To add an AC outlet, for example, you just drill a circular hole in the wall, tap into the wiring, add the outlet and you're set. If you don't want it, pull it out and plaster over it with more earth to seal the hole.
“But contrary to what some people seem to think, I was never a bully. I was just a hard man.”
“In 1833, protection was abandoned, and a tariff was established by which it was provided that we should, in a few years, have a system of merely revenue duties.”