Brass sextant with pendulum artificial horizon.

Made:
1835-1845 in Strand
maker:
Alexander Bridport Becher
and
William Cary

Brass sextant with lacquered frame and limb, wooden handle and fitted with artificial horizon invented by Alexander Bridport Becher in 1834, and made by William Cary, London, England, 1835-45. Consists of inlaid polished silver 126° scale (-5° to 150°) with 20’ divisions and silver vernier (20”), three index-filter shades (red & 2 green), three horizon filters (red & green), scale magnifier on 55mm swivelling arm. Fitted with threaded telescope bracket for sighting telescopes (151mm – inverted image). The horizon consists of a 93-mm-long anodized brass tube with a bracket for attaching it to the sextant. The tube contains a pendulum that is lowered into a conical attachment (missing) filled with almond oil to dampen the pendulum's movement. A separate oil lamp (missing) can be fixed to the bracket for illumination at night.

Details

Category:
Navigation
Object Number:
1910-233
type:
sextant and artificial horizon
credit:
Adams, E.T.