George III Cased Double Framed Sextant by Robert Brettell Bate of Poultry, London

For sale, a rare mahogany cased early nineteenth century double framed sextant by Robert Brettell Bate of Poultry, London.

The double frame is the most prized of all sextants amongst collectors and was devised by the equally famous Edward Troughton in 1788. This example is comprised of two frames connected by numerous pillars with index arm containing a Vernier and clamp release with adjustable magnifier over the top. The silvered arc is divided from 0 – 140 degrees and is signed to ‘Bate, Poultry, London’ to the base. It has four index shades and three horizon shades and a telescope (not original). The back has an original ebony handle and telescope adjustment screw.

The sextant comes complete with its original case and has a brass fouled anchor bearing the initials ‘AR’ to the top.

There is a crack in both the index mirror and the horizon glass which could be replaced upon request but I have chosen to leave then both in place for reasons of originality. This and the lack of original telescope are both reflected in the price.

Given all of the above, this is a superbly crafted and rare sextant from an early period. Examples of this quality by good makers are scarce and I have found no other example from this maker in the course of my research.

Robert Brettell Bate was a very high quality manufacturer of scientific instruments working in the early part of the Nineteenth Century. Born in 1782, he took over the business from his Uncle in 1804 who had already received a commission from the Government’s revenue department to produce hydrometers. This relationship continued under Bate’s stewardship and appears on his trade cards of the period and in 1824 was further commissioned by the Board of Excise & Ordnance to make the new national standard measures for weight & capacity.

His quality of manufacture led him to receive Royal Appointments from George IV, William IV and Queen Victoria where he acted as Optician and he further served as the Master of the Spectacle Maker’s Guild in 1833. He was also known to have acted for the Admiralty as its main chart agent with numerous sub agents acting below him such as the instrument maker to The Royal yacht Club, George Stebbing. Bate traded from numerous addresses in Poultry street, London from 1808 to 1846 whereafter he moved to number 33 Royal Exchange in 1846 until his death in 1847.

Circa 1810