The instrument consists of four rectangular tubes containing two small telescopes: the eyepieces are at the larger end, the objectives at the smaller. All the tubes are made of wood and painted black on the inside. The largest tube is covered with black grained leather. The others are covered with green leather with gold tooling, and bear the Medici coat of arms in the center. On the edges is the image of a cherub, the maker's symbolic signature. The two inner tubes, in parchment, are now missing some parts. The compound eyepiece comprises three lenses. The magnification is 15. This binocular telescope was first described in the work by the Capuchin friar Chérubin d'Orléans, La dioptrique oculaire [Ocular dioptrics], (Paris, 1671). The presence of the Medici coat of arms indicates that Chérubin himself made the instrument for Cosimo III de' Medici, probably in the 1670s. Provenance: Medici collections.