A Book of the United States. Various
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of lime, disposed in the most regular lamina, masses of limestone, in which seashells or organic remains are imbedded, retaining their distinct and original form. At every step, is presented the aspect of a country once covered by lakes or seas. The soil, stones, and exuviæ of lake or river formation, are, to all appearance, of comparatively recent origin. In the alluvial soils, to the depth of from twenty to an hundred feet, are found pebbles, smoothed by the evident attrition of waters, having the appearances of those masses of smoothed pebbles that are thrown on the seashore by the dashing of the surge. Leaves, branches, and logs are also found at great distances from the points where wood is seen at present, and at great depths below the surface. In the most solid blocks of limestone, split for building, deers’ horns and other animal exuviæ are found incorporated in the solid stone.
‘From its character of recent formation,’ says Mr. Flint, ‘from the prevalence of limestone every where, from the decomposition which it has undergone, and is constantly undergoing, from the prevalence of decomposed limestone in the soil, probably, results another general attribute of this valley—its character generally for uncommon fertility. We would not be understood to assert, that the country is every where alike fertile. It has its sterile sections. There are here, as elsewhere, infinite diversities of soil, from the richest alluvions, to the most miserable flint knobs; from the tangled cane brakes, to the poorest pine hills. There are, too, it is well known, towards the Rocky Mountains, wide belts that have a surface of sterile sands, or only covered with a sparse vegetation of weeds and coarse grass. But of the country in general, the most cursory observer must have remarked, that, compared with lands, apparently of the same character in other regions, the lands here obviously show marks of singular fertility. The most ordinary, third rate, oak lands, will bring successive crops of wheat and maize, without any manuring, and with but little care of cultivation. The pine lands of the southern regions are in many places cultivated for years, without any attempts at manuring them. The same fact is visible in the manner in which vegetation in this country resists drought. It is a proverb on the good lands, that if there be moisture enough to bring the corn to germinate, and come up, they will have a crop, if no more rain falls until the harvest. We have a thousand times observed this crop continuing to advance towards a fresh and vigorous maturity, under a pressure of drought, and a continuance of cloudless ardor of sun, that would have burned up and destroyed vegetation in the Atlantic country.
‘We have supposed this fertility to arise, either from an uncommon proportion of vegetable matter in the soil; from the saline impregnations mixed with the earth, as evidenced in the numberless licks, and springs of salt water, and the nitrous character of the soil, wherever, as in caves, or under buildings, it is sheltered from moisture; or, as we have remarked, from the general diffusion of dissolved limestone, and marly mixtures over the surface. In some way, spread by the waters, diffused through the soil, or the result of former decomposition, there is evidently much of the quickening and fertilizing power of lime mixed with the soil.’
The greatest length of the Valley of the Missouri is twelve hundred miles, its greatest breadth seven hundred. In the direction of the western rivers, the inclined plain of the Missouri extends eight hundred miles from the Chippewayan Mountains, and rather more than that distance from south to north, from the southern branches of the Kansas, to the extreme heads of the northern confluents of the valley. Ascending from the lower verge of this widely extended plain, wood becomes more and more scarce, until one naked surface spreads on all sides. Even the ridges and chains of mountains partake of these traits of desolation.
The celebrated valley called the American Bottom extends along the eastern bank of the Mississippi to the Piasa Hills, four miles above the mouth of the Missouri. It is several miles in width, and has a soil of astonishing fertility. It has all the disadvantages attending tracts of recent alluvion, the most valuable parts of it being liable to be swept away by the current of the Mississippi. ‘But the inexhaustible fertility of its soil,’ says Major Long, ‘makes amends for the insalubrity of the air, and the inconvenience of a flat and marshy situation, and this valley is undoubtedly destined to become one of the most populous parts of America. We were formerly shown here a field that had been cultivated, without manure, one hundred years in succession, and which when we saw it, (in August, 1816,) was covered with a very luxuriant growth of corn.’
The Ohio Valley is divided by the river into two unequal sections, leaving on the north-west side eighty thousand, and on the south-east one hundred and sixteen thousand square miles. The river flows in a deep ravine five hundred and forty-eight miles long in a straight line, and nine hundred and ninety-eight by the windings of the stream. In its natural state the Ohio valley, with the exception of the central plain, was covered with a dense forest. Open savannahs commence as far east as the sources of the Muskingum. Like the plain itself, those savannahs expand to the westward, and on the Illinois open into immense prairies. This valley may be regarded as a great plain inclining from the Apalachian system of the north-west, obliquely and deeply cut by the Ohio and its numerous confluents, into chasms from an elevation of four hundred feet to nearly the level of the streams. On the higher parts of the valley, the banks of the river rise by bold acclivities which wear almost a mountainous aspect. This boldness of outline imperceptibly softens in descending the Ohio, and on approaching the Mississippi, an extent of level woodland bounds the horizon. Ascending the rivers of the south-east slope, the scenery becomes more and more rugged, until it terminates in the ridges of the Apalachian chains: if the rivers of the north-west slope are followed, on the contrary, we find the landscape broken and varied near the Ohio, but around their sources flat and monotonous.
The Valley of the Hudson varies extremely in its width, being in some places contracted to the immediate neighborhood of the stream; in others extending forty miles. On the borders of the river the land is generally elevated. The Mohawk is bordered by two long ranges of hills presenting little variety of aspect. In the early part of its course it flows through extensive flats. The valleys of the Susquehanna and its branches are remarkably irregular. These streams traverse the whole width of the Apalachian chain of mountains, sometimes flowing in wide valleys between parallel ranges for fifty or sixty miles in a direct course, and at other times breaking through the mountain ridges. The valleys between the different ranges of the great chain extending throughout Pennsylvania are often twenty or thirty miles in width with a hilly or broken surface.
Valley of the Mohawk.
The only large valley in North Carolina lies between the Blue Ridge, and a parallel range called the Iron, Bald, and Smoky Mountains. It runs north-east and south-west, is one hundred and eighty miles in length, and from ten to forty in width.
The valleys of the small rivers of Tennessee are singularly beautiful and fertile, surpassing all others of the same description in the Western States. The valleys of the Cumberland and Tennessee differ little from the alluvions of the other great rivers of the west.
The Valley of the Connecticut is one of the most celebrated valleys of the United States for its fertility and beauty. It is a large tract of land extending from Long Island sound to Hereford Mountains in Canada, five miles beyond the forty-fifth degree of latitude. In the largest sense, it is from five to forty-five miles in width, and its surface is composed of a succession of hills, valleys and plains. The interval lands begin about twelve or fourteen miles from the mouth of the river. These are formed by a long and continued alluvion. The tributary streams of the Connecticut run every where through a soft and rich soil, considerable quantities of which, particularly the lighter and finer particles, are from time to time washed into their channels, by occasional currents springing from rains and melted snows. Wherever the stream moves with an uniform current these particles are carried along with it; but where the current is materially checked, they are in greater or less quantities deposited. In this manner a shoal is formed at first, which afterwards rises into dry land; this is almost invariably of good quality, but those parts which are lowest are commonly the best, as being the most frequently overflowed, and therefore most enriched by successive deposits of slime. Of these parts, that division which is farthest down the river is the most productive, consisting of finer particles, and being more plentifully covered with this manure. In the spring these grounds are almost annually overflowed. In the months of March and April,