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Underlying all this vast territory are valuable beds of bituminous coal, in veins of from six inches to three feet. These veins crop out at Bedford and above. The lower and more valuable veins are beneath a good roof of shale and slate. Vast ledges and cliffs of both lime and sandstone are found in almost every neighborhood, though not so widely disseminated as to make them conveniently accessible to every settler.

In this article we have not spoken particularly of the coal formations in Chariton County, because we reserve that subject for our article on that county alone, which will be found in its proper place in this volume.

Very few of those counties above enumerated, except Chariton and Carroll, have had a corporate existence longer than twenty years. Chariton, which was organized in 1831, just after Missouri entered the Union, extended from the Missouri River to the Iowa line; Carroll, which was organized a year or two later, had formerly been a part of Ray, which then comprised all the territory west of Chariton County to Platte, and from the Missouri River to Iowa. The aggregate taxable property now in the thirteen counties is not less than twenty-five millions. They contain about twenty thousand voters, and perhaps a population, slave and white, of over one hundred and fifty thousand souls. In area the Grand River country is about onefifth of the State of Missouri, and the entire valley in Iowa and Missouri is about one-hundredth part of the territory acquired from France.

The timber most abundant in this valley are the various kinds of oak, of which there are one or two varieties not known in most of the Southern States. Some four or five varieties of hickory, pecan, in the southern part of it; cottonwood, linn, in some locations; sugartree and maple, ash, honey locust, water birch, and walnut of great size, of which the lumber is principally made for building. The oak timber has proved of great value, as from it are now being built at the Brunswick ship-yards hulls for steamboats which have begun to acquire a high reputation. The forks and knots of the walnut have afforded for several years quite a trade for some enterprising men, who hew them in blocks of convenient size and ship them to Cincinnati; and some of them are returned, no doubt, to the country where they grew, in the shape of furniture. The Grand River country produces all the timber of the Southern States except pine, cedar, poplar, and larch. The poplar does not grow in such high latitudes, and the larch is not known west of Illinois.

GEOLOGY.

MINERAL AND AGRICULTURAL RESOURCES OF MISSOURI.

BY G. C. SWALLOW, STATE GEOLOGIST.

IN presenting a systematic view of the Mineral and Agricultural resources of our State, it will be necessary to give a brief exhibit of the Geology as developed by the researches of the Geological Survey.

STRATIFIED ROCKS.

So far as observed, the stratified rocks of Missouri belong to the following systems:

[blocks in formation]

Previous to the commencement of the Geological Survey of Missouri but little effort had been made to trace out and classify the various deposits of the Quaternary System. This fact and the vast importance of these formations, both in our scientific and in our economical geology, have led us to undertake a careful investigation of this system as developed in our State. The results of our early investigations were given in the Second Annual Report of the Missouri Survey in 1854. This paper will include the facts there recorded, and those observed in our subsequent examinations, that it may present a full view of the present state of our knowledge upon this subject.

When it is remembered that these formations contain the entire geological record of all the cycles from the end of the Tertiary period to the present time, and that their economical value is greater than that of all the other formations combined, I shall need no apology for entering somewhat into details in recording the phenomena they pre

sent.

The Quaternary System comprises the drift and all the deposits above it all the strata included in the alluvion and diluvion of former authors. There are, within this period, four distinct and well

marked Formations in this State, which we have thus named in the order of their stratigraphical position.*

F. a.-Alluvium.

F. b.-Bottom Prairie.

F. c.-Bluff.

F. d.-Drift.

All of the latest deposits, all that have been formed since the present order of things commenced upon our Continent, are included in

F. a.-Alluvium.

All the deposits observed in the State, belonging to this formation,

are:

1st. Soils.

2d. Pebbles and Sand.

3d. Clays.

4th. Vegetable Mould or Humus.

5th. Bog Iron Ore.

6th. Calcareous Tufa.

7th. Stalactites and Stalagmites.

1st. Soils are a well-known mixture of various comminuted mineral substances, combined and mingled with decayed vegetable and animal remains, all comprising those ingredients peculiarly adapted to the nourishment of the vegetable kingdom. They are formed by the action of water, particularly in the form of rain and dews, cold, heat and other atmospheric influences, together with the co-operation of the vegetable and animal kingdoms.

The process by which soils are formed is one of the most beautiful and wonderful in nature. By a careful examination of what is transpiring in this great laboratory of nature, we may easily detect that process. If a rock, fresh from the quarry, be exposed, its surface will soon present a dull, earthy appearance, which is caused by a disintegration of its surface by atmospheric influences. Fine particles have been separated from the mass, and this meager coating of decomposing mineral matter will soon become the resting-place of numerous microscopic germs, which will be developed into a minute growth of lichens. These in turn will decay and add their remains to the pulverized particles, and prepare them to sustain a more vigorous growth of herbs, and to become the abode of the small insects and worms, which will burrow in their recesses, feed upon the increasing vegetation, and swell the mass both by their mechanical agency and by adding their exuvia to the accumulating soil. Larger plants and animals will accelerate the process by their more powerful agencies and by the greater amount contributed by their

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* See the general section of the rocks of Missouri in the Second Annual Report.

decaying remains.

Thus by almost imperceptible increments our

rich deep soils have been accumulated.

But the soils of Missouri are made up by the mingling of organic matter with the comminuted marls, clays, and sands of the quaternary deposits which cover all parts of the State, with a vast abundance of the very best materials for their rapid formation. Hence the soils of the State are very deep and wonderfully productive, save in those limited localities where the materials of the quaternary strata are unusually coarse or entirely wanting. But I shall speak more particularly of the soils, while treating of the rocks from which they were formed.

2d. Pebbles and Sand.-Many of our streams abound in waterworn pebbles, which constitute their beds, and form bars along their margins and across their channels. These pebbles were derived from the drift and the harder portions of the adjacent rocks. They vary in size according to the transporting power of the streams in which they are found.

The economical value of these pebbles for roads and streets, and the obstruction they often present to navigation, as in the Osage, give them unusual importance in our Geology. The Osage, Gasconade, Niangua, Marais des Cygnes, Sac and Spring Rivers of the South, and the Salt, South, North, Fabius, and Chariton of the North, all furnish good and abundant examples of these deposits, which have been formed by the action of those streams.

Sand is the most abundant material in the alluvial bottoms of the great rivers in the State. Vast quantities of it are constantly borne along by the irresistible current of the Missouri. Its whirling, rolling, turbulent waters form of it extensive bars in incredibly short periods, which they again wear away often still more rapidly than they were formed.

These sand-bars, so common in this stream, frequently extend along its bed several miles, with a breadth varying from one to five or six furlongs, and limited in thickness only by the depth of the water. A slight fall in the river leaves these vast sand-beds dry, when their surfaces are soon covered by a growth of weeds, interspersed with young willows and cottonwood.* The fickle stream, however, seldom leaves these sand-beds to a long repose, but returns to its old channel by a rapid removal of their loose materials.

*The sand of the Missouri, usually grayish brown and fine grained, contains a considerable quantity of lime and clay and vegetable matter, which render it very productive.

A disaster to the ill-fated steamer Timour, No. 2, presents a good illustration of the rapidity with which the Missouri forms and destroys these extensive deposits of sand. In the fall of 1853 this steamer ran upon a sand-bar, and was soon left high and dry some seventyfive or one hundred yards from the water, with a fair prospect of leaving her timbers to decay in the young forest of willows and cottonwood which would soon spring up around her. But the current changed and cut its way through the sandy stratum upon which the boat rested, and floated her away uninjured to the great City of the West. And all this transpired in a few weeks.

As these sand-bars are cut away, their perpendicular faces present beautiful illustrations of their stratification, which is usually very irregular and complicated, as might be expected from the changeable character of the current.

But water is not the only agent engaged in producing the irregular stratification of the sand-bars of the Missouri and Mississippi Rivers. When these sand-beds become dry by exposure, the winds easily transport and rearrange their light and fine materials. Such quantities are moved by high winds, that the entire channels of the rivers are obscured by the dense clouds of moving sand. The stratification of the sand-beds thus formed is very interesting and complicated, and aids us in explaining some examples of stratification observed in the older rocks.

At high stages of water, both the Missouri and Mississippi overflow their low bottoms, and leave deposits of a grayish-brown or a grayish-yellow sand similar to that in the sand-bars mentioned above. The thickness of these beds depends upon the height and continuance of the overflowing waters, varying from a mere perceptible stratum to several feet.

That from the flood of 1844 is very conspicuous throughout the length of the Missouri bottom. It is sometimes six or eight feet thick, particularly in low bottoms, so heavily timbered as to obstruct the current.

At the lower end of Waconda Prairie this deposit is very evenly distributed over its surface; but it increases in thickness as the prairie descends to the low timbered bottom, lower down the stream, where it is six or seven feet, and its surface becomes very irregular, like the surface of a lake when disturbed by a high wind or a chopped

sea.

The lower extremity of Waconda Prairie and the cottonwood bottom below finely illustrates these phenomena. The small timber is a young growth of cottonwood, which has sprung up since 1844,

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