695 GBP ($895 USD) + shipping

A very fine (as new) sextant by Gray and Keen of Liverpool, dated 1891


10 1/2 x 10 1/2 x 5 inches deep (26 x 26 x 13 cm.)




Gray and Keen

Country of manufacture

UK and Ireland

Categories: Surveying Instruments & Mining, Engineering antiques, Calculating, Navigational instruments


Extremely fine (as new) anodised/bright brass sextant with silvered scale running out to 150 degrees and engine divided to 1/10 degree and vernier with magnifier taking that to one arc second. Cased with all of it’s original eyepieces (sighting, low and high power and long tube with multi block cross hair grid. Separate sun shade (dark) filter also in case. 

This instrument is missing zero anodization/enamel or lacquer and has never been touched other than to refinish and re-line the mahogany case (with owner’s initials). The condition can only be described as new old stock. Certificate of accuracy dated to 1891. Ebony handle, all filters intact, mirrors are perfect as well. The silvered scale was oxidised black so I cleaned it just enough to highlight the scale divisions and the signature. The address is very rare as it indicates their (Gray and Keen) primary address of the Strand (all recorded instruments using 23-25 Strand) but also the nearby and parallel address of Canning Dock (see map of Liverpool c.1890, last photos).

This is an exceptional instrument for the connoisseur collector. There is not a scratch to be seen. If you wish additional photos in daylight, I can post more or individually to your email address. 

The sextant has a radius of 7 1/2 with an arc circle of 10 inches. The mahogany case (with all brass L- hooks and handle) measures 10 1/2 inches square by 5 inches deep (refinished).


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CA ScientificaOpticae

Scientifica Opticae

Mark Hacking (Scientifica Opticae Inc.) has been an avid collector/dealer for over 30 years. A former Science teacher, he has an innate love for anything natural or mechanical. Specializing in optical (microscopes, telescopes), surveying, medical, weighing and drawing instruments, he is an active participant of the Scientific Instrument Fair in London. Living in Stratford, Ontario, Canada, with his wife and two children; Mark looks forward to meeting as many fellow collectors as possible, and has a worldwide following on eBay (Sciopti).

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