Our trail was taking us west of north, and we expected to reach the Saline about dusk and there encamp. The same strange evenness of country surrounded us. Over its surface, smooth and firm as a race track, we could drive a wagon or gallop a horse in any direction. Even the Bedouin has no such field for cavalry practice--his footing being shifting sand, while ours was the compact buffalo grass, so short that its existence at all could scarcely have been detected a few yards away. Sachem said he could think of no such cavalry field except that of his boyhood, when he slipped into the parlor and pranced his rocking-horse over the soft carpet; with which memory, he added, was coupled another, to the effect that while thus skirmishing on dangerous ground, his cavalry was attacked from the rear by heavy infantry and badly cut up. Numerous buffalo trails crossed our path, running invariably north and south. This is caused by the animals feeding from one stream to another, the water courses following the dip of the country's surface from west to east. Wallows were also very numerous, and we noticed as a peculiarity of these, as well as the paths, that the grass killed by treading and rolling does not renew itself when the spots are abandoned. More than once on the Grand Prairie of Illinois I have seen these wallows, made before the knowledge of the white man, still remaining destitute of grass. An old bull who has been rolling when the wallow is muddy, is an interesting object. The clay plastered over and tangled in his shaggy coat bakes in the sun very nearly white; and this it was, probably, that gave rise to the early traditions of white buffalo. Wherever on our route the rock cropped out along creeks or in ravines, it was the white magnesia limestone, and so soft as to be easily cut. Further west alternate pink and white veins occur, giving the stone a very beautiful appearance. We frequently found on the rocks and in the ravines deposits of very perfect shells, apparently those of oysters. Sachem suggested that they marked the location of pre-historic restaurants--the Delmonicos of the olden time, say fifty thousand years before the Pharaohs were born. He thought it possible that some future quarry-man might blast out an oyster-knife and money pot of quaint coins. Muggs thought this patch of our continent resembled Australia--"Not that it is as rich, you know, but there's so much of it." He even became enthusiastic enough to affirm that the land might be made profitable, "if some Hinglish sheep and 'eifers were put on it, you see." The Professor assured us that the country around was equal to the plains of Lombardy in point of fertility, and as the soil was of great depth, and rich in the proper mineral properties, it would undoubtedly become before 1890 the great wheat-producing region of the world.