Accession No
1178
Brief Description
universal equinoctial ring dial, by Henry Sutton, English, 1660
Origin
England; London
Maker
Sutton, Henry
Class
dials
Earliest Date
1660
Latest Date
1660
Inscription Date
1660
Material
metal (brass)
Dimensions
length 144mm; diameter 115mm (length 117mm; diameter 105mm; 17-1-2000)
Special Collection
Provenance
Transferred from the Museum of Archaeology and Ethnography, University of Cambridge (now Museum of Archaeology and Anthropology). From the collection of Baron Anatole von Hügel.
Inscription
‘Hen: Sutton fecit 1660’’ (meridian ring)
‘Willm . Rook’ (reverse of equinoctial ring)
Description Notes
Meridian ring calibrated for northern latitudes, divided 0 - 90˚, numbered by 10˚, subdivided to 1˚. Suspension shackle (suspension ring missing). Equinoctial ring divided I - XII, I - XII, numbered by I, subdivided to 15 minutes; altitude quadrant divided 0 - 90˚, numbered by 10˚, subdivided to 30´. Pierced bridge with date scale divided to named (initialled) month, subdivided to 5 days; on reverse a declination scale divided 23˚ 30´ - 0 - 23˚ 30´ (and 20-0, 0-20), numbered by 1˚ (1st Aries = 10 March). (Sliding pinhole gnomon; 17-1-2000).
Condition: fair.
References
Events
Description
The universal equinoctial ring dial was designed by the English mathematician William Oughtred in the first half of the seventeenth century. It could be used at any latitude, so was a popular timekeeper for sailors and other travellers. It was really a much simplified version of the armillary sphere, only keeping the parts which were needed for telling the time.
The universal equinoctial ring dial consists of two rings and a bridging bar inside the inner ring. The outer ring represents a circle passing through the North and South celestial poles. The inner ring is called the ‘equinoctial’ ring because it represents the celestial equator. The bridging bar represents the axis of the world, just as the gnomon on an ordinary horizontal dial does. So the instrument is a very simple model of the heavens.
01/02/2001
Created by: Dr Hester Higton on 01/02/2001
FM:40004
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