. INDUSTRIAL RESOURCES, ETC.,

OF THE

SOUTHERN AND WESTERN STATES.

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AMERICA.-INTERIOR VALLEY OF NORTH | 8,000,000 of square miles to be the area AMERICA-BOUNDARIES AND APPEARANCE- of North America, the valley contains CLIMATE, NATURAL HISTORY, POPULATION, 6,000,000. The northern half is almost uninETC. One of the most useful books, recently habitable; and of the remaining 3,000,000 published in this country, is the work of Dr. square miles, only one-third is as yet Drake, on the Principal Diseases of our inhabited, and that but sparsely, by a civilInterior Valley. Its prime object is to ized population. The western boundary of detail the aetiology, pathology, and treat- the valley is the Rocky Mountains, which ment of the diseases prevalent in that val- are composed of many chains united by ley. Preliminary to the direct considera- offsets, and run northwest to the Polar Sea. tion of the subject-matter, the author gives The range varies in height from 10,000 to a careful and lengthy sketch, geological, 14,000 feet above the level of the ocean; hydrographical, climatic, physiological, and and is distant, on an average, about 10° of social, of the Interior Valley; which, apart longitude from the Pacific. The vast infrom its usefulness to the practical physician clined plane on the east of the range is and medical student, is rich with matter 5,000 or 6,000 feet lower than the mountain highly interesting to the historian, geolo- at the point of recession from the range. gist, meteorologist, and all who delight in Upon this plain are found several tracts of the discoveries of science. Unlike most high table land, either projecting from the books, this has a permanent and increasing mountains, or insulated; of which the value. Its true worth will only be known principal are the Sweetwater Mountains and hereafter. It is, in short, a "Kñμa eis deí." Black Hills, the Llano Estacado, the Ozark The present article is intended as a review, Mountains, and the Coteau des Prairies. or rather brief condensation of the prelimi- The Apalachian Mountains form the nary sketch, which occupies much the eastern boundary, which run northeasterly, larger part of the volume, being 701 pages at an average elevation about one-fourth of in length. The more strictly medical por- that reached by the chain on the western tion is not well fitted for treatment in the margin. The plain which inclines from the pages of this work; and it deserves, Apalachian Mountains to the trough of the too, and will no doubt abundantly receive, valley, is much narrower than that running the consideration of writers much better from the mountain range on the other side. acquainted than ourselves with the entire It does not, like it, present elevated ranges circle of diseases and their aetiology. In of table land, but it is in general more rugdescribing the Interior Valley we shall fol- ged. Nor does the Apalachian chain, like low substantially the order adopted by Dr. the Rocky Mountains, extend to the Polar Drake, as upon the whole the most natural Sea, but is interrupted by the lakes and the and convenient. In a treatise so brief, we River St. Lawrence, and finally disappears can have little more to do than condense the before it reaches the coast of Labrador. subject-matter of the leading topics which The northern part of the valley is an imhe discusses, referring but little, if in any mense flat, stretching across from the Rocky respect, to the observations of other writers, Mountains to the Labrador coast, deeply and indulging not at all in original specula- indented in many places by the Northern tions. In accordance with this plan, we Ocean. proceed to treat of the Boundaries and Physical Appearance of the Interior Valley.

This region extends on the north and south, from the tropic of Cancer (lat. 23° 28′ N.) to the north polar circle, the whole length of the north temperate zone; on the east and west, from the Apalachian to the Rocky Mountains, widening as one passes from south to north. Supposing

On the north side of the valley lies Hudson's Bay; on the south, the Gulf of Mexico ; both penetrating deeply into the land, and each a reservoir of many large rivers, which originate in the centre of this region. Lakes are seldom found in the southwestern part of the valley, but are numerous in the more northern portion. Deserving of particular notice is that remarkable chain

In the rear of these alluvial bottoms are found, along many rivers, higher deposits of transported materials of less extent than the bottom lands, but evidently made by rivers much deeper and broader than any now existing. Closely related to these formations are the deposits on the general surface of the country, which extend from the sea of the south to an elevation of 1,500 feet on the mountain slopes and higher parts of the valley plain. They vary in depth from a few feet to 100 or more, and are composed of water-worn materials undeniably brought down from the north. These deposits are known as diluvion, drift, or post-tertiary. Co-extensive with them are found immense bowlders of granite and other primitive rocks lying at great distances from their parent strata, which were most probably transported, at a remote period, from the north, while imbedded in blocks of floating ice.

over an equal area, is the geological structure so simple and uniform; in no other does it so decidedly constitute the whole into one natural region.

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It is an obvious truth, that these formations have undergone but few disruptions from any force acting beneath. The Ozark Hills, of primitive rock, in Arkansas and Missouri, have, it is true, been pushed up through the secondary; and, in the former state, there are some volcanic appearances, in the midst of which we find the hot springs of Washita; still further, the great earthquakes of 1811 had their focus in the same quarter. But the whole region is of insignificant extent compared with the entire valley, which elsewhere shows scarcely a vestige of volcanic action. If, however, the rock formations of the interior of the continent still lie in their original position, all that were deposited are not here now. best geologists have come to the conclusion that much has been washed away; that vast submarine currents have swept the continent from north to south; scooped out or steepened the valley by cutting down its strata ; produced the general levelness of its surface, and finally left upon it the primitive bowlders and other drift or post-tertiary deposits which have been described."

Our

A farther description of the geological character of the valley can best be given in the words of Dr. Drake himself: "We must now penetrate the loose, upper coverings, and briefly indicate the nature of the strata below. In doing this, if we begin, as in the study of our physical geography, at the Gulf of Mexico, and proceed up the valley, along its synclinal axis, we shall find that The Southern Hydrographical Basin.—Our different rocks successively crop out, each limits preclude us giving more than a very to constitute the surface for a certain space, brief skeleton of this portion of Dr. Drake's and then to be succeeded by a deeper, which book. The amount of information on the has emerged from beneath it. We shall also various topics discussed, which he has acfind that we pass progressively from the cumulated from numerous sources as well as very newest to the oldest; though all the personal observation, and his generally logiformations which lie between those ex- cal deductions from a generalization of the tremes, in all countries, may not be met same, impart to this division of his work a with. Thus, around the Gulf of Mexico, we peculiar value. The nature of the subject begin on broad and deep alluvial deposits; first leads to the consideration of the Gulf then rise on diluvial or post-tertiary, and of Mexico, the position of which, its depth then on tertiary. To these, in Southern currents, temperature, tides, inundations Alabama and Mississippi, succeeds a creta- and coasts, are successively treated. Next ceous deposit, extending into west Tennes- comes the special topography of the Mexisee, followed by the coal formations of can coasts, of which we should like, had we Illinois and Missouri: then, advancing, we room, to present a short sketch, especially arrive in northern Illinois and Wisconsin, of that elaborate part relating to the delta of upon the Devonian shales and sandstones the Mississippi and its neighboring localiwhich underlie the coal basin; then, upon ties. Above its delta, as high up as the the silurian or transition limestones, sand-mouth of the Missouri, there lies on each stones and slates; and lastly, upon granite side of the Mississippi a series of low alluand other primitive rocks, which stretch northerly from Lake Superior to the Polar Sea. To the east and west of the line supposed to be traveled over, most of these formations spread out with great regularity and amplitude. Thus, there is a geological, not less than a geographical, unity in the Interior Valley. Not the unity of a single formation, existing everywhere, but the unity of one system of formations, deposited on a scale of vast extent, and subsequently subjected to the same influences, whether conservative or destructive. In no other country,

vial lands, which are divided into four distinct bottoms; the Tensas, the Yazoo, the St. Francis, and the American. Above the last commences the region described as the Upper Mississippi. The St. Francis bottom is terminated about thirty miles above Cairo by approaching rocky highlands. The alluvial region below is the most extensive of the kind in America, having an area of about 20,000 square miles. It extends from north to south, in a straight line, a distance of 400 miles, but more than 900, reckoning by the course of the river. The

Of the country lying between the Mississippi and the Rocky Mountains, not much, comparatively, is known, and the larger part of it is still a wilderness. It possesses, however, not a few claims to the attention of the naturalist, and is destined, in the course of time, to exercise a weighty influence upon the affairs of this republic.

major part of these bottom lands are subject | In the west, south, and east of the region, to annual overflows, from which, however. are extensive coal deposits, and their accomthey may be, and at some future time will panying sandstones, shales and limestone. be, reclaimed, by the intelligent application Devonian sandstones and shales, of an older of scientific principles. date, and also silurian limestone, still older, exhibit themselves in the central part. These rocks are hardened, and the streams cutting through them flow in narrow ravines, except among the deep and extensive diluvial deposits of Ohio, Indiana and Illinois. The waters of this are conveyed to the Mississippi by the Ohio. This latter river runs sluggishly, and in a wide channel, from the mouth of the Tennessee to its own. Above the Tennessee, as far up as the mountains, its banks are more elevated, two terraces of earth being frequently seen, and sometimes three. The lowest bottoms are argillaceous, with a deep soil. The second and third terraces consist of bowlders, pebbles, gravel and sand, over which is a stratum of loam, above which again is spread a thin layer of soil. The bowlders are composed of fragments of every kind of rock yet discovered east, northeast, and north of the Ohio; and they grow larger as one ascends northward. Organic remains are found in all three terraces, imbedded in a tenacious blue clay. Back of the terraces, at an average distance of one mile from the river, a line of hills, about 400 feet high, runs parallel with the stream for 600 miles, where they join the out-crops of the Apalachian coal formation.

A portion of East Louisiana, all Mississippi, nearly the whole of Alabama and West Florida, and West Georgia, lying east of the Mississippi and south of the Ohio basin, constitute another region of peculiar geological and hydrographical character. Its northeast portion, containing the extreme outlines of the Apalachian mountain range, is mountainous or hilly. The mountains in Georgia and East Alabama are composed of primitive rocks; those further west, of the older secondary limestones, and of sandstones and shales belonging to the coal formations. Coal appears on the surface at certain points of the Black Warrior and the Catawba. South and west of these occurs the most extensive cretaceous formation yet discovered in North America. In the north this formation is hilly; to the south appear frequent and extensive plains. The rivers of this part of the region are subject to inundation. South of the cretaceous formations are tertiary, post-tertiary, diluvial and alluvial deposits, which reach to the Gulf of Mexico. These deposits are even less consolidated than the cretaceous, which latter are friable in texture, of miscellaneous composition, and contain organic remains.

Another, and, in many respects, the most important hydrographical region of the southern third of the valley, is what is felicitously called the Ohio Basin. The central states of this basin are Kentucky and Ohio, which, however, do not lie wholly within it. It includes, also, the most of Tennessee, the north end of Alabama, the N. W. corner of Alabama, the west of North Carolina, western Virginia, the west of Pennsylvania, part of the S. W. corner of New-York, Indiana, and half of Illinois. Its elevation, not reckoning mountains, is more than double (700 to 1,000 feet) that of the regions already described. Some of its mountains rise from 2,500 to 5,000 feet. South of the Ohio the surface is ridgy, and to the east mountainous. In the northwest are tracts of level land resembling, in some respects, the plains of Alabama. Near the mouths of the Ohio and Tennessee are found cretaceous deposits, similar to those of the last described region. Everywhere else, at the surface, the geological formations are older.

The remainder of the Southern Basin is a narrow belt of land, extending 10° of latitude along the east bank of the Mississippi from the mouth of the Ohio. Its southern half lies in Illinois; its northern, in Wisconsin. The general aspect of the region is rolling, but prairies abound in all parts. The southern portion has an elevation of about 800 feet; the northern reaches a height of from 1,500 to 1,800 feet. In the south is the Illinois coal formation; towards the north the older rocks appear, and finally the primitive strata near the sources of the Mississippi.

The remaining three great hydrographical basins of the Interior Valley are quite different in their configuration and general character from that of which we have just given an imperfect, yet, as far as it goes, a correct outline. These three, want of space compels us to pass in silence.

Climate of the Valley.-The axis of the valley runs nearly in the same meridian from the torrid to the frigid zone; and. therefore, it presents every modification which is the effect of the sun's rays in various latitudes. But, though that luminary is the prime cause of all climatic phenomena, its influence is not always immediately asserted. Acting on continents and seas, it imparts heat to the atmosphere in very unequal degrees,