115 Volts or 220 Volts ?

Before we give Mr Edison too much credit for any AC current distribution, see below

http://www.teslasociety.com/ac.htm

Higher voltage means less current for a given number of watts (power) so you can use smaller wire. That's why automobiles changed from 6 volts to 12 volts. Aircraft, where weight is important, have gone to 24 volts. This is a pain because you can't use jumper cables from your car to start the plane if the battery is dead.

You can kill yourself easily with 115 volts. The trick is to make a good solid connection with the hot wire and ground. If you just brush lightly against the hot wire, so that little current flows, 220 feels about like 115.