細節
An eight-day marine chronometer
Porthouse & French, No. 7276, circa 1865
The silvered dial signed and numbered Porthouse & French, MAKERS TO THE ADMIRALTY, 16 Northampton Sqre. LONDON. 7276, Roman hour numerals, gold hour and minute hands, subsidiary seconds and up-and-down dials with blued steel hands, main frame assembly carrying fusee, barrel and centre wheel, sub-frame assembly with chain guard and carrying remainder of the train and Earnshaw escapement, cut bimetallic balance, blued steel helical balance spring, spring foot detent with jewelled locking stone, brass bowl and gimbal, three-tier brass bound rosewood box, the middle section with inset ivory rectangular plaque inscribed PORTHOUSE & FRENCH. MAKERS TO THE ADMIRALTY 16 Northampton Square. LONDON, the bottom section with inset bone disc inscribed WM. WEICHERT 112 BUTE DOCKS, recessed brass handles
115 mm. dial diam., 215 mm. sq. box
