Movement record · United States
Hamilton 992
Partially verifiedBridge-layout railroad-grade movement
Technical specifications
- Diameter
- 16 size
- Height
- Not recorded in the sources consulted
- Jewels
- 21
- Frequency
- 18,000 vph (2.5 Hz)
- Power reserve
- Approx. 40 hours
- Winding
- Stem wind
- Setting
- Lever set
- Escapement
- Swiss lever
- Balance
- Bimetallic compensation balance in earlier production
- Complications
- Subsidiary seconds
Identification features
- Grade number marked on the movement
- Lever setting revealed under the bezel
Known variants
- Later 992B with alloy hairspring
- Variants across long production
Servicing notes
Cleaning, lubrication, mainspring and pivot work belong with a qualified watchmaker working from calibre-specific documentation. Conserve original parts: replacing a worn component with a modern substitute changes the object, and refinishing plates or dials destroys evidence.
General guidance only. Antique movements should be serviced by a qualified watchmaker.
Historical significance
The predecessor of the 992B and one of the defining American railroad grades of the early twentieth century.
Related photographs
No confidently matched photograph of this subject has been found yet. These photographs show a closely related record, and are not examples of the type described on this page.
Sources & references
- de Carle, D., Watch and Clock Encyclopedia
- Period trade material catalogues and calibre reference compilations (edition-dependent)
- Published manufacturer technical documentation where available
Where sources disagree, the disagreement is stated rather than resolved silently.