Sextant

The sextant has an anodized brass diamond-pattern frame and a wooden handle. The tangent screw and clamping screw, both bent, are located at the bottom of the index arm. The instrument has four round grey shades and three grey horizon shades. The index and horizon glass and their mounts are missing. The magnifier is also missing.

Attached to the sextant is a threaded telescope bracket in two parts, fitted for correcting collimation error. It has perpendicular adjustment made by a rising-piece and a milled knob. The telescopes are missing. The sextant is in a poor condition.

The instrument has a polished brass inlaid silver scale of which the division survives, by 10 arcminutes, but the digits are missing. The sextant has a silver vernier measuring to 10 arcseconds, with zero at the right.

The instrument has no box.

The sextant was recovered from the wreck of a German warship scuttled at Scapa Flow at the end of World War I, and was given to Vice-Admiral Sir Henry Francis Oliver (1865-1965), in 1919 Commander-in-Chief of the Home Fleet.

Credit: National Maritime Museum, Greenwich, London