The Collaborative International Dictionary of English v.0.48:

Snarling \Snarl"ing\,
   a. & n. from Snarl, v.
   [1913 Webster]

   Snarling iron, a tool with a long beak, used in the process
      of snarling. When one end is held in a vise, and the shank
      is struck with a hammer, the repercussion of the other
      end, or beak, within the article worked upon gives the
      requisite blow for producing raised work. See 1st Snarl.
      [1913 Webster]