A lunarium is designed to demonstrate the motions of the Earth and Moon and the phases of the Moon. The base of this example is formed by the wooden box that contains the gearing mechanism. A brass stand is set in a circular hole in the top of the box and supports a candle-holder (a candle flame would represent the Sun) and shield and the arms that support and move the terrestrial sphere and Moon. These are rotated with a brass handle that also protrudes from the top of the box. There is a coloured enamel plaque, surrounded by a brass ring decorated with two small fleur-de-lys, which gives calendar and zodiacal scales and the names of the seasons.

The terrestrial sphere is made of wood with paper gores, and the Moon of ivory. The terrestrial sphere has a labels in French, suggesting that it was made for the French market. A brass plaque on the base is engraved with the maker's name: "George Philip & Son/ 32, Fleet Street, London".