Many famous clockmakers were experimenting with “wandering hours” in the 18th century and Josef Pallweber later patented his design for a pocket watch with jumping hours and minutes in 1883. His design was licensed to IWC amongst others, but the boom for jumping hour watches didn’t really come about until the 1920s and coincided with the Art Deco movement. The complication fell out of fashion and remained so until the 1970s when the jumping hour made something of a comeback in both mechanical and quartz form. Many of the cheaper examples from this period are actually direct read watches comprising discs for hours, minutes and seconds that are all in constant motion but viewed through windows so that only the relevant part of each disc is shown.

Part of the complexity of creating a jump hour movement is the regulation of power that is transferred to the hour disc. Unlike a traditional time display which uses a constant force regardless of position of the minute or hour hands, the “snap” of a jumping hour only needs a delivery power for a short period each hour when the mechanism engages.

This sudden spike in required power potentially reduces the amplitude of the balance for the rest of the movement at this time, or increases it for the rest of the hour when no additional power is needed. A further potential problem to wearers is the precision with which the jump occurs; a slow or imprecise date change is forgivable to most people, but seeing the minute hand registering somewhere between 59 and 1 minutes during a jump would not be so easy to live with.

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