Overall: 1 1/2 x 8 1/8 x 6 1/8 in. ( 3.8 x 20.6 x 15.6 cm )
Brass astrolabe; disk with three circular holes in upper half, numbered scale divided into quandrants incised around edge, and rotating bar across center with pierced right-angled tabs at either end; ring swivel-mounted at top.
Gift of the Half Moon Committee of the Hudson-Fulton Exhibition, 1909
Due to ongoing research, information about this object is subject to change.