Famous ATMOS clock by the Jaeger LeCoultre brand, in a glass and 24 kt gold-plated case. Slightly smaller model in original Jaeger leCoultre box.The clock has a 15 jewels movement on bearings, numbered 75540, which is a low number. Calibre 526/5.Glass door to the front with original black text Jaeger-leCoultre.Year of manufacture based on serial number: 1950-1955. Numbers ring in original, off-white colour with Arabic numerals and stripes.The timepiece is powered by a self-winding system that works on temperature differences.Clock runs fine.The clock comes with a copy of the original user manual in several languages (Dutch, English, French, German, Italian, Spanish, Swedish and Japanese).ATMOS in good condition, slim design with lovely rose gold-plating.The numeral ring has signs of wear.Measurements:Height: 22 cm.Width 18 cm.Depth: 14 cm.Weight: 3.6 kg.Condition: good, box has traces of brown tape.The lot will be packaged with care and sent registered and insured.In 1928, the Swiss engineer Jean-Léon Reutter invented the Atmos clock. The first designs functioned using the expansion of mercury. In 1936, Jaeger LeCoultre decided to buy the design from Reutter and immediately patented it. Since that time, Jaeger Le-Coultre has produced the Atmos clock in series. The company was officially renamed Jaeger-LeCoultre.The clock was a wondrous invention, since the timepiece ran on air. One degree difference in temperature was enough to make the timepiece work for two days. The mechanism is based on an air-tight, gas-filled glass capsule.Originally filled with air, it is now filled with ethyl chloride (C2H5CL). Minimal temperature differences change the gas volume in the capsule: it contracts or expands. This "breathing" provides the spring with energy. It does not require any batteries, electricity, hand force, sun, wind or kinetic energy. The Atmos clock is extremely economical and runs for 48 hours on a temperature difference of just one degree Celsius. The temperature differences of one day provide enough energy for a month's accurate time display, the clock can even build up a power reserve for a year.The power reserve in mechanical watches usually lasts for days. The 309 parts of the movement are perfectly adjusted for minimal friction, no lubricants are necessary. Everything is so finely adjusted that the weight of a small insect can stop the hands. The spring only moves two times a minute instead of the usual 300 times a minute in a wristwatch (which uses 250 times more energy). This clock uses 60 million times less energy than a 15 watt light bulb. The Atmos table clock has been the official state gift of Switzerland for over fifty years.(source: Rikketik magazine)