Kiln
An oven or stove which may be heated for the purpose of drying, hardening, or burning anything. Kilns are used for roasting or calcining iron ores, with the view of expelling water, sulphur, and volatile or other matters which under the influence of heat, or the combined action of heat and atmospheric air, are capable of volatilization, and to free the ore from these constituents and leave it porous; in which condition it is more readily acted upon by the flame and gases of the blast-furnace. See CALCINATION; WEATHERING ORES.