Can anyone tell me What this is
This item is solid brass and looks to be a piece from the 50's or 60's maybe. Not sure. The top is 4 1/4 inches in diameter. The height is 3 5/8 inches and the little window is 1 1/2 inches in diameter. Elliot Eros is stamped on a disc in the window. It has a north point and the needle points north but no East, West or South stamped on the plate. I assume it is a compass but what kind and how do you get into it.