puddling

Purification of impure metal, especially pig iron, by heating and stirring in an oxidizing atmosphere.

Compaction of wet material, such as clay, in order to make a watertight paste.

In hydraul, engin., the operation of working plastic clay behind piling in a cofferdam, the lining of a canal, or in other situation, to prevent the penetration of water; also, the clay or other material used in this operation.

The operation of transforming pig-iron into wrought-iron in a reverberatory furnace.

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.