Description:
A tall, narrow, cylindrical glass jar with a brass rod extending along its inner axis held in place by a cork at the bottom of the jar and another cork near the top of the jar through which the brass rod goes. The rod does not go through the cork at the bottom: the cork does have a perforation, but it is currently filled with a thin, pencil-like piece of wood with a string or cable tied to it. The surface of the glass right outside the bottom cork is covered in metal sheet.