UPDATE: WOW! I didn't think anyone would actually respond, but check out all the great ideas in the comments. Thanks! You've inspired me to dig a bit deeper and figure this out for sure. Next stop, Antiques Roadshow, where it is revealed that this once held princely spittoons, and is worth 86 bajillion dollars.
since we moved in and I think the reason I've never moved it is
precisely because I have no idea about its intended purpose.