As mentioned, I posted this over at r/WhatIsThisThing, also. I thought some lovely historians may be able to help me as well.

I found this ball in the dirt at my grandparent's farm in middle Tennessee. It's incredibly rusty. It was caked in dirt, but we've cleaned it up a bit. It's got a faucet type thing on top, a hollowed out part in the middle with holes on each side. Here is a bottom view, also.

We can't find any specific markings on it, but its so covered in rust it is really hard to tell. This was in a plowed up piece of garden, so I wonder if it wasn't underground until recently. My mother thought it may be a well weight, as they had a well on the property when she was growing up, however, this was a ways away from the well that I remember, and the well has not been there for almost ten years. It's around ten pounds.