Accession No


Brief Description

grand orrery (planetarium), by George Adams Snr., English, c. 1750


England; London; Fleet street


Adams, George (Snr.)


astronomy; demonstration

Earliest Date

Jan. 1, 1741

Latest Date

Dec. 31, 1752

Inscription Date


glass; metal (brass); wood (ebonised oak?, mahogany); ivory


1050mm (orrery diameter), 1240mm (dome diameter), 1020mm (dome height), 680mm (table height)

Special Collection


Transferred from the Sedgwick Museum of Earth Sciences. Transferred to the Sedgwick Museum of Earth Sciences from St. John's college in 1904 by by Rev. Peter Mason, President of the College. Bequeathed to St John’s in 1904 by former fellow, Master and Fellows of St Johns.


‘Made by
HEAD in Fleet Street
LONDON’ (on clock face)
TROPIC OF CANCER (on circles)
Mercury D
Venus D
1 322
11 314
29 168 (on each metal disc)

Description Notes

Grand Orrery (planetarium), by George Adams, English, c. 1750.

12 sided wooden (? ebonised oak) base with 12 brass ball feet. Central rectangle on each side panel raised with hand painted and gilded illustrations of the signs of the zodiac. One panel with 2 brass knurled knobs (? function) and key hole for brass crank with oak handle.
6 metal discs of increasing diameter for the planets - Mercury, Venus, Earth, Mars, Jupiter, and Saturn. Painted black with gold band marking path of planet. Mercury, Mars, Jupiter and 4 satellites, Saturn,ring and 5 satellites all in brass. Venus in ivory with one half painted black illustrating phases. Central brass disc engraved with sun image below brass sun. Earth and moon on 2 smaller metal discs (black with gold line). Moon mounted on inner circle a metal sphere half painted black to illustrate the phases of the Moon. Ivory earth mounted on central brass disc graduated 0 - 30˚ for each zodiacal sign, subdivided to 1˚, and with symbols of the zodiac. Ivory earth marked with outline world map, equinoctial and solstitial colures. Arctic & Antarctic circle, Tropic of Cancer and Capricorn, Equator & Ecliptic and 20 lines of longitude. On tilted axis with clockwork mechanism operating the motion. Opposite Earth - brass clock engraved with hours to 1/4 hour on outer dial and minutes on inner. 2 pierced iron hands. Brass ecliptic circle round diameter mounted on 12 brass pillars, divided 0 - 30˚ for each zodiacal sign, numbered by 10˚, subdivided to 30´ with symbols and abbreviated names of the zodiac. All engraved and filled with black paint. Calendar, starts on March 9th, outside zodiac, numbered by 10, subdivided to 1 day with full name of each month. Supports hemisphere. Equinoctial colure, graduated 30˚ - 90˚ - 0 - 20˚, numbered by 10°, subdivided to 1°, and solstitial colure; ‘ARTICK CIRCLE’; ‘TROPICK of CANCER’; half equator divided 180 - 360°, numbered by 10°, subdivided to 1° and 0 - 60˚, numbered by 20˚, subdivided to 4°, and VI - XII, I - VI, numbered by I.
Under 12 sided glass dome with shackle; mounted on mahogany base in turn mounted over 12 glazed panels, corresponding with panels illustrating zodiac. In mahogany frame on bow legged mahogany table with castors. (Later addition)



Liba Taub; 'The 'grand' orrery'; Explore Whipple Collections online article; Whipple Museum of the History of Science; University of Cambridge; 2006:


An orrery is a mechanical model of the Sun, Earth, Moon and planets, intended to illustrate the mechanism of our solar system. Complex gearing, hidden inside the instrument, revolves these bodies at exact relative speeds when a handle is turned, demonstrating planetary motion according to the laws of Newtonian gravitation, as well as concepts such as day and night, the seasons, lunar phases, and eclipses. Built by the renowned instrument-maker George Adams (who supplied instruments to King George III), this ‘Grand Orrery’ includes the 6 then-known planets and their satellites, rotating around the sun at centre. Uranus, Neptune and Pluto are not present, as they had not yet been discovered.

Astronomy was considered an appropriate pursuit for ‘polite society’ during the 18th century. It was thought to encourage rational thinking, as well as inspiring contemplation of the divinely-created universe. Large enough that family and friends could view this orrery as a group, its wealthy owner may have used the instrument for education and entertainment during social gatherings. As this orrery was calibrated for the Julian calendar (abandoned in favour of the Gregorian calendar system in 1752), we can assume it was created before this date.
Created by: Joshua Nall on 18/12/2013


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