Leyden jar

The Leyden jar or Leiden jar is a kind of a battery. It is the oldest capacitor. This means it stores electrical energy between two electrodes. One of them is inside of a jar and the other one is outside. Ewald Georg von Kleist developed this system in Germany in 1744. The Dutch scientist Pieter van Musschenbroek in Leiden (Leyden) also invented it about two years later.