The Observatory of Arcetri owns a small collection of astronomical instruments. The most valuable objects are on display in a few glass cabinets in the Amici Pavilion, where they can be admired during the Observatory's open nights and other activities for the public. Other instruments of historical/scientific interest are located in a cabinet inside the main Observatory building, where they can be visited on request. The collection includes instruments used in the old Observatory of Florence (the Specola, operating between the end of the eighteenth century and 1870) and those purchased later for the Arcetri Observatory, which replaced the Specola.
Since the earliest days of the Observatory (inaugurated in 1872), the need for room for research and the presence in the old building of the Specola of the "Museo degli antichi strumenti di fisica e astronomia", made it so that obsolete and useless instrument were moved to the musum collections (later inherited by the Museum of the History of Science, renamed Museo Galileo in 2008).
The moving was facilitated by the participation of the Observatory directors G. Abetti and G. Righini to the museum administrations. A symbolic case is that of the two Amici telescopes, whose tubes are now on display at the
Museo Galileo, while the objectives - used until the end of the 1960s - are still in Arcetri. Therefore, many instruments originally part of the equipment of the Observatory are now in display in the Museo Galileo. The Observatory collection also includes a gallery of busts, among which the marble busts of the founder of the Arcetri Observatory, G. B. Donati, and of his assistent D. Cipolletti (works of U. Lucchesi and L. Cartei, respectively).