The history and working of the Atmos clock

To run the clock on it’s small amount of energy needed, everything inside the Atmos has to work in a as friction-free a manner as possible. For time keeping it uses a torsion pendulum hanging on a wire as thick as a hair which consumes less energy than an ordinary pendulum. The torsion pendulum executes only two oscillations a minute thus giving you also a relaxing mood while viewing this beautiful clock.

The first clock powered by changes in atmospheric pressure and temperature was not by Jean Louis Reutter but it seems by Cornelis Drebbel in the early seventeenth century.
Drebbel built as many as 18 of these clocks, the 2 most notable being for King James VI & I of Britain, and Rudolf II of Bohemia. The King James clock was known as the Eltham Perpetuum, and was famous throughout Europe. Look:https://sites.google.com/site/aboutdrebbel/Home
Cornelius Drebbel was on par with Galileo etc. You must read about this genius. Mostly forgotten in our time.

The original Atmos clock was designed by Jean-Léon Reutter, a Neuchatel engineer in 1928. This prototype is now named unofficially as Atmos 0, was driven by a mercury-in-glass expansion device. The mechanism operated on temperature changes alone. He died in 1971 without notice.

In 1929, Compagnie Générale de Radio (CGR) in France began manufacturing his first commercial model, now named Atmos 1, which used a mercury and ammonia filled U tube and the movement now know as the Cluses movement. In 1935, Jaeger-LeCoultre took over production of Atmos 1.
It improved on the movement with the caliber 30-A movement and developing at the same time a second design with J.L. Reutter which used the present ethyl chloride power source. This model, later named the Atmos 2  had a  slow start as the bellows was not reliable through the first production runs.
About 7000 Reutter Atmos clocks were produced. The Atmos 2 started at serial 7000 and was phased out around serial 25000.