the leyden jar زجاجة ليدن

The leyden jar was one of the earliest condensers made , and consisted of a glass jar partly lined on the inside and outside with metal foil . they are its plates , while the dielectric between the plates is glass . a metal knob was connected to the inside metal foil by means of a chain which hung loosely and the jar given a charge by connecting the terminal of a wimshurst machine to the knob . a violent electrical shock is obtained if the knob is touched after the jar is charged , as the large charge stored passes through the body to the earth . the leyden jar was used as a scientific in the eighteenth century when this effect was first discovered . the sense of humour enjoyed by the Abbe Nollet , a French scientist , may perhaps be gleaned from the fact that he lined up hundreds of monks , connected them together by wires , and discharged a leyden jar through them ; the monks are reputed to have all jumped into the air together as a result of the shock .
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