Re: bell wire
"silver lizard-hide insulated wiring"
That made me laugh out loud! My house was built in 1970 and I have a lot of "silver lizard-hide insulated wiring" and also grey plastic coated (crumbling with age) with cloth mesh underneath!
I guess that the builder used whatever he had laying around. Bastard!
Currently replacing all of that crap with High temp Romex (yellow) in the walls, and BX in the attic with ground wire included. All of the outlets have three prongs but had no ground wires! Also no cable clamps going into the circuit breaker panel.