Old setback thermostat

[Inspectorjoe]

I always assumed automatic setback thermostats were a fairly recent invention, dating back to maybe the first 70's energy shortage. I was wrong. I found one (abandoned in place) that's nearly 70 years old.

http://static.flickr.com/49/116640327_f704a9bd11_o.jpg

[Chad Fabry]

That's very cool