Glossary · Mechanism
Train count
The tooth and pinion counts that set a movement's beat rate.
Explanation
From the wheel and pinion counts and the escape wheel teeth the vibrations per hour follow arithmetically — 18,000 vph for a five-beat train, 14,400 for a slower antique train. Knowing the count is essential before timing a watch, since a timing machine set to the wrong rate reports nonsense.