Eardley Norton marine chronometer no. 2322
Record status
Individual type · partial
Period
1785-1795
This marine chronometer by Eardley Norton dates to circa 1785–1795 and is housed in a brass drum set within an octagonal mahogany base. The white enamel regulator dial features central minutes with Arabic numerals, an upper subsidiary seconds dial, and a lower subsidiary hour dial with Roman numerals.
The dial is signed 'E NORTON LONDON', and the back plate is numbered '2322'. The twenty-four-hour movement includes an Earnshaw-type spring detent escapement, a reversed fusee with maintaining power, and a two-armed bimetallic balance.
Evidence at a glance
- Linked sources
- 1
- Photograph views
- 1
- Catalogue references
- 0
Counts describe this entry’s documentation, not authenticity, rarity or completeness. Photographs may show one specimen; check each caption and licence.
Technical characteristics
- Type
- Box marine chronometer
- Escapement
- Earnshaw spring detent
- Case material
- Mahogany
- Museum number
- 1958,1006.1940
- Dial signature
- E NORTON LONDON
- Place recorded
- United Kingdom
- Production place
- London (St John Street)
- Back plate number
- 2322
- Maker / attribution
- Eardley Norton
Design
- Visible features
- • Circular white enamel regulator dial showing central minute hand and outer track with Arabic numerals at five-minute intervals. • Upper subsidiary seconds dial and lower subsidiary hour dial marked with Roman numerals. • Signed 'E NORTON' to the left and 'LONDON' to the right of the central hand arbor. • Winding aperture located to the right below the 'LONDON' signature. • Movement and dial mounted within a dark polygonal (octagonal) surround.
- Dial and Indication
- The timepiece features a slightly domed enamel regulator dial signed 'E NORTON LONDON' and secured to the dial plate by two small screws on the edge. It contains an outer minute track and two subsidiary dials for seconds and hours. The hour hand is not original. It is noted that there is no sign of scribed divisions under the enamel of the minute and seconds markings.
- Movement and Mechanism
- The movement features a full plate construction with four baluster pillars. It employs a reversed fusee with stop-work and maintaining power. The barrel is of large diameter, made from a bent and soldered strip. The escapement is of the Earnshaw spring detent type and is described as having massive proportions. The bimetallic two-armed balance is similar to the Arnold 'z' type and includes steel timing screws.
- Evidence of Modification
- The dial plate is of larger diameter than the front plate and retains holes from a former case catch and hinge. The movement frame contains various unused holes, including a threaded pillar and a pair of holes near the fourth wheel, possibly for a balance stop or train device. Adjustments to the detent mechanism were modified as an adjusting screw has broken off, and the arm is currently fixed with two screws.
- Case and External Construction
- The movement is contained within a brass drum which is rigidly fixed inside an octagonal mahogany base measuring 148 mm across the flats. A brass bezel with bevel-edged glass overlaps the base and is secured bayonet fashion. Though the drum is now immovable, tapped holes in the base sides may have served as pivot points for a gimbal ring. The base also features two brass securing screws, and the dial plate is fitted with a positioning peg.
Identification
- Serial number
- 2322
- Source note
- Facts transcribed from the linked source listing or collection record. Attribution and specifications are source-reported and have not been independently authenticated.
Catalogue references
No catalogue numbers recorded. Numbers are only published once transcribed from a verified edition of a standard catalogue — they are never inferred.
Research required
- Research required: Source notes the hour hand is not original.
- Research required: The internal movement, back plate, and lower case structure are not visible in the provided top-down photograph.