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
LECOULTRE ATMOS CLOCK Classic 528-6 Nice Shape Working 15 Jewels Swiss

LECOULTRE ATMOS CLOCK Classic 528-6 Nice Shape Working 15 Jewels Swiss

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Swiss 528-6 Square Dial Le Coultre Atmos clock  Running

Swiss 528-6 Square Dial Le Coultre Atmos clock Running

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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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RARE! BEAUTIFUL ATMOS JAEGER LECOULTRE MANTEL CLOCK 528-8 - ROUND DIAL

RARE! BEAUTIFUL ATMOS JAEGER LECOULTRE MANTEL CLOCK 528-8 - ROUND DIAL

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1960'S FINE VINTAGE ATMOS "CHINOESE" BY MARINA PERPETUAL CLOCK JAEGER LE COULTRE

1960'S FINE VINTAGE ATMOS "CHINOESE" BY MARINA PERPETUAL CLOCK JAEGER LE COULTRE

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HERITAGE JAEGER LECOULTRE ATMOS MANTLE CLOCK WITH ORIGINAL BOX PERPETUAL MOTION

HERITAGE JAEGER LECOULTRE ATMOS MANTLE CLOCK WITH ORIGINAL BOX PERPETUAL MOTION

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VINTAGE 1960's LE COULTRE ATMOS JAEGER   MANTEL CLOCK

VINTAGE 1960's LE COULTRE ATMOS JAEGER MANTEL CLOCK

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Vintage LeCoultre Atmos Clock 528-8 Square face Working Condition SN 360530

Vintage LeCoultre Atmos Clock 528-8 Square face Working Condition SN 360530

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Jaeger LeCoultre Atmos 528-8 Clock

Jaeger LeCoultre Atmos 528-8 Clock

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Lecoultre Atmos clock Bellows

Lecoultre Atmos clock Bellows

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Le Coultre Atmos  clock replacement Bellow As Parts

Le Coultre Atmos clock replacement Bellow As Parts

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1972 LeCoultre Atmos Mantle Clock Model 528-8 Serial # 359010

1972 LeCoultre Atmos Mantle Clock Model 528-8 Serial # 359010

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Mid 1970's Jaeger LeCoultre ATMOS 528-8 Round Dial Clock- Working!

Mid 1970's Jaeger LeCoultre ATMOS 528-8 Round Dial Clock- Working!

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Modern Rounder Square Dial Atmos Jaeger LeCoultre Caliber 540 C1980?s

Modern Rounder Square Dial Atmos Jaeger LeCoultre Caliber 540 C1980?s

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Jaeger LeCoultre Atmos Clock Shelf

Jaeger LeCoultre Atmos Clock Shelf

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BEAUTIFUL ATMOS JAEGER LECOULTRE MANTEL CLOCK 528-8 - ROUND DIAL

BEAUTIFUL ATMOS JAEGER LECOULTRE MANTEL CLOCK 528-8 - ROUND DIAL

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Le Coutre Atmos Mantle Clock

Le Coutre Atmos Mantle Clock

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Vintage LeCoultre Atmos Swiss Made Mantle Clock caliber (528-8) AS-IS - No Reser

Vintage LeCoultre Atmos Swiss Made Mantle Clock caliber (528-8) AS-IS - No Reser

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  JAEGER LECOULTRE  CALIBER 528-8 ATMOS CLOCK

JAEGER LECOULTRE CALIBER 528-8 ATMOS CLOCK

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1957 Jaeger LeCoultre Baby Atmos 526-5 Perpetual Movement Mantle Clock15 jewels

1957 Jaeger LeCoultre Baby Atmos 526-5 Perpetual Movement Mantle Clock15 jewels

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