Orrery Collection ball and socket joint
This ball and socket joint (formerly separately inventoried as Inv 94029) most probably belongs with the plane table by John Worgan - Inv. 18184. The original listing of the Orrery collection includes "A small Plane Table, Ball & Socket, & a brass Index and Sights" (R.T. Gunther, Early Science in Oxford, vol. I (Oxford, 1923), 380).
In the Museum's Collections files there is a photograph which shows the joint juxtaposed with the plane table and the Orrery Collection graphometer (inv. 17420). (The print is marked up for publication and appeared in modified form - with the joint removed and alidade inv. 18184 pasted over - facing p. 374 of Gunther.)
Gunther also illustrates at p. 369 the Worgan circumferentor (inv. 15472) on a tripod, with the same or a similar ball or socket joint as the connection. The tripod (also inv. 15472) should be checked to see if its ball and socket joint is integral.
Other narratives:
- Surveying instruments: plane table and graphometer
- Orrery Collection plane table and alidade
- Inventory no. 18184 - Former Display Label
- Former Display Label - The Orrery Collection of Scientific Instruments
- Former Display Label - The Principal Makers of Instruments in the Orrery Collection
- Orrery Collection: 1731 Inventory
- Orrery Collection in print
- Accession Record : Extract from Annual Report for 1925