F2106-1

Universal equinoctial ring dial Long Caption: Universal equinoctial ring dial for all latitudes. Standard dial (see related terms) except for the following details: On the latitude scale, which is divided clockwise from top 0°-90°-0°-90°-0°, 'S' and 'N' are marked either side of the top zero, and there is a scale for determining the solar altitude and zenith distance. On the obverse side and the inner-rim of the equinoctial ring is an hour scale, and the reverse is blank apart from the signature: 'Nat. Witham Fecit.' There is a date scale, a zodiac scale and a declination scale. The equinoxes are marked at 9 ½ March and 11 September and there is a wheatsheaf pattern along the outer edges of the bridge bars. Credit line: © National Maritime Museum, Greenwich, London Object: AST0365 Artist: Nathaniel Witham Date: circa 1715 Medium: brass Size: 5 mm x 188 mm Click here to buy a bespoke print of this image.