FUEL, ARTIFICIAL. Coal, in its natural state, consists principally of bitumen, carbon, and some earthy matters. All fuel contain substances possessing bitu minous and carbonaceous properties. Various compounds have been brought forward from time to time, some of them patented, to produce artificial fuel. All those compounds have been combina tions of substances of a carbonaceous and bituminous nature, capable of gene rating inflammable gas and sustaining combustion. Among the first compounds was refuse coal dust, with pitch, which was capable of producing an intense heat. A patent was taken out in London, in 1800, by a Mr. P. Davy, for an artificial fuel, to burn without smoke or sulphur ous smell. It was composed of sea coal dust mixed with charcoal, tanners' bark, and saw-dust. The materials were mix ed together wet, placed in a kiln and slightly cooked, care being taken not to use too high a temperature. Another artificial fuel was to place upon a shelf, above the fire, a quantity of chalk, or lime, which becoming heated from the combustion of the coal below, concen trated the heat for a long time. Another plan was to bake bituminous and anthra cite coal together, to produce a very last ing coke. The proportions were one third of the bituminous. Another plan was that of a Mr. T. Sunderland, who took out a patent for a compound of gas tar, clay, saw-dust, tanners' bark, and refuse dyewood ; all were mixed toge ther, formed into cakes, and dried by any artificial heat. Another compound, and patented too, was saw-dust, spent bark, coke, cinder ashes, and clay, re duced to powder, mixed, cut and dried into cakes, and then dipped into coal tar, or grease, and afterwards dried. An other compound was peat, clay, nitre, alum, linseed and resin, all ground in a mill and pressed into moulds, like bricks, and afterwards dried in the sun. An
other, and an ingenious plan, to harden peat, or swamp earth, was to mix it with powdered coal, or powdered brimstone, to break up the fibres and deprive the peat or swamp earth of its water, after wardspressing it and making it into hard blocks. Another compound, by a Mr. Stirling, patented in England, was to mix pulverized coal with tar and clay. All were intimately mixed together, moulded into blocks and dried, and then they were excellent in shape for stowage. The great object of the producers of arti ficial fuel has been to make it in such a shape that it would be easily stowed away for sea voyages, but the expense always exceeded the benefits. We might enumerate a great number of compounds of the above nature, varying but little from one another, but which constitute the subjects of no less than twenty-one patents, recorded in the London Reper tory of Arts, and in the List of American Very ery favorable accounts are given of using the gas-tar along with spent-tan bark, in the gas-works, to heat the retorts. A patent was taken out in 'Washington, last year, for the compress ing of coal dust into fuel. Another kind is made at Newton's Corners, near Al bany, N. Y., by grinding swamp muck in a pug mill, then submitting it to a very severe pressure, and afterwards drying it. It is represented to burn well.
We know of no kind of fuel, taking it for all in all, that can equal the anthra cite. It is compact and cleanly, good qualities certainly ; but it has another, viz., great and enduring calorific qualities. Bituminous coal is good fuel, but very uncleanly, for domestic use especially. One thing can make its use more agree able, namely, to burn the smoke. This can be done by injecting fine jets of air on the top of the coals.