On Tue, 22 Jun 2010 06:18:54 -0700, Pavel314 wrote:

This is a theoretical electrical question, not something I actually plan
to do. Say somebody wants to run a new circuit from the breaker box to
one special outlet, like for a microwave oven or window air conditioner
or something like that. Being an ecconomical sort, this guy decides that
instead of buying the proper gauge wire for the job, he'll use up some
14 gauge wire which is lying around from a previous job, but run two hot
lines and two ground lines in parallel, as diagrammed below.

That's essentially the way it's done in the UK; wiring is run such that
outlets sit on a ring circuit rather than a radial from the service panel
(consumer unit in UK parlance). See:

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

I'm sure it violates all sorts of rules this side of the Pond :-)

cheers

Jules