The Atmos clock by Jaeger LeCoultre always has intrigued me. I really love the later models with a moonphase and in rhodium plated steel.
These clocks do not need a power plug or a winding key. Atmos clocks get their energy from temperature changes in the environment. The following explanation is grabbed from the Atmos wikipage, as I couldn’t say it better (in English at least):
“Its power source is a hermetically sealed capsule containing a mixture of gas 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 variation in temperature of only one degree in the range between 15 and 30 degrees Celsius 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 60 times slower that the pendulum in a conventional clock.”
As pictured on Atmos Adam’s website:
A bit of googling learned me that there are quite a number of Atmos collectors and freaks around. However, most Atmos clocks you will encounter on the collectors web pages and on ebay are gold plated. This has probably something to do with its price. The vintage models that are gold plated are very affordable. I have seen them going for 650-800 euro, probably the same range in USD, but importing them to another continent isn’t a good idea, since air-mail isn’t doing them any good. The rhodium plated models however, are much more expensive. I haven’t seen them below 3000 euro and a moonphase complication will add another 2000 euro at least. It would be fun to own one, even gold-plated give the price, but since I would like to place it in our living room, gold-plated is not the way to go 🙂 It simply doesn’t fit. I guess I will have to keep saving up or get a gold-plated one and keep it in our study.
Note (thanks Hessel): In 2008, the JLC Atmos celebrates its 80th birthday with three limited models. In these 80 years, JLC has manufactured more than 750 000 Atmos clocks. Click here to see a nice SIHH report on the Atmos specials (you need a login code for the WatchProSite!).
Click here for the official Jaeger LeCoultre Atmos pages: http://www.jaeger-lecoultre.com/la/en/watches/atmos-classique
Click here for a collector’s page on Atmos clocks: http://www.geocities.com/atmosclocks/
Click here for Atmos repairs: http://www.atmosclocks.com/index.html
Photos grabbed from various eBay auctions. The How-it-works description is from atmosadam.com. A great source of information for Atmos-adepts, make sure to visit this website.