The oldest Gregorian telescope
This is probably the oldest surviving example of the reflecting telescope invented in 1661 by James Gregory, which became the most popular type in the 18th century.
In the Gregorian telescope light is received and reflected by a concave mirror, and then by a smaller concave mirror through a hole in the larger mirror and into the eyepiece.
- Inventory no. 20020 - Internal Exhibition Label Text 'English Telescopes'
- Inventory no. 20020 - 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 in print
- Orrery Collection: 1731 Inventory
- Accession Record : Extract from Annual Report for 1925