Bell & Ross Vintage 123 Pink Gold Jumping Hour
© Bell & Ross
Jumping hours (“Heures Sautantes”) is the name for digital hour indication on the dial.
In a small window, usually at the top of the dial, there is a disc with the hour numerals, which is advanced jumping every hour.
Analogous to jumping hours, but referring to the second hand, which then moves forward every second. (In watches with conventional balance frequency, e.g. 28,000 A/h, the hand moves in fractions of a second). The display of a hand advancing by seconds requires more constructive effort.
See: Dead-beat seconds