has every variety of excellent qualities. The northern districts in 1873 produced 1,500,000 tons, and the eastern margin of the field 1,000,000 tons of semi-bituminous coal. Of the common bituminous coal 9,000,000 tons were mined in that year, chiefly in the Westmoreland and Pittsburgh districts and along the Monongahela and Youghiogheny rivers, for the supply of all the western states by way of the Ohio and Mississippi rivers, for gas making in the eastern cities, and for domestic and manufacturing purposes in the state. This is therefore the greatest of all the coal-producing states; and from its geographical position, its rich endowment of other minerals, and other natural advantages, there is every probability of its continuing to retain this position for a long time. The coal field which covers the eastern part of Ohio is the western border of that of western Pennsylvania. It stretches along the Ohio river from the Mahoning river on the north to near the Scioto on the south, from two to four counties in width, embracing 10,000 sq. m., being nearly as large as that of Pennsylvania, which has 12,774 sq. m. of coal. Along the N. E. border is found a peculiar splint or block coal, which has been used for many years in its raw state in blast furnaces; some small basins of it also occur on the Pennsylvania side of the line. Further south, in the Hocking valley, occurs a coal bed of extraordinary size, measuring in some localities 12 ft. in thickness, and it is said that it can also be used like the block coal.
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| Fig. 5.—Appalachian Formations, Ancient and Modern. |
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References: Modern.—a, the Atlantic sea; b, recent or cretaceous formations; c, granitic and volcanic; d, mesozoic, new red, &c.; e, metamorphic, gneissic, &c.; g, sandstones and limestones of the valley, or the lower palæozoic formations; h, slates and shales of the oil-producing formations; i, sandstones overlying the oil strata, including the old red and the conglomerate; j, the anthracite coal deposits; k, Cumberland coal field; l, l, n, Alleghany coal field; m, Ohio river. The Potsdam sandstone underlies the Auroral limestone, g, and overlies the gneiss, e, which must exist to some extent in the entire basin. The dark vertical trap formations emerge from the granite, and were the means of forming the gneiss. Ancient.—No. 1 corresponds to a, and is the granite seacoast line, forming the volcanic boundary of the ancient sea; 2 is a deep view of the volcanic vent between the granite and the gneiss, which is formed of the vented matter; 3 is the metamorphic or early gneissic sedimentary rocks; 4 corresponds to g, and is the base of the palæozoic; 5 is the bituminous slates of the oil strata, followed by the massive sandstones of the old red, and the subcarboniferous; 6 is the ancient sea, since filled by the sedimentary deposits represented in g, h, i, j, k, l, &c.; 7, 7 is the line of volcanic vents existing in the plutonic or granitic coast line, which extends from Maine to Cuba. The form of the ancient structure is of course ideal, and the two views are thus given together in order to convey an impression of the cause and its effects. |
The production of coal has not been very large in Ohio (about 4,000,000 tons), but from the building of railroads, and the increase of population and manufacturing, the coal trade of the state is rapidly increasing. Maryland has a very small but very valuable basin of bituminous coal near the Baltimore and Ohio railroad, extending from near Cumberland to Piedmont in the western angle of the state. The production in 1873 was 2,674,110 tons, and since the opening of trade in 1842 the total production has been 24,027,786 tons. It is sold chiefly at New York for the use of ocean steamers and other steam purposes, is known as Cumberland coal, and is semi-bituminous; the bed is 14 ft. thick. West Virginia is almost wholly underlaid with bituminous coal, forming a portion of the same field above described in Pennsylvania, Ohio, and Maryland. The upper coal measures, including the Pittsburgh bed, extend over a large space in the N. W. part of the field in this state, along the Ohio river, as far south as the mouth of the Guyandotte. In the northern part of the state these upper coal beds are developed of good size and quality along the Baltimore and Ohio railroad and on the river about Wheeling. There are very fine natural exposures of the lower coal measures on the Kanawha river, from the great falls to Charleston. The display of coal in this district is very remarkable, and it has recently been made accessible by the completion of the Chesapeake and Ohio railroad. There are other very extensive districts in West Virginia, both N. and S. of the
