Atmos I, perpetual clock, J.L. Reutter for Compagnie Générale de Radio, France, 1930's

23,6 x 17,5 x 14,3 cm

In 1928 Jean-Lèon Reutter, engineer at Neuchatel, developed the first Atmos pendulum, renamed Atmos 0. This project was based on a clock with few building elements, which was charged through a glass container filled with mercury. Due to the temperature changes, it rotated the cylinder to which was connected and loaded the spring, which would then provide the necessary force for the watch to function.

In 1929, the French Compagnie Générale de Radio put Reutter in charge of a department dedicated to the design, development and production of the Atmos 1.

This model differed from the previous one for greater attention to details and the addition of ammonia to the thermo-sensitive mix that allowed the watch to be charged. The Atmos 1 is probably the rarest model, as there are fewer than 2000 products. It was also the only one to be produced in France.
In 1935 Jaeger-LeCoultre, who had been producing movements for Atmos 1 for a few years, acquired the rights and moved production to Switzerland. After an initial phase, in which Jaeger-LeCoultre patents a new charging system, the production of the Atmos 2 begins. The pendulum remains unchanged stylistically and operatingly, except for some design changes.

The genius of the project, its unique lines, as well as the ability to immediately strike the observer, made the Atmos a legendary pendulum. As a witness to its success, we see that Jaeger-LeCoultre’s Atmos is owned by various figures from the world of politics and entertainment, even becoming one of the official gifts of the Swiss Confederation. (source:


Condition: (UV-checked)

- The clock in good and working condition (a movie is available: link).

- The case and dial with some corrosion all-over and minor traces of use.

- The balance tube does not hang perfectly above the hole.

Estimate: € 5000 - € 10000