The inventories of 1873-1907 list it as "A large refracting telescope by Steinheil with object lens of 6-inch (16.2 cm) aperture and 9-foot (260 cm) focal length [Inv. MdS-127], equipped with seven celestial eye-pieces, a helioscope, an auxiliary telescope with 20-line (c. 4.5 cm) aperture. (The helioscope and two Verniers are missing. The instrument is in poor condition and even originally (1874) its mounting was to be considered provisional, being in wood and destined to make the instrument transportable).
Only the painted wooden tube remains today, which carries the support for the mount, in black iron. In 1874, when it was used by the Modenese Pietro Tacchini (1838-1905) - one of the founders of the Società degli Spettroscopisti italiani - for observing in India the transit of Venus across the solar disk, it was fitted with a provisional wooden mount, as reported in the inventory.
At the end of the last century it was installed in a small conical dome, facing south on the terrace of the penultimate floor of the tower of the Specola; the dome can still be seen in photographs taken at the beginning of the century. In the 60s the dome was dismantled to make room for the present elevator. For a short period of time, after 1936, it was used as guide telescope for the 60 cm reflecting telescope at Loiano.
A wooden eyepiece holder box has been found [Inv. MdS-93], bearing the words (handwritten and unclear) Di Stainar, which could be the original box for the telescope accessories.
Von Steinheil, professor of physics and mathematics at Munich, was also a telescope maker, famous for his 3-lens aplanatic system.
E. Engberts (1970), pp. 64, 144.
M. Rajna (1906).
J.A. Repsold (1914), pp. 66-71.