The hands. In French argot hands are called harpe, which is a contracted form of harpions; and harpion is the Italian arpione, a hook used by thieves to pick linen, etc., from hedges. A harpe d'un chien means a dog's paw, and “Il mania très bien ses harpes” means he used his fingers very dexterously.
“Rosencrantz. My lord, you once did love me. Hamlet. And do still, by these pickers and stcalers.” —