< Jaeger-LeCoultre >
Inspired by Gustav Klimt’s master piece, The Waiting , the new Atmos clock combines the skills of the artistic crafts with the fascination exercised by the clock
Jaeger-LeCoultre’s Atmos is a mechanical clock which does not need to be wound manually. It gets the energy it needs to run from temperature and atmospheric pressure changes in the environment, and can run for years without human intervention.
The first Atmos clock was designed by Jean-Léon Reutter, an engineer in Neuchâtel, Switzerland, in 1928. This noncommercial prototype, which predated the Atmos name but is now known unofficially as Atmos 0, was driven by a mercury-in-glass expansion device. The mechanism operated on temperature changes alone. In 1929, Compagnie Générale de Radio (CGR) in France began manufacturing the first commercial model, Atmos 1, which used a mercury and ammonia bellows power source. In 1935, Jaeger- LeCoultre took over production of Atmos 1 while it developed a second design which used the present ethyl chloride power source. This model, later named the Atmos 2, was announced in 1936, but problems delayed full production until mid-1939. Subsequent models were based on this design. To date, over 5,00,000 Atmos clocks have been produced.
Atmos’ power source is an internal hermetically sealed capsule containing a mixture of gaseous 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 temperature variation of only one degree in the range between 15 and 30 degrees Celsius, or a pressure variation of 3mmHg, 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 1/30th the rate of the pendulum in a grandfather clock.
The fifth work in the series of Atmos clocks created in tribute to Gustav Klimt is inspired by The Waiting, part of the artist’s famous frieze adorning Stoclet House, a mansion built by a Brussels banker. The original marble and coloured stone mosaic has been faithfully rendered by a meticulous marquetry motif covering the glass crystal cabinet. This exceptional model, which will be produced in a strictly limited 10-piece edition, combines the skills of the artistic crafts cultivated by the Manufacture with the fascination exercised by the Atmos clock. The latter’s apparently mysterious operation has for 80 years symbolised one of the most successful attempts to invent perpetual motion.