Subject: electromagnetism and relativity

If two wires stand one along the other there is no force between them
(except a very weak gravitational force). However if the 'sea' of
electrons begins to move with an averge velocity v there will be
a more powerful magnetic force.

My question is what happens in the refference frame of one who
moves along the wires with speed v (so that relative velocity to the
electron gas would be nil)? I know that somehow special theory of
relativity deals with this, but i can't figure out how.

Re: electromagnetism and relativity