PENNINGTON for BARWISE, London. No 4387

88885

Fine and rare chronometer by this most important maker.

More details

Large silver case of true consular form (three piece hung on one joint), hallmarked London 1808, casemaker RG (Richard Grove, Clerkenwell)). Fullplate fusee movement of typical Pennington caliper with elongated sighting hole in top plate showing detent locking and impulse roller action with the escape, with cap jewels on balance (diamond) and escape. Pennington spring detent detached escapement with dovetail- footed detent and typically light escape wheel - see my drawing of the escapement. Pennington 'double-L' compensation balance with 5-turn blued-steel balance-spring. One-piece enamel dial signed for Barwise, gold hands. 55 mm diameter. 

John Barwise 'Chronometer, Watch & Clock Makers to their Royal Highnesses the Dukes of York, Kent, Cumberland & Gloucester' 29 St Martin's Lane, London, one of the most energetic clock and watch retailers of the period, and one of the first London firms to offer Pennington's superior spring-detent watches.


Robert Pennington, associated with Thomas Mudge junior in the manufacture of chronometers to his father's pattern, who later concentrated on the manufacture of spring-detent chronometers. Succeeded by his son Robert, the Pennington family were one of the leading London manufacturers of both pocket and box chronometers in the first half of the 19th century and devised, among other improvements, the screw adjusted balance that became the standard compensation balance used worldwide. 


NB: Despite what some authors and many auction houses continue to state, the 'L' portion of this balance (as with the earlier 'double T' balance) has nothing to do with middle temperature error and does not supply an auxiliary action. Rather, it was Pennington's method of protecting the free end of the bimetallic rim from distortion when the screws were either adjusted or moved - a tricky job with a screwdriver, especially at this early period when such balances were not well known.


Dial with faint hair cracks between 7 and 8, and the remains of a small crest, now worn, on the case back. Otherwise in good original condition. Cleaned and guaranteed.