Matt W. Barrow wrote:
"Some Other Guy" wrote

It's just a hell of a clever plumbing arrangement. Add heat at one part
(by burning gas, whatever), and another part gets cold:

http://www.gasrefrigerators.com/howitworks.htm

Ever wonder why they never became popular?

On the contrary, it became popular as hell after it was invented
in Sweden in 1922 because reliable electricity was not available
in the world at that time.

They're still widely used in cottages. The really cool thing about
them (apart from the temperature) is that they're deathly quiet.

Damn thing just sits there hissing quietly.

....so you can get your cold beer after landing on the lake at your cottage
in Northern Ontario, Canada [official rec.aviation.piloting content]