Astronomical quadrant Product:Fine art poster Front view of buildings on

Front view of buildings on Aldersgate Street

It shows the conservatory with a large dome which contained wild animals

View of Powis House

Kilburn Park

with figures and boats on the River Thames

Astronomical quadrant Product:Fine art poster Front view of buildings onA 12 inch astronomical quadrant made by John Bird. Astronomical quadrants were used to measure the angle of a celestial object from the zenith. Operated in conjunction with a transit instrument, they could be used to check the running rate of astronomical clocks known as regulators. At sea a quadrant can be used to help fix a ship's position and to determine latitude. ca. 1767