Anthracite

[From Gr. anthrax, charcoal.] (Min.) A variety of mineral coal which is distinguished by its high specific gravity, its semi-metallic lustre, and its burning without emitting smoke, while yielding an intense heat. It differs from bituminous coal in its harder and denser character and greater proportion of carbon, of which that of Pennsylvania contains from 85 to 93 per cent. and that of Wales from 88 to 95 per cent It occurs in strata like other coal and is believed to have had a similar vegetable origin, it having been changed from the bituminous to the anthracite variety by the action of underground heat, occasionally by the influence of intrusive igneous rocks. Anthracite may be of any geological age. The coals of China, which embrace much anthracite, are of Mesozoic age, while in New Mexico, Colorado, Queen Charlotte Island, ., very recent coal has been converted into A. by the action of volcanic outbursts. A. also occurs in Wales and in some other parts of Europe, but far the most productive beds of it are those of Pennsylvania, where it occurs in great abundance and is of the highest industrial importance. The A. region extends through much of northeastern Pennsylvania, covering an area of about 1,700 sq. miles, of which nearly 500 are underlaid by workable coal beds. At Tamaqua there are 21 coal veins whose aggregate thickne is 126 feet, the Mammoth vein being, near this locality, 114 feet thick. At Pottsville there are 28 beds, with 154 feet in thickne of coal. Pennsylvania A. varies in hardne from the semi-bituminous of the western to the very hard Lehigh coal of the eastern portion of the field. Anthracite is the favored domestic coal, wherever obtainable, for its cleanne and freedom from smoke, though in many places it is considered le desirable than bituminous for steam-making purposes. Attempts to mine the Pennsylvania anthracite were made in 1793, but no regular shipments were made until 1820, and it did not come into use for manufacturing purposes until after 1830. The mining and use of it have steadily increased until the product of the Pennsylvania mines has become enormous in quantity and widespread in distribution. In 1895 the total output was 57,999,337 tons, valued at the mines at $78,488,063. See COAL PERIOD and MINERAL COAL. Anthraco's is ( an - thra - ko's is ). [From Gr. anthrax, charcoal and osis , morbid condition.] ( Pathol .) A species of carbuncle which affects the eyelids and globe of the eye. The term is also applied to the "black lung" of coal-miners, an affection induced by an accumulation of carbonaceous particles in the lungs. Sometimes ulceration results from this cause, and the malady is then termed black phthisis.