The Collaborative International Dictionary of English v.0.48:

Rounce \Rounce\ (rouns), n. [Cf. F. ronce bramble, brier, thorn,
   ranche a round, step, rack, or E. round.] (Print.)
   The handle by which the bed of a hand press, holding the form
   of type, etc., is run in under the platen and out again; --
   sometimes applied to the whole apparatus by which the form is
   moved under the platen.
   [1913 Webster]