Any one know what this is? Our daughter and husband bought a piece of property and when they cleaned it up they found this. They saved it because they thought it was interesting.

The slates you see inside appear to be adjustable maybe ? I have not taken the time to research it at all but when I looked at it I thought it might be a Drag line ....or something to do with mining....or something like that. Husband thought so to. It is metal and big. You can I think see the size from the chain link fence it is in front of.

I think the kids are going to put Christmas light on it..Whatever it is.