to clack wool

from The Collaborative International Dictionary of English v.0.48

Clack \Clack\, v. t.
   1. To cause to make a sudden, sharp noise, or succession of
      noises; to click.
      [1913 Webster]

   2. To utter rapidly and inconsiderately. --Feltham.
      [1913 Webster]

   {To clack wool}, to cut off the sheep's mark, in order to
      make the wool weigh less and thus yield less duty. [Eng.]
      [1913 Webster]