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How Luigi Galvani Invented The Battery And Made A Dead Frog Jump

How did a Galvani make a dead frog jump?  And how did that lead to the battery?  And, hey, didn’t Volta invent the first battery?  Well, I’ll tell you and along the way I will talk about professional misconduct, a surprising accident, the inspiration for Frankenstein and the building block of life.



Table Of Contents

Why Galvani was Playing with Electricity

Galvani and the Shocked Dead Frog

Galvani and Atmospheric Electricity

Galvani and the First Battery

Video Script Download


Why Galvani was Playing with Electricity

A portrait of Luigi Galvani
A portrait of Luigi Galvani

Sometime in 1790 or 1791 an Italian professor of anatomy named Luigi Galvani was playing with electricity machines and hoping to find something interesting to publish. 

See, Galvani was a member of the Academy of Sciences of the Institute of Bologna and he needed to submit a research paper every year.  For the previous four years he had published work on the hearing of various animals. 

However, that year his work was “poached” from a rival so Galvani needed a new topic – and quickly.

Galvani thus turned to the “newish” field of electricity and got several assistants to help him. 

He had static electricity machines that you could spin to produce large static charges and jars called Leyden jars that could store the charge and give it in a terrifying jolt when you connected them in a circuit. 

One day, unrelated to his electricity experiments, he happened to put a dissected headless frog on the table while his assistants were running these electrical experiments. 

He never said why he why he was cutting up frogs in the first place. 

A popular myth is that he was making frog soup for his sick wife.  However, it seems much more likely that he was dissecting the frog for an anatomy lecture (he was an anatomy professor!) 

Galvani and the Shocked Dead Frog

Experiment De viribus electricitatis in motu musculari
Experiment De viribus electricitatis in motu musculari

Anyway, a frog was on a table near an electric machine. 

This is how Galvani described what happened next, “I had dissected and prepared a frog and I had put it on a table where there was an electric machine.

As soon as one of my aides, by accident, touched the internal nerves of the frog with a scalpel, at once he saw all the muscles go into violent convulsions.” 

Galvani was deeply surprised by the frog “jumping” and did a series of bizarre and macabre experiments, like frogs in a jar and frogs in a circle to determine what would make the frog dance. 

He also moved on to other animals and found that all animals would display this behavior to some extent.

Galvani (or honestly his assistant) accidentally discovered two things with this. 

First, they found that frog legs are an extremely sensitive “machine” for detecting electricity – superior by a factor of five thousand to anything non-biological available at the time.  

Secondly, and more importantly, Galvani created the study of how electricity works in living systems.  He found that muscles contract with electricity and nerves send messages with electricity. 

In truth, electricity is the building block of living systems.  We think with electricity, we hear and see and smell with electricity, our hearts pump with electricity, and our muscles move with electricity. 

This is not just true for frogs, ALL animals’ living functions are electrically based.  

Galvani called it “animal electricity” and felt that all living beings had it inside them, especially in the nerves and muscles. 

Now it took a further 150 years to really understand the complex beauty of the organic system but Galvani started us on that path!

Galvani and Atmospheric Electricity

Late 1780s diagram of Galvani's experiment on frog legs
Late 1780s diagram of Galvani’s experiment on frog legs

Galvani then decided to move his frog experiments outside to see if thunderclouds could make the frog jump as well as static electricity would. 

This was 38 years after Benjamin Franklin flew his kite in a storm so he was not surprised to find that the frog jumped theatrically in thunderstorms. 

However, something else happened that was truly unexpected, sometimes the frog legs would jump on clear days with no static electricity involved AT ALL. 

What was going on?  At first, Galvani wondered if the frog collected atmospheric electricity from past storms. 

However, Galvani was a very careful scientist and realized it had nothing to do with the weather it had to do with the outdoor gate!  See, he had iron railings surrounding the garden that he hooked his frogs on. 

He also used copper hooks to transport the frogs. 

It was this combination, the iron and the copper that caused the frog to convulse. 

When he took the frog inside he could make a frog dance with just a piece of copper and iron!  Crazy huh? 

This is a major find, putting both copper and iron into a frog’s body produces electricity – with no rubbing globes or thunderstorms in sight. 

Galvani decided that the frog produced electricity because it had been alive in the past – he thought he was reanimating the frog ala Frankenstein (whose author was inspired by Galvani’s research by the way)!

Galvani published his work in 1791 and it became an international sensation, especially among anatomists. 

Suddenly, there was a new way of examining how muscles move and nerves communicate. Galvani’s theory of “animal electricity” created a link between electricity and what makes things alive. 

Galvani made the spark of life literal.

Galvani and the First Battery

Galvani discovered that frog’s legs suspended on a copper hook would twitch when touched with a zinc probe, leading to the idea of ‘animal electricity’. This was later disproved by Volta.
Galvani discovered that frog’s legs suspended on a copper hook would twitch when touched with a zinc probe, leading to the idea of ‘animal electricity’. This was later disproved by Volta.

Galvani didn’t know it, but he had also inadvertently invented the first battery – the acid of the frog’s leg reacted with the copper to add electrons and reacted with the iron to remove electrons. 

The electrons then flowed through the frog’s leg from the copper to the iron making the frog leg jump.  In terms of physics, it was a completely useless battery as it discharged inside itself. 

This is why most people do not consider Galvani’s “invention” a battery.  

However, there was a man named Alessandra Volta who was supposed to be Italy’s leader in electricity who became obsessed with jealousy over Galvani’s fame. 

Volta started a war with Galvani, which led to him building the first non-biological battery. 

This is the battery that changed the world, which is why electromotive power is measured in Volts. 

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