Puddling

n.
  1. (Hydraul. Engin.) The art or process of converting cast iron into wrought iron or steel by subjecting it to intense heat and frequent stirring in a reverberatory furnace in the presence of oxidizing substances, by which it is freed from a portion of its carbon and other impurities.
    1. The process of working clay, loam, pulverized ore, etc., with water, to render it compact, or impervious to liquids; also, the process of rendering anything impervious to liquids by means of puddled material.
    2. Puddle. See Puddle, n., 2.
    Puddling furnace ,
    a reverberatory furnace in which cast iron is converted into wrought iron or into steel by puddling.