558 ANTHRACITE dip of the strata, the change of strike incident thereto, and the general irregularities of both coal bed and accompanying strata, would be denominated faults in the great bituminous fields of the United States or England. The use of anthracite as a common fuel is recent. It was long supposed to be an inferior kind of coal, and the creation of an earlier period than the true carboniferous ; even now there are a few professional men who adhere to this ex- ploded theory. The first attempts to use it as fuel were as a substitute for wood or the free- burning bituminous coals, where a draught of air through the mass is not absolutely necessary, as in the case of anthracite. On account of this difficulty of ignition, and the prevailing igno- rance in regard to the best methods of using it, anthracite was slow to be appreciated. In 1813 it was considered inferior in Wales, and was but little used for any purpose ; and though known and tested as a valuable fuel in the United States arsenal at Carlisle, Pa., in 1776, and by smiths on the Susquehanna generally even at an earlier date, it was only in 1812 that it was successfully used in Philadelphia, and there the mode of burning it was discovered by accident. The general trade only commences with a few tons in 1820. (See table.) At first the increase of consumption was slow, but so soon as its use and advantages became generally understood, it assumed the first place in the list of combus- tibles. For household purposes it is preferred not only on account of its cleanliness and the absence of smoke and the peculiar odor of bitu- men, but also on account of its durability and long continued and uniform heat. For war steamers, where the conspicuous smoke of bi- tuminous coal is exceedingly objectionable dur- ing hostile movements, anthracite has been fully tested and found superior, not only because of the absence of smoke, but of its good steam- producing qualities, its duration at high tem- peratures, and the consequent maintenance of a steady uniform steam power. For the eco- nomical combustion of anthracite a strong draught rather than an abundant supply of air is required. In common use, however, where chimney draught is ordinarily employed, these two requirements are antagonistic, as far as economy is concerned. To obtain a draught strong enough to pass sufficient air through the coals, a high and hot chimney is required, which absorbs and carries off the largest pro- portion of caloric from furnaces as commonly constructed. The coal is rarely burned to carbonic acid by direct combustion in this man- ner, but rather to carbonic oxide, which is lost, and more than half the fuel is thus wasted. The first or direct combustion, producing car- bonic oxide, generates about 1300 C., while the carbonic oxide is capable of producing over 2100 C. of heat in addition ; but when anthra- cite is burned to carbonic acid direct in properly constructed gas-burning furnaces, the tempera- ture is increased to 2400 C. The volume of heat or total heating effect is, however, in favor of carbonic oxide as fuel, and it would be much more economical and generally useful to con- vert anthracite or bituminous coal to carbonic oxide before using it as a fuel. In the blast furnace, however, where anthracite is preemi- nent, the coal must be used in its solid condi- tion ; but here, in well constructed furnaces, the total heating effect of the coal is utilized. But it cannot be claimed that anthracite is a superior fuel for all purposes, because bitumi- nous coal can be used in all cases, while an- thracite cannot be used in the present state of the arts for the production of illuminating gas. Where a long hot flame is required, as in pud- dling furnaces, hydrogenous coal is more avail- able ; and for welding heats, where hollow fires are desirable, the latter class of coal is also used. But under proper combustion, anthracite, an the purest form of carbon Available for fuel, will yield a higher temperature than any other kind of fuel. The earliest record of the use of anthracite for the production of iron is in 1826, when a small furnace built under the direction of Messrs. White and Hazard of the Lehigh coal company, near Mauch Chunk, Pa., was tried with anthracite and cold blast; but, though several pigs of anthracite iron were made, the furnace chilled and the attempt proved a failure. Several other experiments were made both on the Lehigh and the Schuylkill, which were successful in the production of anthracite iron, but failed of practical results. Attempts had been made prior to this time to use anthra- cite for the production of iron in the blast fur- naces of Wales ; but nothing definite is given in regard to the date of these experiments until after the introduction of the hot blast by Neil- son in 1831, or its more general use in 1883. Mr. David Thomas then conceived the idea of using anthracite with hot blast, and induced his employer to try the experiment. A coke fur- nace was accordingly altered during 1836, and provided with a hot-blast arrangement ; and in February, 1887, anthracite iron was success- fully made in Wales for the first time. In 1837 the Lehigh coal and navigation company, at- tracted by the success of the Welsh furnace, sent one of their directors to Wales, who en- gaged Mr. Thomas to start a furnace on the Lehigh, which was successfully accomplished in June, 1889. The " Pioneer Furnace " at Potts- ville, built by William Lyman of Boston, had been put in blast a few months previous, after the directions of Mr. Thomas. For this Mr. Lyman was awarded a premium of $5,000 which had been offered by Burd Patterson of Pottsville and Nicholas Biddle of Philadelphia for the profitable production of anthracite iron, and which was paid at a banquet given at Mt. Carbon early in 1840. Since then the Thomas and Crane iron works on the Lehigh have grown to mammoth establishments, and are now capable of producing 100,000 tons of pig iron per annum ; and the total annual production of anthracite iron has now (1873) reached 875,000 tons.
