The creation of the Richard Lange Tourbillon "Pour le Merite" watch is closely related to Johann Heinrich Seyffert (1751-1817), a prominent watchmaker, the one who greatly contributed to the progress of precision horology in Saxony.
Seyffert’s timepieces enjoyed great success at the royal court and among scientists. The famous explorer and naturalist Alexander von Humboldt was also among the admirers of the watchmaker’s creations. He used a Seyffert chronometer during his expedition to South America. According to the explorer’s notes, the chronometer provided accuracy to four or five seconds a day. When it was kept stationary, its rate accuracy was even better - to less than one second in 24 hours. Even today, such level of precision is truly impressive.
The dial of the regulator watch is completed with three intersecting circles for the time indications. The caliber of the watch incorporates a fusee-and-chain mechanism providing the constant transmission of power. The timepiece, bearing the serial number 93, served as the blueprint for the Richard Lange Tourbillon “Pour le Merite” watch.
The face of the new A. Lange & Sohne watch demonstrates three overlapping off-centre circles. The biggest is the minute circle. The slightly smaller sub-dials are for the seconds and hours. The dial layout has been inspired by the precision regulators, used since the 18th century for calibration by timekeeping services, observatories and manufactories for synchronizing new timepieces.
The round cut-out in the seconds sub-dial is traversed by the minute scale and by the recessed tourbillon bridge. It shows off the tourbillon cage. It is interesting to mention that the tourbillon is presented in its entirety only in the period from 12 to 6 o’clock.
At 6 o’clock, the dial segment completed with the Roman numerals VIII, IX, and X instantaneously pivots into the aperture, thus making the hour scale complete. The ingenious switching mechanism is used to generate this motion. It is responsible for the dial segment to be advanced by 90 degrees in increments of six hours. It means that the timepiece tells the time unambiguously during the morning and the evening hours.
At 12 o’clock, the hours dial segment instantaneously vanishes and the tourbillon is exposed in all its beauty for the six hours to come.
With help of a patented stop-seconds mechanism, it is possible to simply halt the tourbillon by pulling the crown, so the time can be set to one-second accuracy. On the case-back side, the tourbillon is found in a diamond endstone secured in a screwed gold chaton. The same noble setting highlighted the iconic Lange pocket watches relevant to the manufactory’s highly-esteemed “1A” quality category.
The unique fusee-and-chain transmission, a smart implementation of the principle of levers, is responsible for equalizing the gradually waning force of the mainspring and maintaining the effective torque, this way also maintaining the constant amplitude of the balance, during all 36 hours of the power-reserve. The planetary gearing makes this constant force delivery kept with no interruption even when the timepiece is being wound.
The heart of the Pour le Merite watch, the novel hand-finished Lange manufacture calibre L072.1, 33.6mm in diameter, with a frequency of six semi-oscillations per second, a classic screw balance, and a recalculated balance spring, is synonymous to the utmost in precision.
The exceptional A. Lange & Sohne Richard Lange Tourbillon "Pour le Merite" watch features a stately platinum or pink-gold case that measures 41.9mm in diameter. It is coupled with a hand-stitched crocodile strap.
The platinum version of the timepiece is strictly limited to 100 pieces.