[Amps] what is a 4 wire 240VAC service?

[Roger Parsons]

There are a couple of things I don't understand: :-)

(1) When it became clear, probably close to 100 years ago, that 120V was too low a voltage to efficiently power room (or tubes with handles) heaters and similar equipment, why did North America not follow the rest of the world and move to a 230V system? That is, a 3 wire 230V AC service.

(2) What bright spark decided that black was a good colour choice for the hot wire?

Actually, there are many other things I don't understand, but those will do for now.

73 Roger
VE3ZI