Source : Webster's Revised Unabridged Dictionary (1913)

Pyrography \Py*rog"ra*phy\, n. [Pyro- + -graphy.]
   A process of printing, ornamenting, or carving, by burning
   with heated instruments.

Source : WordNet®

pyrography
     n : the act of producing drawings on wood or leather by using
         heated tools or a fine flame