Pottery Pre-Dynastic lid, possible Naqada II from El Adaima. A complex locking device once secured this lid to a low flat pottery base something like a soup bowl. First, three or four strings were attached to a small perforated disk - designed like a modern button. Next, the lid was turned upside down and the string were passed through a tiny hole at the top - leaving the disk inside. The strings now projected out of the top of the lid, were wrapped around the base of the vessel (sealing the two piece together).