The Collaborative International Dictionary of English v.0.48:

Pitman \Pit"man\, n.; pl. Pitmen.
   1. One who works in a pit, as in mining, in sawing timber,
      etc.
      [1913 Webster]

   2. (Mach.) The connecting rod in a sawmill; also, sometimes,
      a connecting rod in other machinery.
      [1913 Webster]