When, then, we reflect, that of all those plains which spread out themselves upon our globe, the North American prairie possesses characteristics peculiar to itself, and to be met with nowhere beside; when we consider the demonstrations of a soil of origin incontestably diluvial; when we wander over the heaving, billowy surface, and behold it strewed with the rocky offspring of another region, and, at intervals, encased in the saline crust of the ocean-sediment; when we dive into its fathomless bosom, and bring forth the crumbling relics of man and animal from sepulchres into which, for untold cycles, they have been entombed; and when we linger along those rolling streams by which they {98} are intersected, and behold upon their banks the mighty indications of whirling, subsiding floods, and behold buried in the heart of the everlasting rock productions only of the sea, the conviction is forced upon us, almost resistlessly, that here the broad ocean once heaved and roared. To what circumstance, indeed, but a revolution of nature like this, are we to refer that uniform deposition of earthy strata upon the alluvial bottom-land of every stream? to what those deep-cut race-paths which the great streams have, in the lapse of centuries, worn for themselves through the everlasting rock, hundreds of feet? to what those vast salt-plains of Arkansas? those rocky heaps of the same mineral on the Missouri, or those huge isolated masses of limestone, rearing themselves amid the lonely grandeur, a wonder to the savage? Or to what else shall we refer those collections of enormous seashells, heaped upon the soil, or thrown up to its surface from a depth of fifty feet? Many phenomena in the Valley of the Mississippi concur to confirm the idea that its vast delta-plains, when first forsaken by the waters of the ocean, were possessed by extensive canebrakes, covering, indeed, its entire surface. If, then, we suppose the Indians, who passed from Asia to America in the early centuries of the Christian era, to have commenced the fires in autumn when the reed was like tinder, and the conflagration would sweep over boundless regions, we at once have an hypothesis which accounts for the origin of the prairies. It is at least as plausible as some others. The occasions of the autumnal fires may have been {99} various. The cane-forests must have presented an insurmountable obstacle in travelling, hunting, agriculture, or even residence; while the friction caused by the tempestuous winds of autumn may have kindled numerous fires among the dry reeds.