Okay, I KNEW I had forgotten something.
The oldest type of surface mount wiring are single cloth covered conductors wound around each other, mounted on glass or porcelaine insulators. This type of wiring has become really rare, maybe i'll retrofit such an installation and then post a pic of it.
In the 1950ies and maybe earlier they had brass clad wires (looked like conduit but was more a cable). The cloth seems to be just wrapped around the conductors, not woven, and the rubber is as brittle as can be. I usually tend to rip out every piece of that kind of wiring, or if unavoidable wrap the entire exposed length of conductor at devices with PVC tape. Same stuff with a softer metal sheathing and an additional cloth covering as a top layer was available for damp locations.
Nowadays either trunking (PVC or metal) is used or Romex is directly stapled to the walls. Very common during remodels/renovations! About my entire room except for the ceiling light and a single receptacle is wired like that. Our staples are what Paul described as "saddles" and have always been.
Everything is stapled like that, especially phone wiring. If the subscriber doesn't provide conduit when the phone line is installed you get the wires stapled to the wall.
A common way to add ground wires is to run 4 sq. mm ground wires from the panel along the baseboards to each receptacle.
I also know that there were special zip cord staples with a single nail going into the groove between the conductors.
In damp environments open conduit systems are used, i.e there are no bent pieces of conduit, in bends the Romex just hangs in mid-air. The conduit is intended mostly to keep the cable from making contact with the wall.
Concerning Diazed fuses: There were fast and slow ones, now they've been replaced by "general purpose". However, one of the scandinavian language (can't remember which one) clearly states "slow".
Hope I didn't forget anything.
