies reluctantly entering a giant saucer. And then appeared another, the fifth, and then no more. The last also seemed to pause a brief moment on the crest, and also dipped with almost imperceptible movement into the long descent.