No. 71. Red valley soil from 13 miles south of Jacksonville, Calhoun county. red, Spanish, and post oaks, hickory, dogwood, and short-leaf pine; color, dark-red. a good proportion of the valley below Jacksonville and around Alexandria.

Depth, 12 inches; vegetation,
This kind of soil occurs over

No. 76. Red valley soil from near Mrs. Walker Reynolds' place, Talladega county. Depth, 12 inches; vegetation, red, Spanish, white, and post oaks, sweet and sour gums, and hickory; color, dark-red. This is a fair sample of the red soils which make the valley of Talladega one of the most beautiful parts of the state. The same soils are seen farther south, in Shelby and Bibb counties, those around Montevallo being of this nature.

No. 45. Red upland soil (dolomite) from near Pratt's ferry, Bibb county. Depth, 12 inches; vegetation, white, black, post, and other oaks, chestnut, hickory, walnut, mulberry, dogwood, with occasional black gum and cedar; color of soil, brown; of subsoil, reddish-brown.

No. 67. Little Cahaba valley soil (dolomite) from 6 miles southwest of Springville, Saint Clair county. Depth, 12 inches; vegetation, red, black, and Spanish oaks, hickory, chestnut, sweet gum, and persimmon; color, reddishbrown.

No. 69. Gray upland soil (dolomite), 1 mile north of Ashville, Saint Clair county. Depth, 10 inches; vegetation, red and Spanish oaks, poplar (Liriodendron), dogwood, and short-leaf pine, with some sweet gum and persimmon; color, brownish-gray. Both soil and subsoil are commonly filled with angular fragments of chert.

In comparing these soils with each other it is seen that they are all tolerably good soils, having an adequate supply of available potash (except in the case of No. 69), phosphoric acid, and also of lime and magnesia. In these respects the red soils, as a class, are superior, but the gray soil has on its side the advantage of being more easily tilled, as it is thrifty because of a large percentage of lime, and is generally considered a safer soil. No. 76 is rather deficient in lime, and also in available phosphoric acid. In retentiveness of moisture the upland soil (No. 45) is a little deficient, and in its composition also it approaches closely to the gray soil.

The soils which most resemble the above are those of the Tennessee valley, in which there are the two varieties of red and gray, bearing to each other about the same relations as are seen in the above analyses. The Tennessee valley soils are, if anything, slightly better than those of the region we are discussing.

In the county descriptions will be found fuller discussions of the qualities of these soil varieties from the farmers' standpoint.

Chazy and Trenton.-The lowermost of the Trenton rocks are impure argillaceous limestones and purer blue limestones, the upper calcareous shales. As a rule, the limestone predominates, and the prevailing soils are, therefore, good strong loams, somewhat calcareous and resembling the soils of the lower part of the dolomite, or those of the Saint Louis group of the sub-Carboniferous. The formation as a whole is valley-making, but the lower beds, which are often aluminous, frequently form low, rounded hills, along the sides of which the strata outcrop in long step-like ledges. In such cases they are usually covered with a growth of cedars.

In the subordinated valleys in the eastern part of the Coosa valley the Trenton rocks are usually associated with those of the dolomite, the latter commonly forming the northwestern and the former the southeastern side of the valley range; but the dolomite, as a rule, far exceeds the Trenton in superficial extent. In the anticlinal valleys the Trenton rocks are found as a narrow belt on each side of the central area of dolomite and shale. In many instances they may be found high along the sides of the ridges of the Clinton or Red Mountain group, even occurring nearly up to the summits of some of them. The outcropping ledges of limestone are then usually covered with a dense growth of cedars, and the name of Cedar mountains commonly given to them is not inappropriate. In the valleys also there are frequent patches of the rocks nearly bare of soil and forming cedar glades. The shaly upper division of this group is of secondary importance.

In Jones' and the other anticlinal valleys the purer limestones of this age are commonly seen outcropping here and there in the lower places in smooth, rounded masses of a bluish color, rising very slightly above the general surface. Very little of the original growth is now standing in those parts of the valleys which have usually been long under cultivation. The soils are brownish sandy loams with yellowish subsoils. The slightly elevated knolls that vary the uniformity in these valleys have sandy soils, and are usually covered with short-leaf pine thickets of secondary growth. There are also spots of low, wet, boggy soil, not at all, however, like the flatwoods before described. The following analysis will show the composition of some soils of this kind:

No. 123. Sandy brown-loam soil (Trenton) from 3 miles west of Birmingham, Jefferson county. Depth, 10 inches; vegetation, red and willow oaks, sassafras, and grape-vines-little of the original growth to be seen; color, brown at top, passing into yellow at 3 inches depth.

Sandy brown-loam soil (Trenton limestone), Jefferson county.

This is a soil of only average fertility, and probably of little durability, but thrifty and easily tilled. Clinton. The rocks of this formation, calcareous sandstones and shales, with beds of red iron ore, yield sandy soils of considerable fertility, but their location on the steep hillsides makes them of little importance in agriculture. The red-ore ridges are in reality made up of three formations: the Clinton, the black shale, and the siliceous division of the sub-Carboniferous. The usual position of these ridges is on each side of the anticlinal valleys of the state, skirting the escarpments, of Coal Measures, which form the borders of these valleys. In some places the ridges are duplicated on one side of the valley; but they are never wanting in the positions above indicated (except where ingulfed by a fault), though sometimes quite insignificant in height on one side.

In the western or anticlinal portion of the Coosa valley a red-ore ridge runs parallel with the eastern edge of Lookout mountain, and a similar ridge skirts the western edge of the Coosa coal-fields in the normal positions above mentioned; but in the eastern or faulted portion of the valley the red ridges are not associated with the Coal Measures, but form parts of synclinal basins holding the rocks of the sub-Carboniferous formation. The four localities thus far known of red ore ridges in the eastern part of the valley are in the Dirtseller and the Gaylor mountains, in Cherokee county, in the mountain near Columbiana, in Shelby, and in the vicinity of Pratt's ferry, in Bibb county. The mountain near Columbiana has along its base a conglomerate which probably underlies the Red Mountain rocks proper and belongs to the Medina group. Where the red ridges are not too steep for cultivation their soils are well adapted to most of the southern crops, especially grain. The analysis which follows shows the average red mountain soil.

No. 68. Red Mountain soil (Clinton) from 3 miles north of Springville, Saint Clair county. Depth, 10 inches; vegetation, large poplars, white oaks, and chestnuts, with hickory, black gum, and red oak; color, chocolate-brown when cultivated.

For the amount of insoluble matter this soil has a fair percentage of potash, a large percentage of phosphoric acid and lime, and is rather above the average in fertility, as might be inferred from the luxuriance of the forest growth which it supports. The Red Mountain soils are admirably suited to the production of small grain, but not for cotton, which is inclined to run to weed, at the expense of the fruit, unless restrained by superphosphates or other similar manures.

The above remarks apply to the red or brown soils only of these ridges, for it must be remembered that they have gray, flinty, gravelly soils usually on one side and the red soils on the other.

The black shale, which follows next after the Clinton, rarely, if ever, takes part in the formation of cultivated soils. It is, at best, only a few feet thick, and as it nearly always occurs in steep ridges it is of comparatively little importance agriculturally.

Sub-Carboniferous.-In the Coosa and outlying valleys of middle Alabama this formation, though occurring only in narrow belts, is of great importance, since it forms the basis of some of the most desirable farming lands in the region of its occurrence.

The surface distribution of the sub-Carboniferous strata is practically the same as that of the red-ore ridges, for, besides forming a part of the ridges themselves, they occupy the depressions between these ridges and the escarpment of the Coal Measures, and in the Coosa valley they form the surface in the four small synclinal basins mentioned in a preceding section. This formation, as a whole, has two well-marked divisions-the mountain limestone and the siliceous. The former, as its name implies, occurs along the sides of the mountains of the Coal Measures, and presents no tracts of arable land in this part of the state.

The lower group, which is generally known as the siliceous, is itself subdivided, and its two parts are very unequally concerned in the formation of tillable lands, for the lowermost or more siliceous division is, as we have seen, usually associated with the Clinton rocks in the formation of the red-ore ridges, which, because of their steep slopes, are not much in cultivation. The upper and more calcareous division of the siliceous group is the true soil-former of these belts. These soils are yellowish, reddish, and brown loams, similar to the soils of the red lands of northern Alabama, which are based upon the same rocks.

The principal discussion of this class of soils will be under the next division in northern Alabama, but the following analysis of a soil from Dry valley, in Cherokee county (basin of the Dirtseller), may serve to represent the composition of the soils of the narrow valleys of middle Alabama:

No. 111. Red lands soil (sub-Carboniferous), Dry valley, Cherokee county, 1 mile northeast of Gaylesville. Depth, 8 inches; vegetation, red, post, white, and Spanish oaks, hickory, persimmon, chestnut, black gum, sourwood, dogwood, and a second growth of short-leaf pine; color, reddish-brown.

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This soil is somewhat deficient in its retentiveness of moisture, as also in phosphoric acid; otherwise it is a very good soil. The high percentage of lime makes available its whole content of plant-food. The percentage of humus in this soil is also quite high, as well as the proportion of phosphoric acid immediately available.

A fuller exhibition of the characters and variations of these sub-Carboniferous brown loams will be seen under the heading of "The Tennessee Valley Region" (page 28), where they are widely distributed, and are of great importance agriculturally.

The Coosa and Cahaba coal-fields, although occurring in this division, are best described, together with the Coal Measures of the Warrior field, under the next division.

NORTHERN DIVISION.

This division, as already stated, adjoins the first or middle division on the northwest, and embraces most of the state lying north and west of a line drawn from Chattanooga, Tennessee, through Birmingham, nearly to Tuscaloosa. The area thus included is estimated at 9,700 square miles, and embraces the following counties and parts of counties: All of Lawrence, Winston, Walker, Cullman, Morgan, Limestone, and Madison, and parts of De Kalb, Cherokee, Etowah, Jackson, Marshall, Blount, Jefferson, Tuscaloosa, Fayette, Marion, Franklin, Colbert, and Lauderdale.

The two parts into which this division is, by its topographical and agricultural characters, naturally subdivided, are: 1. The continuation and terminus of the great Cumberland table-land, which in Alabama includes the Sand mountain and its outliers, Lookout and Blount mountains, on the south, and the detached spurs lying beyond the Tennessee on the north and the Warrior basin, into which the table-lands of Sand mountain gradually sink beyond the southwestern line of Blount county. 2. The great valley of the Tennessee.

The rock masses which in this division are concerned in the structure of the country and in the production of the soils are referred to two formations, the sub-Carboniferous and the Coal Measures. In some parts of this area the stratified drift overspreads the country rocks and forms the soils, but the drift belt, together with its outreaching marginal parts, which overlap other formations, will be treated as a whole under another head. The approximate horizontality of the strata, and the circumstance that the soils, almost without exception, have been derived from the immediately underlying rocks, have already been commented upon, and the close connection of the agricultural with the geological features has been pointed out. The two component parts of this division are most conveniently described separately.

COAL-MEASURES REGION.

COOSA AND CAHABA COAL-FIELDS.

The Coosa field embraces about 30 square miles in the northwestern part of Calhoun, about 150 square miles in Saint Clair, and about 235 square miles in Shelby county, making an aggregate of 415 square miles.

The Cahaba field includes about 50 square miles in Saint Clair, 100 in Jefferson, 160 in Shelby, and 125 in Bibb county, aggregating 435 square miles. Only 75 square miles in Bibb county are free from drift, so that the area depending upon the Coal Measures for its soil is reduced to 385 square miles.

In both these fields the strata, consisting of sandstones, conglomerates, shales, and coal beds, are tilted at considerable angles, and, possessing varying degrees of resistance of disintegration and erosion, have been very unequally degraded. The main ridges and valleys have the general direction of northeast and southwest, corresponding to the outcrops of the tilted strata; but this uniformity is often greatly obscured, and in places is obliterated by the irregularities produced by the streams which traverse the fields across the outcrops. In the presence of these inequalities, produced by the folding or the tilting of the strata, these fields differ from the great Warrior field, where the topographical features have no such direct connection with the geological structure. All the coal-fields have most of their characters in common; hence a further description of the topography, as well as of the agricultural features, can be well deferred till we come to speak of the Warrior field. It seems to be well established that the three coal-fields of Alabama were once continuous, and that they have been separated by folds (since denuded) and by faults.

THE WARRIOR FIELD.

That part of the Coal Measures of Alabama which is drained by both forks of the Warrior river and their tributaries has received the name of the Warrior coal-field. This field may be divided into two parts: the plateau or table-land, and the Warrior basin proper.

The table land.-It is characteristic of the table-lands or plateaus that the limestone beds, which underlie the capping of Coal Measures rocks, are above the general drainage level of the country. This arrangement of the two classes of strata determines in great measure the character of the scenery, for the removal by erosion of the more perishable limestones causes the undermining of the harder sandstones above, which from time to time break off with vertical faces, forming cliffs. In height the plateaus diminish continuously toward the southwest, passing gradually into the Warrior basin. In the state of Tennessee their elevation above the surrounding country varies from 850 to 1,000 feet. In Jackson and Madison counties some of the spurs attain an equal height, but further southwest, in Morgan and Marshall, the elevation will not average more than 550, and in Cullman and Blount counties not more than 360 feet, and near the Mississippi line they come down to the drainage level. The main body of the table-land is known as Sand mountain, lying between the Sequatchie fold, or Brown's and Tennessee valleys, on the northwest, and Wills' and Murphree's valleys on the southeast, and include parts of De Kalb, Jackson, Marshall, and Blount counties. The highest parts of this table-land are to be found along its edges overlooking the valleys above mentioned, and there is a general slope both ways toward the center of the plateau, which thus becomes a shallow, elevated trough.

Beyond Wills' valley is Lookout mountain, an outlier of Sand mountain, and beyond Murphree's valley (southeast) Blount mountain, a spur of the main table-land. All these parts have similar structure, and their elevated rims, adjoining the valleys, are usually only slightly indented by the water-courses, except where some large stream leaves the plateau, as in the cases of Little river, on Lookout, and Short creek, on Sand mountain. Northwest of the Tennessee river, however, the tributaries of that stream have cut the elevated lands belonging to this division into a number of more or less isolated peaks, some of which, especially in the northeastern part of the state, have still the capping of Coal Measures, which have been entirely removed from many of those lying farthest toward the west. Overlooking the Tennessee valley, in Lawrence and Franklin counties, the elevated rim, which is locally called Sand mountain, is the border of the Warrior basin, and will be considered along with it.

Approximately, the area of the elevated lands or plateaus as above limited would be about 1,690 square miles on Sand mountain and its spur in Jackson, De Kalb, Marshall, Etowah, Morgan, Saint Clair, and Blount counties, about 290 square miles on Lookout mountain, in De Kalb, Cherokee, and Etowah, about 580 square miles in the detached spurs of the Cumberland northwest of the Tennessee, in Jackson, Madison, and Marshall, and to these might be added about half the area of Cullman county, whose measures partake of the characters of both the table. lands and of the basin, about 295 square miles; aggregating, in all, 2,855 square miles. A not inconsiderable part of this area north of the Tennessee is mountain slope, and is not strictly table-land.

The Warrior basin.-This, like the table-land, is in general a trough, shallow and sloping from northeast to southwest, with slightly elevated rims next to the Tennessee valley on the north and Jones' valley on the south. As Brown's valley divides the plateau, so its continuation southwestward as a ridge divides the basin into two unequal parts. Southwest of the confluence of the two Warriors these two parts seem to come together in one common basin by the sinking away of the ridge which separates them higher up.

The Warrior basin includes all of Walker and Winston and parts of Cullman, Morgan, Lawrence, Franklin, Marion, Lamar, Fayette, Tuscaloosa, and Jefferson counties, and will aggregate about 4,955 square miles. The whole