Zenith Bezel-Wound Marine Chronometer

Technical characteristics

Date

Mid-20th century

Type

Two-day marine chronometer

Escapement

Club-foot Swiss lever

Case Material

Mahogany with brass

Power Reserve

Two-day duration

Place recorded

Switzerland

Winding Mechanism

Bezel-wound

Maker / attribution

Zenith

Design

Visible features

• Silvered-brass dial with dual 12/24 hour indicators. • Movement plate features spotted gilt decoration. • Mahogany case with brass hardware and gimbal suspension. • Serial number 25036 visible on the movement plate.

Movement and Escapement

The movement is a three-quarter plate configuration finished with spotted gilding. It incorporates a keyless design utilizing a large moving barrel. A distinguishing feature is the bezel-winding mechanism, which enables the chronometer to be wound by turning the brass bezel, while lifting and rotating it allows for time setting. The oscillation system is mounted on a sub-platform and comprises a compensation balance paired with a blued-steel overcoil hairspring. The escapement is a club-foot Swiss lever, with jeweled end-stones fitted to both the lever and escape wheel pivots, controlled by a polished steel regulator.

Dial and Navigation Features

The dial is constructed from silvered brass and features clearly legible Arabic numerals. It indicates the primary hours 1 through 12 in a large format, with a secondary track for 13 through 24 hours. The dial also includes a sub-seconds register and a power reserve indicator marked 'Haut' and 'Bas'. Blue-steel hands are used for time indication. The movement is mounted within a brass gimbal system designed to maintain equilibrium at sea, which includes a mechanical lock. The entire assembly is housed in a two-tier mahogany box featuring brass corner reinforcements and a shallow upper lid.

Construction and Technical Details

The instrument employs a unique arrangement where a central steel winding gear connects to the movement holder. This bowl-shaped support facilitates smooth operation through the use of five spring-loaded ball bearings positioned along the edges, allowing the movement to rotate freely as part of the bezel-winding sequence. Technical design follows established marine chronometer practices for the period, prioritizing accurate timekeeping for navigational calculations. The combination of the two-day power reserve and the stabilized gimbal suspension reflects the requirement for performance under maritime conditions.

Identification

Serial number

25036

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.