ROMEX Cable

I'm trying to do some research for a paper for a local jr. college in the field of building inspection.

I am looking for historical pictures and history on non-metallic sheathed cable or ROMEX cable.

What was used before Romex, Knob and Tube maybe? Romex is a trade name licensed to General Cable Corporation in 1922. Some of the old cables had insulated wire that were wrapped individually in a paper that was impregnated with a black substance, may be tar or wax, to keep out moisture them marked white or black. Two wires, one black and one white, were rapped together in the same kind of paper wrapping. Be on that, I don't have any information and I don't know where to look.

Anything you can add would be helpful.

Warren -- PS. Sure, enjoy your electrical inspection section


Joe Tedesco, NEC Consultant