Trompe l'oeil (French for 'deceive the eye') is an art technique that uses very realistic imagery to create the optical illusion that the object depicted is actually three-dimensional. In this case, the painting itself is set into an actual door, and the painted violin appears to hang from a real metal peg on the door itself.
The painting is thought to have been at Devonshire House in Piccadilly, London, and was rescued from the fire that destroyed the house in 1733. It was then brought to Chatsworth, where it was seen by Horace Walpole in 1760.
