Constructed at the initiative of Peter Leopold of Lorraine in the upper part of Palazzo Torrigiani between 1780 and 1789, the Astronomical Observatory "La Specola" was annexed to the Imperial Regio Museo di Fisica e Storia Naturale. In the intentions of the Grand Duke, the little tower was to be the most important astronomical observatory in Tuscany, and to compete with the great centres of Greenwich and Paris. It was therefore equipped with fine, expensive astronomical instruments, mainly of excellent English fabrication. In spite of this, however, the Florentine "specola" remained without a permanent astronomer until 1807, when Domenico De Vecchi was appointed professor of astronomy of the Lyceum and director of the Observatory. After a further period of stagnation, in 1825 the Frenchman Jean-Louis Pons arrived at the Specola; he was succeeded in 1831 by Giovanni Battista Amici. The latter, who was an outstanding optician, set up an optical-mechanical workshop next to the Observatory, the embryo of the industry later known as Officine Galileo. Amici was succeeded by Giovanni Battista Donati, a distinguished astronomer who promoted the first studies in astrophysics in Florence. Donati also turned his attention to the old, unsolved problem of the infelicitous position of the Florentine observatory. Thanks to him, astronomical research was transferred to the hill of Arcetri.

The octagonal tower of the Observatory contains, in the Stork Room, a fine marble sundial, fabricated by an unknown artisan. On it appears the following inscription: "Linea meridiana ducta in observatorio regii musaei scientiarum florentinii Peter Leopold imperante 1784". It served to mark the hours and the days of the calendar, but is no longer functioning today since the bushing of the gnomic hole is missing.

Lastly, some explanation of its name; it was a ancient custom to call astronomical domes by the name of "Specola", from the Latin specula which means look-out tower, observatory. And so the Florentine Observatory in Via Romana was named "La Specola". However, even after the astronomical observatory had been moved from the tower of Palazzo Torrigiani to the hill of Arcetri, the name "Specola" was still used to designate the building in which the old Observatory and the Museum of Physics and Natural Science had been located. For this reason the present-day Zoological Museum, which remained in the old buildings in Via Romana, is still called "La Specola". The Museum is now engaged in elaborating a project for restoring the ancient astronomical observatory.