[North Coast Cab]

Couple things.
1) I would guess there was a problem in that circuit to begin with and thatis why the fxiture was removed and abandoned.
2) The fixture you installed is effectively drawing 200 amps which is a lot for an apartment light. You don't have any idea what else is on that circuit so it's very possible you are overloading the circuit.
3) I would go buy a $1 porcelain keyless socket, like the ones in your closet, and connect it with a $.50 light bulb. Use it for a few days and find out if the circuit is functioning properly. Then you can upgrade the fixture if things seem ok.