Brass pillar-frame sextant.

Brass sextant, straight pillar frame pattern (20 bars), with wooden handle and threaded hole for attachment to stand in fitted mahogany keystone box, by John and Edward Troughton, London, England, 1795-1804. Consists of inlaid silver 132° scale (-5° to 150°) with 10’ divisions and silver vernier measuring to 10”, four filter shades (two red, two green), three horizon shades (two red, one green) and scale magnifier 60 mm swivelling arm. Fitted with threaded telescope bracket for telescope (182 mm) inverted image, two parallel cross-wires and extra draw tube (80 mm), inverted image with two parallel cross-wires. The case carries the trade label of William Heath, Devonport, stuck over an older, illegible labels.