I replaced a 1956 ceramic pull-chain lighting fixture in the basement (bare bulb), but can't get it to work. (My kids pulled the chain out of the old one, which used to work fine.)I wired a new one the same way, but it won't turn on. I replaced the new fixture with another new fixture, thinking the first one was defective, but it still won't turn on.

Coming out of the ceiling into the electrical box are two white wires that are joined together and capped--they were not connected to the original fixture; and two red wires, both of which were connected to one terminal on the old fixture (there are also two yellow wires that merely extended the length of those red wires).

I tested the two red wires. One showed it was hot, the other one was not. I wired the hot red to the brass screw on the fixture and the non-hot red to the silver screw on the fixture. It just won't work. The lightbulb does work, but not in that fixture.

No one at Home Depot has been able to figure it out and I can't find the answer on the web. Can you help me?