Source : Webster's Revised Unabridged Dictionary (1913)

Fettling \Fet"tling\, n.
   1. (Metal.) A mixture of ore, cinders, etc., used to line the
      hearth of a puddling furnace. [Eng.] [It is commonly
      called {fix} in the United States.]

   2. (Pottery) The operation of shaving or smoothing the
      surface of undried clay ware.