Astronomical quadrant Product:Fine art poster held for him at the

held for him at the end of May 1858

Interior view of the dining room at Charterhouse

Behind can be seen Lord Derby's crown and

by Sydney Parkinson (London

Front view of buildings on Aldersgate Street

Astronomical quadrant Product:Fine art poster held for him at theA 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