Coke, is fossil-coal charred, or or having undergone a proce similar to that by which charcoal is made. By this operation, coals are divested of their humidity, their acid liquor, and part of their fluid oil. They are principally used, where it is necessary to excite intense heat, as for the smelting of iron ore, and for processes in which the acid and oily particles would be detrimental, as in the drying of malt.

CoKe-oven is a kind of furnace, of a circular structure, erected for the purpose of converting coal into coke. Such ovens may, however, at the same time be applied to other purposes. On this account, a pa-tent was granted to the Right Hon. Henry Seymour Conway, in June 1789, for his method of adapting, or conveying the heat arising from the fire of coal, em-ployed in coke-ovens, for working steam-engines, baking bread, etc. calcining and fusing ores and metals, also for warming rooms, etc. heating water for baths, and for many other useful purposes, by which means the expence of the coal or other fuel is entirely, or in the greatest part, saved.

The leading principle of this patent appears to be the constructing of flues both beneath and on the sides of the oven ; in which registers are inserted. By means of these, the heat is conveyed to the steam-engines, baking-ovens, etc. which are built upon and against the sides of the coke-ovens, and may be increased or diminished at pleasure, by opening or shutting the registers; the same fire serving both to burn the coke, and to communicate the requisite degree of heat.