A 5IN. VERNIER SEXTANT BY TROUGHTON & SIMMS, LONDON, CIRCA 1820
the polished brass frame with arc signed as per title and inscribed silvered scale divided to 150º, vernier with clamp and magnifier, index arm engraved CLYDE ENGINEERS' OFFICE No. 2, threaded wooden handle contained in fitted keystone box complete with sighting tubes and filters
Extraordinary, mid-1800s presentation sextant made by one of England’s most elite makers! This delightful little instrument is signed on the large arc in perfect hand-engraved script, “Troughton & Simms, London.” Of all brass construction with a V-shaped frame, the sextant has an inlaid silver arc reading from -5 to 150 degrees. Incredibly, these divisions along with the vernier scale on the index arm, allow this sextant to match the accuracy of it larger cousins, down to 20 arc seconds! A pivoting magnifier is provided for taking the reading. The index arm has a miniaturized version of a thumb screw stop and tangential fine adjust. The sextant is complete with its 3 horizon filters and 4 index filters in perfect condition. The index mirror and horizon mirror are in beautiful condition. The whole presentation is totally complete in its shaped rich mahogany box. The ebony handle screws into the frame with a secure fit. There are three optics, a peep and a telescope which fit into the height-adjustable sight holder. Rounding out the accessories, there are both sight tube filters. Of monumental importance for its value and appeal is the beautifully- -engraved presentation on the index: Clyde engineer’s office Nr. 2.