A fine and very rare English 19th century highly engraved chain driven fusee chronometer lever pocket watch , made by the famous chronometer firm of Thomas J. Mercer of London. The watch movement just fully cleaned and overhauled by my watch-maker, and with a sweet crisp action and keeping good action. This watch is guaranteed to be a rare chronometer lever as shown in the pictures below and movement, dial and case are original to each other and guaranteed as such. The watch with several features which brings it into the rare and possibly unique category: the fine and rare English form of the Robin Escapement; the movement highly jewelled through the train with "Liverpool Windows" held in gold chatons and screwed into place; a true bimetallic balance with gold timing screws, of a design patented by Mercer; finally the case and movement are in pristine condition, with tight solid 9k gold hinges and excellent gilding; typically for watches from this period, the dial with several hairlines. The watch with a very rare movement, which is the English form of the Robin Escapement, ca. 1860's. The full plate of 16 size and in excellent condition. This is a very rare item, see www.antiquewatchstore.co.uk, site index for a movement only.
Further information may bae found in the Patent No 2432 of October 1856, by George Morton of Yorkshire. Also the Time Catalogue Museum Catalogue of Chronometers, has a reference and this is item No 104. This escapement is a combination of the lever as to the locking and the chronometer as to the impulse. It involves a little drop and therefore waste of force as a tooth of the wheel just escapes at the "passing" beat where no impulse is given. But it should be understood that a single-beat escapement involves no more loss of force and the escape of no more teeth than a double one, except the slight drop in the duplex and this lever chronometer or others on the same principle. The watch also has a rare patented balance, see http://www.knirim.de/chapman.htm for further details and a useful account of Mercer military time-pieces and chronometers; also see the book on the Mercer Family.
THE DIAL: 95% mint, the raised ivory enamel dial with fine black Gothic numerals, and a separate minute track to outside of dial and small minute markers. The bright white enamel dial in crisp condition, with no hairlines, but a small centre chip and a small chip to edge of seconds ring. The dial diameter of 44 mm, and with original gold spade hands and seconds hand. The dial with small seconds subsidary dial and large bold outer chapter ring. The glass is in fine condition..
THE MOVEMENT: 100% mint, with richly gilded full plate in wonderful condition. The well engraved balance cock and foot in superb condition with foliage and a diamond end-stone. The back plate with further decoration and Bosely time regulator, most unusually inset into the balance cock. A cut two arm bimetallic balance with gold timing screws. The movement with a chronometer-lever escapement, with brass escape wheel, with flat hairspring and fusee and chain. The movement further jeweled with nicely inset large jewels to the pallets and escape wheel and 3rd wheel and through the train, including upper plate jewel for fusee arbor. The watch signed, Manufacturer, T. J. Mercer, 9433. The watch movement in good order. The movement size with original finely gilded dust cover has a diameter of 42 mm. The movement with round ballustar pillars. Polished steel movement bolt with its original blued steel screw. Pierced gilded fusee stop work with iron hinge.
THE CASE: 100%, the original solid silver case measures an impressive 51 mm outside diameter. The 9k gold hinges are excellent with the case covers all closing tightly, and the bow is original to the case. The watch case with London hall marks and sterling stamps and number 9433. This is a very good quality and a substantial case, in fine order for a 140 year old chronometer lever watch and rare indeed. The case with the silver sponsor mark of "RO" for the famous case making family of Oliver, this example being for Richard Oliver of 19, Galway Street, St. Lukes, Clerkenwell, London. (See NAWCC Bulletin, 1994, Supplement 20, Spring, Chapter 6 for aricle on watch case makers of London). If required a copy of the article will be included with the watch. The bow and pendant also in good order. The watch has clearly been highly valued and well looked after. The case with a worn decoration to case band and crisp and clean top and back covers, most unusual to find. The watch case has not been buffed up or over-polished as seems to be the case so often with early watches.