Clocks that run on air; Flash back Under the Hammer.
IT WAS in 1928, a Neuchatel engineer called Jean-Leon Reutter built a clock driven literally by air.
But it took the Jaeger-Le Coultre workshop a few more years to convert this idea into a technical form that could be patented - and to perfect it to such a degree that the Atmos practically achieved perpetual motion.
In 1936, production at Atmos began inside a hermitically sealed capsule with a mixture of gas and liguid expanding as the temperature rises and contracting as it falls, making the capsule move like a concertina. This motion constantly winds the mainspring only one degree in the range between 15 and 30 degrees centigrade being sufficient for two day's operation.
The balance for example is 150 times slower than the pendulum in a conventional clock. So it's not surprising that 60m Atmos clocks together consume no more energy that one 15 watt light bulb.
All its other parts, too, are not only of the highest precision, but also practically wear free. An Atmos can expect to enjoy a service life of 600 years, although with today's air pollution, a thorough cleaning is recommended.
Every Atmos is still made by hand and with some models, a clock takes a whole month to produce - not counting the five weeks of trial and adjustment that every Atmos has to undergo.
Only then were the Jaeger-Le Coultre master watchmakers happy enough with the state of things to confirm it with a signature and allow another Atmos to leave the workshop. After which, many end up in the very best homes.
The Atmos has had the honour to be associated with great statesmen, royalty and other renowned people, including John F Kennedy, Sir Winston Churchill, General Charles DeGaulle and Charlie Chaplin and, who knows, maybe you!
There is evidence of overlapping in all Le Coultre models, there are no absolutes of serial numbers and calibre numbers. The Atmos II and the Atmos III production went from 1936 until 1955. The Atmos IV is Le Coultre's shortest full production run ever, the Atmos VIII is the last of the genuine Reutter design Atmos made and production stopped late in 1983 when Le Coultre redesigned the Atmos.
They are not antigue, but interesting, complicated and e xpensive.