Sextant, circa 1785

F6412-003

Sextant, circa 1785 Long Caption: Black-lacquered brass diamond-pattern frame, wooden handle. Signed on the base of the index arm 'Dollond London'. Bright brass arc from -4° to 136° by 20', measuring to 120°. Vernier to 30'', zero at right. Tangent screw and clamp screw on the back of the index arm. Magnifier on 80 mm swivelling arm. Three shades (red, red, green), three horizon shades (red, red, green). Index glass adjustment by screw, horizon glass by thumbscrew. Telescope bracket, perpendicular adjustment by rising piece and milled knob. Telescope (129 mm), inverted image, two cross wires. Shaded eyepiece (missing), adjusting pin. Radius 12'' (305 mm). In polished mahogany keystone box containing in the lid a trade label for Henry Hughes & Son, 59, Fenchurch Street, London. Credit line: © National Maritime Museum, Greenwich, London Object: NAV1113 Artist: Dollond Date: circa 1785 Medium: brass Size: 112 mm x 350 mm x 373 mm Click here to buy a bespoke print of this image.