Copernican planetarium model to illustrate terrestrial and lunar revolutions around the Sun. Attributed to Charles-François Delamarche. The device can be hand-operated by means of a gear system to simulate the motions of the celestial bodies with varying degrees of approximation. Delamarche produced similar models in the early nineteenth century. There is a similar instrument in the collection of the Osservatorio Ximeniano, also in Florence.