On Saturday, 21 November 2015 08:55:35 UTC, Brian-Gaff wrote:
I've always fancied one of those mechanical door bells you used to see in
UpstairsDownstairs with brass plungers and bits of string and pulleys and
stuff. I wonder if anyone makes them?

No pulleys.
Where do you suppose the term "bell crank" comes from?
https://en.wikipedia.org/wiki/Bellcrank