to beat a parley

from The Collaborative International Dictionary of English v.0.48
Parley \Par"ley\, n.; pl. {Parleys}. [F. parler speech, talk,
   fr. parler to speak, LL. parabolare, fr. L. parabola a
   comparison, parable, in LL., a word. See {Parable}, and cf.
   {Parliament}, {Parlor}.]
   Mutual discourse or conversation; discussion; hence, an oral
   conference with an enemy, as with regard to a truce.
   [1913 Webster]

         We yield on parley, but are stormed in vain. --Dryden.
   [1913 Webster]

   {To beat a parley} (Mil.), to beat a drum, or sound a
      trumpet, as a signal for holding a conference with the
      enemy.
      [1913 Webster]
    

[email protected]