Details
A FRENCH SILVER-CASED POCKET CHRONOMETER
Ferdinand Berthoud, No. 4/A, dated 1799
The gilt centre area of the dial signed Const Par Ferdinand Berthoud. Execte Par Jean Martin 1799, applied eccentric silvered hour and minute chapter ring (at XII) with concentric hour and minute numerals, its gilt centre engraved No. 4/A, blue steel hands, outer annualar silvered Arabic seconds ring with counter-weighted blued steel sweep hand, full plate 14,400 count movement, cut three-armed bimetallic balance each sector with circular underslung heat compensation weights and mean time screws, balance 'stop/start' assembly operated by slide situated beside the minute chapter (at 15), flat blued steel balance spring, the outer coil pinned to pierced centre rectangular steel stud mounted on small brass cock, Earnshaw escapement, pivoted detent with steel locking pallet, silver case with marks for PARIS DEP SEINE 1798-1809, casemaker Antoine-Henry Krabbe 1798-1811
Ferdinand Berthoud, No. 4/A, dated 1799
The gilt centre area of the dial signed Const Par Ferdinand Berthoud. Execte Par Jean Martin 1799, applied eccentric silvered hour and minute chapter ring (at XII) with concentric hour and minute numerals, its gilt centre engraved No. 4/A, blue steel hands, outer annualar silvered Arabic seconds ring with counter-weighted blued steel sweep hand, full plate 14,400 count movement, cut three-armed bimetallic balance each sector with circular underslung heat compensation weights and mean time screws, balance 'stop/start' assembly operated by slide situated beside the minute chapter (at 15), flat blued steel balance spring, the outer coil pinned to pierced centre rectangular steel stud mounted on small brass cock, Earnshaw escapement, pivoted detent with steel locking pallet, silver case with marks for PARIS DEP SEINE 1798-1809, casemaker Antoine-Henry Krabbe 1798-1811