A fine late 19th century brass double frame quintant with graduated silver arc and gold vernier, brass frame and fittings with traces of black on various parts of the sextant surfaces. Engraved on arc "Henry Hughes & Son, 59 Fenchurch St. London". Above is the serial number 3539.
An exceptional maritime instrument surviving in good working order and complete with four scopes, filters and adjustment wrench. The silver scale is calibrated -5 to +155 degrees and the silver vernier scale reads from 0 to 10 arc seconds in 2 second intervals. The sextant has four shades for the index mirror, and three shades for the horizon mirror, all surviving in good order. The sextant, scopes and accessories are housed in its original mahogany box with brass carrying handle on one side. The box lock and keep are still intact, but the key is missing.
Rosewood handle, index arm clamp, and swing arm magnifier are complete and in good working order. The telescope adjusts up and down by turning a knob located below the frame.
The original inspection certificate is attached to the felt-lined box top interior. The label states: THE NEW OBSERVATORY, RICHMOND, SURREY, CERTIFICATE OF EXAMINATION. CLASS A. THE SEXTANT 3539 OF 8 INCHES RADIUS BY (written in pen) H. HUGHES & SON, LONDON DIVIDED ON SILVER AND READING TO 10 HAS BEEN EXAMINED AT THE KEW OBSERVATORY. THE SHADES AND MIRRORS ARE FOUND GOOD. THE TELESCOPES ARE ALSO SATISFACTORY AND THE POWERS ARE FOR THE INVERTING 12 and 6 LINEAR AND THE ERECT 3 LINEAR. THE FOLLOWING ARE THE MEAN CORRECTION TO THE ARC (IN ADDITION TO THE INDEX CORRECTION) :- written in pen on the certificate. Dated April 1895 by Charles Chree (superintendent of the observatory. Also written in pen, upper left corner Index Error (not legible) and upper right (SUBL. 15, 30 August 1895).
A second inspection certificate is attached over the original inside the box lid was issued by Mersy Docks & Harbor Board, Liverpool Observatory, Bidston, Birkenhead, and dated Feb. 15, 1916. This certificate of examination also states "The sextant no 3539 of 8 inches radius by H. Hughes & Sons, London divided on silver and reading to 10 has been examined at the Liverpool Observatory. The telescopes, shades, mirrors and arc are found good and the instrument is approved for the determination of Lunar distances, latitudes, local times and azimuths, with a maximum error of 1' 50" of arc. (With correction chart and signed W.R. Plumner, Director).
Screwed to the back top edge of the box interior is a rectangular ivory plate stating "HUGHES & SONS, OPTICIANS, 59 FENCHURCH ST. LONDON.
A label is also attached on the back board of the box interior "KELVIN WHITE & HUTTON, CHRONOMETERS AND NAUTICAL INSTRUMENT MAKERS, ADMIRALTY CHART AGENTS, COMPASS ADJUSTERS. LORD KELVIN'S (SIR WILLIAM THOMSON) COMPASSES, SOUNDING MACHINES, ETC. II BILLITER STREET, LONDON, E.C. GLASGOW ADDRESS, 16.18 & 20 CAMBRIDGE STREET.
A brass plate fitted on to the top of the box lid is inscribed "T QUAIT, 1895.