With its ZERO-RESTART function, an innovative seconds hand resetting mechanism, the A. Lange & Söhne RICHARD LANGE “Referenzuhr” enriches the line of observation watches dedicated entirely to precise time measurement.
The RICHARD LANGE watch family is fully devoted to the scientific facets of horology with a focus on the utmost degree of precision. With its resettable subsidiary seconds, the RICHARD LANGE “Referenzuhr” continues this tradition.
The actuation of a push piece above the crown causes its seconds hand to jump to zero and wait there as long as the push piece is depressed. During that time, a vertical disc clutch assures that the ongoing measurement of time is not interrupted – the movement keeps running. When the push piece is released, the seconds hand restarts instantaneously.
This ZERO-RESTART function is very useful for stopping events of short durations. It is also ideal for 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.
The A. Lange & Söhne RICHARD LANGE “Referenzuhr” watch pays homage to a stronghold of time measurement that played in important role in 19th-century Dresden: the timekeeping service of the Mathematics and Physics Salon.
As the “keeper of time”, this scientific institution was responsible for precisely determining the local time and making it available to the city’s population. So in a sense, it was the predecessor of present-day atomic clocks and time signal transmitters. But in those days, the correct time had to be calculated on the basis of astronomical observations.
The result was then transferred to a high-precision pendulum clock in the salon. Thereafter, this 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. Subscribers of the timekeeping service included astronomers and watchmakers as well as officials of the nascent railway system.
With its off-centre subsidiary seconds, the dial of the RICHARD LANGE “Referenzuhr” is reminiscent of a historic precursor made in 1811 – a pocket chronometer known to have been used for synchronisation 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 now acclaimed Latin American expedition.
The A. Lange & Söhne RICHARD LANGE “Referenzuhr” is equipped with the manual-winding calibre L033.1. It features a large balance wheel with eccentric poising weights and a Lange balance spring developed and manufactured in-house. Beating at a frequency of six semi-oscillations per second, it delivers the precision that can be legitimately expected of an instrument designed to serve the sciences.
Visible through the sapphire-crystal caseback, both the ZERO-RESTART lever mechanism and the winding train are visibly arranged above the three-quarter plate.
The RICHARD LANGE “Referenzuhr is a limited edition of 50 watches in platinum and 75 in pink gold.
Model: A. Lange & Söhne RICHARD LANGE “Referenzuhr”
Lange manufacture calibre L033.1, manually wound, crafted to the most exacting Lange quality standards and largely decorated and assembled by hand; precision-adjusted in five positions; plates and bridges made of untreated German silver; balance cock engraved by hand
No. of movement parts : 276
No. of jewels : 34
Screwed gold chatons : 1
Escapement : Lever escapement
Oscillation system : Shock-resistant glucydur balance with eccentric poising weights; superior-quality balance spring manufactured in-house, frequency: 21,600 semi-oscillations per hour, precision beat adjustment system with lateral setscrew and whiplash spring
Power reserve : 38 hours when fully wound
Movement dimensions Diameter: 30.6 millimetres; height: 6.8 millimetres
Time display in hours, minutes, subsidiary seconds with stop seconds and ZERO-RESTART mechanism, power-reserve indicator
Crown for winding the watch and setting the time, push piece for resetting the seconds hand
Pink gold (Ref 250.032)/ Platinum(Ref 250.025)
Diameter: 40.5 millimetres
Height: 11.2 millimetres
Glass and caseback: Sapphire crystal (hardness 9)
Solid silver, argenté (Ref 250.032)/ Solid silver, rhodié (Ref 250.025)
Ref 250.032: Pink gold hands, subsidiary seconds hand in blued steel
Ref 250.025: Rhodiumed gold hands, subsidiary seconds hand in blued steel
Limited edition of 75 watches in pink gold (Ref 250.032) & 50 watches in platinum (Ref 250.025)
Hand-stitched crocodile strap, red-brown (Ref 250.032); Hand-stitched crocodile strap, black (Ref 250.025)
Buckle: Lange prong buckle in solid pink gold (Ref 250.032); Lange prong buckle in solid platinum (Ref 250.025)