Knob-and-tube wiring (sometimes abbreviated K&T) is an early standardized method of electrical wiring in buildings, in common use in North America from about 1880 to the early 1940s. It consisted of single-insulated copper conductors run within wall or ceiling cavities, passing through joist and stud drill-holes via protective porcelain insulating tubes, and supported along their length on nailed-down porcelain knobinsulators. Where conductors entered a wiring device such as a lamp or switch, or were pulled into a wall, they were protected by flexible cloth insulating sleeving called loom. The first insulation was asphalt-saturated cotton cloth, then rubber became common. Wire splices in such installations were twisted together for good mechanical strength, then soldered and wrapped with rubber insulating tape and friction tape (asphalt saturated cloth), or made inside metal junction boxes.
I guess you missed my point.
30 years ain't ain't nothin in the grand scheme of things.
The evolution of residential plumbing and electricity is a relatively new phenomenon.
Electricity did not come to the area that I live in until about 1937........I've spoken to old timers here who remember life before electricity, and then they tell me in the beginning you were lucky if you had one light bulb.