- Why would inventing a motor irritate anyone?
And how did Faraday invent the motor in the first place?
Well, I'll tell you, and along the way
I'll tell you about a strange theory of spiraling currents,
a claim of plagiarism, and a totally useless motor.
Ready?
Let's go.
♪ Electricity ♪
♪ E-lectricity ♪
♪ Electricity ♪
♪ E-lectricity ♪
- In 1820, a Danish man named Oersted
made a startling discovery.
When current runs through a wire,
it can force a compass to point in a circle around the wire.
Now, a compass is just a thin magnet on a pivot,
so Oersted had proved that electricity
and magnetism are linked.
What was incredibly confusing to people
was that the current went in a straight line
and the magnets made circles around the wire.
Oersted's solution was that the current
was really spiraling down the wire.
This brings us to England
and men named Michael Faraday and his mentor, Humfry Davy.
Humfry Davy was a famous chemist
and laughing gas aficionado,
who was arguably the most famous scientist
in all of Europe at the time.
Eight years previously, Davy had injured his eye
and hired Michael Faraday, a young, uneducated,
and poor bookbinder's apprentice, as his assistant.
By 1820, Davy was promoted
to president of the Royal Institution of London
and Faraday had been promoted
to the position of chemical assistant
and was conducting some of his research
independently of Davy.
Both Davy and Faraday,
and frankly every other scientist in Europe,
heard about Oersted's experiment
and tried to figure out what it meant.
Davy wrote his brother that, "I've ascertained,
"repeating some vague experiments of Oersted's,
"that the battery is a powerful magnet.
"I am deeply occupied in this."
In April of 1821, Davy started to collaborate
with his friend William Wollaston on the problem.
Wollaston had agreed with Oersted
that the current must spiral down the wire.
They spent many hours trying to come up with an experiment
that would demonstrate the spiraling motion,
but to no avail.
In the summer of 1821, Faraday was asked to write
an overview of the latest developments
in electricity for a journal.
As was his way, he decided to recreate the experiments
that he read about.
Through doing Oersted's experiment,
Faraday determined that the force
was circular around the wire,
not spiraling, as Oersted thought.
He decided that, strange as it may seem,
the current seemed to travel straight down the wire
and somehow it made a circular force
on a magnet around the wire.
In return, Faraday also postulated that a magnet
would create a circular force on a current-carrying wire.
In other words, "A wire ought to revolve
"around the magnetic pole
"and a magnetic pole around the wire."
On September 3rd, 1821,
Faraday proved that magnets create a circular force
on a current-carrying wire with a simple experiment.
He had a wire drop down on a cup full of mercury,
mercury is a conducting fluid,
with a permanent bar magnet in the center.
When he closed the switch, the wire spun continuously.
Supposedly, Faraday shouted, "There they go, there they go!
"We have succeeded at last!"
Technically, Faraday had just invented the electric motor.
An electric motor converts electricity into motion.
Of course, it wasn't a particularly practical motor,
as it didn't do any useful work,
unless you wanted to electrically stir mercury.
Luckily, Faraday didn't invent the motor to do any work.
He invented it to demonstrate
the nature of the electromagnetic force.
As a motor, it was useless.
As a demonstration of magnetic fields,
it was quite efficient.
Faraday published his work
on October 1st, 1821, to great acclaim.
But within a week,
people said he was plagiarizing his material
from Humfry Davy's friend, William Wollaston.
Faraday wrote to Wollaston, "I'm anxious to escape
"from unfounded impressions against me.
"And if I've done any wrong, then I may apologize for it."
Wollaston wrote back and claimed to be unoffended.
However, Wollaston did not publicly defend Faraday
and Humfry Davy publicly attacked him.
It's hard to know almost 200 years after the fact
why people did what they did and how they felt about it.
Most modern researchers feel that Davy
was jealous of his protege's success
and felt that Faraday was too low class and uneducated
to be an independent researcher.
However, it's also possible
that Davy felt justified in his anger.
Faraday was a person that Davy had plucked from obscurity,
and he did not give credit to his benefactor.
And it is true that Davy and Wollaston
had been trying to make a spinning device
before Faraday did, although with a different motivation.
Finally, it isn't clear that Davy really understood
what Faraday was proving with his experiment.
Davy's brother said that his objections to Faraday were,
"An act of justice to Dr. Wollaston."
It's quite possible Davy felt that way
for the rest of his life.
In 1826, Humfry Davy fell ill
from using too much laughing gas
or inhaling too many dangerous chemicals in a laboratory
and retired from his work as a chemist.
He died three years later.
Meanwhile, Faraday was eager to continue
his studies of electricity.
But instead, he was basically forced by the government
to study how to make better optical glasses,
a study that he found particularly fruitless,
saying that the only results were his own nervous headaches.
The first person to really take Faraday's idea
to the next level was a retired soldier
and boot-maker named William Sturgeon.
Sturgeon actually invented
one of the first practical motors in 1834.
First, however, he focused on another thing
Faraday mentioned in his paper:
that a helix of wire acts like a bar magnet.
How William sturgeon invented
the first practical electromagnet
is next time on "The Secret History of Electricity.
♪ Electricity ♪
♪ E-lectricity ♪
♪ Electricity ♪
♪ E-lectricity ♪
- Thanks for watching my video.
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Thanks, have a good day!
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