Читать книгу Description of the Process of Manufacturing Coal Gas. For the Lighting of Streets Houses, and Public Buildings онлайн

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The usual denomination by which the second class of coal is known in the London market, is that of strong burning coal. The following varieties are sufficiently known, Russel’s Walls-End; Bewick’s and Craister’s Walls-End; Brown Walls-End, Wellington Main, Temple Main, Heaton Main, Killingsworth Main, Percy Main, Benton Main, and some varieties of the Swansea coal.

The smaller kinds of coal of this class are preferred by smiths, because they stand the blast well. They make a caking fire so as to form a kind of hollow, space or oven, as the workmen call it. Some varieties abound in pyrites, and others are intersected with thin layers of slate and lime-stone. They require more heat for being carbonized than the first class, and the fluid obtained from it by distillation, contains a considerable portion of carbonate, sulphate, and hydrosulphuret of ammonia. They are well calculated for the production of coal gas; the coke which they produce is not very brittle, and will bear moving from place to place, without crumbling into dust.