The image produced by the reflected rays will appear inverted, and below the real object, just as an image reflected in the water appears when observed from a distance. The phenomena are frequently much more strange and complicated, the images being often much distorted and magnified, and in some instances occurring at a considerable distance from the object, as in case of a church seen over the sea or an inverted vessel sailing over the land. If the object is a cloud, or portion of sky, it will appear by the reflected rays as lying on the surface of the earth and bearing a strong resemblance to a sheet of water; also, as the reflecting surface is irregular, and constantly varies in position, owing to the constant communication of heat to the upper stratum, the reflected image will be constantly varying, and will present the appearance of a water surface ruffled by the wind. Thus in the deserts of lower Egypt, Persia, Turkestan, and on the great Western plains of the United States, whole caravans have been led from the trail by thirst toward an inviting lake which appears to be but a few miles away. If the ground is favorable the mirage may be dispelled as the observer advances, but in others it is like an ignis fatuus, hovering ever in sight, but always beyond reach, until the victim succumbs to thirst and his body is left a monument to his own misunderstanding of one of nature’s most fascinating jokes. Buffalo Bill came to the trapper’s side on the rim of the basin, where Nomad pointed to the southwest. The sky looked a lead-colored haze that held well down to the horizon, with a belt of clear blue underneath, but nearer, and seeming a few miles away, was a tracery in the heavens, apparently far below the clouds, of a vast map of the plain. The buttes, and ravines, and gashes, the buffalo wallows, skulls, and clusters of weeds, were laid out across the sky with a variation of distinctness and color. The distortions were surprising, the images coming suddenly nearer or fading away in the distance. A little brook suddenly grew to a great river and objects seemed to be moving on its surface. But more surprising than all the rest was the mirrored outline of a crack in the hard-baked surface of the plain. Reflected there in the peculiar morning sky, the crevice looked to be several feet wide and running for a long distance in a direction that allowed the smaller or farther end to fade out and disappear in the distance, while the nearer approached diagonally until it appeared scarcely half a mile away, ending in the side of a strangely marked butte. This latter, seen top down in the sky, appeared hollow, surrounded by a high, square-topped wall. And the centre of the hollow reflected green.