The name of this fantastical mirror comes from its patron, Baron von Gymnich, a powerful figure at the court of Cologne. His coat of arms featured a duck, here transformed into a quirky crowning element for a marshy thicket of ornament. Commissioned for Gymnich’s castle, possibly for a grotto-like room, this mirror exemplifies the most flamboyant aspects of the Rococo style that dominated European interior decoration in the mid-eighteenth century. Restless, curling scrollwork conjures batwings, and plant life. Silvering, and crushed glass or sand, evoke rushing waterfalls. A grotesque masque plays the part of a fountain, streaming water into the pool-like mirror.