A. Lange & Söhne: Lange 1 Tourbillon Perpetual Calendar Lumen

The tourbillon is one of the most sophisticated complications in watchmaking—even though its original purpose, to counteract the effects of gravity on pocket watches, is hardly relevant anymore in wristwatches. However, this does not prevent watchmakers from continually reinterpreting this fascinating mechanism. Sometimes, it even remains hidden from the viewer’s gaze.

A. Lange & Söhne: Hidden Away – Lange 1 Tourbillon Perpetual Calendar Lumen

However, the complication is not always apparent at first glance: On the “Lange 1 Tourbillon Perpetual Calendar Lumen” by A. Lange & Söhne, only the word “Tourbillon” on the dial indicates that the movement’s escapement rotates continuously—until, in a signature feature of the manufactory, it is stopped so that the watch can be set to the exact second.

Both the movement and the stopping mechanism can be observed through the sapphire crystal in the back of the 41.9-millimeter platinum case. The new L225.1 automatic caliber also features an unusual perpetual calendar with an outer month ring and a retrograde day-of-the-week display at 10 o’clock—all date indications advance in a single jump.

The energy for this is supplied by the white-gold rotor, whose outer segment—made of platinum—provides additional momentum. Lange has also developed particular expertise in the field of luminous material, which charges beneath the semi-transparent dial in the “Lumen” models.

Limited to 50 pieces, the “Lange 1 Tourbillon Perpetual Calendar Lumen” offers a unique instrument-like look at night. (MSRP: €550,000)