The quadrant bears the words Hewitt & Son / Makers to the Admiralty / London / n. 2334. On the inside of the case are two references to two repairs done on the instrument: at Genoa in 1895 and at Marseilles in 1898 (change of oil and mechanical check).
It has gimbal suspension and wound up lasts for 7 days. In 1993 it was restored by Leano Colliva of Bologna when the broken wind-spring was replaced.
T.N. Clarke, A.D. Morrison-Low, A.D.C. Simpson (1989), pp. 156 e 159.