Atmos Clock

The Atmos is the brand name of a mechanical clock manufactured by Jaeger LeCoultre in Switzerland which doesn't need to be wound up. It gets the energy it needs to run from small temperature changes in the environment, and can run for years without human intervention.
Its power source has a hermetically sealed capsule containing a mixture of gas and liquid (ethyl chloride), which expands into an expansion chamber as the temperature rises, compressing a spiral spring; with a fall in temperature the gas condenses and the spring slackens. This motion constantly winds the mainspring. A variation in temperature of only one degree in the range between 15 and 30 degrees Celsius is sufficient for two days' operation.
 

In order to run the clock on this small amount of energy, everything inside the Atmos has to work in as friction-free a manner as possible. For timekeeping it uses a torsion pendulum, which consumes less energy than an ordinary pendulum. The torsion pendulum executes only two torsional oscillations per minute, which is 150 times slower that the pendulum in a conventional clock.

In 1928, an engineer in Neuchatel, Switzerland named Jean-Leon Reutter built a clock driven by a mercury-in-glass expansion device. The device rotated a cylinder which then wound the mainspring by ratchet. The mechanism operated on temperature changes alone. It took the Jaeger-LeCoultre workshop a few more years to convert this idea into a technical form that could be patented.

An early predecessor is Cox's timepiece, a clock developed in the 1760s by James Cox and and John Joseph Merlin. The oldest predecessor still running today is the 1864 Beverly Clock.
 
The Atmos- Atmospheric- almost Perpetual Motion Clock & a strange history
Thanks to his friend César de Trey , (also a contributor to the creation of the Reverso), Jacques-David LeCoultre discovers the fascinating "eternal" clock. After a detailed scrutiny of its mechanism, he notes that only the finest watchmakers will be able to rise to this technical challenge. Jean-Léon Reutter shares this conviction and after years of research was issued a patent in 1926. In 1928, the the first prototypes of a clock that draws its energy from the slightest atmospheric variations is presented. Entirely made within the Manufacture since 1936, the Atmos has become a legend of its time. Its prestige earns it status as the official gift of the Swiss government.
 
Initially it was made in a variety of designs, but by 1937 it was decided to give so unique a mechanism a distinctive outward appearance. Accordingly, the old designs were withdrawn and replaced by the one still in use. It is a simple yet elegant open-dial model made of brass, set on a brass base and covered by a detachable case consisting of four crystal sides and a crystal top set in a brass framework. As of 1954, neither the mechanism nor the design had been patented. The name Atmos, however, which is always used to describe this atmospherically operated clock, has been registered in the United States Patent Office, as the property of Establissements Ed. Jaeger of France.
 
Link: How the Atmos clock works
this link has a very nice close up picture of the Jaeger LeCoultre Atmos clock
Jaeger LeCoultre Atmos Clock, Model 528-6, Cleaned, Serviced, Timed, Runs Great

Jaeger LeCoultre Atmos Clock, Model 528-6, Cleaned, Serviced, Timed, Runs Great

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JAEGER LECOULTRE ATMOS CLOCK 1950'S W  ORIGINAL BOX & INSTRUCTIONS SER #74211

JAEGER LECOULTRE ATMOS CLOCK 1950'S W ORIGINAL BOX & INSTRUCTIONS SER #74211

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Jaeger LeCoultre Atmos Clock, Model 528-8, Cleaned, Serviced, Timed, Runs Great

Jaeger LeCoultre Atmos Clock, Model 528-8, Cleaned, Serviced, Timed, Runs Great

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Jaeger-LeCoultre Atmos Mantle Clock 540 13 Jewels Roman Numerals #647547 Swiss

Jaeger-LeCoultre Atmos Mantle Clock 540 13 Jewels Roman Numerals #647547 Swiss

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Vintage Le Coultre ATMOS ~ The Perpetual Motion Clock w Original Box

Vintage Le Coultre ATMOS ~ The Perpetual Motion Clock w Original Box

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Swiss Jaeger LeCoultre Atmos Perpetual Motion Mantle Clock 528-8 No Reserve

Swiss Jaeger LeCoultre Atmos Perpetual Motion Mantle Clock 528-8 No Reserve

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Mint Rare Nickle Plated! Jaeger LeCoultre Atmos 540 Elysee Mantel Clock- Working

Mint Rare Nickle Plated! Jaeger LeCoultre Atmos 540 Elysee Mantel Clock- Working

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Vintage Jaeger Le Coultre Atmos Clock Glass Cover #501497

Vintage Jaeger Le Coultre Atmos Clock Glass Cover #501497

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Vintage Le Coultre & Cie Swiss ATMOS mantel clock sqaure face cased 527...

Vintage Le Coultre & Cie Swiss ATMOS mantel clock sqaure face cased 527...

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LeCoultre Atmos Clock - in family for over 45 years

LeCoultre Atmos Clock - in family for over 45 years

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***Vintage Atmos LeCoultre Clock***

***Vintage Atmos LeCoultre Clock***

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JAEGER LE COULTRE - EARLY 1960's - 528-6 ATMOS CLOCK

JAEGER LE COULTRE - EARLY 1960's - 528-6 ATMOS CLOCK

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VINTAGE JAEGER LeCOULTRE ATMOS CLOCK CALIBER 528-8 SWISS MANTEL CLOCK S N 417183

VINTAGE JAEGER LeCOULTRE ATMOS CLOCK CALIBER 528-8 SWISS MANTEL CLOCK S N 417183

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Jaeger LeCoultre Baby Atmos Clock, 526-5, Cleaned, Serviced, Timed, Runs Great

Jaeger LeCoultre Baby Atmos Clock, 526-5, Cleaned, Serviced, Timed, Runs Great

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Vintage SWISS ATMOS Jaeger LeCoultre & Cie 15-Jewel 528 Mantle Clock W  papers

Vintage SWISS ATMOS Jaeger LeCoultre & Cie 15-Jewel 528 Mantle Clock W papers

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1989 Jaeger-LeCoultre Atmos Swiss Presentation Clock Cal 540

1989 Jaeger-LeCoultre Atmos Swiss Presentation Clock Cal 540

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Jaeger le Coultre Atmos 528-8 Perpetual Motion Brass Clock 393697 1970's

Jaeger le Coultre Atmos 528-8 Perpetual Motion Brass Clock 393697 1970's

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(1) New LeCoultre Atmos Clock Perpetual Motion Plaque! For 540, 528, 526, 519

(1) New LeCoultre Atmos Clock Perpetual Motion Plaque! For 540, 528, 526, 519

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LeCoultre Atmos Clock ? Serial Number 323060

LeCoultre Atmos Clock ? Serial Number 323060

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Atmos Lecultre Clock. Serial #277236

Atmos Lecultre Clock. Serial #277236

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