Universal equinoctial ring dial

Universal ring dial 17th century. Brass inscribed 'THO.TOMPION IN FLEET STREET FECIT'. These dials can be used in any latitude (except the polar regions) for telling the time and calculating the altitude of the sun. Thomas Tompion (1639-1713) was renowned for his horological expertise, but also made scientific instruments for members of the Royal Society.

This instrument was probably retailed; possibly even re-signed by Tompion, but is NOT a product of his workshop. Other possible makers are Edmund Culpepper or J Marks. Edmund Culpeper, the son of a Dorset clergyman, was apprenticed to Walter Hayes in 1684 and gained his freedom of the Grocers Company in 1714. Before this, however, he had begun trading at Hayes' workshop - the Cross Daggers in Moorfields. Culpepper had a shop near the Royal Exchange in Cornhill later in his career. He is known to have sold barometers, quadrants, compasses, sectors and sundials. He also advertised a burning glass, Hadley's quadrant, prisms, rules, spectacles and telescopes. A form of simple microscope was named after him. He died in 1737, and his son followed him in the trade.