[fragmede]

What blows my mind that we absolutely take for granted today is insulated wires. The technology and supply chain to mine or to find into metal and also to farm cotton and wool and formed that into protective tubing before the advent of plastic insulation. The amount of technology that goes into making a "simple" USB-cable beggars belief if you stop to think about it. Even a simple #2 wooden pencil with an eraser on top is beyond the knowledge of one person to produce, nevermind a USB-c cable!

[delaminator]

In Victorian London, electricity was distributed around the home using bare wires with an air gap. It was 32v though.

Later it was superseded with lead wrapped in paper, until the Knob and Tube system. This comprised of single-insulated copper conductors installed within walls and ceilings, this wiring was encased in porcelain insulating tubes with cloth-lined sleeves.

One knob for Live and one knob for Neutral. The wires were held in place by porcelain knobs nailed to the house frame. Where wires passed through wood framing, they were threaded through porcelain tubes to prevent them from contacting the wood.

[ipcress_file]

My house once had knob and tube wiring. Over the past 15 years I have replaced most of what I assume is the second-generation cloth-covered wiring (which dates back to the 40s, 50s, and 60s). Every once in a while, I come across the insulators from an older electrical system, but most of the wire that went with those insulators was pulled out long ago. The only remains are short bits of wire that were wrapped around the insulators.

[lisper]

https://en.wikipedia.org/wiki/Knob-and-tube_wiring

[jacquesm]

I found some of that in a very old farmhouse. It looked like a very good way of setting fire to a structure.

[jacquesm]

I have a cable here that is interesting. When I first saw it I thought how strange, a cable that is multi-stranded bare wire for this application (connecting a camera). Then I looked at it under a microscope and realized not only is it insulated wire, it is shielded wire. Mindblowing. I pity the people that have to handle that stuff.

https://down-ph.img.susercontent.com/file/sg-11134201-7repx-...

[raphman]

Indeed.

Small addendum: at least in Germany, early telephone wires (up until the 1950s?) were wrapped in paper, drenched in oil. The bundles were then enclosed in a lead-copper alloy to protect them from moisture.

https://commons.wikimedia.org/wiki/File:KabelbaumFMAachen_49...

[Aloha]

Well, and the first really 50 years of telephony - you were probably as likely to have an uninsulated line as an insulated one.

Remember that the first telephones were 1-wire with a ground return, and that configuration was quite common until the early 40's.

[NetMageSCW]

Reminds me of the (not entirely accurate) story of someone trying to make a cheeseburger from scratch and realizing it required most of modern civilization.