Sharp ME. aan good Fig. 1 Locust Mt tion of the coal, instead of being conducted by levels driven into the side of the hills, is effected by means of inclined shafts following down the course of the beds from the surface, or by vertical slopes sunk so as to cut them at considerable depths. The arrangement of the strata in its general features is represented in the accompanying wood cuts. Fig. 1 is a section from Sharp Mountain, on the south side of the Mauch Chunk summit mine, across this great body of coal, and the higher coal-beds of the formation repeatedly brought to the surface by their changes of dip, to Locust Mountain, which bounds the basin on the north. Fig. 2 is a section across the same basin at Tamaqua, six miles west from Mauch Chunk mine. In this section it is seen how the coal-measures are separated into basins by the lower rocks coming up to the surface and forming anticlinal axes. Fig. 3 represents the position of single beds, as they occur among the slates and sandstones, and the manner in which they are sometimes reached by means of a tunnel driven in from the base of the hill. The curved portion of the coal at the top is formed by the coal-beds at their outcrop becoming disintegrated, and their fragments and decomposed smut being spread down the slope of the hill. The Roman numerals, "IX," "X," "XI," "XII," in fig. 2, designate the lower formations of rock, known respectively as the red sandstones (corresponding to the "Old Red Sandstone"); a series of gray sandstones; one of red shales; and Lastly, the conglomerate. The dotted lines above and below the section mark the continuity of the conglomerate beneath the base of the section and its original course above the present surface before this portion had been removed by diluvial action. The other Mohanoy Pottsville Coal basin Fig. 2 Broad Mtn Second Min formations obviously accompany the glomerate with similar flexures. IX The same cause, that threw the strata into their inclined and contorted positions, no doubt changed the character of the coal by dispelling its volatile portions, converting it in fact into coke, while the pressure of the superincumbent beds of rock pre Alabama.. vented the swelling up of the material, as Virginia.. AMOUNT OF AVAILABLE COAL. In estimating the quantities of workable coal in any district, several points are to be taken into consideration besides the amount of surface covered by the coal-measures and the aggregate thickness of all the beds they contain. Out of the total number of coalbeds, there are more or less of them that must be excluded from the estimate, on account of their being too thin to work. The great depth at which the lower beds in the central parts of the Appalachian coal-field lie must probably prevent their ever being worked; but for this no allowance is ever made in the estimates of quantities of coal. The most careful and complete computations of this nature which have been made are those of Professor H. D. Rogers, and of Mr. Bannan in the Coal Statistical Register for 1871. From these sources we obtain the following estimates: EXTENT OF COAL-FIELD IN The several stATES POSSESSING THE COAL FORMATION. Ohio..... Sq. miles. Missouri.. 15,900 13,700 3,700 6,130 170 6,700 40,000 13,350 24,000 21,329 84,000 80,000 12,597 Indian Territory.. 40,000 30,000 20,000 20,000 20,000 74,000 100,000 In the anthracite basins of Pennsylvania the number of workable beds varies from 2 or 3 to 25, according to the depth of the basin; the average number is supposed to be 10 or 12. The maximum thickness of coal is in the Pottsville basin, and amounts to 207 feet. Rejecting the thin seams, the average thickness in the south anthracite field is reckoned at 100 feet; in the middle or north field at about 60 feet; and the general average of the whole, 70 feet. The maximum thickness of the 15 or 16 coal-beds of the central part of the Appalachian coal-field is about 40 feet, but the average of the whole basin is considered t be 25 feet. The basin extending over Illinois and into Indiana and Kentucky, contains in the last-named state 16 or 17 workable beds, with a maximum thickness of about 50 feet. The average over the whole area is supposed to be 20 or 25 feet. The following estimates of the British coal-fields are introduced for comparison. Extending these computations to Belgium and France also, the result of calculations of 550 available coal supply, in 1870, are as follows: RELATIVE AMOUNT OF COAL IN THE SEVERAL GREAT COAL-FIELDS OF EUROPE and AMERICA. Belgium (assuming an average thickness of about 60 feet of coal) contains about.... 36,000,000,000 Pennsylvania (averaging 25 feet thickness) contains.. France (with same thickness) contains about.. The British Islands (averaging 35 feet thickness) contain nearly. The great Appalachian coal-field (including Pennsylvania, averaging 25 feet). 1,387,500,000,000 All the productive coal-fields of North America (with an assumed thickness All the coal-fields of Europe..... The following table contains the yearly | States, from the commencement of the trade returns of the coal product of the United in 1820: ..... ..... ..... 22,122 22,122 22,122 23,195 34,525 84,52 12,401 38,243 22,830 30,435 80,433 d 4,090 37,384 d 869 7,228 7,228 d30,156 18,336 d25,999 25,645 25,645 18,417 60,538 42,205 35,665 35,663 10,020 83,712 23,174 40,257 40,257 4,502 103,691 19,979 82,302 82,302 d7,955 10,818 6,127 45,393 45,393 13,031 157,476 47,658 Total consumption of Anthracite and Bituminous Coal in the Aggregate of Bituminous mined in other portions of the United States, not included in this table. 2,176,541 173,021 516,676 175,039 8,500,000 22,000,000 12,110,923 1,149,060 132,438 8,000,000 1866 149,801 70,112 53,648 1,137,881 265,720 736,153 21,800,000 343,178 1,079,331 643,294 3,399,787 560,991 15,455,584 3,334,531 149,273 8,500,000 1867 165,394 127,642 48,118 1,349,869 244,412 735,669 25,500,000 458,153 1,193,822 482,325 521,305 3,650,562 250,775 15,866,777 411,193 286,758 9,000,000 26,800,000 490,508 17,545,08 1,779,309 277,063 9.500,000 29,200,000 946,860 18,308,31 763,230 583,737 10,000,000 31,800,000 9,607,448 1,965,954 873,618 11,812,975 3,640,480 11,863,412 5,373,658 17. 237,070 10,437,102 47,720,6161 248,257,171 TRANSPORTATION OF COAL TO MARKET. The first anthracite from the Schuylkill mines was brought to Philadelphia in wagons. The navigation of the river and canal was hardly practicable for boats previous to the year 1822; and though from that year anthracite was conveyed to Philadelphia and the trade continued to increase, it was not until 1825 that a large amount of coal could be transported by this route. The effect of these improvements was experienced in the transportation of 6,500 tons in 1825; in 1826 it increased to 16,763. As for successive years the trade steadily and rapidly increased in importance, the capacity of the canal proved at last insufficient for it, and the Reading railroad was laid out for its accommodation, and constructed with a uniform descending grade from the mining region at Pottsville to the Delaware river. It was opened in 1841, and proved a formidable competitor to the Schuylkill canal, but the increasing trade has surpassed the capacity of both these routes. Other lines have been constructed, till now there are six or seven railroads engaged almost exclusively in the transportation of the anthracite and semianthracite coals from the mines. As seen by the table, the first shipments of anthracite were from the Lehigh region, two years before any were sent from the Schuylkill. The transportation was effected by arks or large boxes built of plank, and run down the rapid and shoal river with no little risk. To return with them was impracticable, nor was this desired, for the arks themselves were constructed of the product of the forests, which in this form was most conveniently got to market. As the coal trade increased in importance, the Lehigh Coal and Navigation Company, to insure greater facility in running the arks, constructed dams across the shoaler places in the river, by which the water was held back, thus increasing the depth above. As the arks coming down the river reached one of these dams, the sluice gates were opened and the boats descended to the next dam below. At first two arks were connected together by hinges at the ends; subsequently more were thus joined together, till they reached nearly 200 feet in length. In 1831 the slack-water navigation of the Lehigh was so far perfected, that it was used by canal boats ascending and descending through regular locks. Up to the year 1827 the transportation of anthracite to Mauch Chunk, nine miles from the mines, was by wagons. The Mauch Chunk road, completed in May, 1827, was made with a descending grade, averaging about 100 feet to the mile, so that the loaded cars ran down by gravity. Each train carried down with it in cars appropriated to this use the mules for drawing the empty cars back; and it is stated that after the animals once became accustomed to the routine of their duties they could never be made to travel down the road if accidentally left behind. The trade before many years outgrew these increased facilities of transporting the coal, and it was found essential to return the empty cars by some more economical method. On account of the heavy upgrade, locomotives, it was concluded, could not be advantageously employed, and hence a system of inclined planes and gravity roads was devised, by which the cars hoisted by stationary power to the summit of the planes and thence descending the gravity roads might be returned to the mines. In the accompanying sketches a part of this arrangement of roads is exhibited. The high hill called Mount Pisgah, above the village of Mauch Chunk, is the terminating point at the Lehigh river of the long ridge called Sharp Mountain. The lower road seen in the sketch is called the loaded track. The cars come by this from the mines, and being let down the inclined plane at its terminus, their loads are discharged into the great bins over the edge of the river. They are then hauled a short distance to the foot of the long plane that reaches to the summit of Mount Pisgah, and by the stationary steam engine are drawn up in about six minutes to an elevation 850 feet above that at the foot. The length of this plane is 2250 feet. From its summit the empty cars run down the inclined road constructed along the south side of the ridge, and at the distance of six miles, having descended about 300 feet, they reach the foot of another inclined plane at Mount Jefferson. This plane is 2070 feet long, rising 462 feet. The ascent is accomplished in three minutes, and from the top another gravity road extends about a mile, descending 44 feet to the Summit Hill village. From this point branch roads lead to the different mines in Panther Creek valley, and all meet again in the loaded track road by which the cars return to Mauch Chunk. The transportation of coal from Mauch Chunk was conducted by the river and canal |