Guiding the greats: Vancouver’s lost sextant from Cook’s voyages of discovery re-emerges

Captain George Vancouver, himself one of the great 18th century explorers, accompanied Captain James Cook on his second and third voyage of discoveries as a young midshipman. With him he took this sextant, made in London c.1772 by Jesse Ramsden (1735-1800), one of the leading British instrument manufacturers of the day, responsible for supplying instruments for some of the most famous expeditions of the era.
 
Discovered among the effects of a retired naval officer in Portsmouth c.2005, its significance only became apparent after cleaning revealed the inscription to G Vancouver.
 
In an extraordinary twist of fate, Vancouver was not entirely satisfied with the sextant and wrote a letter of complaint to its famous maker. This caused Ramsden to respond with a robust defence of it to the Board of Longitude, claiming the error was no more than a 1⁄4 of a minute of arc, having re-tested it on Vancouver’s return. From this we know that it was carried on the two voyages of discovery.
 
Now, on the 250th anniversary of Cook’s First Voyage of Discovery, rare books and maps dealer Daniel Crouch will offer the sextant at the London Map Fair at the Royal Geographical Society in Kensington Gore, London SW7 on June 9 and 10.
www.londonmapfairs.com