Equatorial Quadrant & Astronomical Ring. London and Spain, c. 1800

Equatorial Quadrant & Astronomical Ring. London and Spain, c. 1800.
Gilt and engraved bronze.
Signed: Robert Tangate & Philip ?
They show wear and tear.
Measurements: 15 x 15,5 x 15,5 cm and 23,5 x 22 x 22 cm.

The first of the pieces, made by Robert Tangate, around 1790, is an equatorial quadrant, an astronomical instrument used between the 17th and 19th centuries to measure the height of the stars above the horizon and to determine the local time by means of solar or stellar observations. Its design evolved from older instruments, such as the astrolabe or the wall quadrant. Tangate was a member of the Guild of Carpenters, working in various premises in the Fleet Street area of London from 1766 to 1808.

The second of the pieces, also signed, is an astronomical ring, a portable instrument historically used to measure the height of the Sun and determine solar time, geographical latitude or even the date. It was especially popular in Europe between the sixteenth and eighteenth centuries, serving as a "portable sundial". When correctly oriented according to latitude and date, a ray of sunlight passes through a small hole (gnomon) projecting a luminous point on the time scale. Its accuracy and portability made it an essential tool in the age of exploration.