In British systems we always maintained correct tip and ring connections throughout.

Party line ringing has already been mentioned. Two-way party lines were once common in Britain, and as well as applying ringing to either tip or ring these also used a ground-start for outgoing calls, each subscriber having a button which he was instructed to press to get a dialtone. One party grounded the ring, the other the tip.

Many old step-by-step switches in both the U.S. and U.K. reversed polarity on the caller's line with supervision. Thus any of the older polarity-sensitive TouchTone pads would stop working once the called party answered.

Just think, had that situation continued, we could have escaped the "Press 1 for...., press 2 for....." frustration that we have to put up with nowadays! [Linked Image]