Complication · Timing
Seconde Morte (True Beat Seconds)
Partially verifiedA seconds hand that advances in one-second increments in a mechanical watch.
Definition
A seconds hand that advances in one-second increments in a mechanical watch.
Historical origin
Originally used in precision pendulum clocks (deadbeat escapement) and later adapted to watches.
How it works
A separate small train or a specialized jumper mechanism releases the seconds hand exactly once per second.
Commonly uses a 'star and flirt' or a second escapement wheel.
Pocket watch context
Found in high-grade scientific and observation watches of the nineteenth century.
Wristwatch context
A connoisseur's complication in modern watches from Habring2, Arnold & Son, and Jaeger-LeCoultre.
Identification
- A mechanical watch where the seconds hand 'ticks' like a quartz watch
Servicing notes
The jumper spring tension is critical; incorrect adjustment stops the watch.
General guidance only. Complicated mechanisms should be assessed and serviced by a qualified watchmaker or clockmaker specialist, not adjusted at home.
Diagram
Sources & references
- de Carle, D., Watch and Clock Encyclopedia
- Britten, F. J., Old Clocks and Watches and Their Makers
- Horological Journal (British Horological Institute), technical articles
Where sources disagree, the disagreement is stated rather than resolved silently.