I found this weird metal cross-looking thing.?

When i was digging a swimming pool in the backyard my dad found this weird looking thing, it was covered in dirt and rust, it looked really old. The odd thing is that it is shaped like a cross without the small top piece and made of metal, the metal is not completely smooth it has some ridges. The long end is curved into a "O" at the bottom, the 2 arms sticking out of it both have this triangular thing coming out of the middle of them, and the top looks like its broken off. What could it possibly be? Also, is there someone i could contact in order to find out what this is?