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00:08At the dawn of the 19th century, in a cellar in Mayfair, the most famous scientist of the time,
00:15Humphrey Davy, built an extraordinary piece of electrical equipment. Four meters wide,
00:22twice as long, and containing stinking stacks of acid and metal. It had been created to pump
00:29out more electricity than had ever been possible before. It was, in fact, the biggest battery
00:35the world had ever seen. And with it, Davy was about to propel us into a new age.
00:55That moment would take place at a lecture at the Royal Institution in front of hundreds of London's
01:02great and good. Filled with anticipation, they packed the seats, hoping to witness a new and
01:09exciting electrical wonder. But what they would see that night would be something truly unique,
01:16something they'd remember for the rest of their lives. Using just two simple carbon rods,
01:23Humphrey Davy was about to unleash the true potential of electricity.
01:35Electricity is one of nature's most awesome phenomena, and the most powerful manifestation of it
01:42we ever see is lightning.
01:47This is the story of how we first dreamed of controlling this primal force of nature,
01:53and how we would ultimately become its master.
01:58It's a 300-year tale of dazzling leaps of imagination and extraordinary experiments.
02:06Tens of thousands of volts passed across his body and through the end of a lamp that he was holding.
02:14It's a story of maverick geniuses who used electricity to light our cities,
02:20to communicate across the seas and through the air,
02:23to create modern industry, and to give us the digital revolution.
02:32But in this film, we'll tell the story of the very first scientists
02:37who started to unlock the mysteries of electricity.
02:43They studied its curious link to life, built strange and powerful instruments to create it,
02:50and even tamed lightning itself.
02:55It was these men who truly laid the foundations of the modern world.
03:01And it all started with a spark.
03:19Imagine our world without electricity.
03:24It will be dark, cold, and quiet.
03:30In many ways, it will be like the beginning of the 18th century,
03:35where our story begins.
03:42This is the Royal Society in London.
03:46In the early 1700s, after years in the wilderness,
03:51Isaac Newton finally took control of it,
03:54after the death of his arch-enemy, Robert Hooke.
04:00Newton brought in his own people to the key jobs,
04:03to help shore up his new position.
04:06The new head of demonstrations there was 35-year-old Francis Hawksby.
04:12Notes from the Royal Society in 1705
04:15reveal how hard Hawksby tried to stamp his personality on its weekly meetings,
04:21producing ever-more spectacular experiments to impress his masters.
04:31In November, he came up with this, a rotating glass sphere.
04:37He was able to remove the air from inside it using a new machine, the air pump.
04:43On his machine, a handle allowed him to spin the sphere.
04:50One by one, the candles in the room were put out.
04:56And Francis placed his hand against the sphere.
05:00The audience were about to see something amazing.
05:11Inside the glass sphere, a strange, ethereal light began to form,
05:17dancing around his hand,
05:19a light no-one had ever seen before.
05:24Oh, that's fantastic.
05:27I see a beautiful blue glow.
05:29It's just marking out the shape of my hands,
05:31but then going right round the ball.
05:34Oh, there's something alive in there.
05:40It's difficult to really understand
05:42why this dancing blue light meant so much.
05:47But we have to bear in mind that at the time,
05:50natural phenomena like this
05:52were seen to be the work of the Almighty.
05:55This was still a period when,
05:57even in Isaac Newton's theory,
05:59God was constantly intervening in the conduct of the world.
06:04And so it made sense for a lot of people
06:06to interpret natural phenomena as acts of God.
06:12So when a mere mortal meddled with God's work,
06:16it was almost beyond rational comprehension.
06:21Hawksby never realised the full significance of his experiment.
06:25He lost interest in his glowing sphere
06:27and spent the last few years of his life
06:29building ever more spectacular experiments
06:32for Isaac Newton to test his other theories.
06:35He never realised that he'd unwittingly started
06:38an electrical revolution.
06:46Before Hawksby, electricity had been merely a curiosity.
06:51The ancient Greeks rubbed amber,
06:54which they called electron, to get small shocks.
06:58And even Queen Elizabeth I
07:01marvelled at static electricity's power to lift feathers.
07:06But now Hawksby's machine
07:09could make electricity at the turn of a handle.
07:13And you could see it.
07:16And perhaps even more importantly,
07:19his invention coincided with the birth
07:22of a new movement sweeping across Europe
07:24called the Enlightenment.
07:28Enlightened intellectuals used reason to question the world.
07:32And their legacy was radical politics,
07:35iconoclastic art,
07:36and natural philosophy or science.
07:46But ironically, Hawksby's new machine
07:49wasn't immediately embraced
07:50by most of these intellectuals,
07:52but instead by conjurers and street magicians.
07:57And those with an interest in electricity
07:59called themselves electricians.
08:06One story tells of a dinner party
08:09attended by an Austrian count.
08:11The electrician had placed some feathers on the table
08:14and then charged up a glass rod
08:17with a silk handkerchief.
08:19He then astonished the guests
08:21by lifting up the feathers with the rod.
08:26He then went on to charge himself up
08:29using one of Hawksby's electrical machines
08:33and gave the guests electric shocks,
08:36presumably to squeals of delight.
08:39But for his piece de resistance,
08:41he placed a glass of cognac in the centre of the table,
08:45charged himself up again
08:46and lit it with a spark from the tip of his finger.
08:51APPLAUSE
08:53There was a trick called the electrical beatification,
08:56in which the victim sits on an insulated chair
09:00and above his head hangs a metal crown
09:04that doesn't quite touch his head.
09:07And then if the crown is electrified,
09:10then you get an electric discharge around the crown
09:14that looks exactly like a halo,
09:16which is why it's called the electric beatification.
09:23As England and the rest of Europe went electricity crazy,
09:27the spectacles grew bigger
09:29and the more curious electricians
09:31started to ask more profound questions.
09:35Not only how can we make our shows bigger and better,
09:38but how can we control this amazing power?
09:42And for some,
09:44can this incredible electrical fire
09:46do more than just entertain?
09:58One of the first early breakthroughs
10:00would never have happened
10:02had it not been for a terrible accident.
10:08This is Charterhouse in the centre of London.
10:12Over the past 400 years,
10:13it's been a charitable home
10:15for young orphans and elderly gentlemen.
10:17And sometime in the 1720s,
10:20it also became home to one Stephen Gray.
10:28Stephen Gray had been a successful silk dyer from Canterbury.
10:32He was used to seeing electric sparks leap from the silk
10:36and they fascinated him.
10:39Unfortunately, a crippling accident ended his career
10:42and left him destitute.
10:45But then he was offered a new life
10:47here at Charterhouse
10:48and with it,
10:50the time to perform
10:51his own electrical experiments.
10:59Here at Charterhouse,
11:01possibly in this very room,
11:03the great chamber,
11:04Stephen Gray built a wooden frame.
11:07From the top beam,
11:08he suspended two swings using silk rope.
11:14He also had a device like this,
11:16a Hawksby machine,
11:17for generating static electricity.
11:22Now, with a large audience and attendance,
11:25he got one of the orphan boys
11:27who lived here at Charterhouse
11:28to lie across the two swings.
11:33Gray placed some gold leaf in front of him.
11:49He then generated electricity
11:51and charged the boy through a connecting rod.
12:12Gold leaf, even feathers,
12:15leapt to the boy's fingers.
12:17Some of the audience claimed
12:18they could even see sparks flying out
12:20from his fingertips.
12:22Show business indeed.
12:28But to the curious and inquiring mind
12:31of Stephen Gray,
12:32this said something else as well.
12:35Electricity could move.
12:37From the machine to the boy's body
12:40through to his hands.
12:42But the silk rope stopped it dead.
12:47It meant the mysterious electrical fluid
12:51could flow through some things,
12:54but not through others.
13:04It led Gray to divide the world
13:07into two different kinds of substances.
13:10He called them insulators and conductors.
13:13Insulators held electric charge within them
13:16and wouldn't let it move,
13:18like the silk or hair, glass and resin,
13:23whereas conductors allowed electricity
13:25to flow through them,
13:27like the boy or metals.
13:30It's a distinction which is still crucial even today.
13:38Just think of these electric pylons.
13:43They work on the same principle
13:45that Gray deduced nearly 300 years ago.
13:51The wires are conductors.
13:54The glass and ceramic objects
13:56between the wire and the metal of the pylon
13:59are insulators that stop the electricity
14:02leaking from the wires
14:04into the pylon and down to the earth.
14:09They're just like the silk ropes
14:12in Gray's experiment.
14:17Back in the 1730s,
14:20Gray's experiment may have astounded
14:22all who saw it,
14:24but it had a frustrating drawback.
14:29Try as he might,
14:30Gray couldn't contain the electricity
14:33he was generating for long.
14:35It leapt from the machine
14:36to the boy
14:37and was quickly gone.
14:39The next step in our story
14:41came when we learnt
14:43how to store electricity,
14:45but that would take place
14:46not in Britain,
14:47but across the channel
14:48in mainland Europe.
15:05Across the channel,
15:07electricians were just as busy
15:08as their British counterparts,
15:10and one centre for electrical research
15:13was here in Leiden, Holland.
15:19And it was here
15:20that a professor
15:20came up with an invention
15:21that many still regard
15:23as the most significant
15:24of the 18th century,
15:26one that,
15:27in some form or another,
15:28can still be found
15:29in almost every electrical device today.
15:34That professor
15:35was Pieter van Muchenbroek.
15:38Unlike Hawksby and Gray,
15:40Muchenbroek
15:41was born into academia.
15:46But, ironically enough,
15:48his breakthrough
15:48came not because
15:50of his rigorous science,
15:51but because of a simple
15:53human mistake.
15:59He was trying to find a way
16:01to store electrical charge
16:03ready for his demonstrations,
16:05and you can almost hear
16:07his train of thought
16:08as he tries to figure this out.
16:11that if electricity
16:13is a fluid
16:13that flows
16:15a bit like water,
16:17then maybe you can store it
16:18in the same way
16:19that you can store water.
16:23So Muchenbroek
16:25went to his laboratory
16:26to try to make a device
16:28to store electricity.
16:31Muchenbroek
16:32started to think literally.
16:34He took a glass jar
16:36and poured in some water.
16:41He then placed inside it
16:43a length of conducting wire
16:47which was connected at the top
16:49to a Hawksby electric machine.
16:53Then he put the jar
16:55on an insulator
16:56to help keep the charge
16:58in the jar.
16:59He then tried
17:01to pour the electricity
17:03into the jar
17:04produced by the machine
17:06via the wire
17:07down through
17:08into the water.
17:10But whatever he tried
17:12the charge
17:13just wouldn't stay
17:15in the jar.
17:18Then one day
17:19by accident
17:20he forgot
17:21to put the jar
17:22on the insulator
17:23but charged it instead
17:25while it was still
17:26in his hand.
17:34Finally,
17:35holding the jar
17:36with one hand
17:36he touched the top
17:38with the other
17:38and received
17:39such a powerful
17:40electric shock
17:41he was almost
17:42thrown to the ground.
17:44He writes,
17:45it's a new
17:46but terrible experiment
17:48which I advise you
17:49never to try.
17:50Nor would I
17:51who've experienced it
17:53and survived
17:53by the grace of God
17:55do it again
17:56for all the kingdom
17:57of France.
17:58So I'm going to
17:59heed his advice
18:00not touch the top
18:02but instead
18:03see if I can get
18:03a spark
18:04off of it.
18:10The sheer power
18:12of the electricity
18:13which flew
18:14from the jar
18:15was greater
18:16than any
18:17seen before.
18:19And even more
18:21surprisingly
18:21the jar
18:22could store
18:23that electricity
18:24for hours
18:25even days.
18:30So in honour
18:32of the city
18:32where Mushenbrook
18:33made his discovery
18:34they called it
18:36the Leiden Jar
18:39and its fame
18:40swept across the world.
18:43And very rapidly
18:44from 1745
18:46through the rest
18:46of the 1740s
18:47the news of this
18:49it's called
18:49the Leiden Jar
18:50goes global.
18:52It spreads
18:53from Japan
18:54in East Asia
18:55to Philadelphia
18:57in Eastern America.
18:58It became
18:59one of the first
19:01quick
19:02globalised
19:03scientific
19:04news items.
19:07But although
19:08the Leiden Jar
19:09became a global
19:11electrical phenomenon
19:12no one
19:13had the slightest
19:15idea
19:15how it worked.
19:18You have a jar
19:19of electric fluid
19:20and it turns out
19:21that you get
19:22a bigger shock
19:23from the jar
19:24if you allow
19:25the electric fluid
19:26to drain away
19:28to the earth.
19:29Why is the shock
19:30bigger
19:31if the jar
19:32is leaking?
19:33Why isn't the shock
19:34bigger
19:35if you make sure
19:36that all the electric
19:37fluid stays inside
19:39the jar?
19:39That was how
19:40mid-18th century
19:41electrical philosophers
19:43were faced
19:43with this challenge.
19:48Electricity was
19:50without doubt
19:50a fantastical wonder.
19:52it could shock
19:54and spark
19:55it could now
19:57be stored
19:57and moved around
19:58yet what electricity
20:00was
20:01how it worked
20:03and why
20:04it did all these things
20:05was nothing less
20:07than a complete mystery.
20:21within ten years
20:23a new breakthrough
20:24was to come
20:25from an unexpected quarter
20:27from a man
20:28politically
20:29and philosophically
20:30at war
20:31with the London establishment
20:33and even more
20:35shockingly
20:35for the British
20:36electrical elite
20:37that man
20:39was merely
20:40a colonial
20:41an American.
20:46This painting
20:47of Benjamin Franklin
20:48hangs here
20:49at the Royal Society
20:50in London.
20:52Franklin
20:53was a passionate
20:55supporter
20:55of American
20:56emancipation
20:57and saw
20:58the pursuit
20:58of rational science
21:00and particularly
21:01electricity
21:02as a way
21:03of rolling
21:04back ignorance
21:05false idols
21:06and ultimately
21:07his intellectually
21:09elitist
21:10colonial masters.
21:12And this is mixed
21:14with
21:14a profoundly
21:16egalitarian
21:17democratic idea
21:18that Franklin
21:19and his allies
21:20have
21:20which is
21:21this is a phenomenon
21:22open to everyone.
21:24Here's something
21:25that the elite
21:26doesn't really understand
21:27and we might
21:29be able
21:29to understand
21:30it.
21:31Here's something
21:31that the elite
21:32can't really control
21:34but we might
21:35be able
21:35to control
21:36and here's
21:37something
21:38above all
21:39which is
21:40the source
21:40of superstition
21:41and we
21:43rational
21:45egalitarian
21:46potentially
21:46democratic
21:47intellectuals
21:48we will be
21:49able to
21:50reason it
21:51out
21:51without
21:51appearing
21:52to be
21:53the slaves
21:54of magic
21:54or mystery.
21:56So Franklin
21:57decided to
21:58use the
21:59power of
22:00reason
22:00to rationally
22:01explain
22:02what many
22:03considered
22:03a magical
22:04phenomenon
22:05lightning.
22:10This is probably
22:12one of the most
22:13famous scientific
22:14images of the
22:1518th century.
22:16It shows
22:17Benjamin Franklin
22:18the heroic
22:19scientist
22:20flying a kite
22:22in a storm
22:22proving
22:23that lightning
22:25is electrical.
22:27But although
22:27Franklin proposed
22:29this experiment
22:29he almost
22:30certainly
22:31never
22:32performed it.
22:35Much more
22:36likely
22:37is that his
22:38most significant
22:38experiment
22:39was another
22:40one
22:40which he
22:40proposed
22:41but didn't
22:42even conduct.
22:43In fact
22:43it didn't
22:44even happen
22:45in America.
22:46It took
22:46place here
22:47in a small
22:48village
22:48north of
22:49Paris
22:49called
22:50Marley-les-ville.
22:55The French
22:56adored
22:57Franklin
22:57especially
22:58his
22:59anti-British
22:59politics
23:00and they
23:01took it
23:01upon
23:01themselves
23:02to perform
23:03his other
23:03lightning
23:04experiments
23:04without him.
23:07I've come
23:08to the very
23:09spot
23:10where that
23:10experiment
23:11took place.
23:19in May
23:201752
23:21George
23:22Louis
23:23Leclerc
23:23known across
23:24France
23:24as the
23:25Comte de
23:25Buffon
23:26and his
23:27friend
23:27Thomas
23:27Francois
23:28Delibar
23:29erected
23:30a 40-foot
23:31metal pole
23:32more than
23:33twice as high
23:34as this
23:34one
23:34held in
23:36place by
23:36three wooden
23:37staves
23:37just outside
23:39Delibar's
23:39house
23:40here in
23:40Marley-le-ville.
23:41The metal pole
23:43rested at the
23:44bottom inside
23:45an empty
23:45wine bottle.
23:50Franklin's
23:51big idea
23:52had been that
23:53the long pole
23:53would capture
23:54the lightning,
23:55pass it down
23:56the metal rod
23:57and store it
23:58in the wine bottle
23:59at the base
24:00which worked
24:01as a
24:01Leiden jar.
24:03Then he could
24:04confirm what
24:05lightning actually
24:06was.
24:07All his French
24:09followers had to
24:09do was wait
24:11for a storm.
24:17And then on
24:18May 23rd
24:19the heavens
24:20opened.
24:22At 12.20
24:24a loud
24:25thunderclap
24:26was heard
24:26as lightning
24:27hit the top
24:28of the pole.
24:31An assistant
24:32ran to the
24:32bottle.
24:34A spark
24:35leapt across
24:36between the
24:36metal and his
24:37finger
24:37with a loud
24:38crack and
24:39a sulphurous
24:40smell
24:40burning his
24:41hand.
24:42The spark
24:44revealed lightning
24:45for what it
24:45really was.
24:47It was the
24:48same as the
24:49electricity
24:50made by man.
24:54It's hard
24:55to overestimate
24:56the significance
24:57of this moment.
24:58Nature had been
24:59mastered.
25:00Not only that
25:01but the wrath
25:02of God itself
25:03had been brought
25:03under the control
25:05of mankind.
25:06It was a kind
25:07of heresy.
25:10Franklin's
25:10experiment was
25:11very important
25:12because it showed
25:13that lightning
25:14storms produce
25:16or are produced
25:17by electricity
25:18and that you
25:19can bring this
25:20electricity down.
25:21That electricity
25:22is a force
25:23of nature
25:24that's waiting
25:25out there
25:25to be tapped.
25:29Next, Franklin
25:30turned his
25:31rational mind
25:32to another
25:33question.
25:34Why the
25:35Leidenjar
25:36made the
25:36bigger sparks
25:37when it was
25:38held in the
25:39hand?
25:40Why didn't
25:41all the
25:41electricity
25:41just drain
25:43away?
25:45And drawing
25:45on his
25:46experience
25:46as a
25:47successful
25:47businessman,
25:48he saw
25:49something
25:50no-one
25:50else had.
25:52that, like
25:53money in a
25:54bank,
25:55electricity
25:55can be in
25:57credit,
25:58what he
25:58called positive
25:59or debit
26:01negative.
26:03For him,
26:04the problem
26:05of the
26:05Leidenjar
26:06is a problem
26:06of accountancy.
26:08Franklin's
26:09idea was
26:10every body
26:12has around
26:14it an
26:14electrical
26:15atmosphere.
26:17And there's
26:18a natural
26:18amount of
26:19electric fluid
26:20around each
26:21body.
26:22If there's
26:23too much,
26:24we'll call it
26:24positive.
26:25If there's
26:26too little,
26:27we'll call it
26:28negative.
26:29And nature
26:30is organized,
26:31so the
26:31positives and
26:32the negatives
26:32always want to
26:33balance out,
26:34like an ideal
26:36American economy.
26:40Franklin's
26:41insight was
26:42that electricity
26:43was actually
26:44just positive
26:45charge flowing
26:47to cancel
26:48out negative
26:49charge.
26:50And he
26:50believed this
26:51simple idea
26:52could solve
26:53the mystery
26:54of the
26:54Leidenjar.
26:58As the
26:59jar is
27:00charged up,
27:01negative
27:02electrical
27:03charge is
27:04poured down
27:05the wire
27:05and into
27:06the water.
27:08If the
27:08jar rests
27:09on an
27:09insulator,
27:10a small
27:11amount
27:11builds up
27:12in the
27:12water.
27:17But if
27:18instead the
27:19jar is
27:19held by
27:20someone as
27:21it's being
27:21charged,
27:23positive
27:23electric
27:23charge is
27:24sucked up
27:25through their
27:26body from
27:27the ground
27:28to the
27:28outside of
27:29the jar,
27:30trying to
27:31cancel out
27:32the negative
27:32charge
27:33inside.
27:35but the
27:36positive
27:37and negative
27:37charges are
27:38stopped from
27:39cancelling out
27:40by the
27:40glass,
27:41which acts
27:42as an
27:42insulator.
27:44So instead,
27:45the charge
27:46just grows
27:47and grows
27:48on both
27:48sides of
27:49the glass.
27:53Then,
27:54touching the
27:54top of the
27:55jar with
27:55the other
27:56hand,
27:56completes a
27:57circuit,
27:58allowing the
27:59negative charge
28:00on the
28:00inside to
28:01pass through
28:02the hand
28:03to the
28:03positive
28:04on the
28:04outside,
28:05finally
28:06cancelling
28:07it out.
28:09The movement
28:11of this
28:11charge causes
28:12a massive
28:13shock and
28:14often a
28:15spark.
28:21The modern
28:22equivalent of
28:23the Leiden
28:23jar is
28:24this,
28:25the
28:26capacitor,
28:26and it's
28:27one of the
28:27most ubiquitous
28:28of electronic
28:29components.
28:30It's found
28:31everywhere.
28:32There are a
28:33number of
28:33smaller ones
28:34scattered around
28:34on this
28:35circuit board
28:36from a
28:36computer.
28:37They help
28:38smooth out
28:39electrical
28:40surges,
28:40protecting
28:41sensitive
28:42components,
28:43even in
28:44the most
28:44modern
28:44electric
28:45circuit.
28:57Solving the
28:58mystery of
28:59mystery of
28:59the Leiden
28:59jar and
29:00recognising
29:01lightning as
29:02merely a
29:02kind of
29:03electricity
29:03were two
29:04great successes
29:06for Franklin
29:06and the
29:07new
29:07Enlightenment
29:08movement.
29:11But the
29:12forces of
29:13trade and
29:13commerce,
29:14which helped
29:15fuel the
29:16Enlightenment,
29:16were about to
29:17throw up a
29:18new and even
29:19more perplexing
29:21electrical
29:21mystery,
29:22a completely
29:23new kind
29:25of electricity.
29:30This is the
29:32English Channel.
29:33By the 17th
29:34and 18th
29:35centuries,
29:36a good fraction
29:37of the world's
29:37wealth flowed up
29:39this stretch of
29:40water from all
29:41corners of the
29:41British Empire
29:42and beyond,
29:43on its way to
29:44London.
29:45Spices from
29:46India,
29:47sugar from the
29:47Caribbean,
29:48wheat from
29:49America,
29:49tea from
29:50China.
29:51But of course,
29:52it wasn't just
29:53commerce.
29:57New plant and
29:59animal specimens
30:00from all over the
30:01world came flooding
30:02into London,
30:03including one that
30:05particularly fascinated
30:07the electricians.
30:11Called the
30:12torpedo fish,
30:13it'd been the
30:14stuff of
30:14fishermen's
30:15tails.
30:16Its sting,
30:17it was said,
30:18was capable of
30:19knocking a
30:19grown man down.
30:22But as the
30:23electricians started
30:24to investigate
30:25the sting,
30:26they realised
30:27it felt strangely
30:28similar to a
30:29shock from a
30:30Leiden jar.
30:34Could its sting
30:35actually be an
30:36electric shock?
30:42At first,
30:43many people
30:44dismissed the
30:44torpedo fish's
30:45shock as
30:46occult.
30:47Some said it
30:48was probably just
30:49the fish biting.
30:50Others that it
30:52couldn't be a
30:52shock because
30:53without a spark,
30:54it just wasn't
30:55electricity.
30:56But for most,
30:57this was a very
30:58strange and
30:59inexplicable new
31:00mystery.
31:01And it would
31:01take one of the
31:02oddest yet most
31:03brilliant characters
31:04in British science
31:05to begin to
31:06unlock the secrets
31:08of the torpedo
31:08fish.
31:14of Henry Cavendish.
31:15This is the only
31:16picture in existence
31:17of the pathologically
31:19shy but
31:20exceptional Henry
31:21Cavendish.
31:22This one only
31:24exists because an
31:25artist sketched his
31:27coat as it hung on a
31:28peg, then filled in the
31:30face from memory.
31:35His family were
31:36fantastically rich.
31:38They were the
31:39Devonshires, who
31:40still own Chatsworth
31:41House in Derbyshire.
31:44But Henry Cavendish
31:46decided to turn his
31:47back on his family's
31:48wealth and status to
31:50live in London, near
31:51his beloved royal
31:52society, where he
31:54could quietly pursue
31:55his passion for
31:56experimental science.
31:58When he heard about
32:00the electric torpedo
32:01fish, he was
32:02intrigued.
32:03A friend wrote to
32:05him, on this, my
32:06first experience of
32:08the effect of the
32:09torpedo, I exclaimed
32:11that this is
32:11certainly electricity.
32:14But how?
32:16And to work out how
32:18a living thing could
32:20produce electricity, he
32:21decided to make his
32:23own artificial fish.
32:27These are his plans.
32:30Two Leiden jars, shaped
32:32like the fish, which
32:33were buried under sand.
32:35When the sand was
32:36touched, they discharged,
32:38giving a nasty shock.
32:40His model helped
32:42convince him that the
32:43real torpedo fish was
32:45electric.
32:46But it still left him
32:48with a nagging problem.
32:51Although both the real
32:53fish and Cavendish's
32:55artificial one gave
32:56powerful electric shocks,
32:58the real fish never
33:00sparked.
33:02Cavendish was perplexed.
33:03How could it be the same
33:05kind of electricity if they
33:08didn't both do the same
33:09kinds of things?
33:12Cavendish spent the
33:13winter of 1773 in his
33:16laboratory, trying to come
33:18up with an answer.
33:18And in the spring, he had
33:21a brainwave.
33:24Cavendish's ingenious answer
33:26was to point out a subtle
33:27distinction between the
33:29amount of electricity and
33:31its intensity.
33:32The real fish produced the
33:34same kind of electricity,
33:36it's just that it was less
33:37intense.
33:39Now, for a physicist like me,
33:40this marks a crucial
33:42turning point, because it's
33:43the moment when two genuinely
33:45innovative scientific ideas
33:47first crop up.
33:49What Cavendish refers to as the
33:51amount of electricity, we now
33:53call electric charge.
33:55And his intensity is what we
33:58call the potential difference,
34:00or voltage.
34:04So the Leiden jar's shock was
34:07high voltage but low charge,
34:10whereas the fish was low
34:12voltage and high charge.
34:14And it's possible to actually
34:17measure that.
34:21Hiding at the bottom of this
34:23tank under the sand is the
34:25torpedo marmorata, and it's an
34:27electric ray.
34:28You can just see his eyes
34:30protruding from the sand.
34:32This is a fully grown female,
34:34and I'm going to try and
34:36measure the electricity it
34:38gives off with this bait.
34:40I've got this fish connected
34:41to a metal rod and hooked up
34:43to an oscilloscope to see if I
34:45can measure the voltage as it
34:47catches its prey.
34:49So, here goes.
35:03Oh, there's one.
35:09And there's another one.
35:11The fish gave a shock of about
35:13240 volts, the same as mains
35:16electricity, but still roughly
35:19ten times less than the Leiden
35:21jar.
35:22Well, that would have given me
35:24quite a nasty shock, and I can
35:27only try and imagine what it
35:28must have been like for
35:29scientists in the 18th century
35:30to witness this.
35:32An animal, a fish, producing
35:34its own electricity.
35:39Cavendish had shown that the
35:40torpedo fish made electricity,
35:43but he didn't know if it was
35:45the same kind of electricity
35:46as that made from an
35:48electrical machine.
35:50Is the electrical shock that
35:53a torpedo produces, is it the
35:55same as produced by an
35:57electrical machine, or are
35:59there two kinds?
36:00Is there a kind that's
36:01generated artificially, or is
36:03there a kind of animal
36:04electricity that only exists in
36:07living bodies?
36:08This was a huge debate that
36:09divided opinion for several
36:14decades.
36:15And out of that bitter debate
36:18came a new discovery.
36:20The discovery that electricity
36:22needn't be a brief shock or
36:24spark, but could actually be
36:26continuous.
36:28And the generation of
36:29continuous electricity would
36:32ultimately propel us into our
36:34modern age.
36:48But the next step in the story
36:50of electricity would come about
36:52because of a fierce personal
36:54and professional rivalry
36:55between two Italian
36:57academics.
37:13This is Bologna University, one of
37:16the oldest in Europe.
37:18In the late 18th century, the city
37:20of Bologna was ruled from papal Rome,
37:23which meant that the university
37:24was powerful, but conservative
37:26in its thinking.
37:31It was steeped in traditional
37:33Christianity, one where God ruled
37:36earth from heaven, but that the way
37:39he ran the world was hidden from us
37:41mere mortals.
37:42We were not meant to understand him,
37:45only to serve him.
37:47And one of the university's
37:49brightest stars was the
37:51anatomist Luigi Alizio Galvani.
37:54But in a neighbouring city,
37:56a rival electrician was about
37:59to take Galvani to task.
38:10This is Pavia, only 150 miles
38:14from Bologna, but by the end
38:16of the 18th century, worlds
38:18apart politically.
38:19It was part of the Austrian
38:20empire, which put it at the very
38:22heart of the European
38:24Enlightenment.
38:25Liberal in its thinking,
38:27politically radical, and
38:28obsessed with the new science
38:30of electricity.
38:31It was also home to Alessandro
38:34Volta.
38:39Alessandro Volta couldn't have
38:41been more unlike Galvani.
38:43From an old Lombardy family,
38:45he was young, arrogant,
38:47charismatic, a real ladies'
38:50man, and he courted
38:51controversy.
38:52Unlike Galvani, he liked to
38:54show off his experiments on an
38:55international stage to any
38:57audience.
39:00Volta's ideas were unfettered by
39:02Galvani's religious dogma.
39:05Like Benjamin Franklin and the
39:07European Enlightenment, he believed
39:09he believed in rationality, that
39:11scientific truth, like a Greek
39:14god, would cast ignorance to the
39:16floor.
39:17Superstition was the enemy,
39:20reason was the future.
39:25Both men were fascinated by
39:27electricity, and both brought their
39:29different ways of seeing the world
39:31the world to bear on it.
39:45Galvani had been attracted to the use of
39:47electricity in medical treatments.
39:50For instance, in 1759, here in Bologna,
39:53electricity was used on the muscles of a
39:56paralysed man.
39:58One report said it was a fine sight to
40:03see the mastoid rotate the head, the
40:07biceps bend the elbow, in short, to see
40:11the force and vitality of all the
40:13motions occurring in every paralysed
40:16muscle subjected to the stimulus.
40:27Galvani believed these kinds of
40:29examples revealed that the body worked
40:32using animal electricity, a fluid that
40:36flows from the brain through the
40:38nerves into the muscles where it's
40:40turned into motion.
40:43And he devised a series of grisly
40:46experiments to prove it.
41:02Now, he first prepared a frog.
41:06He writes, the frog is skinned and
41:09disemboweled, only their lower limbs are
41:11left joined together, containing just the
41:12crural nerves.
41:14Well, I've left my frog mostly intact,
41:16but I've exposed the nerves that connect to
41:19the frog's legs.
41:21Then he used Hawksby's electrical machine
41:24to generate electrostatic charge that
41:28would accumulate and travel along this
41:30arm and out through this copper wire.
41:34Then he connected the charge-carrying wire to
41:38the frog and another to the nerve just above the leg.
41:43Let's see what happens.
41:47Oh, and the frog's leg twitches just as he makes contact.
41:52There we go.
41:55Now, for Galvani, what was going on there was that
41:59there's a strange, special kind of entity in the animal muscle,
42:05which he calls animal electricity.
42:07It's not like any other electricity.
42:09It's intrinsic to living beings.
42:14But for Volta, animal electricity smacked of superstition and magic.
42:21It had no place in rational and enlightened science.
42:28Volta saw the experiment completely differently to Galvani.
42:32He believed it revealed something totally new.
42:36For him, the legs weren't jumping as a result of the release of animal electricity
42:41from within them, but because of the artificial electricity from outside.
42:45The legs were merely the indicator.
42:48They were only twitching because of the electricity from the Hawksby machine.
42:56Back in Bologna, Galvani reacted furiously to Volta's ideas.
43:02He believed Volta had crossed a fundamental line,
43:06from electrical experiment into God's realm.
43:09And that was tantamount to heresy.
43:13To have a kind of spirit like electricity,
43:17to have that produced artificially,
43:19and to say that that spirit, that living force, that agency,
43:23was the same as something produced by God,
43:26that God had put into a living human body or a frog's body,
43:30that seemed sacrilegious to them
43:32because it was eliminating this boundary
43:34between God's realm of the divine
43:37and the mundane realm of the material.
43:44Spurred on by his religious indignation,
43:47Galvani announced a new series of experimental results
43:50which would prove that Volta was wrong.
43:55During one of his experiments,
43:57he hung his frogs on an iron wire
44:00and saw something totally unexpected.
44:04If he connected a copper wire to the wire the frog was hanging from
44:09and then touched the other end of the copper to the nerve,
44:15it seemed to him that he could make the frog's leg twitch
44:18without any electricity at all.
44:29Galvani came to the conclusion
44:31that it must have been something inside the frogs,
44:37even if dead,
44:38that continued for a while after death
44:41to produce some kind of electricity.
44:45And the metal wires were somehow releasing that electricity.
44:51Over the next months,
44:53Galvani's experiments focused on isolating this animal electricity
44:57using combinations of frog and metal,
45:01Leiden jars and electrical machines.
45:04For Galvani,
45:06these experiments were proof
45:08that the electricity was originating within the frog itself.
45:12The frog's muscles were Leiden jars,
45:15storing up the electrical fluid
45:17and then releasing it in a burst.
45:19On the 30th of October, 1786,
45:23he published his findings in a book,
45:26De Animale Electricitate,
45:28of animal electricity.
45:32Galvani was so confident of his ideas,
45:35he even sent a copy of his book to Volta.
45:40But Volta just couldn't stomach Galvani's idea of animal electricity.
45:45He thought the electricity just had to come from somewhere else.
45:51But where?
46:03In the 1790s, here at the University of Pavia,
46:07almost certainly in this lecture theatre,
46:09which still bears his name,
46:12Volta began his search
46:13for the new source of electricity.
46:17His suspicions focused on the metals
46:21that Galvani had used to make his frog's legs twitch.
46:24His curiosity had been piqued
46:27by an odd phenomenon that he'd come across,
46:30how combinations of metals tasted.
46:35He found that if he took two different metal coins
46:39and placed them on the tip of his tongue
46:42and then placed a silver spoon on top of both,
46:47he got a kind of tingling sensation,
46:50rather like the tingling you'd get from the discharge of a Leiden jar.
46:54Volta concluded that he could taste electricity
46:57and that it must be coming from the contact
47:00between the different metals in the coins and spoon.
47:04His theory flew in the face of Galvani's.
47:07The frog's leg twitched not because of its own animal electricity,
47:11but because it was reacting to the electricity from the metals.
47:15But the electricity his coins generated was incredibly weak.
47:21How could he make it stronger?
47:28Then an idea came to him
47:30as he revisited the scientific papers
47:33from the great British scientist Henry Cavendish,
47:36and in particular,
47:38his famous work on the electric torpedo fish.
47:45He went back and took a closer look at the torpedo fish,
47:49and in particular,
47:50the repeating pattern of chambers in its back.
47:53He wondered whether it was this repeating pattern
47:56that held the key to its powerful electric shock.
48:02Perhaps each chamber was like his coins and spoon,
48:06each generating a tiny amount of electricity.
48:10And perhaps the fish's powerful shock
48:13results from the pattern of chambers
48:15repeating over and over again.
48:20With growing confidence in his new ideas,
48:23Volta decided to fight back
48:25by building his own artificial version of the torpedo fish.
48:31So he copied the torpedo fish
48:34by repeating its pattern,
48:35but using metal.
48:38Here's what he did.
48:39He took a copper metal plate
48:42and then placed above it
48:43a piece of card soaked in dilute acid.
48:47Then above that,
48:48he took another metal and placed it on top.
48:50What he had here was exactly the same thing
48:53as Galvani's two wires.
48:56But now,
48:57Volta repeated the process.
49:00What he was doing here
49:01was building a pile of metal.
49:04In fact,
49:05his invention became known
49:07as the pile.
49:13But it's what it could do
49:15that was the really incredible revelation.
49:18Volta then tried his pile out on himself
49:20by getting two wires
49:22and attaching them to each end of the pile
49:24and bringing the other ends to touch his tongue.
49:29He could actually taste the electricity.
49:32This time,
49:33it was more powerful than normal
49:35and it was constant.
49:41He'd created the first battery.
49:45The machine was no longer
49:48an electrical and mechanical machine.
49:50It was just a purely electrical machine.
49:53So he proved
49:55that a machine imitating the fish could work,
49:58that what he called the metal
50:01or compact electricity
50:03of different metals could work.
50:05And that he regarded as
50:07his final winning move
50:11in the controversy with Galvani.
50:14What Volta's pile showed
50:16was that you could develop
50:18all the phenomena
50:19of animal electricity
50:21without any animals being present.
50:24So from the Voltaic point of view,
50:27it seemed as if Galvani was wrong.
50:30There's nothing special
50:31about the electricity in animals.
50:34It's electricity
50:35and it can be completely mimicked
50:38by this artificial pile.
50:42But the biggest surprise for Volta
50:44was that the electricity it generated
50:47was continuous.
50:48In fact, it poured out like water in a stream.
50:52And just as in a stream
50:54where the measure of the amount of water flowing
50:57is called a current,
50:59so the electricity flowing out of the pile
51:02became known as an electrical current.
51:10200 years after Volta,
51:13we finally understand what electricity actually is.
51:18The atoms in metals, like all atoms,
51:22have electrically charged electrons
51:24surrounding a nucleus.
51:26But in metals,
51:28the atoms share their outer electrons
51:30with each other in a unique way,
51:32which means they can move
51:34from one atom to the next.
51:38If those electrons move in the same direction
51:42at the same time,
51:43the cumulative effect
51:45is a movement of electric charge.
51:49This flow of electrons
51:51is what we call an electric current.
52:00Within weeks of Volta publishing details of his pile,
52:03scientists were discovering something incredible
52:06about what it could do.
52:15Its effect on ordinary water
52:18was completely unexpected.
52:20The constant stream of electric charge
52:22into the water
52:23was ripping it up
52:25into its constituent parts,
52:27the gases oxygen and hydrogen.
52:30Electricity was heralding the dawn
52:33of a new age.
52:35A new age where electricity
52:37ceased being a mere curiosity
52:39and started being genuinely useful.
52:43With constant flowing current electricity,
52:47new chemical elements
52:48could be isolated with ease.
52:50And this laid the foundations
52:52for chemistry, physics
52:55and modern industry.
52:59Volta's pile changed everything.
53:07The pile made Volta
53:09The pile made Volta
53:09an international celebrity,
53:11fated by the powerful and the rich.
53:15In recognition,
53:16a fundamental measure of electricity
53:18was named in his honour,
53:21the vault.
53:26But his scientific adversary
53:28didn't fare quite so well.
53:32Luigi Alizio Galvani died on the 4th of December, 1798,
53:38depressed and in poverty.
53:41For me, though,
53:42it's not the invention of the battery
53:44that marks the crucial turning point
53:47in the story of electricity.
53:49It's what happened next.
54:01It took place
54:02in London's Royal Institution.
54:04It was a moment
54:06that marked the end
54:07of one era
54:08and the beginning
54:09of another.
54:14It was overseen
54:16by Humphrey Davy,
54:17the first of a new generation
54:19of electricians,
54:20young, confident
54:22and fascinated
54:23by the possibilities
54:24of continuous electrical current.
54:28So in 1808,
54:30he built
54:31the world's largest battery.
54:33It filled an entire room
54:35underneath the Royal Institution.
54:37It had over 800
54:39individual
54:41voltaic piles
54:42attached together.
54:44It must have hissed
54:46and breathed
54:47sulphurous fumes.
54:50In a darkened room
54:52lit by centuries-old technology,
54:55candles
54:56and oil lamps,
54:58Davy
54:58connected his battery
55:00to two
55:01carbon filaments
55:02and brought
55:03the tips
55:03together.
55:04The continuous flow
55:06of electricity
55:06from the battery
55:07through the filaments
55:09leapt across the gap,
55:11giving rise
55:11to a constant
55:13and blindingly bright
55:14spark.
55:22Out of the darkness
55:23came the light.
55:38Davy's arc light
55:40truly symbolises
55:41the end
55:42of one era
55:43and the beginning
55:44of our era,
55:46the era
55:47of electricity.
55:59But there's a truly
56:00grisly coda
56:01to this story.
56:03In 1803,
56:05Galvani's nephew,
56:07one Giovanni Aldini,
56:09came to London
56:10with a terrifying
56:11new experiment.
56:12A convicted murderer
56:14called George Forster
56:15had just been hanged
56:16in Newgate,
56:17and when the body
56:18was cut down
56:19from the gallows,
56:20it was brought
56:21directly to the
56:22lecture theatre
56:23where Aldini
56:24started his
56:25macabre work.
56:29Using a voltaic
56:31pile,
56:32he began
56:32to apply
56:33an electric current
56:35to the dead man's body.
56:37Then,
56:38Aldini put
56:39one electrical conductor
56:41in the dead man's
56:42anus
56:42and the other
56:43at the top
56:44of his spine.
56:45Forster's limp,
56:47dead body
56:47sat bolt upright
56:49and his spine
56:50arched and twisted.
56:52For a moment,
56:53it seemed as though
56:54the dead body
56:55had been brought
56:56back to life.
56:59It appeared
57:00as though electricity
57:01might have
57:03the power
57:03of resurrection.
57:05And this
57:06made a profound
57:07impact
57:08on a young writer
57:09called Mary Shelley.
57:16Mary Shelley
57:18wrote one of the
57:18most powerful
57:19and enduring
57:20stories ever.
57:22Based partly
57:23here on Lake Como,
57:24Frankenstein
57:25tells the story
57:26of a scientist,
57:27a galvanist,
57:28probably based
57:29on Aldini,
57:30who brings
57:31a monster to life
57:32using electricity.
57:33And then,
57:34disgusted
57:35by his own arrogance,
57:36he abandons
57:37his creation.
57:39Just like
57:40Davy's
57:41Arc Lamp,
57:41this book
57:42symbolises
57:43changing times,
57:45the end
57:45of the era
57:46of miracles
57:47and romance
57:48and the beginning
57:49of the era
57:50of rationality,
57:52industry
57:52and science.
58:05And it's
58:06that new age
58:07we explore
58:08in the next
58:09programme,
58:10because at the
58:11start of the
58:1119th century,
58:12scientists realised
58:14that electricity
58:15was intimately
58:16connected with
58:17another of
58:18nature's
58:19mysterious forces,
58:20magnetism.
58:21And that
58:23realisation
58:24would completely
58:25transform our
58:27world.
58:29To find out
58:30more about
58:31the story
58:31of electricity
58:32and to put
58:33your power
58:33knowledge to
58:34the test,
58:35try the
58:36Open University's
58:37interactive
58:38energy game.
58:39Go to
58:40bbc.co.uk
58:41forward slash
58:43electricity
58:43and follow
58:44links to
58:45the Open
58:45University.
58:51And the
58:52story of
58:52electricity
58:52continues here
58:53on BBC
58:54HD on
58:55Thursday at
58:5511.
58:56Coming up
58:57next this
58:57evening,
58:58we're paying
58:58our regular
58:59monthly visit
59:00to the sky
59:00at night.
59:01public
59:02Bye.
59:11Bye.
59:14Bye.
59:18Bye.
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