Peto Cross Detent Chronometer by Brockbanks


Signed   Brockbanks     London
Circa   1800
Diameter   54 mm         

Out of stock


An early 19th Century English Peto cross detent chronometer in a purpose made gold consular case.  Full plate gilt keywind fusee movement with gilt dust cover.  Harrison’s maintaining power. Engraved cock with diamond endstone, polished steel regulator.  Unusual plain four arm gilt balance with four blue steel screws in the rim, blue steel spiral hairspring. Rare Peto cross detent chronometer escapement, the curved horn in gold, steel passing spring.  Escape pivots with endstones.  Purpose made white enamel dial with subsidiary seconds, Roman numerals, blue steel seconds hand with gold arbor, gold Breguet hands. Substantial purpose made 18 carat consular case with chased and engraved bezels and pendant.  Plain gold inner dome, maker’s mark “Y&D” and number corresponding to that on the movement.

The Peto cross detent is rare form of chronometer escapement.  It was seldom used despite the theoretical advantage of having the detent spring in tension as in an Arnold type detent but still retaining an escape wheel without friction.  Brockbanks appear to have appreciated the qualities of the escapement and used it more frequently than other makers.  The firm was formed by two brothers in 1781, John Brockbank, 1747 - 1806 and Miles Brockbank, 1754 - 1826.  By the late 1780's they concentrated on making chronometers becoming the largest supplier.  Thomas Earnshaw was employed by them.  See the December 2015 edition of the Antiquarian Horological Society for an article about Brockbanks.  This example has a case and dial made for it in USA.  

Interestingly a watch with the preceding number was part of the Ilbert collection, and is now in the British Museum.  The movement, also with a Peto cross detent, is almost identical and housed in gold pair cases hallmarked 1800.  It is illustrated in the Catalogue of Watches in the British Museum. Vol. VI.