Surveyor's pocket box sextant made by William and Samuel Jones, Holborn, London, England, 1850-1859. Consists of two circular lacquered brass plates with lid that acts as a handle when used. Fitted with Inlaid silver 131° scale (-5° to 150°) with 30' divisions and a silver vernier (1' div.). The index arm is rotated by a milled knob on the upper plate with two filter shades (red & green) operated by lever. The index glass is fixed with adjustment for the horizon glass. Fitted with magnifier (single lens) on hinged 38 mm swivel arm and choice of a large and a small pinhole sight but telescope missing.