Equatorial telescope. A brass telescope mounted on a set of large, ornate brass wheels with finely graduated scales on them.

ABDNP:200001a

Universal equatorial instrument. 18th century instrument for positional measurement of stars with telescope mounted on an equatorial mount having finely graduated scales. Brass with 18" circles. Originally made by Sisson. Afterwards divided anew, with an achromatic telescope and 'refraction apparatus' (to correct for atmospheric refraction) added by Ramsden. Optics missing. Badly cleaned sometime 1955-1965.

created 1760-1777, modified by Ramsden in 1782

Brass, glass. The large rings are 457.2 mm wide.

Jeremiah Sisson (1720-1783), modified by Jesse Ramsden (1735-1800)

Patrick Copland, astronomy, telescope, science, history of science

Physical Object

30797b5d-891f-43ca-aeaf-472524fb3011