Skip to content
The Encyclopedia of Horology

Marine chronometer · Two-day marine chronometer

Charles Frodsham Marine Chronometer

Partially verified

According to the auction catalog, this marine chronometer by Charles Frodsham dates to circa 1850 and is housed in a brass-bound rosewood three-tier box with external drop handles. The chronometer is mounted in a gimbaled brass bowl with a locking slide. It features a silvered dial with champlevé radial Roman numerals, an outer minute track, subsidiary seconds, and a power reserve indicator. The source describes the movement as a 56-hour manual-wind mechanism with a fusée and chain, Harrison's maintaining power, a spring-detent escapement, and a free-sprung helical balance spring.

Charles Frodsham marine chronometer in a gimbaled brass bowl within an open wooden three-tier box.
Charles Frodsham marine chronometer in a gimbaled brass bowl within an open wooden three-tier box. — Antiquorum. Rights pending — permission not yet requested. Original source

Catalogue identity

Source
catalog.antiquorum.swiss
Category
Marine chronometer · Two-day marine chronometer
Maker / attribution
Charles Frodsham
Reference
Not recorded
Catalogue / lot identifier
29
Source-reported date
circa 1850
Country
United Kingdom
Source-reported serial
1754

Source-reported attribution and specifications are not independent authentication. A listing does not establish present ownership, current display, availability or permission to reproduce.

Object description

Case Construction and Exterior

The marine chronometer is housed in a three-tier rosewood and gilt brass case featuring brass-bound corners and external drop handles. The internal assembly includes a gimbaled brass bowl equipped with a locking slide mechanism.

The case features an internal ivory signature plaque located in the upper section. The source reports that the glazed top section of the case is missing.

Evidence for this section
  • “Three-tier case, brass-bound corners, external drop handles, glazed top missing”
  • “upper section with ivory signature plaque”
  • “gimbaled brass bowl with locking slide”

Dial and Visual Appointments

The silvered dial includes champlevé radial Roman numerals and an outer minute track featuring Arabic five-minute numerals. The time is indicated by blued steel fleur-de-lys hands.

The dial displays subsidiary seconds and a power reserve indicator. The source notes the dial is slightly oxidized and slightly scratched.

Evidence for this section
  • “silvered dial with champlevé radial Roman numerals, outer minute track with Arabic five minute numerals, subsidiary seconds and power reserve indication”
  • “blued steel fleur de lys hands”
  • “Dial: 2-6-8-01 Very good Slightly oxidized Slightly scratched”

Movement and Technical Specifications

The movement is a manual-wind, 56-hour mechanism featuring a fusée and chain with Harrison's maintaining power. Components include a brass half-plate, ring-turned pillars with blued steel screws, and a barrel secured under a crescent-shaped bridge.

Regulation is provided by a spring-detent escapement and a cut bimetallic compensation balance with peripheral temperature adjustment screws and mean time adjustment nuts. It further utilizes a two-armed subsidiary compensation device mounted on the balance pivot and a free-sprung helical balance spring with inner and outer terminal curves.

Evidence for this section
  • “manual wind 56 hour going marine chronometer”
  • “Brass half plate, cut away for the barrel secured under a crescent-shaped bridge, ring-turned pillars with blued steel screws, fusée and chain with Harrison's maintaining power”
  • “spring-detent escapement, cut bimetallic compensation balance with peripheral temperature adjustment screws and mean time adjustment nuts”
  • “two-armed subsidiary compensation mounted on the balance pivot above the balance and with 2 perpendicular adjustment nuts on long screw threads, blued steel free-sprung helical balance spring”

Open research questions

  • Verify the production date alignment of serial number 1754 with Charles Frodsham records.
  • Investigate if the 'Custom-made' grading in the source refers to specific non-standard modifications to this unit.

Source evidence

Recorded claims and source quotations for Charles Frodsham Marine Chronometer
FieldSource-reported valueSource quotation
MakerCharles Frodsham, UK“Brand Charles Frodsham, UK”
Case Number1754“Case No. 1754”
Power Reserve56 hour“manual wind 56 hour going marine chronometer with power reserve indicator.”
Dimensions155 x 155 mm“Diameter 155 x 155”
EscapementSpring-detent escapement“spring-detent escapement, cut bimetallic compensation balance”
Estimated Datecirca 1850“Year circa 1850”
Case Number1754“Case No. 1754”
Dimensions155 x 155 mm“Diameter 155 x 155”

Visible details

  • Chronometer mounted in a brass gimbal ring inside an open wooden box with brass corner reinforcements.
  • Brass-bound wooden case fitted with a side carrying handle and an upper lid prop arm.
  • Lid interior displays an applied rectangular nameplate inscribed 'CHARLES FRODSHAM 7, PAVEMENT, FINSBURY LONDON.'
  • Silvered dial features radial Roman hour numerals, subsidiary dials, and blued steel hands.

Research qualifications

  • The auction catalog notes that the glazed top of the three-tier case is missing.
  • Internal movement features including the fusée, spring-detent escapement, and balance assembly are not visible in the provided photograph.

Photograph identity and source facts were screened before import; rights clearance remains pending.

Consulted source

CHARLES FRODSHAM, UK, MARINE CHRONOMETER, WOOD AND GILDED BRASS | Important Modern & Vintage Timepieces | New York, October 18, 2026

Reviewed 2026-10-25 · Record 7c319bef55

Terms in this record

Glossary explanations for terms named in this object’s record.

Other two-day marine chronometer records