Introduced in 1994, the LANGE TOURBILLON “Pour le Mérite” by A. Lange & Söhne incorporates a number of fascinating technical details never before seen in a wristwatch. One of them is the going train drive via fusee and chain. This complicated mechanism optimises the rate accuracy of the watch and is visible through an aperture in the three-quarter plate.
A highly sophisticated planetary gearing system keeps the power to the going train steady even while the watch is being wound.
The delicate tourbillon mechanism also serves the purpose of improving rate accuracy by offsetting the disruptive effect of gravity. The rotating cage is suspended by two pivots between two diamond endstones.
It turns about its own axis once a minute and can be precisely balanced with tiny counterweights. The fascinating movement of the tourbillon cage can be observed not only through an aperture in the dial but also through the sapphire-crystal caseback.
The 38.5 mm diameter case in gold or platinum houses the manual-winding calibre L902.0 boasting lavish decorations and finishing painstakingly carried out by hand. The solid silver dial features Arabic numeral hours markers and blued hands. In addition to the eye-catching tourbillon complication at 6 o’clock, the dial has two sub-counters: for indicating running seconds at 9 o’ clock and for power reserve at 3 o’clock.
The A. Lange & Söhne LANGE TOURBILLON “Pour le Mérite” watch was limited to 150 watches in 18-carat yellow gold and 50 in platinum. It was built between 1994 and 1998.
Model: A. Lange & Söhne LANGE TOURBILLON “Pour le Mérite”
Reference 701.001: 18-carat yellow gold
Reference 701.005: Platinum
Manually wound, constant- force fusee-and-chain transmission with planetary gearing, tourbillon regulator
18-carat yellow gold or platinum
Diameter: 38.5 mm
Height: 10.0 mm
Sapphire-crystal glass and caseback
Platinum version: Limited to 50 pieces
18K yellow gold version: Limited to 150 pieces
Courtesy: Lange Uhren GmbH