D8659-1

Universal equinoctial ring dial Long Caption: Universal equinoctial ring dial for all latitudes. This dial has the means for measuring the altitude and zenith distance of the sun, and is combined with a circular slide rule. The main part of this instrument is an authentic 18th century dial with a circular slide rule included in the outer two rings. It appears that some of the scales may be later additions. The bridge, which is very poorly made, and the suspension ring are clearly 20th century replacements of lost originals. Credit line: National Maritime Museum, Greenwich, London Object: AST0184 Artist: unknown Date: 18th century Medium: brass Size: Overall: 5 x 106 mm Click here to buy a bespoke print of this image.