CHAPTER XII
COAL AND PETROLEUM
The economic history of nearly every country that has achieved eminence in modern times dates from its use of coal and iron; and indeed the presence of these substances in workable deposits means almost unlimited power. The present era is sometimes called the Age of Steel, but the possibilities of producing steel in enormous quantities, at less than one-fifth its price at the beginning of the nineteenth century, depended mainly upon the use of mineral coal instead of charcoal in its manufacture.
Coal consists of accumulations of vegetable matter that were formed in prior geological ages. Under the action of heat and moisture, and also the tremendous pressure of the rock layers that afterward covered them, the vegetable matter was converted to mineral coal.
The aggregate coal-fields of the United States are not far from two hundred thousand square miles in extent, but of this area not much more than one-half is workable. In Europe there are estimated to be about one hundred thousand square miles of coal-lands, of which about half are productive at the present time. Of this Great Britain has 12,000 square miles, Spain 4,000, France 2,000, Germany 1,800, and Belgium 500. In Canada there are about 20,000 square miles of coal-land; a part of this is included in the Nanaimo field on the Pacific coast, but the most important are the Nova Scotia beds, which form about the only supply for the British naval stations of America. China has extensive coal-fields.
In character coal is broadly divided into two classes—anthracite or hard, and bituminous or soft, coal. Anthracite coal occurs in folded and metamorphic rocks. It is hard and glassy, and does not split into thin layers or leaves. The beds have been subjected to intense heat and pressure, and the coal has but a very small amount—rarely more than five per cent.—of volatile matter; it burns, therefore, with little or no smoke and soot, and on this account is very desirable as a fuel in cities. Two areas in Colorado and New Mexico produce small quantities of pure anthracite; practically all the commercial anthracite comes from three small basins in Pennsylvania. In quality it is known as "red ash" and "white ash," the former being the superior.
The yearly output of the anthracite mines is upward of fifty-five million long tons a year, or somewhat less than five million tons per month. In winter the rate of consumption is somewhat greater than that of production. A shortage in the summer production is therefore apt to be keenly felt in the winter. Before shipment to the market the coal is crushed at the breakers, sorted in different sizes, and washed.
Most of the anthracite coal-mines are owned by the railway companies centring at New York and Philadelphia, or else are operated by companies controlled by the railways. About one-fourth of the output is produced by independent operators who, as a rule, sell their coal to the railway companies. The Reading, Pennsylvania, Central of New Jersey, Lackawanna, Lehigh Valley, Ontario & Western, Erie, and Delaware & Hudson are popularly known as "coalers" because the larger part of their eastern business consists in carrying anthracite coal.