Flagg's The Far West, 1836-1837, part 2; and De Smet's Letters and Sketches, 1841-1842. Flagg Edmund

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a word that must be, and hath been;

      A sound which makes us linger – yet – farewell!"

Childe Harold's Pilgrimage.

      Of the alluvial character of the celebrated American Bottom there can exist no doubt. Logs, shells, fragments of coal, and pebbles, which have been subjected to the abrasion of moving water, are found at a depth of thirty feet from the surface; and the soil throughout seems of unvarying fecundity. Whether this alluvial deposition is to be considered the result of annual floods of the river for ages, or whether the entire bottom once formed the bed of a vast lake, in which the waters of the Mississippi and Missouri mingled on their passage to the Gulf, is a question of some considerable interest. The latter seems the more plausible theory. Indeed, the ancient existence of an immense lake, where now lies the American Bottom, upon the east side of the Mississippi, and the Mamelle Prairie upon the west side, extending seventy miles northwardly from the mouth of the Missouri where the Bottom ends, appears geologically demonstrable. The southern limit of this vast body of water seems to have been at that remarkable cliff, rising from the bed of the Mississippi about twenty miles below the outlet of the Kaskaskia, and known as the "Grand Tower." There is every indication from the torn and shattered aspect of the cliffs upon either side, and the accumulation of debris, that a grand parapet of limestone at this point once presented a barrier to the heaped-up waters, and formed a cataract scarcely less formidable than that of Niagara. The elevation of the river by this obstacle is estimated at one hundred and thirty feet above the present ordinary water-mark. For more than an hundred miles before reaching this point, the Mississippi now rolls through a broad, deep valley, bounded by an escarpment of cliffs upon either side; and, wherever these present a bold façade to the stream, they are grooved, as at the cornice-rocks, by a series of parallel lines, distinctly traced and strikingly uniform. As the river descends, these water-grooves gradually rise along the heights, until, at the Grand Tower, they attain an altitude of more than an hundred feet; below this point the phenomenon is not observed.71 This circumstance, and the disruption of the cliffs at the same elevation, clearly indicate the former surface of the lake. Organic remains, petrifactions of madrepores, corallines, concholites, and other fossil testacea, are found imbedded in a stratum nearly at the base. Similar phenomena of the water-lines exist upon the cliffs of the Ohio, and a barrier is thought once to have obstructed the stream at a point called the Narrows, sixty miles below Louisville, with the same result as upon the Mississippi. The eastern boundary of the expansion of the latter stream must have been the chain of bluffs now confining the American Bottom in that direction, and considered a spur of the Ozark Mountains. This extends northeasterly to the "confluence;" thence, bending away to the northwest, it reaches the Illinois, and forms the eastern bank of that river. Upon the western side, the hills along the Missouri are sufficiently elevated to present a barrier to the lake until they reach the confluence of the rivers. At this point spreads out the Mamelle Prairie, sixty or seventy miles in length, and, upon an average, five or six in breadth. West of this plain, the lake was bounded by the range of bluffs commencing with the celebrated "Mamelles," and stretching north until they strike the river; while the gradual elevation of the country, ascending the Upper Mississippi, presented a limit in that direction.

      The event by which this great lake was drained appears to have been of a character either convulsive or volcanic, or to have been the result of the long-continued abrasion of the waters, as at Niagara. The rocks at the Grand Tower are limestone of secondary formation – the stratum being several hundred feet in depth, and imbedding hornstone and marine petrifactions throughout. They everywhere exhibit indications of having once been subjected to the attrition of rushing water, as do the cliffs bounding the Northern lakes, which have long been chafed by the waves. The evidence of volcanic action, or violent subterranean convulsion of some kind, caused by heat, seems hardly less evident. The former workings of a divulsive power of terrific energy is betrayed, indeed, all over this region. In the immediate vicinity of the Grand Tower, which may be considered the scene of its most fearful operations, huge masses of shattered rock, dipping in every direction, are scattered about; and the whole stratum for twenty miles around lies completely broken up. At the point in the range of bluffs where this confusion is observed to cease, the mural cliff rises abruptly to the altitude of several hundred feet, exhibiting along the façade of its summit deep water-lines and other evidence of having once constituted the boundary of a lake. At the base issues a large spring of fresh water, remarkable for a regular ebb and flow, like the tides of the ocean, once in twenty-four hours.72 At this spot, also, situated in the southeastern extremity of St. Clair county, exists an old American settlement, commenced a century since, and called the "Block-house," from the circumstance of a stoccade fort for defence against the Indians.73 By a late geological reconnoissance, we learn that, from this remarkable tide-spring until we reach the Grand Tower, the face of the country has a depressed and sunken aspect, as if once the bed of standing water; and was evidently overlaid by an immense stratum of calcareous rock. A hundred square miles of this massive ledge have, by some tremendous convulsion of Nature, been thrown up and shattered in fragments. The confused accumulation of debris is now sunken and covered with repeated strata of alluvial deposite. Evidence of all this is adduced from the circumstance that huge blocks of limestone are yet frequently to be encountered in this region, some of them protruding twenty or thirty feet above the surface. As we approach the Grand Tower – that focus, around which the convulsed throes of Nature seem to have concentrated their tremendous energy – the number and the magnitude of these massive blocks constantly increase, until, at that point, we behold them piled up in mountain-masses as if by the hand of Omnipotent might. Upon all this vast Valley of the West the terrible impress of Almighty power seems planted in characters too deep to be swept away by the effacing finger of time. We trace them not more palpably in these fearful results of the convulsions of Nature, agonized by the tread of Deity, than in the eternal flow of those gigantic rivers which roll their floods over this wreck of elements, or in those ocean-plains which, upon either side, in billowy grandeur heave away, wave after wave, till lost in the magnificence of boundless extent. And is there nothing in those vast accumulations of organic fossils – spoils of the sea and the land – the collected wealth of the animal, vegetable, and mineral worlds, entombed in the heart of the everlasting hills – is there naught in all this to arouse within the reflecting mind a sentiment of wonder, and elicit an acknowledgment to the grandeur of Deity? Whence came these varied productions of the land and sea, so incongruous in character and so diverse in origin? By what fearful anarchy of elements were they imbedded in these massive cliffs? How many ages have rolled away since they were entombed in these adamantine sepulchres, from which Nature's convulsive throes in later times have caused the resurrection? To such inquiries we receive no answer. The secrecy of untold cycles veils the reply in mystery. The effect is before us, but the cause rests alone with Omniscience.

      How wonderful are the phenomena betrayed in the geological structure of our earth! And scarcely less so are the ignorance and the indifference respecting them manifested by most of our race. "It is marvellous," says the celebrated Buckland,74 "that mankind should have gone on for so many centuries in ignorance of the fact, which is now so fully demonstrated, that so small a part of the present surface of the earth is derived from the remains of animals that constituted the population of ancient seas. Many extensive plains and massive mountains form, as it were, the great charnel-houses of preceding generations, in which the petrified exuviæ of extinct races of animals and vegetables are piled into stupendous monuments of the operations of life and death during almost immeasurable periods of past time." "At the sight of a spectacle," says Cuvier,75 "so imposing, so terrible as that of the wreck of animal life, forming almost the entire soil on which we tread, it is difficult to restrain the imagination from hazarding some conjectures as to the cause by which such great effects have been produced." The deeper we descend into the strata of the earth, the higher do we ascend into the archæological history of past ages of creation. We find successive stages marked by varying forms of animal and vegetable life, and these generally differ more and more widely from existing species as we go farther downward into the receptacle of the wreck of more ancient creations.

      That

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