This museum in Hôtel de Donon brings together oil paintings, pastels, sculpture, objets d’art, jewellery, porcelain and furniture from the 18th century assembled by Ernest Cognacq (1839–1928), founder of La Samaritaine department store, and his wife Louise Jay.

Although Cognacq appreciated little of his collection, boasting to all who would listen that he had never visited the Louvre and was only acquiring collections for the status, the artwork and objets d’art give a pretty good idea of upper-class tastes during the Age of Enlightenment. Temporary exhibitions command admission fee.