STEAM, HEATING BY. It has been ascertained that one cubic foot of boiler will heat about 2000 cubic feet, 126 feet each way, to an average heat of about 70° or 80° Fahr. And one square foot of surface of steam-pipe is adequate to the warming of 200 cubic feet, 6 each way. This quantity is adapted to a finished ordinary brick or stone ing. Cast-iron pipes are preferable to all others for the diffusion of heat, the pipes being distributed within a few inches of the floor.
Steam is used extensively for drying muslin and calicoes. Large cylinders are filled with it, which, diffusing in the apartment a temperature of 100° or 136°, rapidly dry the suspended cloth. Expe rience has shown that bright dyed yarns, like scarlet, dried in a common stove heat of 128°, have their color darkened, and acquire a harsh feel ; while similar hanks, laid on a steam-pipe heated up to 165°, retain the shads and lustre they possessed in the moist state. Besides, the people who work in steam-drying rooms are healthy, while those who were formerly employed in the stove-heated apartments became, in a short time, sick ly and emaciated. The heating, by steam,
of large quantities of water, or other li quids, either for baths or manufactures, may be effected in two ways : the steam pipe may be plunged, with an open end, into the water-cistern; or the steam may be diffused around the liquid in the in terval between the wooden vessel and the interior metallic case. The second mode is of universal applicability.
Cooking food, both for man and cattle, is another useful application of steam ; for it is the most effectual carrier of heat that can be conceived, depositing it only on such bodies as are colder than boiling water. Chambers filled with steam, heat ed to about 125° Fehr., have been intro duced, with advantage, into medical practice, under the name of Vapor-baths.