WEBVTT

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At the dawn of the 19th century,

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in a cellar in Mayfair,

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the most famous scientist
of the time, Humphry Davy,

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built an extraordinary piece
of electrical equipment.

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Four metres wide, twice as long

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and containing stinking stacks
of acid and metal,

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it had been created to pump out
more electricity

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than had ever been possible before.

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It was in fact the biggest battery

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the world had ever seen.

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With it, Davy was about to propel us

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into a new age.

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That moment would take place at
a lecture at the Royal Institution,

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in front of hundreds
of London's great and good.

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Filled with anticipation,
they packed the seats,

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hoping to witness a new
and exciting electrical wonder.

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But what they would see that night
would be something truly unique.

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Something they would remember
for the rest of their lives.

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Using just two simple carbon rods,

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Humphry Davy was about to unleash
the true potential of electricity.

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Electricity is one of nature's
most awesome phenomena,

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and the most powerful manifestation
of it we ever see

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is lightning.

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This is the story of how
we first dreamed of controlling

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this primal force of nature,

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and how we would ultimately
become its master.

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It's a 300-year tale

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of dazzling leaps of imagination
and extraordinary experiments.

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Tens of thousands of volts
passed across his body

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and through the end of a lamp
that he was holding.

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It's a story of a maverick geniuses

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who used electricity
to light our cities,

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to communicate across the seas
and through the air,

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to create modern industry and
to give us the digital revolution.

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But in this film, we'll tell the
story of the very first scientists

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who started to unlock
the mysteries of electricity.

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It's as though
there's something alive in there.

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They studied
its curious link to life,

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built strange and powerful
instruments to create it

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and even tamed lightning itself.

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It was these men who truly laid
the foundations of the modern world.

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And it all started with a spark.

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Imagine our world
without electricity.

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It would be dark,

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cold and quiet.

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In many ways, it would be like
the beginning of the 18th century,

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where our story begins.

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This is the Royal Society in London.

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In the early 1700s,
after years in the wilderness,

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Isaac Newton
finally took control of it

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after the death of his arch-enemy,
Robert Hooke.

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Newton brought in his own people
to the key jobs,

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to help shore up his new position.

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The new head of demonstrations there
was 35-year-old Francis Hauksbee.

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Notes from the Royal Society in 1705

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reveal how hard Hauksbee tried

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to stamp his personality
on its weekly meetings,

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producing ever more spectacular
experiments to impress his masters.

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In November, he came up with this -

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a rotating glass sphere.

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He was able to remove the air
from inside it using a new machine -

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the air pump.

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On his machine, a handle allowed him
to spin the sphere.

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One by one,
the candles in the room were put out

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and Francis placed his hand
against the sphere.

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The audience were about to see
something amazing.

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'Inside the glass sphere,

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'a strange ethereal light
began to form,

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'dancing around his hand.

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'A light
no-one had ever seen before.'

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That's fantastic.

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You see a beautiful blue glow,
it's just marking out

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the shape of my hands,
but then going right round the ball.

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It's as though
there's something alive in there.

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It's difficult to really understand

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why this dancing blue light
meant so much,

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but we have to bear in mind
that at the time,

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natural phenomena like this were
seen to be the work of the Almighty.

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This was still a period when,
even in Isaac Newton's theory,

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God was constantly intervening
in the conduct of the world.

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It made sense for a lot of people

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to interpret natural phenomena
as acts of God.

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So when a mere mortal
meddled with God's work,

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it was almost beyond
rational comprehension.

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Hauksbee never realised the full
significance of his experiment.

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He lost interest
in his glowing sphere

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and spent the last few years
of his life

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building ever more
spectacular experiments

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for Isaac Newton
to test his other theories.

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He never realised
that he had unwittingly started

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an electrical revolution.

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Before Hauksbee, electricity
had been merely a curiosity.

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The ancient Greeks rubbed amber,
which they called electron,

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to get small shocks.

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Even Queen Elizabeth I marvelled

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at static electricity's power
to lift feathers.

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But now Hauksbee's machine

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could make electricity
at the turn of a handle,

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and you could see it.

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Perhaps even more importantly,
his invention coincided

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with the birth of a new movement
sweeping across Europe

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called the Enlightenment.

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Enlightened intellectuals
used reason to question the world

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and their legacy
was radical politics,

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iconoclastic art

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and natural philosophy, or science.

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But ironically,
Hauksbee's new machine

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wasn't immediately embraced
by most of these intellectuals.

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But instead,
by conjurers and street magicians.

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Those with an interest
in electricity

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called themselves electricians.

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One story tells of a dinner party
attended by an Austrian Count.

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The electrician had placed
some feathers on the table

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and then charged up a glass rod
with a silk handkerchief.

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He then astonished the guests
by lifting up the feathers

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with the rod.

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He then went on to charge himself up

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using one of Hauksbee's
electrical machines.

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He gave the guests electric shocks,
presumably to squeals of delight.

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But for his piece de resistance,

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he placed a glass of cognac
in the centre of the table,

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charged himself up again

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and lit it with a spark
from the tip of his finger.

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There was a trick called
the electrical beatification,

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in which the victim sits
on an insulated chair

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and above his head
hangs a metal crown

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that doesn't quite touch his head.

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And then if the crown
is electrified,

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then you get an electric discharge
around the crown

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that looks exactly like a halo,

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which is why it's called
the electric beatification.

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As England and the rest of Europe
went electricity crazy,

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the spectacles grew bigger.

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The more curious electricians

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started to ask
more profound questions,

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not only how can we make
our shows bigger and better,

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but how can we control
this amazing power?

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And for some, can this incredible
electrical fire

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do more than just entertain?

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One of the first early breakthroughs
would never have happened

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had it not been
for a terrible accident.

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This is Charterhouse
in the centre of London.

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Over the past 400 years,
it's been a charitable home

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for young orphans
and elderly gentleman.

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And sometime in the 1720s, it also
became home to one Stephen Gray.

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Stephen Gray had been a successful
silk dyer from Canterbury.

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He was used to seeing
electric sparks leap from the silk

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and they fascinated him.

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Unfortunately, a crippling accident
ended his career

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and left him destitute.

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But then he was offered
a new life here at Charterhouse

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and with it the time to perform
his own electrical experiments.

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Here at Charterhouse, possibly in
this very room, the Great Chamber,

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Stephen Gray built a wooden frame

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and from the top beam he suspended
two swings using silk rope.

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He also had a device like this,
a Hauksbee machine

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for generating static electricity.

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Now, with a large audience
in attendance,

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he got one of the orphan boys
who lived here at Charterhouse

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to lie across the two swings.

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Gray placed some gold leaf
in front of him.

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He then generated electricity

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and charged the boy
through a connecting rod.

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Gold leaf, even feathers,
leapt to the boy's fingers.

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Some of the audience
claimed they could even see sparks

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flying out from his fingertips.
Show business indeed.

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But to the curious
and inquiring mind of Stephen Gray,

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this said something else as well -

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electricity could move,

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from the machine to the boy's body,
through to his hands.

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But the silk rope stopped it dead.

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It meant the mysterious
electrical fluid

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could flow through some things...

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..but not through others.

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It led Gray to divide the world into
two different kinds of substances.

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He called them
insulators and conductors.

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Insulators held
electric charge within them

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and wouldn't let it move,
like the silk or hair,

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glass and resin.

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Whereas conductors allowed
electricity to flow through them,

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like the boy or metals.

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It's a distinction
which is still crucial even today.

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Just think of these electric pylons.

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They work on the same principle
that Gray deduced

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nearly 300 years ago.

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The wires are conductors.

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The glass and ceramic objects

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between the wire and the metal
of the pylon are insulators

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that stop the electricity
leaking from the wires

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into the pylon
and down to the earth.

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They're just like the silk ropes
in Gray's experiment.

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Back in the 1730s,

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Gray's experiment
may have astounded all who saw it,

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but it had a frustrating drawback.

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Try as he might, Gray
couldn't contain the electricity
he was generating for long.

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It leapt from the machine
to the boy and was quickly gone.

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The next step in our story came

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when we learnt
how to store electricity.

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But that would take place
not in Britain,

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but across the Channel
in mainland Europe.

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Across the Channel,
electricians were just as busy

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as their British counterparts and
one centre for electrical research

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was here in Leiden, Holland.

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And it was here that a professor
came up with an invention

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that many still regard as the most
significant of the 18th century,

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one that in some form or another
can still be found

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in almost every
electrical device today.

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That professor
was Pieter van Musschenbroek.

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Unlike Hauksbee and Gray,

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Musschenbroek
was born into academia.

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But ironically enough,
his breakthrough

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came not because
of his rigorous science,

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but because
of a simple human mistake.

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He was trying to find a way
to store electrical charge,

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ready for his demonstrations.
And you can almost hear

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his train of thought
as he tries to figure this out.

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If electricity is a fluid
that flows, a bit like water,

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then maybe you can store it in the
same way that you can store water.

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So Musschenbroek
went to his laboratory

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to try to make a device
to store electricity.

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Musschenbroek started
to think literally.

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He took a glass jar
and poured in some water.

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He then placed inside it
a length of conducting wire...

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..which was connected at the top
to a Hauksbee electric machine.

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'Then he put the jar on an insulator
to help keep the charge in the jar.'

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He then tried to pour
the electricity into the jar

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produced by the machine via the wire

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down through into the water.

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'But whatever he tried, the charge
just wouldn't stay in the jar.

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'Then one day, by accident,

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'he forgot to put the jar
on the insulator,

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'but charged it instead
while it was still in his hand.'

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Finally, holding the jar
with one hand,

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he touched the top with the other

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and received
such a powerful electric shock,

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he was almost thrown to the ground.

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He writes, "It's a new
but terrible experiment

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"which I advise you never to try.
Nor would I, who've experienced it

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"and survived by the grace of God
do it again

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"for all the kingdom of France."

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So I'm going to heed his advice,
not touch the top,

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and instead see if I can get
a spark off of it.

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The sheer power of the electricity
which flew from the jar

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was greater than any seen before.

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And even more surprisingly,

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the jar could store that electricity
for hours, even days.

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So in honour of the city where
Musschenbroek made his discovery,

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they called it the Leiden jar.

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And its fame
swept across the world.

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And very rapidly, from 1745
through the rest of the 1740s,

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the news of this - it's called
the Leiden jar - goes global.

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It spreads from Japan in East Asia

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to Philadelphia in eastern America.

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It became one of the first quick,
globalised, scientific news items.

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But although the Leiden jar became
a global electrical phenomenon,

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no-one had the slightest
idea how it worked.

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You have a jar of electric fluid,

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and it turns out that you get
a bigger shock from the jar

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if you allow the electric fluid
to drain away to the earth.

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Why is the shock bigger
if the jar's leaking?

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Why isn't the shock bigger if you
make sure all the electric fluid

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stays inside the jar?

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That was how mid-18th century
electrical philosophers

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were faced with this challenge.

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Electricity was without doubt
a fantastical wonder.

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It could shock and spark.

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It could now be stored
and moved around.

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Yet what electricity was,
how it worked,

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and why it did all these things

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was nothing less
than a complete mystery.

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Within 10 years,
a new breakthrough was to come

00:20:25.320 --> 00:20:28.120
from an unexpected quarter,

00:20:28.120 --> 00:20:31.840
From a man politically
and philosophically at war

00:20:31.840 --> 00:20:34.760
with the London establishment.

00:20:34.760 --> 00:20:38.600
And even more shockingly
for the British electrical elite,

00:20:38.600 --> 00:20:42.320
that man was merely a colonial.

00:20:42.320 --> 00:20:43.920
An American.

00:20:47.240 --> 00:20:49.360
This painting of Benjamin Franklin

00:20:49.360 --> 00:20:51.880
hangs here at the
Royal Society in London.

00:20:53.480 --> 00:20:57.960
Franklin was a passionate supporter
of American emancipation

00:20:57.960 --> 00:21:00.800
and saw the pursuit
of rational science,

00:21:00.800 --> 00:21:03.120
and particularly electricity,

00:21:03.120 --> 00:21:06.800
as a way of rolling back ignorance,
false idols

00:21:06.800 --> 00:21:13.080
and ultimately his intellectually
elitist colonial masters.

00:21:13.080 --> 00:21:19.000
And this is mixed with a profoundly
egalitarian democratic idea

00:21:19.000 --> 00:21:21.360
that Franklin and his allies have,

00:21:21.360 --> 00:21:25.000
which is this is
a phenomenon open to everyone.

00:21:25.000 --> 00:21:28.600
Here's something that the elite
doesn't really understand

00:21:28.600 --> 00:21:31.560
and we might be able
to understand it.

00:21:31.560 --> 00:21:34.720
Here's something that the elite
can't really control

00:21:34.720 --> 00:21:37.280
but we might be able to control.

00:21:37.280 --> 00:21:42.560
And here's something above all which
is the source of superstition.

00:21:42.560 --> 00:21:45.160
And we, rational, egalitarian,

00:21:45.160 --> 00:21:48.680
potentially democratic,
intellectuals,

00:21:48.680 --> 00:21:51.960
we will be able to reason it out,

00:21:51.960 --> 00:21:56.000
without appearing to be
the slaves of magic or mystery.

00:21:57.280 --> 00:22:01.200
So Franklin decided to use
the power of reason

00:22:01.200 --> 00:22:03.360
to rationally explain what many

00:22:03.360 --> 00:22:05.880
considered a magical phenomenon...

00:22:05.880 --> 00:22:07.120
Lightning.

00:22:07.120 --> 00:22:11.760
THUNDER BOOMS

00:22:11.760 --> 00:22:15.800
This is probably one of the most
famous scientific images

00:22:15.800 --> 00:22:17.280
of the 18th century.

00:22:17.280 --> 00:22:20.800
It shows Benjamin Franklin,
the heroic scientist,

00:22:20.800 --> 00:22:23.560
flying a kite in a storm,

00:22:23.560 --> 00:22:27.160
proving that lightning
is electrical.

00:22:27.160 --> 00:22:31.200
But although Franklin
proposed this experiment,

00:22:31.200 --> 00:22:33.640
he almost certainly
never performed it.

00:22:35.640 --> 00:22:39.920
Much more likely is that
his most significant experiment

00:22:39.920 --> 00:22:43.600
was another one which he proposed
but didn't even conduct.

00:22:43.600 --> 00:22:47.400
In fact, it didn't
even happen in America.

00:22:47.400 --> 00:22:50.320
It took place here in a small
village north of Paris

00:22:50.320 --> 00:22:52.160
called Marly La Ville.

00:22:55.320 --> 00:23:00.960
The French adored Franklin,
especially his
anti-British politics,

00:23:00.960 --> 00:23:03.680
and they took it upon themselves
to perform

00:23:03.680 --> 00:23:06.640
his other lightning
experiments without him.

00:23:07.640 --> 00:23:12.440
I've come to the very spot
where that experiment took place.

00:23:19.520 --> 00:23:23.160
In May 1752, George Louis Leclerc,

00:23:23.160 --> 00:23:27.000
known across France
as the Compte de Buffon,

00:23:27.000 --> 00:23:30.480
and his friend
Thomas Francois Dalibard,

00:23:30.480 --> 00:23:35.240
erected a 40-ft metal pole,
more than twice as high as this one,

00:23:35.240 --> 00:23:38.320
held in place
by three wooden staves,

00:23:38.320 --> 00:23:41.880
just outside Dalibard's house
here in the Marly La Ville.

00:23:41.880 --> 00:23:47.040
The metal pole rested at the bottom
inside an empty wine bottle.

00:23:50.840 --> 00:23:54.560
Franklin's big idea had been
that the long pole

00:23:54.560 --> 00:23:58.120
would capture the lightning,
pass it down the metal rod

00:23:58.120 --> 00:24:01.160
and store it in
the wine bottle at the base

00:24:01.160 --> 00:24:03.320
which worked as a Leiden jar.

00:24:03.320 --> 00:24:08.200
Then, he could confirm
what lightning actually was.

00:24:08.200 --> 00:24:12.120
All his French followers
had to do was wait for a storm.

00:24:17.040 --> 00:24:21.720
And then on May 23rd,
the heavens opened.

00:24:21.720 --> 00:24:23.880
THUNDER

00:24:23.880 --> 00:24:26.560
At 12.20, a loud
thunderclap was heard

00:24:26.560 --> 00:24:29.120
as lightning hit
the top of the pole.

00:24:31.080 --> 00:24:33.480
An assistant ran to the bottle,

00:24:33.480 --> 00:24:36.680
a spark leapt across

00:24:36.680 --> 00:24:39.240
between the metal and his finger
with a loud crack

00:24:39.240 --> 00:24:42.920
and a sulphurous smell,
burning his hand.

00:24:42.920 --> 00:24:47.600
The spark revealed lightning
for what it really was.

00:24:47.600 --> 00:24:51.880
It was the same as the electricity
made by man.

00:24:55.280 --> 00:24:58.920
It is hard to overestimate
the significance of this moment.

00:24:58.920 --> 00:25:03.480
Nature had been mastered, not only
that but the wrath of God itself

00:25:03.480 --> 00:25:06.920
had been brought
under the control of mankind.

00:25:06.920 --> 00:25:09.400
It was a kind of heresy.

00:25:09.400 --> 00:25:14.280
Franklin's experiment was very
important because it showed that

00:25:14.280 --> 00:25:18.920
lightning storms produce
or are produced by electricity

00:25:18.920 --> 00:25:22.880
and that you can bring
this electricity down,

00:25:22.880 --> 00:25:24.840
that electricity
is a force of nature

00:25:24.840 --> 00:25:26.920
that's waiting out there
to be tapped.

00:25:29.640 --> 00:25:34.640
Next, Franklin turned his rational
mind to another question.

00:25:34.640 --> 00:25:40.360
Why the Leiden jar made the biggest
sparks when it was held in the hand?

00:25:40.360 --> 00:25:44.520
Why didn't all the electricity
just drain away?

00:25:44.520 --> 00:25:49.320
In drawing on his experience
as a successful businessman,

00:25:49.320 --> 00:25:52.640
he saw something no-one else had.

00:25:52.640 --> 00:25:55.680
That like money in a bank,

00:25:55.680 --> 00:26:00.440
electricity can be in credit,
what he called positive,

00:26:00.440 --> 00:26:03.720
or debit, negative.

00:26:05.480 --> 00:26:09.520
For him, the problem of the Leiden
jar is one of accountancy.

00:26:09.520 --> 00:26:17.600
Franklin's idea was every body has
around an electrical atmosphere.

00:26:17.600 --> 00:26:22.600
And there is a natural amount
of electric fluid around each body.

00:26:22.600 --> 00:26:26.120
If there is too much,
we will call it positive.

00:26:26.120 --> 00:26:29.440
If there is too little,
we will call it negative.

00:26:29.440 --> 00:26:33.720
And nature is organised
so the positives and negatives

00:26:33.720 --> 00:26:35.920
always want to balance out,

00:26:35.920 --> 00:26:38.760
like an ideal American economy.

00:26:41.080 --> 00:26:46.200
Franklin's insight was that
electricity was actually just
positive charge

00:26:46.200 --> 00:26:50.120
flowing to cancel out
negative charge.

00:26:50.120 --> 00:26:52.880
And he believed this simple idea

00:26:52.880 --> 00:26:56.520
could solve the mystery
of the Leiden jar.

00:26:59.320 --> 00:27:01.480
As the jar is charged up,

00:27:01.480 --> 00:27:08.280
negative electrical charge is poured
down the wire and into the water.

00:27:08.280 --> 00:27:13.480
If the jar rests on an insulator,
a small amount builds up in the
water.

00:27:18.240 --> 00:27:23.120
But, if instead the jar is held by
someone as it is being charged,

00:27:23.120 --> 00:27:25.080
positive electric charge

00:27:25.080 --> 00:27:28.600
is sucked up through their
body from the ground

00:27:28.600 --> 00:27:30.400
to the outside of the jar,

00:27:30.400 --> 00:27:34.120
trying to cancel out
the negative charge inside.

00:27:36.160 --> 00:27:38.520
But the positive
and negative charges

00:27:38.520 --> 00:27:41.640
are stopped from cancelling out

00:27:41.640 --> 00:27:45.520
by the glass which
acts as an insulator.

00:27:45.520 --> 00:27:50.600
Instead, the charge just grows and
grows on both sides of the glass.

00:27:53.160 --> 00:27:56.760
Then, touching the top of the jar
with it the other hand,

00:27:56.760 --> 00:28:00.640
completes a circuit allowing
the negative charge on the inside

00:28:00.640 --> 00:28:05.520
to pass through the hand
to the positive on the outside,

00:28:05.520 --> 00:28:07.720
finally cancelling it out.

00:28:10.560 --> 00:28:16.400
The movement of this charge causes
a massive shock and often a spark.

00:28:22.120 --> 00:28:27.200
The modern equivalent of the Leiden
jar is this - the capacitor.

00:28:27.200 --> 00:28:30.920
It is one of the most
ubiquitous of electronic components.

00:28:30.920 --> 00:28:32.720
It is found everywhere.

00:28:32.720 --> 00:28:37.240
There are a number of smaller ones
scattered around on this circuit
board from a computer.

00:28:37.240 --> 00:28:40.800
They help smooth out
electrical surges,

00:28:40.800 --> 00:28:43.360
protecting sensitive components,

00:28:43.360 --> 00:28:46.400
even in the most modern
electric circuit.

00:28:57.000 --> 00:29:00.160
Solving the mystery
of the Leiden jar

00:29:00.160 --> 00:29:04.160
and recognising lightning as merely
a kind of electricity

00:29:04.160 --> 00:29:06.840
were two great successes
for Franklin

00:29:06.840 --> 00:29:09.440
and the new Enlightenment movement.

00:29:11.520 --> 00:29:14.400
But the forces of trade
and commerce,

00:29:14.400 --> 00:29:17.080
which helped fuel the Enlightenment,

00:29:17.080 --> 00:29:19.320
were about to throw up a new

00:29:19.320 --> 00:29:23.360
and even more perplexing
electrical mystery.

00:29:23.360 --> 00:29:26.920
A completely new
kind of electricity.

00:29:31.920 --> 00:29:33.920
This is the English Channel.

00:29:33.920 --> 00:29:36.000
By the 17th and 18th centuries,

00:29:36.000 --> 00:29:40.280
a good fraction of the world's
wealth flowed up this
stretch of water

00:29:40.280 --> 00:29:43.240
from all corners
of the British Empire

00:29:43.240 --> 00:29:45.680
and beyond, on its way to London.

00:29:45.680 --> 00:29:48.640
Spices from India,
sugar from the Caribbean,

00:29:48.640 --> 00:29:51.800
wheat from America, tea from China.

00:29:51.800 --> 00:29:54.640
But, of course,
it wasn't just commerce.

00:29:58.640 --> 00:30:00.840
New plants and animal specimens

00:30:00.840 --> 00:30:04.320
from all over the world
came flooding into London,

00:30:04.320 --> 00:30:08.680
including one that particularly
fascinated the electricians.

00:30:11.480 --> 00:30:16.720
Called the torpedo fish, it had been
the stuff of fishermen's tales.

00:30:16.720 --> 00:30:22.120
Its sting, it was said, was capable
of knocking a grown man down.

00:30:22.120 --> 00:30:26.040
But as the electricians started
to investigate the sting,

00:30:26.040 --> 00:30:30.160
they realised it felt strangely
similar to a shock

00:30:30.160 --> 00:30:31.680
from a Leiden jar.

00:30:34.240 --> 00:30:38.280
Could its sting actually
be an electric shock?

00:30:43.400 --> 00:30:48.160
At first, many people dismissed
the torpedo fish's shock as occult.

00:30:48.160 --> 00:30:51.760
Some said it was probably
just the fish biting.

00:30:51.760 --> 00:30:55.280
Others that it could not be a shock
because, without a spark,

00:30:55.280 --> 00:30:57.040
it just wasn't electricity.

00:30:57.040 --> 00:30:59.440
But, for most,
it was a very strange

00:30:59.440 --> 00:31:01.640
and inexplicable new mystery.

00:31:01.640 --> 00:31:03.320
It would take one of the oddest

00:31:03.320 --> 00:31:06.160
yet most brilliant
characters in British science

00:31:06.160 --> 00:31:09.520
to begin to unlock
the secrets of the torpedo fish.

00:31:14.760 --> 00:31:18.360
This is the only picture
in existence

00:31:18.360 --> 00:31:23.240
of the pathologically shy
but exceptional Henry Cavendish.

00:31:23.240 --> 00:31:27.960
This one only exists because
an artist sketched his coat

00:31:27.960 --> 00:31:32.040
as it hung on a peg, then filled
in the face from memory.

00:31:35.880 --> 00:31:38.320
His family were fantastically rich.

00:31:38.320 --> 00:31:40.120
They were the Devonshires

00:31:40.120 --> 00:31:44.640
who still own Chatsworth House
in Derbyshire.

00:31:44.640 --> 00:31:47.040
Henry Cavendish decided
to turn his back

00:31:47.040 --> 00:31:49.040
on his family's wealth and status

00:31:49.040 --> 00:31:53.160
to live in London
near his beloved Royal Society

00:31:53.160 --> 00:31:58.960
where he could quietly pursue his
passion for experimental science.

00:31:58.960 --> 00:32:04.080
When he heard about the electric
torpedo fish, he was intrigued.

00:32:04.080 --> 00:32:05.840
A friend wrote to him...

00:32:05.840 --> 00:32:10.240
"On this, my first experience
of the effect of the torpedo,

00:32:10.240 --> 00:32:14.640
"I exclaimed that this is
certainly electricity.

00:32:14.640 --> 00:32:16.760
"But how?"

00:32:16.760 --> 00:32:21.360
And to work out how a living thing
could produce electricity,

00:32:21.360 --> 00:32:27.000
he decided to make his own
artificial fish.

00:32:28.720 --> 00:32:30.200
These are his plans.

00:32:30.200 --> 00:32:35.880
Two Leiden jars shaped like the
fish which were buried under sand.

00:32:35.880 --> 00:32:41.240
When the sand was touched, they
discharged, giving a nasty shock.

00:32:41.240 --> 00:32:46.960
His model helped convince him that
the real torpedo fish was electric.

00:32:46.960 --> 00:32:50.880
But it still left him with
a nagging problem.

00:32:52.080 --> 00:32:56.160
Although both the real fish
and Cavendish's artificial one

00:32:56.160 --> 00:32:58.400
gave powerful electric shocks,

00:32:58.400 --> 00:33:02.240
the real fish never sparked.

00:33:02.240 --> 00:33:04.360
Cavendish was perplexed.

00:33:04.360 --> 00:33:07.200
How could it be the same
kind of electricity

00:33:07.200 --> 00:33:10.360
if they didn't both do the same
kinds of things?

00:33:12.720 --> 00:33:17.200
Cavendish spent the winter
of 1773 in his laboratory

00:33:17.200 --> 00:33:19.920
trying to come up with an answer.

00:33:19.920 --> 00:33:22.760
In the spring, he had a brainwave.

00:33:24.240 --> 00:33:27.960
Cavendish's ingenious answer was
to point out a subtle distinction

00:33:27.960 --> 00:33:32.640
between the amount
of electricity and its intensity.

00:33:32.640 --> 00:33:36.520
The real fish produced the same
kind of electricity.

00:33:36.520 --> 00:33:39.720
It is just that it was less intense.

00:33:39.720 --> 00:33:43.320
For a physicist like me,
this marks a crucial turning point.

00:33:43.320 --> 00:33:49.200
But it is the moment when two
genuinely innovative scientific
ideas first crop up.

00:33:49.200 --> 00:33:53.280
What Cavendish refers
to as the amount of electricity,

00:33:53.280 --> 00:33:56.280
we now call "electric charge".

00:33:56.280 --> 00:33:59.000
His intensity is what we call

00:33:59.000 --> 00:34:02.720
the potential difference
or "voltage".

00:34:05.360 --> 00:34:09.880
So the Leiden jar's shock was
high-voltage but low charge

00:34:09.880 --> 00:34:15.639
whereas the fish was low voltage
and high charge.

00:34:15.639 --> 00:34:18.960
It's possible
to actually measure that.

00:34:21.719 --> 00:34:25.120
Hiding at the bottom
of this tank under the sand

00:34:25.120 --> 00:34:28.719
is the Torpedo marmorata
and it's an electric ray.

00:34:28.719 --> 00:34:33.199
You can just see its eyes
protruding from the sand.

00:34:33.199 --> 00:34:35.520
This is a fully grown female

00:34:35.520 --> 00:34:37.880
and I am going to try and measure

00:34:37.880 --> 00:34:41.239
the electricity it gives off
with this bait.

00:34:41.239 --> 00:34:43.960
I have a fish connected to a
metal rod and hooked up

00:34:43.960 --> 00:34:45.440
to an oscilloscope

00:34:45.440 --> 00:34:49.120
to see if I can measure the voltage
as it catches its prey.

00:34:49.120 --> 00:34:51.159
Here goes!

00:35:03.720 --> 00:35:04.960
Oh! There's one!

00:35:10.800 --> 00:35:12.080
There's another one.

00:35:12.080 --> 00:35:15.480
The fish gave
a shock of about 240 volts,

00:35:15.480 --> 00:35:20.680
the same as mains electricity,
but still roughly 10 times less

00:35:20.680 --> 00:35:23.640
than the Leiden jar.

00:35:23.640 --> 00:35:26.080
That would have given me
quite a nasty shock

00:35:26.080 --> 00:35:29.240
and I can only try and imagine
what it must have been like

00:35:29.240 --> 00:35:32.320
for scientists in the 18th century
to witness this.

00:35:32.320 --> 00:35:36.920
An animal, a fish,
producing its own electricity.

00:35:39.680 --> 00:35:43.480
Cavendish had shown that the
torpedo fish made electricity

00:35:43.480 --> 00:35:46.960
but he didn't know if it was the
same kind of electricity

00:35:46.960 --> 00:35:49.840
as that made from
an electrical machine.

00:35:51.360 --> 00:35:54.880
Is the electrical shock
that a torpedo produces

00:35:54.880 --> 00:35:59.200
the same as produced
by an electrical machine?

00:35:59.200 --> 00:36:00.960
Or are there two kinds?

00:36:00.960 --> 00:36:05.000
A kind generated artificially or is
there a kind of animal electricity

00:36:05.000 --> 00:36:08.360
that only exists in living bodies?

00:36:08.360 --> 00:36:12.600
This was a huge debate that divided
opinion for several decades.

00:36:16.880 --> 00:36:21.600
Out of that bitter debate
came a new discovery.

00:36:21.600 --> 00:36:26.720
The discovery that electricity
needn't be a brief shock or spark.

00:36:26.720 --> 00:36:29.080
It could actually be continuous.

00:36:29.080 --> 00:36:32.960
And the generation
of continuous electricity

00:36:32.960 --> 00:36:35.760
would ultimately propel us
into our modern age.

00:36:48.480 --> 00:36:52.560
But the next step in the story
of electricity would come about

00:36:52.560 --> 00:36:56.640
because of a fierce personal
and professional rivalry

00:36:56.640 --> 00:36:59.080
between two Italian academics.

00:37:03.720 --> 00:37:08.480
BELL RINGS

00:37:14.640 --> 00:37:19.400
This is Bologna University,
one of the oldest in Europe.

00:37:19.400 --> 00:37:21.000
In the late 18th century,

00:37:21.000 --> 00:37:23.840
the city of Bologna was
ruled from papal Rome

00:37:23.840 --> 00:37:26.160
which meant that the
university was powerful

00:37:26.160 --> 00:37:27.960
but conservative in its thinking.

00:37:30.720 --> 00:37:34.480
It was steeped
in traditional Christianity,

00:37:34.480 --> 00:37:37.120
one where got ruled
earth from heaven

00:37:37.120 --> 00:37:39.360
but that the way he ran the world

00:37:39.360 --> 00:37:42.520
was hidden from us mere mortals

00:37:42.520 --> 00:37:46.280
who were not meant
to understand him,

00:37:46.280 --> 00:37:48.200
only to serve him.

00:37:48.200 --> 00:37:51.840
One of the university's
brightest stars

00:37:51.840 --> 00:37:54.840
was the anatomist
Luigi Aloisio Galvani.

00:37:54.840 --> 00:37:57.120
But, in a neighbouring city,

00:37:57.120 --> 00:38:01.480
a rival electrician
was about to take Galvani to task.

00:38:11.240 --> 00:38:14.680
This is Pavia,
only 150 miles from Bologna,

00:38:14.680 --> 00:38:17.400
but by the end of the 18th century,

00:38:17.400 --> 00:38:19.840
worlds apart politically.

00:38:19.840 --> 00:38:22.640
It was part of the Austrian
empire which put it

00:38:22.640 --> 00:38:25.680
at the very heart
of the European Enlightenment.

00:38:25.680 --> 00:38:28.120
Liberal in its thinking,
politically radical

00:38:28.120 --> 00:38:32.040
and obsessed with the new
science of electricity.

00:38:32.040 --> 00:38:35.360
It was also home to
Alessandro Volta.

00:38:39.960 --> 00:38:43.960
Alessandro Volta couldn't have been
more unlike Galvani.

00:38:43.960 --> 00:38:48.840
From an old Lombardi family,
he was young, arrogant, charismatic,

00:38:48.840 --> 00:38:50.200
a real ladies' man,

00:38:50.200 --> 00:38:52.360
and he courted controversy.

00:38:52.360 --> 00:38:56.080
Unlike Galvani, he liked
to show off his experiments

00:38:56.080 --> 00:38:59.200
on an international stage
to any audience.

00:38:59.200 --> 00:39:05.640
Volta's ideas were unfettered
by Galvani's religious dogma.

00:39:05.640 --> 00:39:09.040
Like Benjamin Franklin
and the European Enlightenment,

00:39:09.040 --> 00:39:11.600
he believed in rationality -

00:39:11.600 --> 00:39:13.560
that scientific truth,

00:39:13.560 --> 00:39:17.800
like a Greek god,
would cast ignorance to the floor.

00:39:17.800 --> 00:39:22.240
Superstition was the enemy.
Reason was the future.

00:39:25.640 --> 00:39:28.880
Both men were
fascinated by electricity.

00:39:28.880 --> 00:39:33.560
Both brought their different ways
of seeing the world to bear on it.

00:39:45.200 --> 00:39:49.000
Galvani had been attracted to
the use of electricity

00:39:49.000 --> 00:39:50.760
in medical treatments.

00:39:50.760 --> 00:39:53.840
For instance, in 1759,
here in Bologna,

00:39:53.840 --> 00:39:58.440
electricity was used on
the muscles of a paralysed man.

00:39:58.440 --> 00:40:01.840
One report said,

00:40:01.840 --> 00:40:07.120
"It was a fine sight to see
the mastoid rotate the head,

00:40:07.120 --> 00:40:09.920
"the biceps bend the elbow.

00:40:09.920 --> 00:40:14.240
"In short, to see the force
and vitality of all the motions

00:40:14.240 --> 00:40:18.960
"occurring in every paralysed
muscle subjected to the stimulus."

00:40:27.680 --> 00:40:30.760
Galvani believed
these kinds of examples

00:40:30.760 --> 00:40:35.080
revealed that the body
worked using animal electricity,

00:40:35.080 --> 00:40:37.880
a fluid that flows from the brain,

00:40:37.880 --> 00:40:40.480
through the nerves,
into the muscles,

00:40:40.480 --> 00:40:42.600
where it's turned into motion.

00:40:43.720 --> 00:40:48.280
He devised a series of
grisly experiments to prove it.

00:41:03.240 --> 00:41:05.880
Now, he first prepared a frog.

00:41:05.880 --> 00:41:09.760
He writes, "The frog is skinned
and disembowelled.

00:41:09.760 --> 00:41:12.440
"Only their lower limbs
are left joined together,

00:41:12.440 --> 00:41:15.040
"containing just the crural nerves."

00:41:15.040 --> 00:41:17.520
I've left my frog mostly intact,

00:41:17.520 --> 00:41:21.120
but I've exposed the nerves
that connect to the frog's legs.

00:41:21.120 --> 00:41:25.520
Then he used Hauksbee's
electrical machine

00:41:25.520 --> 00:41:28.480
to generate electrostatic charge,

00:41:28.480 --> 00:41:32.040
that would accumulate and travel
along this arm

00:41:32.040 --> 00:41:35.080
and out through this copper wire.

00:41:35.080 --> 00:41:39.400
Then he connected
the charge-carrying wire to the frog

00:41:39.400 --> 00:41:42.800
and another to the nerve
just above the leg.

00:41:43.800 --> 00:41:46.160
Let's see what happens.

00:41:48.320 --> 00:41:52.720
Ooh! And the frogs leg twitches,
just as it makes contact.

00:41:52.720 --> 00:41:53.920
There we go!

00:41:55.480 --> 00:42:01.080
For Galvani, what was going
on there was that there's a strange,

00:42:01.080 --> 00:42:05.640
special kind of entity
in the animal muscle,

00:42:05.640 --> 00:42:07.680
which he calls animal electricity.

00:42:07.680 --> 00:42:12.720
It's not like any other electricity.
It's intrinsic to living beings.

00:42:15.400 --> 00:42:21.640
But for Volta, animal electricity
smacked of superstition and magic.

00:42:21.640 --> 00:42:26.160
It had no place in rational
and enlightened science.

00:42:28.640 --> 00:42:33.080
Volta saw the experiment completely
differently to Galvani.

00:42:33.080 --> 00:42:36.720
He believed it revealed
something totally new.

00:42:36.720 --> 00:42:39.520
For him, the legs weren't jumping
as a result

00:42:39.520 --> 00:42:42.440
of the release of animal electricity
from within them,

00:42:42.440 --> 00:42:46.080
but because of the artificial
electricity from outside.

00:42:46.080 --> 00:42:49.480
The legs were merely the indicator.

00:42:49.480 --> 00:42:54.520
They were only twitching
because of the electricity
from the Hauksbee machine.

00:42:57.000 --> 00:43:02.240
Back in Bologna, Galvani
reacted furiously to Volta's ideas.

00:43:02.240 --> 00:43:06.440
He believed Volta had crossed
a fundamental line -

00:43:06.440 --> 00:43:10.280
from electrical experiments
into God's realm,

00:43:10.280 --> 00:43:13.720
and that was tantamount to heresy.

00:43:13.720 --> 00:43:17.400
To have a kind of spirit
like electricity,

00:43:17.400 --> 00:43:19.760
to have that produced artificially

00:43:19.760 --> 00:43:22.160
and to say that spirit,
that living force,

00:43:22.160 --> 00:43:26.320
that agency was the same
as something produced by God,

00:43:26.320 --> 00:43:30.400
that God had put into a living
human body or a frog's body,

00:43:30.400 --> 00:43:32.600
that seemed sacrilegious to them,

00:43:32.600 --> 00:43:35.200
because it was eliminating
this boundary

00:43:35.200 --> 00:43:37.480
between God's realm of the divine

00:43:37.480 --> 00:43:40.600
and the mundane realm
of the material.

00:43:43.800 --> 00:43:47.320
Spurred on by his
religious indignation,

00:43:47.320 --> 00:43:50.880
Galvani announced a new series
of experimental results,

00:43:50.880 --> 00:43:53.520
which would prove Volta was wrong.

00:43:55.080 --> 00:44:00.920
During one of his experiments,
he hung his frogs on an iron wire

00:44:00.920 --> 00:44:04.400
and saw something
totally unexpected.

00:44:04.400 --> 00:44:09.960
If he connected copper wire to
the wire the frog was hanging from,

00:44:09.960 --> 00:44:13.120
and then touched the other end
of the copper to the nerve...

00:44:14.960 --> 00:44:19.320
..it seemed to him he could make
the frog's legs twitch

00:44:19.320 --> 00:44:21.560
without any electricity at all.

00:44:28.680 --> 00:44:34.440
Galvani came to the conclusion
that it must have been

00:44:34.440 --> 00:44:39.000
something inside the frogs,
even if dead,

00:44:39.000 --> 00:44:42.120
that continued for a while
after death

00:44:42.120 --> 00:44:44.760
to produce some kind of electricity.

00:44:44.760 --> 00:44:50.080
And the metal wires were somehow
releasing that electricity.

00:44:51.720 --> 00:44:53.600
Over the next months,

00:44:53.600 --> 00:44:58.240
Galvani's experiments focused on
isolating this animal electricity

00:44:58.240 --> 00:45:01.080
using combinations
of frog and metal,

00:45:01.080 --> 00:45:03.680
Leiden jars
and electrical machines.

00:45:05.160 --> 00:45:09.320
For Galvani, these experiments
were proof the electricity

00:45:09.320 --> 00:45:12.840
was originating
within the frog itself.

00:45:12.840 --> 00:45:17.640
The frog's muscles were Leiden jars,
storing up the electrical fluid

00:45:17.640 --> 00:45:20.120
and then releasing it in a burst.

00:45:20.120 --> 00:45:25.840
On 30th October, 1786,
he published his findings in a book,

00:45:25.840 --> 00:45:31.320
Animali Electricitate -
Of Animal Electricity.

00:45:32.880 --> 00:45:35.800
Galvani was so confident
of his ideas,

00:45:35.800 --> 00:45:38.880
he even sent a copy of his book
to Volta.

00:45:41.040 --> 00:45:46.520
But Volta just couldn't stomach
Galvani's idea
of animal electricity.

00:45:46.520 --> 00:45:50.880
He thought the electricity just
had to come from somewhere else.

00:45:52.000 --> 00:45:53.040
But where?

00:46:04.360 --> 00:46:07.760
In the 1790s, here at
the University of Pavia,

00:46:07.760 --> 00:46:12.080
almost certainly in this lecture
theatre, which still bears his name,

00:46:12.080 --> 00:46:16.160
Volta began his search
for the new source of electricity.

00:46:18.320 --> 00:46:21.600
His suspicions focused on the metals

00:46:21.600 --> 00:46:24.680
that Galvani had used
to make his frog's legs twitch.

00:46:24.680 --> 00:46:30.680
His curiosity had been piqued by
an odd phenomenon he come across -

00:46:30.680 --> 00:46:33.920
how combinations of metals tasted.

00:46:36.360 --> 00:46:40.400
He found that if he took
two different metal coins

00:46:40.400 --> 00:46:42.760
and placed them on the tip
of his tongue,

00:46:42.760 --> 00:46:46.120
and then placed a silver spoon
on top of both...

00:46:47.840 --> 00:46:50.600
..he got
a kind of tingling sensation,

00:46:50.600 --> 00:46:54.160
rather like the tingling you'd get
from the discharge of a Leiden jar.

00:46:54.160 --> 00:46:57.960
Volta concluded
he could taste the electricity

00:46:57.960 --> 00:47:04.520
and it must be coming from the
contact between the different metals
in the coins and spoon.

00:47:04.520 --> 00:47:07.280
His theory flew in the face
of Galvani's.

00:47:07.280 --> 00:47:11.880
The frog's leg twitched, not because
of its own animal electricity,

00:47:11.880 --> 00:47:16.440
but because it was reacting to
the electricity from the metals.

00:47:16.440 --> 00:47:21.960
But the electricity his coins
generated was incredibly weak.

00:47:21.960 --> 00:47:24.000
How could he make it stronger?

00:47:28.160 --> 00:47:32.720
Then an idea came to him as he
revisited the scientific papers

00:47:32.720 --> 00:47:37.040
from the great British scientist,
Henry Cavendish,

00:47:37.040 --> 00:47:41.800
and in particular, his famous work
on the electric torpedo fish.

00:47:44.720 --> 00:47:49.560
He went back and took a closer
look at the torpedo fish

00:47:49.560 --> 00:47:53.880
and in particular, the repeating
pattern of chambers in its back.

00:47:53.880 --> 00:47:56.640
He wondered whether
it was this repeating pattern

00:47:56.640 --> 00:47:59.760
that held the key to its powerful
electric shock.

00:48:02.080 --> 00:48:06.080
Perhaps each chamber
was like his coins and spoon,

00:48:06.080 --> 00:48:10.400
each generating a tiny
amount of electricity.

00:48:10.400 --> 00:48:13.360
And, perhaps,
the fish's powerful shock

00:48:13.360 --> 00:48:19.120
results from the pattern of chambers
repeating over and over again.

00:48:20.160 --> 00:48:26.080
With growing confidence in his new
ideas, Volta decided to fight back

00:48:26.080 --> 00:48:31.400
by building his own artificial
version of the torpedo fish.

00:48:31.400 --> 00:48:36.040
So, he copied the torpedo
fish by repeating its pattern,

00:48:36.040 --> 00:48:38.400
but using metal.

00:48:38.400 --> 00:48:42.800
Here's what he did -
he took a copper metal plate

00:48:42.800 --> 00:48:47.480
and then placed above it a piece
of card soaked in dilute acid.

00:48:47.480 --> 00:48:51.160
Then above that, he took
another metal and placed it on top.

00:48:51.160 --> 00:48:56.120
What he had here was exactly the
same thing as Galvani's two wires.

00:48:56.120 --> 00:49:00.560
But now Volta repeated the process.

00:49:00.560 --> 00:49:04.800
What he was doing here
was building a pile of metal.

00:49:04.800 --> 00:49:09.360
In fact, his invention became
known as the pile.

00:49:14.080 --> 00:49:17.720
But it's what it could do that was
the really incredible revelation.

00:49:17.720 --> 00:49:22.400
Volta tried his pile out
on himself by getting two wires

00:49:22.400 --> 00:49:24.960
and attaching them
to each end of the pile

00:49:24.960 --> 00:49:27.720
and bringing the other ends
to touch his tongue.

00:49:30.000 --> 00:49:33.120
He could actually taste
the electricity.

00:49:33.120 --> 00:49:37.800
This time, it was more powerful
than normal and it was constant.

00:49:41.800 --> 00:49:45.840
He'd created the first battery.

00:49:45.840 --> 00:49:51.000
The machine was no longer an
electrical and mechanical machine,

00:49:51.000 --> 00:49:54.720
it was just purely
an electrical machine.

00:49:54.720 --> 00:49:58.640
So he proved that a machine
imitating the fish could work,

00:49:58.640 --> 00:50:03.400
that what he called
the metal or contact electricity

00:50:03.400 --> 00:50:05.840
of different metals could work,

00:50:05.840 --> 00:50:09.880
and that he regarded as his final,

00:50:09.880 --> 00:50:14.880
winning move in the controversy
with Galvani.

00:50:14.880 --> 00:50:19.680
What Volta's pile showed was that
you could develop all the phenomena

00:50:19.680 --> 00:50:24.560
of animal electricity
without any animals being present.

00:50:24.560 --> 00:50:30.280
So, from the Voltaic point of view,
it seemed as if Galvani was wrong,

00:50:30.280 --> 00:50:34.400
there's nothing special
about the electricity in animals.

00:50:34.400 --> 00:50:38.680
It's electricity
and it can be completely mimicked

00:50:38.680 --> 00:50:40.640
by this artificial pile.

00:50:43.120 --> 00:50:49.640
But the biggest surprise for Volta
was that the electricity
it generated was continuous.

00:50:49.640 --> 00:50:53.000
In fact, it poured out
like water in a stream.

00:50:53.000 --> 00:50:57.160
And just as in a stream, where
the measure of the amount of water

00:50:57.160 --> 00:51:00.720
flowing is called a current,
so the electricity flowing

00:51:00.720 --> 00:51:06.520
out of the pile became
known as an electrical current.

00:51:10.600 --> 00:51:13.920
200 years after Volta,

00:51:13.920 --> 00:51:17.200
we finally understand
what electricity actually is.

00:51:19.480 --> 00:51:23.880
The atoms in metals, like all atoms,
have electrically charged

00:51:23.880 --> 00:51:27.080
electrons surrounding a nucleus.

00:51:27.080 --> 00:51:30.560
But in metals, the atoms share
their outer electrons

00:51:30.560 --> 00:51:32.760
with each other in a unique way,

00:51:32.760 --> 00:51:36.160
which means they can move
from one atom to the next.

00:51:39.400 --> 00:51:43.760
If those electrons move in the same
direction at the same time,

00:51:43.760 --> 00:51:48.040
the cumulative effect
is a movement of electric charge.

00:51:50.040 --> 00:51:55.800
This flow of electrons
is what we call an electric current.

00:52:00.120 --> 00:52:03.920
Within weeks of Volta publishing
details of his pile,

00:52:03.920 --> 00:52:08.280
scientists were discovering
something incredible about
what it could do.

00:52:16.240 --> 00:52:20.240
Its effect on ordinary water
was completely unexpected.

00:52:20.240 --> 00:52:23.960
The constant stream of electric
charge into the water

00:52:23.960 --> 00:52:27.280
was ripping it up
into its constituent parts -

00:52:27.280 --> 00:52:30.640
the gases, oxygen and hydrogen.

00:52:30.640 --> 00:52:34.920
Electricity was heralding
the dawn of a new age.

00:52:34.920 --> 00:52:40.120
A new age where electricity
ceased being a mere curiosity

00:52:40.120 --> 00:52:44.680
and started being genuinely useful.

00:52:44.680 --> 00:52:47.360
With constant flowing
current electricity,

00:52:47.360 --> 00:52:51.200
new chemical elements
could be isolated with ease.

00:52:51.200 --> 00:52:56.880
And this laid the foundations
for chemistry, physics
and modern industry.

00:52:59.560 --> 00:53:02.880
Volta's pile changed everything.

00:53:08.040 --> 00:53:11.600
The pile made Volta
an international celebrity,

00:53:11.600 --> 00:53:15.840
feted by the powerful and the rich.

00:53:15.840 --> 00:53:17.080
In recognition,

00:53:17.080 --> 00:53:21.800
a fundamental measure of electricity
was named in his honour.

00:53:21.800 --> 00:53:22.840
The volt.

00:53:26.920 --> 00:53:32.040
But his scientific adversary
didn't fare quite so well.

00:53:32.040 --> 00:53:38.800
Luigi Aloisio Galvani
died on 4th December 1798,

00:53:38.800 --> 00:53:41.440
depressed and in poverty.

00:53:41.440 --> 00:53:45.160
For me, it's not
the invention of the battery

00:53:45.160 --> 00:53:49.600
that marked the crucial turning
point in the story of electricity,

00:53:49.600 --> 00:53:52.040
it's what happened next.

00:54:01.800 --> 00:54:05.200
It took place
in London's Royal Institution.

00:54:05.200 --> 00:54:09.080
It was the moment that marked
the end of one era

00:54:09.080 --> 00:54:11.120
and the beginning of another.

00:54:15.040 --> 00:54:17.720
It was overseen by Humphry Davy,

00:54:17.720 --> 00:54:21.280
the first of a new generation
of electricians.

00:54:21.280 --> 00:54:27.680
Young, confident and fascinated by
the possibilities of continuous
electrical current.

00:54:27.680 --> 00:54:34.080
So, in 1808, he built
the world's largest battery.

00:54:34.080 --> 00:54:37.680
It filled an entire room
underneath the Royal Institution.

00:54:37.680 --> 00:54:43.960
It had over 800 individual
voltaic piles attached together.

00:54:43.960 --> 00:54:48.760
It must have hissed
and breathed sulphurous fumes.

00:54:51.280 --> 00:54:58.320
In a darkened room,
lit by centuries-old technology,
candles and oil lamps,

00:54:58.320 --> 00:55:02.800
Davy connected his battery
to two carbon filaments

00:55:02.800 --> 00:55:05.440
and brought the tips together.

00:55:05.440 --> 00:55:08.200
The continuous flow of electricity
from the battery

00:55:08.200 --> 00:55:11.320
through the filaments
leapt across the gap,

00:55:11.320 --> 00:55:16.840
giving rise to a constant
and blindingly bright spark.

00:55:22.520 --> 00:55:27.040
Out of the darkness came the light.

00:55:38.840 --> 00:55:43.840
Davy's arc light truly symbolises
the end of one era

00:55:43.840 --> 00:55:46.680
and the beginning of our era.

00:55:46.680 --> 00:55:48.320
The era of electricity.

00:55:57.680 --> 00:56:04.280
But there's a truly grisly
coda to this story.

00:56:04.280 --> 00:56:08.280
In 1803, Galvani's nephew,
one Giovanni Aldini,

00:56:08.280 --> 00:56:12.920
came to London with
a terrifying new experiment.

00:56:12.920 --> 00:56:15.840
A convicted murderer
called George Forster

00:56:15.840 --> 00:56:18.120
had just been hanged in Newgate.

00:56:18.120 --> 00:56:21.040
When the body was cut down
from the gallows,

00:56:21.040 --> 00:56:23.680
it was brought directly
to the lecture theatre,

00:56:23.680 --> 00:56:27.040
where Aldini
started his macabre work.

00:56:30.240 --> 00:56:32.040
Using a voltaic pile,

00:56:32.040 --> 00:56:37.520
he began to apply an electric
current to the dead man's body.

00:56:37.520 --> 00:56:43.160
Then Aldini put one electrical
conductor in the dead man's anus

00:56:43.160 --> 00:56:45.920
and the other
at the top of his spine.

00:56:45.920 --> 00:56:50.160
Forster's limp, dead body
sat bolt upright

00:56:50.160 --> 00:56:52.960
and his spine arched and twisted.

00:56:52.960 --> 00:56:55.840
For a moment, it seemed as though
the dead body

00:56:55.840 --> 00:56:58.680
had been brought back to life.

00:57:00.240 --> 00:57:06.240
It appeared as though electricity
might have the power
of resurrection.

00:57:06.240 --> 00:57:11.560
And this made a profound impact on
a young writer called Mary Shelley.

00:57:17.040 --> 00:57:22.400
Mary Shelley wrote one of the most
powerful and enduring stories ever.

00:57:22.400 --> 00:57:24.680
Based partly here on Lake Como,

00:57:24.680 --> 00:57:27.640
Frankenstein tells
the story of a scientist,

00:57:27.640 --> 00:57:30.120
a Galvanist probably
based on Aldini,

00:57:30.120 --> 00:57:34.160
who brings a monster
to life using electricity.

00:57:34.160 --> 00:57:40.040
And then, disgusted by his own
arrogance, he abandons his creation.

00:57:40.040 --> 00:57:45.640
Just like Davy's arc lamp,
this book symbolises changing times.

00:57:45.640 --> 00:57:49.240
The end of the era of miracles
and romance

00:57:49.240 --> 00:57:54.440
and the beginning of the era of
rationality, industry and science.

00:58:06.240 --> 00:58:10.400
And it's that new age
we explore in the next programme,

00:58:10.400 --> 00:58:12.880
because at the start of
the 19th century,

00:58:12.880 --> 00:58:17.680
scientists realised electricity
was intimately connected

00:58:17.680 --> 00:58:21.320
with another of nature's
mysterious forces...

00:58:21.320 --> 00:58:22.440
magnetism.

00:58:23.480 --> 00:58:27.600
And that realisation would
completely transform our world.

00:58:29.640 --> 00:58:32.920
To find out more about
the story of electricity

00:58:32.920 --> 00:58:35.840
and to put your power knowledge
to the test,

00:58:35.840 --> 00:58:39.640
try the Open University's
interactive energy game.

00:58:39.640 --> 00:58:41.240
Go to...

00:58:44.640 --> 00:58:47.080
..and follow links
to the Open University.

00:59:09.320 --> 00:59:12.360
Subtitles by Red Bee Media Ltd

00:59:12.360 --> 00:59:15.400
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