SULPHURATION, is the process by which woollen, silk, and cotton goods are exposed to the vapors of burning sul phur, or to sulphurous acid gas. In the article STRAW-HAT MANUFACTURE, this operation has been referred to. Sulphnring-rooms are sometimes con structed upon a great scale, in which blankets, shawls, and woollen clothes may be suspended freely upon poles or cords. The floor is flagged with a sloping pave ment, to favor the drainage of the water that drops from the moistened cloth. The iron or stoneware vessels, in which the sulphur is burned, are set in the cor ners of the apartment. The windows and the entrance door must be made to shut hermetically close. In the lower port of the door there should be a small open ing, with a sliding shutter, which may be raised or lowered by the mechanism of a cord passing over a puffy.
The aperture by which the sulphurous acid and exotic gases are let off, in order to carry on the combustion, should be somewhat larger than the opening at the bottom. A lofty chimney carries the
noxious gases above the building, and diffuses them over a wide space.
When the chamber is to be used, the goods are hung up, and a small lire is made in the draught-stove. The proper quantity of sulphur being next put into the shallow pans, it is kindled, the en trance door is closed, as well as its shut ter, while a vent-hole near the ground is opened by drawing its cord, which passes over a pulley. After a few minutes, when the sulphur is fully kindled, that vent-hole must be almost entirely shut, by relaxing the cord • when the whole apparatus is to be let alone for asuflicient time.
The object of the preceding precautions is to prevent the sulphurous acid gas escaping. This is secured by closing the door imperfectly, so that it may admit of the passage of somewhat more air than can enter by the upper seams, and the smallest quantity of fresh air that can support the combustion.