The Collaborative International Dictionary of English v.0.48:

Arles \Arles\, n. pl. [Cf. F. arrhes, Scot. airles. Cf. Earles
   penny.]
   An earnest; earnest money; money paid to bind a bargain.
   [Scot.]
   [1913 Webster]

   Arles penny, earnest money given to servants. --Kersey.
      [1913 Webster]