60 x 64.5 x 18
Steel and copper
INDEX 1788 : C.III.240
Billanx quaedam ocularis accuratissima, quae adhibetur praesertim ad indicandas gravitates solidorum immersorum in fluida.
Very precise ocular balance, mainly designed to indicate the weight of solids immersed in a liquid.
In dalla Bella's time, in the Gabinete de Física, there was a set of five machines for the study of the impulsion force exerted by liquids on bodies immersed in them.
The hydrostatic balance to which this number refers is of excellent appearance and condition. The manufacturer's mark REAL FABRICA, LXA. SCAPA PETRA is on the beam. The beam, that measures 42 cm, is maintained in equilibrium by a metal holder of 26 cm in height. The pans are circular and 18 cm in diameter.
The balance is currently mounted on the support of another balance that no longer exists (C.VI.105). It is probable that in the early Gabinete de Física in Coimbra, the experiments with the hydrostatic balance were carried out on the universal stand (instrument 24). Dalla Bella does not make reference to this, but 's Gravesande, to whom the Italian teacher repeatedly refers on this matter, used it as can be seen in the engraving in his book, Physices Elementa.
From Colégio dos Nobres, catalogue n.º 230.
Carvalho, Rómulo de, História do Gabinete de Física da Universidade de Coimbra, Universidade de Coimbra, Biblioteca Geral, Coimbra, 1978, p. 406.
's Gravesande, Willem Jacob, Physices Elementa, Leiden, 1742, Tab. XLIX, Fig.1 and 2.