Building a staircase requires mastery of the art of joinery. The thin, regularly spaced vertical grooves on the central core (the ‘lantern’), suggest that this model was used for teaching purposes. In 1770, advice in Description of the Arts and Crafts – one of whose contributors was the master joiner André Jacob Roubo – for staircases with an elliptical plan was to divide the tread supports, core and stringer equally to obtain regular steps. The fact that this is a double staircase adds nothing technically but enhances the aesthetic balance of this model, which could well have been the ‘masterpiece’ of a journeyman carpenter. It joined the collection before 1814, and may have been seized during the French Revolution.