by roberta naas | February 10, 2014 | Watches & Jewelry
1. From Jaquet Droz, this Twelve Cities watch ($31,200) is crafted in 18k rose gold and offers elegant jump-hour indication at 12:00. Created in a limited edition of 88 pieces, the timepiece houses a self-winding mechanical movement with 12 time zones indicated by city names via an aperture at 6:00 on the enamel dial.
2. This A. Lange & Söhne Zeitwerk watch ($68,900) is crafted in 18k pink gold and houses an in-house mechanical movement, the Lange Caliber L043, powered by a constant-force escapement. It features a patented barrel design and offers jump-hour indication via an aperture on the left and jump-minute indications via a harmoniously balanced aperture on the right of the dial. Seconds are indicated via a subdial at 6:00 and power reserve is indicated at 12:00.
3. Cartier’s Rotonde de Cartier jumping-hours watch ($38,600) is crafted in 18k gold and houses the 217-part Calibre 9905MC with jumping hours and trailing minutes with disc mechanism. It offers 65 hours of power reserve, and each movement is individually numbered.
“On the outside, the jump hour looks very simple, but inside it is really complicated,” says Gaeton Guillosson, North American president of German watch brand A. Lange & Söhne. Deriving its name from its distinctive design, the jump-hour watch is one of the most classically elegant watchmaking complexities on the market. In a jump-hour watch (also referred to as jumping hour) the hour indication is in a digital format that is displayed via an aperture, most often at 12:00, which automatically changes on the hour.
Today’s jump-hour watches are based on a concept that was developed and patented in 1882 by Austrian engineer Josef Pallweber, who created a digital display for pocket watches that used numbers on rotating disks in addition to classic pointers. It became a popular complication for pocket watches throughout the late 19th and early 20th centuries, and interest in them has sparked over the past few years.
Because of their complexity, jump-hour timepieces are offered by only about a dozen top watchmaking brands as part of their ongoing collections. Generally, the indication works via a complex rotating disk system within a more complex movement consisting of several hundred components. An elaborate feat to build, jump hours require more time to assemble than standard timepieces—with some requiring several days’ worth of a watchmaker’s attention. But watch enthusiasts consider the end result well worth the effort, as the overall look of the jump hour makes the watch a much-coveted item.
A. Lange & Söhne’s intricate Zeitwerk, which holds two patents, features a combination of jump-hour and jump-minute indications on the dial via two harmoniously balanced apertures. A great deal of research and development went into creating the movement, so that the jump hour and the jump minutes change with precise synchronization each hour. According to Guillosson, the watch is so unusual that there is a waiting list for it wherever in the world it is sold.
1. Harry Winston’s 45.6mm Ocean Tourbillon jumping-hour watch ($217,300) is crafted in 18k white gold and houses a 330-part mechanical manual-wind movement with jump-hour indication at 12:00 and tourbillon escapement at 6:00. With twin barrels, the watch offers 110 hours of power reserve. The dial portion is made from black sapphire.
2. From Bulgari, this 43mm Octo Bi-Retro watch ($18,200) is crafted in a stainless steel case with a black ceramic bezel. The automatic movement offers jump hours at 12:00, with a retrograde minutes indication and a retrograde date indication at 6:00.
3. This David Yurman Classic® jumping-hours limited-edition watch ($8,900) houses a self-winding automatic Dubois Depraz movement with ETA base, and offers a jump-hour indication at 12:00. The 43.5mm black PVD case with gray galvanic dial and smoked sapphire crystal make a chic presentation. The watch—made in a limited edition of 100 numbered pieces—features a center minutes hand, sub-seconds dial, and is water-resistant to 30 meters.
4. Authentic watchmaking tools courtesy of Audemars Piguet.
Other high-end companies offering classic jump-hour watches generally display only the hour as a jumping digit, and indicate the minutes via a long central minutes hand that rotates around the dial in typical pointer fashion. In the Harry Winston Ocean Tourbillon jumping-hour watch with a house-made caliber, the pointer-style minute hand has been specifically designed so that the hour window is never blocked. The concept took the brand’s research and development team more than 1,500 hours to devise and bring to fruition.
Additionally, some brands opt to combine the jump hour with other alluring watch complications—including the melodious minute repeater or the always-in-motion retrograde. In fact, in its Octo Bi-Retro jump-hour watch, Bulgari combines the jump-hour complication with retrograde minutes (wherein the minute hand travels along an arc, and when it reaches the end of its indication, it returns back to the beginning of the arc).
No matter which jump-hour rendition a watch brand offers, those who covet a purist approach to horological accomplishments can’t help but be drawn to their complexity and the sheer beauty and simplicity of the look.
“The jump-hour watch offers a very unusual way of reading time,” says Guillosson. “So even if you are not a watch collector, this look can really appeal to you because it is something completely different.”
photography by jeff crawford; styling by terry lewis