Beschreibung:

Robert Pennington No. 1/430 An exceptional Regency small size 55-hour Observatory chronometer of probable Royal provenance. Circa 1801 THE MOVEMENT Of fine execution, full plate construction, gilded 1. Train: with fusee, centre, third and fourth wheels with delicate hyperbolic crossings, motion wheels of brass, the arbors and pinions of polished steel, excepting the cannon pinion with 15-leaf brass pinion to the steel pipe with squared end, the balance and 'scape wheel jewelled with endstones to each and the fourth jewelled in pillar plate only. Count of 14,400 beating ½ seconds 2. Double mainspring assembly and fusee: fusee with Harrison's maintaining power and 11 turn cone. The sub-divided barrel assembly with double mainspring in two tiers with each spring (while attached to the common arbor) in its own barrel unit, the lower secured to the ratchet set up through the pillar plate, the upper fixed to the false barrel enclosing both units and carrying the fusee chain fixed at its outer end. Both springs dated K. Clark 1801 3. Escapement: Arnold-type spring detent, the gilt mounting block carrying separately planted steel detent proper and gold passing spring, each with facility for adjusting its depthing by means of an eccentric screw. Gold 'scape wheel of 16 teeth on the underside, umbrella wise. Compensated balance of Pennington's Y-C-C type, the three-armed solid brass rim with two bimetallic compensation affixes to its outside the timing adjustable by four quarter screws. Blued steel helical spring with adjustable collet at each end, having no terminal curves. 'Comma' shaped cock THE DIAL Of regulator format with annular minute ring, signed Pennington, London between the eccentric subsidiary rings calibrated for 24 hours above centred with crowned royal cypher GR and seconds below THE DRUM Of brass, containing the movement, glazed top and bottom, with vertical flange by '50' and attached hinged spring-loaded winding arm by '10' THE BOX Hexagonal, two tier, of Cuban mahogany with hinged brass observation cover signed Pennington London secured from the inside, and fixed brass plate on six cylindrical feet. Interior grooved for the drum flange, one exterior flat hollowed for the winding arm Box: 135 mm. greater width, 60 mm. high Movement: 88 mm. dial; 68 mm. pillar plate; 65 mm. top plate Plates: 1.3 mm. thick; 23 mm. top plate to dial; 16.6 mm. plate separation Drum: 95 mm. diam., 51 mm. high