"Dave Plowman (News)" wrote:

Geoffrey S. Mendelson wrote:

As late as the 1960's London had FOUR different electrical systems with
different voltages and plugs.

Are you sure about that? There were several different socket outlets still
in use - 3, 5 and 15 amp all in either two or three pin.

2, 5 and 15A and they were all part of a single standard. Only the 2 and 5A
existed as 2 pin types.

http://en.wikipedia.org/wiki/BS_546

Graham