This table clock features a gilded bronze cabinet with glass sides, containing a white porcelain face and an atmospheric clock mechanism.

The ATMOS brand identifies it as a mechanical clock made by Swiss firm Jaeger-LeCoultre. The originality of this clock resides in the fact that it does not need to be wound: it winds itself using energy from changes in temperature and atmospheric pressure, via a sealed capsule containing a mix of liquid and gaseous ethyl chloride that expands when the temperature rises, compressing a coiled spring. When the temperature drops, the gas condenses and the spring is released. This continual movement winds the mainspring. The adjustment mechanism is a torsion pendulum, which uses less energy than a standard pendulum. The clock can thus run for many years with no human intervention.

The first Atmos brand clock was designed by Jean-Léon Reutter, an engineer from Neuchâtel, Switzerland, in 1928. Jaeger-LeCoultre began production of the Atmos I on 27 July 1935.

Amelia Aranda Huete