1. \Fur"nace\, n. [OE. fornais, forneis, OF. fornaise, F.
   fournaise, from L. fornax; akin to furnus oven, and prob. to
   E. forceps.]
   1. An inclosed place in which heat is produced by the
      combustion of fuel, as for reducing ores or melting
      metals, for warming a house, for baking pottery, etc.; as,
      an iron furnace; a hot-air furnace; a glass furnace; a
      boiler furnace, etc.
   
   Note: Furnaces are classified as wind or air. furnaces when
         the fire is urged only by the natural draught; as blast
         furnaces, when the fire is urged by the injection
         artificially of a forcible current of air; and as
         reverberatory furnaces, when the flame, in passing to
         the chimney, is thrown down by a low arched roof upon
         the materials operated upon.
   
   2. A place or time of punishment, affiction, or great trial;
      severe experience or discipline. --Deut. iv. 20.
   
   {Bustamente furnace}, a shaft furnace for roasting
      quicksilver ores.
   
   {Furnace bridge}, Same as {Bridge wall}. See {Bridge}, n., 5.
   
   
   {Furnace} {cadmiam or cadmia}, the oxide of zinc which
      accumulates in the chimneys of furnaces smelting
      zinciferous ores. --Raymond.
   
   {Furnace hoist} (Iron Manuf.), a lift for raising ore, coal,
      etc., to the mouth of a blast furnace.
   
   

2. \Fur"nace\, n.
   1. To throw out, or exhale, as from a furnace; also, to put
      into a furnace. [Obs. or R.]
   
            He furnaces The thick sighe from him. --Shak.
   
   

(1.) Chald. attun, a large furnace with a wide open mouth, at the top of which materials were cast in (Dan. 3:22, 23; comp. Jer. 29:22). This furnace would be in constant requisition, for the Babylonians disposed of their dead by cremation, as did also the Accadians who invaded Mesopotamia.

(2.) Heb. kibshan, a smelting furnace (Gen. 19:28), also a lime-kiln (Isa. 33:12; Amos 2:1).

(3.) Heb. kur, a refining furnace (Prov. 17:3; 27:21; Ezek. 22:18).

(4.) Heb. alil, a crucible; only used in Ps. 12:6.

(5.) Heb. tannur, oven for baking bread (Gen. 15:17; Isa. 31:9; Neh. 3:11). It was a large pot, narrowing towards the top. When it was heated by a fire made within, the dough was spread over the heated surface, and thus was baked. "A smoking furnace and a burning lamp" (Gen. 15:17), the symbol of the presence of the Almighty, passed between the divided pieces of Abraham's sacrifice in ratification of the covenant God made with him. (See OVEN.)

(6.) Gr. kamnos, a furnace, kiln, or oven (Matt. 13:42, 50; Rev. 1:15; 9:2).