AUGUSTE-LOUIS BERTHOUD, NO. 310, CIRCA 1875
Details
A NAPOLEON III MAHOGANY TWO-DAY MARINE CHRONOMETER
Auguste-Louis Berthoud, No. 310, circa 1875
The frosted silver dial of regulator format signed Ate Berthoud No. 310, hours dial with Roman numerals, (at XII), outer minute dial with Arabic five minute intermarkers 5-10-15 et seque, subsidiary seconds dial (at VI), up-and-down dial (at III), blued steel hands, 14,400 train, Earnshaw escapement, cut three-armed bimetallic balance, with segmental heat compensation weights, the impulse jewel with protection strip over jewelled impulse pallet, blued steel helical balance spring, balance bridge surmounted by top balance pivot jewel cock, turned tapered steel pillars with square head nuts, in locking brass drum the whole contained in outer gimballed brass bowl with bolt action locking arm, in plain two-tier mahogany box, the top with non-glazed viewing port, the sliding cover inset with brass diamond shape plaque and thumbpiece, bone ivory disc to front inscribed A. BERTHOUD No. 310, brass external drop handles
77 mm. dial diam., 166 mm. sq. base or box
Auguste-Louis Berthoud, No. 310, circa 1875
The frosted silver dial of regulator format signed Ate Berthoud No. 310, hours dial with Roman numerals, (at XII), outer minute dial with Arabic five minute intermarkers 5-10-15 et seque, subsidiary seconds dial (at VI), up-and-down dial (at III), blued steel hands, 14,400 train, Earnshaw escapement, cut three-armed bimetallic balance, with segmental heat compensation weights, the impulse jewel with protection strip over jewelled impulse pallet, blued steel helical balance spring, balance bridge surmounted by top balance pivot jewel cock, turned tapered steel pillars with square head nuts, in locking brass drum the whole contained in outer gimballed brass bowl with bolt action locking arm, in plain two-tier mahogany box, the top with non-glazed viewing port, the sliding cover inset with brass diamond shape plaque and thumbpiece, bone ivory disc to front inscribed A. BERTHOUD No. 310, brass external drop handles
77 mm. dial diam., 166 mm. sq. base or box