Insight | Jaeger-LeCoultre Atmos Clocks

Insight | Jaeger-LeCoultre Atmos Clocks

April 28th 2022

Jaeger-LeCoultre Atmos Clocks

Get familiar with the world famous ‘perpetual motion’ Jaeger-LeCoultre Atmos Clock

Even in the modern world today, objects that keep time need to be wound or charged and have some form of energy input, but this is not the case for Atmos clocks, they quite simply get their energy from the ‘atmosphere’. Dating back to the 17th century when the first idea came along from a chap called Cornelis Drebbel, it did not come into its own commercially until Jean-Léon Reutter, an engineer from Switzerland picked it up in 1928 and built a non-commercial prototype which predated the Atmos clock but was known as Atmos 0. It was the first model with a mercury-in-glass expansion device. Fast forward to 1935, when well-established watch firm Jaeger-LeCoultre takes over production of the Atmos 1 from Compagnie Generale de Radio following the design from Reutter, which housed a mercury and ammonia bellows power source. It was then developed into ethyl chloride by Jaeger-LeCoultre, and to this date, Jaeger-LeCoultre still manufactures models derived from the original.

 

Close up of the movement on the Jaeger-LeCoultre Atmos Clock showing the serial number 19967

Close up of a signed movement on an earlier model Atmos clock available at Jacksons antique

The clock is driven by a mainspring, wound by the expansion and contraction of a liquid and gaseous ethyl chloride in an airtight chamber called bellows. When the temperature rises, the ethyl chloride vaporises and expands, compressing a spring, and when the temperature falls, the gas condenses, and the spring expands. The continuous motion winds the mainspring, giving enough energy to run the entire clock. A 1-degree change in temperature is enough to run a modern Atmos clock for 4.3 days! As the clock requires such a small amount of energy to run, it is imperative that it is as friction-free as possible. For example, oiling the clock in the incorrect place causes too much friction for the clock to run, which is a common fault seen when serviced by a horologist with no prior knowledge of these timepieces.Atmos Clock

Jaeger-LeCoultre Atmos Clock in partnership with USA firm Gruen previously sold by Jacksons Antique

For timekeeping, a torsion pendulum is used as it consumes far less energy than an ordinary pendulum, and it twists on the end of the wire instead of swinging left to right. The motion rotates precisely 30 seconds in each direction for a full minute, which is 30 times slower than that of a typical long-case clock. Other than occasional servicing due to wear and tear, the clock literally runs itself without any human intervention, making them extremely hassle-free with a totally mesmerising silent skeletal movement. At Jacksons Antique, we pride ourselves on our Atmos clock collection, all of which are meticulously broken down, cleaned and serviced before they are offered for sale our collection.

Close up of the movement in the Jaeger-LeCoultre Atmos Clock

Close up of the 519 skeleton movement which is fitted in the majority of Jaeger-LeCoultre Atmos Clock

FOR HELP DATING YOUR ATMOS CLOCK PLEASE CLICK HERE FOR OUR GUIDE

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