New Richard Lange Zero Restart “Referenzuhr”


Richard Lange Zero Restart

Lange’s Richard Lange family of timepieces is dedicated to the scientific aspects of horology with a focus on precise timekeeping. With resettable subsidiary seconds, the Richard Lange “Referenzuhr” carries on a tradition dating to the early 19th century. Actuating the push piece at 2 o’clock instantly resets the seconds hand to zero, where it remains so long as the push piece is depressed, while the movement keeps running.

This sleight of hand (pun intended) is achieved via a vertical clutch that reengages when the push piece is released, restarting the seconds hand instantly. This complication facilitates synchronising watches and clocks at different locations: the actuation of the push piece synchronises the seconds hand of the instrument with that of a reference clock exactly when its hand passes the 60-seconds mark (“zero”). This action “stores” the time of the reference clock and allows it to be transferred to other timekeeping instruments. In 19th century Dresden, the Mathematics and Physics Salon was the official “keeper of time”, responsible for precisely determining the local time and making it available to the city’s population. In those days, the correct time was calculated on the basis of astronomical observations. The result was then transferred to a high-precision pendulum clock in the salon. Thereafter, the reference time was saved with especially accurate pocket chronometers and then “carried” to the public clocks. It was also communicated to persons and authorities who needed to know the precise time; astronomers, watchmakers and railway officials all subscribed to the timekeeping service.

With its off-center subsidiary seconds, Richard Lange “Referenzuhr” is reminiscent of a historic precursor made in 1811 – a pocket chronometer known to have been used for synchronization purposes by the timekeeping service. It was crafted by Johann Heinrich Seyffert who did more to promote precision horology in Dresden than any other watchmaker. His most prominent customer, naturalist and explorer Alexander von Humboldt, purchased one of Seyffert’s chronometers for his acclaimed Latin American expedition.

The Richard Lange “Referenzuhr” features a large balance wheel with eccentric poising weights and a Lange balance spring developed and manufactured in-house. It beats at six semi-oscillations per second (21,600 vph). A sapphire caseback allows a clear view of the technical finesse within: both the zero-restart lever mechanism and the winding train are visibly arranged above the three-quarter plate (see image below).

The Richard Lange Zero-Restart “Referenzuhr” will be produced in a limited series of 50 watches in platinum priced at 49,000 euros, and 75 pieces in pink gold priced at 39,500 euros.

Technical information appears below the images, which may be enlarged with a click.

Richard Lange “Referenzuhr”
Richard Lange “Referenzuhr”
Richard Lange “Referenzuhr"
Richard Lange “Referenzuhr”
Richard Lange “Referenzuhr” technical information
Leave a Reply