Electrified oil lamp?

Pardon the tipsy look, the milk glass top had been held on with a screw tightener and I didn't screw it back in for the pictures. It was also ivory in color until I washed it. Anyway the whole lamp is about 30" tall. The base looks like ivory but I was wondering if it might be alacite? There are no markings anywhere on the lamp that I can see. The glass top looks like it had some kind of a lid or cover that clipped on somehow with the indentations. Most of the stuff found with this were from the 1950's to 1960's but of course it could be earlier or later. It has a cord and had a bulb so it is electric but I don't know if it was converted or ? I don't see a way to rotate pictures so I'll go try to rotate my originals if that will help. Thanks for anything you can tell me about this.