What are these?

[Gene South]

What are these? Appears to be a old monitoring system of some sort from the 1970's (House built in 1978). There was one of these in every room and also one in the attic. They appeared to be mechanial or electro-mechanical but no wiring was seen. Two had a metal ear sticking out that read "REWIND".

[Stephen G]

Fire Alarm, and they would be 40 years old, my mom had them before the smoke detectors of the 70s became mandatory. Pull on the lever sets the bells. Very loud...

[Steven Turetsky]

Heat detectors

[Gene South]

Stephen, the ones in you Mom's house had no wiring, right? I did not find any wiring. Wonder how they worked? Looked like a wind-up.

[Stephen G]

Gene, no wires at all. Clock spring, wind it up, or rewind
Steven is right as well.
The heat from the flames in a fire would melt that brass/bronze ring allowing the clock spring to let the clapper go, and as as mentioned, very loud,,,that first pic looks to have a cosmetic cover, maybe to change the sound




Heat detectors

[Gene South]

Thanks guys!