The Collaborative International Dictionary of English v.0.48:

Soldering \Sol"der*ing\,
   a. & n. from Solder, v. t.
   [1913 Webster]

   Soldering iron, Soldering tool, an instrument for
      soldering, consisting of a bit or bolt of copper having a
      pointed or wedge-shaped end, and furnished with a handle.
      [1913 Webster]