Amphora Iron Ages amphorae spread around the ancient Mediterranean world, being used by the ancient Greeks and Romans as the principal means for transporting and storing grapes, olive oil, wine, oil, olives, grain, fish, and other commodities. They were produced on an industrial scale until approximately the 7th century AD. Wooden and skin containers seem to have supplanted amphorae thereafter. They influenced Chinese ceramics and other East Asian ceramic cultures, especially as a fancy shape for high-quality decorative ceramics, and continued to be produced there long after they had ceased to be used further west. Besides coarse amphorae used for storage
Leyden jar used in demonstrations. The jar is constructed out of a glass cup nested between two fairly snugly fitting metal cups. When the jar is charged with a high voltage and carefully dismantled, it is discovered that all the parts may be freely handled without discharging the jar. If the pieces are re-assembled, a large spark may still be obtained from it. This demonstration appears to suggest that capacitors store their charge inside their dielectric. This theory was taught throughout the 1800s. However, this phenomenon is a special effect caused by the high voltage on the Leyden jar. In the dissectible