Antique Cast Iron Posnet Lead Smelting Pot 3 Leg Makers Mark 1800's Smooth bottom.  I can't make out the letters on the side. Purchased from an estate in Tennessee at a noted historical home.  Through much research I am convinced this is exactly as I've described it. Size shown in photos.  It also appears to have been used many times to melt lead and other metals. The hollow handle is a clear indicator of the tradesmen using a small wooden pole inserted into the handle to lessen the intense heat on the hand.