Jeager Lecoultre Atmos Clock

famous atmos clock by the house jaeger-lecoultre in gilded brass, enamelled annular dial with four digits, perpetual movement based on atmospheric pressure, circa 1950/70 in perfect working order delivery 50 euros Perpetual movement. a little magical, requiring no reassembly. The Atmos clock was invented at the end of the 1920s by the engineer Reuter, and operated at the time with a barometric capsule which wound up the movement, thanks to tiny differences in atmospheric pressure. (Hence the name)… The Jaeger Le Coultre brand bought the Patent at the time, and has continued manufacturing for over 90 years. The power source for the Atmos clock consists of a hermetically sealed Vidie capsule containing a gas, ethyl chloride. This gas expands in a membrane when the temperature increases which has the effect of compressing the coil spring. When the temperature drops, the gas condenses and the spring relaxes. It is this mechanism that perpetually powers the pendulum. Thus, an Atmos can operate for years without any human intervention. A simple variation of one degree (for a temperature between 15 ° C and 30 ° C) or a pressure variation of 3 mm Hg is enough to power the pendulum for two days. To operate the pendulum with this modest source of energy, the mechanism is designed with the minimum possible friction, which is why it does not include oil in its cogs. Time is measured using a pendulum which consumes less energy than an ordinary pendulum. Indeed, it performs a single oscillation per minute which is sixty times less than a conventional pendulum or 14,400 times less than a wristwatch. Sixty million Atmos combined consume less energy than a fifteen watt light bulb! The balance is suspended from an extremely fine elinvar wire. The twisting of this wire makes it possible to retain and then drive the balance wheel successively in one direction then in the other. Invented by Charles-Édouard Guillaume, Nobel Prize winner in physics, this wire, made of an alloy very insensitive to temperature changes, is artificially aged according to a secret process.