Page:The American Cyclopædia (1879) Volume I.djvu/591

 ANTHRACITE 555 RAILROADS BUILT EXCLUSIVELY OR MAINLY FOR THE TRANSPORTATION OF ANTHRACITE. NAMES. LENGTH IN MILES. Cort. Sidings and Branches. Double Track. Main Track. Philadelphia and Reading (total length, Including leased lines, 1,266 m.) 158 23 26 8*. 2X 151 85 82 75 260 115 45 105 16# 6 101 75 S3 104 45 7 23 8% 29 7 2# 100 54 11 28 5tf $38,677,075 18.825,000 8.884806 12,041,731. 1,152,968 160,500 19.230,730 8,000,000 8.000,000 5,281,883 1,850,600 891,608 416,187 823,875 8.905,600 203,259 282,815 2,000,000 1,283,490 576,840 1,569,450 160,500 r 125 ? ? 10 y 19 9 100 2 9^ 10 9 3 '86* ? 15 f j* "S" Little Schuylkill Mill Creek and Mine Hill Mine Hill and Schuylkill Haven McCauley Mountain Railroad Totals. . 520# 538% 1,231^ $128,167,912 general formation of the beds resembles that of the lower irregular beds or pockets in the south- ern Pennsylvania field below A ; and the im- pure, graphitic character of the coal is the same. In both the coal exists hi " nests " rather than beds, sometimes 10 and even 20 ft. thick, but often not as many inches, and frequently they disappear entirely. In the Pennsylvania anthracite fields the palaaozoic sedimentary stra- ta, between the coal measures and the igneous rocks, are between 5 and 7 m. in thickness; while the sedimentary strata below the New England field are comparatively thin, and so highly crystallized or metamorphosed by heat as to have been mistaken by the early geologists for the gneissic rocks. Dr. Edward Hitchcock, however, maintains that the whole region, em- bracing not less than 500 sq. m., is a true coal field, which has experienced more than ordi- nary metamorphic action both mechanical and chemical. He says: "The mechanical forces seem to have operated on the strata containing the coal in a lateral direction, so as not only to raise them into highly inclined positions, but also to produce plaits or folds. . . . The chemical metamorphoses which these rocks have experi- enced consist mainly in such effects as heat would produce." Prof. Silliman, Prof. Jackson, and Dr. Hitchcock have given favorable opin- ions in regard to the probable future produc- tiveness of this field and the commercial value of the coal. The developed coal beds are three in number. Their dimensions are variable, but may be averaged from 3 to 7 ft. respective- ly, when in their best condition. At Ports- mouth the principal bed has been mined by a slope of 600 ft. in length, inclining at 30 to 35, to a vertical depth of 300 ft. ; from the and Essex and the Central railway of New Jersey, which were not built exclusively as coal transportation lines. bottom of which gangways were driven 1,000 ft. in length on the strike of the bed, which increased and decreased from 16 inches to as many feet. Mining operations have been at- tempted in many localities in this field, but all have ended in failure, owing to the disappear- ance or faulty character of the coal beds. The amount of coal mined from the field has been insignificant, and no trustworthy statistics have been recorded. The product, however, when pure and solid, compares favorably with the Pennsylvania anthracite, though usually the best of it contains more water, graphite, and earthy impurities. It is probable that deep and well conducted mining operations will eventually develop this field in a remunerative manner. The diamond drill can now be used before incurring the cost of pits and mining operations, and it may reasonably be anticipated that purer coal and more regular beds will be found at greater depth. The Virginia anthra- cite field, which may be appropriately termed the New river coal field, in Montgomery and Pulaski counties, in S. W. Virginia, consists of two narrow, parallel basins on Price's and Brush mountains. Price's mountain is a nar- row, short synclinal ridge, which rises in the Silurian limestones of the great valley range, and is part of the watershed between the James and New rivers. In this ridge the coal is en- closed as a narrow trough or basin, with an eastern dip of 30, while the true western dip is inverted and dips E. at an angle of 80 or 85. Thus the bottom slate of the lower bed is the roof of the upper bed, and the basin may be generally represented by an Italic capi- tal V ; but the force which tilted and folded the strata in this inverted manner distorted the coal measures and crushed and ruined a large part of the coal, while slips and other forms of fault render the operations of mining
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 * This table is from official sources, excepting the Morris