signed Edm Culpeper Londini, the meridian ring engraved with latitude scale 90-0-90 degrees, reverse with scale for determining solar altitude and zenith distance, equinoctial ring with obverse engraved with hour scale in Roman numerals, central bridge with pin-hole sliding over a calendar scale (missing suspension ring), 15.0 cm diameter

Edmund Culpeper (1670-1737) was apprenticed into the Grocer's Company to Walter Hayes, engraver and mathematical instrument maker of Moorfields London in 1684. By 1700, Culpeper had taken over his master's shop and continued to trade under the sign of the crossed daggers, in Moorfields. Culpeper is perhaps best known for his contribution to optical instruments, in particular microscopes. However, he was also highly acknowledged for producing mathematical instruments, with particular skills in the engraving of scales, dials, and sectors.