Page:Popular Science Monthly Volume 38.djvu/471

Rh the idea embodied in the walking-beam blowing-engine, and is very far from adequately representing the latest exemplification of that idea, as carried out in the colossal machines employed to blow many of the largest modern furnaces.

There is great variety in the construction of blast-heating apparatus, but it can be comprehensively described as consisting of



two well-defined types: (1) those forms in which the air is heated by passing through hot iron pipes, inclosed in a brick chamber or "oven"; (2) those forms in which the blast is heated by actual contact with red-hot masses of brick-work inclosed in air-tight chambers. Fig. 35 is a vertical longitudinal section, and Fig. 36 a vertical transverse section, of one of the best of the many forms of the first-named type of "hot-blast stove." This construction of "stove" was the invention of John Player, of England, who introduced it to the notice of American iron-masters in 1807; and the first "Player stove" in the United States was erected at the anthracite furnace of J. B. Moorehead & Co., at West Conshohocken, Pa. Before Mr. Player came to America it had been the usual though not universal practice to place the gas-fired "hot-blast stoves," as well as steam-boilers, on the same level as the top of the furnace, but in all the furnaces erected by him he placed the "hot-blast stoves" and the boilers on the ground, and brought the gas down to them in a large pipe or "down-comer" as it was called.