Nepedia
Back to Discover
Fluent Reader
⚛️

Leyden jar

physical science Maturity 11-13 Next article →

A Leyden jar is a special tool used to store electric charges. It was the very first way people could collect and save electricity in large amounts. This was a huge deal for early science. Before this, it was hard to keep electricity for later use. The jar acts as a capacitor, which is a device that holds an electric charge.

Leyden jar showing construction
Leyden jar showing construction

Today, teachers still use these jars to show how electricity works in classrooms. They help us see the invisible power of electrostatics.

Leyden unit jar
Leyden unit jar

The jar works using a simple design with glass and metal. It is a glass jar with metal foil glued to the inside surface. Another layer of metal foil is glued to the outside surface. A metal rod or terminal goes through the lid to touch the inner foil. When electricity is added, the charge stays on the metal layers. The glass in the middle acts as a barrier that stops the charge from moving easily. This allows the jar to hold the energy until someone wants to use it.

Two different people discovered this tool around the same time in 1745. A German cleric named Ewald Georg von Kleist made the first discovery. He was working in a place called Pomerania. He used a small medicine bottle filled with alcohol for his experiment. He noticed the glass helped hold the electric charge inside. Later, a Dutch scientist named Pieter van Musschenbroek found it too. He worked at Leiden University in the Netherlands.

Dissectible Leyden jar
Dissectible Leyden jar

Scientists learned many things about the jar through accidents and tests. A lawyer named Andreas Cunaeus helped find a key secret. He held the jar in his hand while it was being charged. This caused him to receive a very powerful shock. He realized the hand was a vital part of how the charge moves. In 1746, a man named Johann Heinrich Winckler connected three jars together. This created a group of jars that worked as one unit.

Connecting many jars together led to the idea of a battery. Benjamin Franklin experimented with these setups between 1746 and 1748. He used eleven panes of glass with metal plates to build his own version. In 1749, he used the term "electrical battery" to describe them. He was inspired by the way a battery of guns is used in a salute. This is where we get our modern word for batteries.

Leidse flessen Museum Boerhave december 2003 2
Leidse flessen Museum Boerhave december 2003 2

Even though our tools have changed, the name Franklin chose is still used today.

409 words

Where will your curiosity go next?

Keep exploring at your chosen reading level.

🖼️ Images & Media (5)
File:Andreas Cunaeus discovering the Leyden jar.png
Andreas Cunaeus discovering the Leyden jar.png
File:Leidse flessen Museum Boerhave december 2003 2.jpg
Leidse flessen Museum Boerhave december 2003 2.jpg
File:Leyden jar showing construction.png
Leyden jar showing construction.png
File:Leyden unit jar.png
Leyden unit jar.png
File:Dissectible Leyden jar.png
Dissectible Leyden jar.png
More to explore

🔬 Go deeper

More advanced topics to explore

🪜 Step back

Simpler topics to build understanding

What is Nepedia?

A free, ad-free encyclopedia for children. Every article is written at five reading levels, so the same page works for a five-year-old and a fifteen-year-old — use the level switcher above to see this one change. No account needed to read.