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Who Discovered the Electricity?

 Who Discovered the Electricity - The story of   Electricity




Ben Franklin Discovered the Electricity.


Let us tell you the story of Electricity:

At the dawn of the 19th century in a

cellar in Mayfair the most famous

scientist of the time Humphrey Davy

built an extraordinary piece of

electrical equipment four metres wide

twice as long and containing stinking

stacks of acid and metal it had been

created to pump out more electricity

than had ever been possible before it

was in fact the biggest battery the

world had ever seen

and with it Davy was about to propel us

into a new age.

That moment would take place at a

lecture at the Royal Institution in

front of hundreds of London's great and

good filled with anticipation they

packed the seats hoping to witness a new

and exciting electrical wonder, but what

they would see that night will be

something truly unique something they'd

remember for the rest of their lives

using just two simple carbon rods

Humphrey Davy was about to unleash the

true potential of electricity.



Electricity is one of nature's most

awesome phenomena and the most powerful

manifestation of it we ever see is

lightning.

This is the story of how we first

dreamed of controlling this primal force

of nature and how we would ultimately

become its master. It's a 300 year tale

of dazzling leaps of imagination and

extraordinary experiments.

It's a story

of maverick geniuses who used

electricity to light our cities to

communicate across the seas and through

the air to create modern industry and to

give us the digital revolution.

We'll tell the story of

the very first scientists who started to

unlock the mysteries of electricity is

there something alive in there

they studied it's curious link to life

build strange and powerful instruments

to create it and even tamed lightning

itself.

It was these men who truly laid the

foundations of the modern world and it

all started with a spark.

Imagine our

world without electricity it will be

darn cold and quiet in many ways it will

be like the beginning of the 18th

century where how story begins.



This is the Royal Society in London in

the early 1700s after years in the

wilderness Isaac Newton finally took

control of it after the death of his

arch enemy Robert Hooke Newton brought

in his own people to the key jobs to

help shore up his new position the new

head of demonstrations there was 35 year

old Frances Hawkes Be.

Notes from the

Royal Society in 1705 reveal how hard

Hawks be tried to stamp his personality

on its weekly meetings producing ever

more spectacular experiments to impress

his masters in November he came up with

this a rotating glass sphere, he was able

to remove the air from inside it using a

new machine the air pump on his machine

a handle allowed him to spin the sphere

one by one the tangles in the room will

put out and Francis placed his hand

against the sphere the audience were

about to see something amazing.



Inside the glass sphere a strange

ethereal light began to form dancing

around his hand a light no one had ever

seen before that's fantastic

a suit beautiful blue glows is marking

out the shape of my hands but then going

like round the board there's something

alive in there.

It's difficult to really understand why

this dancing blue light meant so much

but we have to bear in mind that at the

time natural phenomena like this was

seen to be the work of the Almighty this

was still a period when even in Isaac

Newton's theory God was constantly

intervening in the conduct of the world

and so it made sense for a lot of people

to interpret natural phenomena as acts

of God so when a mere mortal meddled

with God's work.

It was almost beyond rational

comprehension Hawks we never realized

the full significance of his experiment

he lost interest in his glowing sphere

and spent the last few years of his life

building ever more spectacular

experiments for Isaac Newton to test his

other theories he never realized that it

unwittingly started an electrical

revolution before Hawke's Bay

electricity had been merely a curiosity

the ancient Greeks rubbed amber which

they called electron to get small shocks

an even Queen Elizabeth the first

marveled of static electricity power to

lift feathers but now Hawkes bees

machine could make electricity at the

turn of a handle and you could see it

and perhaps even more importantly his

invention coincided with the birth of a

new movement sweeping across Europe

called the Enlightenment enlightened

intellectuals used reason to question

the world and their legacy was radical

politics iconoclastic art and natural

philosophy or science but ironically

Hawkes B's new machine wasn't

immediately embraced by most of these

intellectuals but instead by conjurer's

and street magicians and those with an

interest in electricity called

themselves electricians one story tells

of a dinner party attended by an

Austrian count the electrician had

placed some feathers on the table and

then charged up a glass rod with a silk

handkerchief he then astonished the

guests by lifting up the feathers with

the rod he then went on to charge

himself up using one of Hawkes B's

electrical machines and gave the guests

electric shocks presumably to squeals of

delight but for his ps2 resistance

he placed a glass of cognac in the

center of the table charged himself up

again and lit it with a spark from the

tip of his finger there was a trick

called the electrical beatification in

which the victim sits on an insulated

chair and above his head hangs a metal

crown that doesn't quite touch his head

and then if the crown is electrified

then you get an electric discharge

around the crown that looks exactly like

a halo which is why it's called the

electric beatification

as England and the rest of Europe went

electricity crazy the spectacles grew

bigger and the more curious electricians

started to ask more profound questions

not only how can we make our shows

bigger and better but how can we control

this amazing power and for some can this

incredible electrical fire do more than

just entertain.

 

One of the first early breakthroughs

would never have happened had it not

been for a terrible accident

this is Charterhouse in the center of

London over the past 400 years it's been

a charitable home for young orphans and

elderly gentlemen and sometime in the

1720s it also became home to one Steven

gray Steven gray had been a successful

silk Dyer from Canterbury he was used to

seeing electric sparks leap from the

silk and they fascinated him

unfortunately a crippling accident ended

his career and left him destitute but

then he was offered a new life here at

Charterhouse and with it

the time to perform his own electrical

experiments here at Charterhouse

possibly in this very room the great

chamber Steven grade built a wooden

frame from the top beam he suspended two

swings using silk rope he also had a

device like this a hawk's B machine for

generating static electricity now with a

large audience and attendance he got one

of the orphan boys who lived here at

Charterhouse to lie across the two

swings,

gray placed some gold leaf in front of

him,

 

he then generated electricity and

charged the boy through a connecting rod.

 

Gold leaf even feathers left to the boys

fingers some of the audience claimed

they could even see sparks flying out

from his fingertips show business indeed.

 

But to the curious and inquiring mind of

Stephen gray this said something else as

well.

Electricity could move from the machine

to the boy's body through to his hands

but the silk rope stopped it dead

it meant the mysterious electrical fluid

could flow through some things but not

through others.

 

It led gray to divide the world into two

different kinds of substances

he called them insulators and conductors

insulators held electric charge within

them and wouldn't let it move like the

silk or hair glass and resin

whereas conductors allowed electricity

to flow through them like the boy or

metals it's a distinction which is still

crucial even today just think of these

electric pylons they work on the same

principle that graded used nearly 300

years ago the wires are conductors the

glass and ceramic objects between the

wire and the metal of the pylon are

insulators that stop the electricity

leaking from the wires into the pylon

and down to the earth

they're just like the silk ropes in

Gray's experiment back in the 1730's

grey's experiment may have astounded all

who saw it but it had a frustrating

drawback try as he might grey couldn't

contain the electricity he was

generating for long it left from the

machine to the boy and was quickly gone

the next step in our story came when we

learnt how to store electricity but that

would take place not in Britain but

across the channel in mainland Europe.

 

Across the channel electricians were

just as busy as their British

counterparts and one Center for

electrical research was here in Leiden

Holland.

 

And it was here that a professor came up

with an invention that many still regard

as the most significant of the 18th

century one that in some form or another

can still be found in almost every

electrical device today that professor

was Pieter van mushin Brooke unlike

Hawkes being gray mission Brooke was

born into academia but ironically enough

his breakthrough came not because of his

rigorous science but because of a simple

human mistake he was trying to find a

way to store electrical charge ready for

his demonstrations and you can almost

hear his train of thought as he tries to

figure this out if electricity is a

fluid that flows a bit like water then

maybe you can store it in the same way

that you can store water so mission

Brooke went to his laboratory to try to

make a device to store electricity

motion Brooke started to think literally

he took a glass jar and poured in some

water he then placed inside it a length

of conducting wire which was connected

at the top to a hawk speed electric

machine then he put the jar on an

insulator to help keep the charge in the

jar he then tried to pour the

electricity into the jar produced by the

machine via the wire down through into

the water but whatever he tried the

charge just wouldn't stay in the jar

then one day by accident he forgot to

put the jar on the insulator but charges

instead while it was still in his hand.

 

Finally holding the jar with one hand he

touched the top with the other and

received such a powerful electric shock

he was almost thrown to the ground

he writes it's a new but terrible

experiments which I advise you never to

try nor would I who've experienced it

and survived by the grace of God do it

again.

For all the kingdom of France so I'm

going to heed his advice not touch the

top but instead see if I can get a spark

off of it the sheer power of the

electricity which flew from the jar was

greater than any seen before and even

more surprisingly the jar could store

that electricity for hours even days so

in honor of the city where motion Brooke

made his discovery they called it the

Leyden jar

and it's Fame swept across the world and

very rapidly from 1745 through the rest

of the 1740s the news of this it's

called the Leyden jar goes global it

spreads from Japan in East Asia to

Philadelphia in eastern America it

became one of the first quick globalized

scientific news items but although the

Leyden jar became a global electrical

phenomenon no one had the slightest idea

how it worked you have a jar of electric

fluid and it turns out that you get a

bigger shock from the jar if you allow

the electric fluid to drain away to the

earth why is the shock bigger if the

jars leaking why isn't the shock bigger

if you make sure that all the electric

fluid stays inside the jar that was how

mid 18th century electrical philosophers

were faced with this challenge.

 

Electricity was without doubt a

fantastical wonder it could shock and

spark it could now be stored and moved

around yet what electricity was how it

worked and why did all these things was

nothing less than a complete mystery.

 

Within ten years a new breakthrough was

to come from an unexpected quarter from

a man politically and philosophically at

war with the London establishment and

even more shockingly for the British

electrical elite that man was merely a

colonial an American this painting of

Benjamin Franklin hangs here at the

Royal Society in London Franklin was a

passionate supporter of American

emancipation and saw the pursuit of

rational science and particularly

electricity as a way of rolling back

ignorant false idols and ultimately his

intellectually elitist colonial masters

and this is mixed with a profoundly

egalitarian Democratic idea that

Franklin and his allies have which is

this is a phenomenon open to everyone

here's something that the elite doesn't

really understand and we might be able

to understand it here's something that

the elite can't really control but we

might be able to control and here's

something above all which is the source

of superstition and we rational

egalitarian potentially democratic

intellectuals we will be able to reason

it out without appearing to be the

slaves of magic or mystery

so Franklin decided to use the power of

reason to rationally explain what many

considered a magical phenomenon

lightning this is probably one of the

most famous scientific images of the

18th century

it shows Benjamin Franklin the heroic

scientist flying a kite in a storm

proving that lightning is electrical

but although Franklin proposed this

experiment he almost certainly never

performed it much more likely is that

his most significant experiment was

another one which he proposed but didn't

even conduct in fact it didn't even

happen in America it took place here in

a small village north of Paris called

Mali level the French adored Franklin

especially his anti British politics and

they took it upon themselves to perform

his other lightning experiments without

him.

I've come to the very spot where that

experiment took place

 in May 1750 to George Louis LeClair

known across France as the Comte de

Buffon and his friend Thomas Francois de

Labarre erected a 40-foot metal pole

more than twice as high as this one held

in place by three wooden staves just

outside deli bars house here in Mali

level the metal pole rested at the

bottom inside an empty wine bottle

Franklin's big idea had been that the

long pole would capture the lightning

pass it down the metal rod and store it

in the wine bottle at the base which

worked as a Leyden jar then he could

confirm what lightning actually was all

his French followers had to do was wait

for a storm and then on May 23rd the

heavens opened at 12:20 a loud

thunderclap was heard as lightning hit

the top of the pole

an assistant ran to the bottle a spark

left a cross between the metal and his

finger with a loud crack and a sulfurous

smell burning his hand the spark

revealed lightning for what it really

was

it was the same as the electricity made

by man it's hard to overestimate the

significance of this moment Nature had

been mastered not only that but the

wrath of God itself had been brought

under the control of mankind it was a

kind of heresy Franklin's experiment was

very important because it showed that

lightning storms produce or are produced

by electricity and that you can bring

this electricity down electricity is a

force of nature that's waiting out there

to be tapped next Franklin turned his

rational mind to another question why

the Leyden jar made the biggest sparks

when it was held in the hand why didn't

all the electricity just drain away and

drawing on his experience as a

successful businessman he saw something

no one else had that liked money in a

bank electricity can be in credit what

he called positive or debit negative for

him the problem of the Leyden jar is a

problem of Accountancy Franklin's idea

was every body has around it an

electrical atmosphere and there's a

natural amount of electric fluid around

each body if there's too much we'll call

it positive if there's too little we'll

call it negative and nature is organized

so the positives and the negatives

always want to balance out like an ideal

American economy

Quinn's insight was that electricity was

actually just positive charge flowing to

cancel out negative charge and he

believed this simple idea could solve

the mystery of the Leyden jar as the jar

is charged up negative electrical charge

is poured down the wire and into the

water

if the jar rests on an insulator a small

amount builds up in the water but if

instead the jar is held by someone as

it's being charged positive electric

charge is sucked up through their body

from the ground to the outside of the

jar trying to cancel out the negative

charge inside but the positive and

negative charges are stopped from

cancelling out by the glass which acts

as an insulator so instead the charge

just grows and grows on both sides of

the glass

then touching the top of the jar with

the other hand completes a circuit

allowing the negative charge on the

inside to pass through the hand to the

positive on the outside

finally canceling it out

the movement of this charge causes a

massive shock and often a spark the

modern equivalents of the Leyden jar is

this the capacitor and it's one of the

most ubiquitous of electronic components

is found everywhere there are a number

of smaller ones scattered around on this

circuit board from a computer they help

smooth out electrical surges protecting

sensitive components even in the most

modern electric circuit solving the

mystery of the Leyden jar and

recognizing lightning as merely a kind

of electricity with two great successes

for Franklin and the new enlightenment

movement

 but the forces of trade and commerce

which helped fuel the Enlightenment were

about to throw up a new and even more

perplexing electrical mystery a

completely new kind of electricity this

is the English Channel by the 17th and

18th centuries a good fraction of the

world's wealth flowed up this stretch of

water from all corners of the British

Empire and beyond on its way to London

spices from India sugar from the

Caribbean wheat from America tea from

China but of course it wasn't just

commerce

new plants and animal specimens from all

over the world came flooding into London

including one that particularly

fascinated the electrician's called the

torpedo fish it been the stuff of

fishermen's tales its sting it was said

was capable of knocking a grown man down

but as the electricians started to

investigate the sting they realized it

felt strangely similar to a shock from a

Leyden jar could it sting actually be an

electric shock but first many people

dismiss the torpedo fish as shocked as a

cult some said it was probably just the

fish biting

others that it couldn't be a shock

because without a spark it just wasn't

electricity but for most this was a very

strange and inexplicable new mystery and

it would take one of the oddest yet most

brilliant characters in British science

to begin to unlock the secrets of the

torpedo fish

this is the only picture in existence of

the pathologically shy but exceptional

Henry Cavendish this one only exists

because an artist sketched his coat as

it hung on a peg then filled in the face

from memory

his family were fantastically rich they

were the Devonshire's who still owned

Chatsworth House in Derbyshire but Henry

Cavendish decided to turn his back on

his family's wealth and status to live

in London near his beloved Royal Society

where he could quietly pursue his

passion for experimental science when he

heard about the electric torpedo fish he

was intrigued a friend wrote to him on

this my first experience of the effects

of the torpedo I exclaimed that this is

certainly electricity but how and to

work out how a living thing could

produce electricity he decided to make

his own artificial fish

these are his plans to Leyden jars

shaped like the fish which were buried

under sand when the sand was touched

they discharged giving a nasty shock his

model helped convince him that the real

torpedo fish was electric but it still

left him with a nagging problem although

both the real fish and Cavendish's

artificial one gave powerful electric

shocks the real fish never sparked

Cavendish was perplexed how could it be

the same kind of electricity if they

didn't both do the same kinds of things

Cavendish spent the winter of 1773 in

his laboratory trying to come up with an

answer and in the spring he had a

brainwave Cavendish's ingenious answer

was to point out a subtle distinction

between the amount of electricity and

its intensity the real fish

produced the same color

of electricity is just that it was less

intense now for a physicist like me this

marks a crucial turning point because

it's the moment when two genuinely

innovative scientific ideas first crop

up what Cavendish refers to as the

amount of electricity we now call

electric charge and his intensity is

what we call the potential difference of

voltage so the Leyden jars shock was

high voltage but low charge whereas the

fish was low voltage and high charge and

it's possible to actually measure that

hiding at the bottom of this tank under

the sand is the torpedo Mar Murata and

it's an electric ray you can just see

his eyes protruding from the sand this

is a fully grown female and I'm going to

try and measure the electricity it gives

off with this bait I've got this fish

connected to a metal rod and hooked up

to an oscilloscope to see if I can

measure the voltage as it catches its

prey so here goes

oh there's one

 

and there's another one the fish gave a

shock of about 240 volts the same as

mains electricity but still roughly ten

times less than the Leyden jar well that

would have given me quite a nasty shock

and I can only to try and imagine what

it must have been like for scientists in

the 18th century to witness this an

animal a fish producing its own

electricity

Cavendish had shown that the torpedo

fish made electricity but he didn't know

if it was the same kind of electricity

as that made from an electrical machine

is the electrical shock that a torpedo

producers is it the same as produced by

an electrical machine or are there two

kinds as a kind that's generated

artificially or is there a kind of

animal electricity that only exists in

living bodies as is a huge debate that

divided opinion for several decades

and out of that bitter debate came a new

discovery the discovery that electricity

needn't be a brief shot or spark but

could actually be continuous and the

generation of continuous electricity

would ultimately propel us into our

modern age

 

but the next step in the story of

electricity would come about because of

a fierce personal and professional

rivalry between two Italian academics

 

this is Bologna University one of the

oldest in Europe in the late 18th

century the city of Bologna was ruled

from papal Rome which meant that the

university was powerful but conservative

in its thinking it was steeped in

traditional Christianity one where God

ruled earth from heaven but that the way

he ran the world was hidden from us mere

mortals we were not meant to understand

him only to serve him and one of the

university's brightest stars was the

anatomist Luigi

Eliseo Galvani but in a neighboring city

a rival electrician was about to take

Galvani to task

this is jávea only a hundred fifty miles

from bologna but by the end of the 18th

century worlds apart politically it was

part of the Austrian Empire which put it

at the very heart of the European

enlightenment liberal in its thinking

politically radical and obsessed with

the new science of electricity it was

also home to Alessandro Volta Alessandro

Volta couldn't have been more unlike

Galvani from an old Lombardi family he

was young arrogant charismatic a real

ladies man and he courted controversy

unlike Galvani he'd like to show off his

experiments on an international stage to

any audience

vaulters ideas were unfettered by

Galvani's religious dogma like Benjamin

Franklin and the European enlightenment

he believed in rationality the

scientific truth like a Greek God would

cast ignorant to the floor superstition

was the enemy reason was the future

 

both men were fascinated by electricity

and both brought their different ways of

seeing the world to bear on it Galvani

had been attracted to the use of

electricity in medical treatments for

instance in 1759 here in Bologna

electricity was used on the muscles of a

paralyzed man one report said it was a

fine sight to see the mastoid rotate the

head the biceps bend the elbow in short

to see the force and vitality of all the

motions occurring in every paralyzed

muscle subjected to the stimulus Galvani

believed these kinds of examples

revealed that the body worked using

animal electricity a fluid that flows

from the brain through the nerves into

the muscles where it's turned into

motion and who devised a series of

grisly experiments to prove it

now he first prepared a frog he writes

the Frog is skinned and disemboweled

only their lower limbs are left join

together containing just the cruel

nerves well I've left my frog mostly

intact but I've exposed the nerves that

connect to the frog's legs then he used

hawks bees electrical machine to

generate the electrostatic charge that

would accumulate and travel along this

arm and out through this copper wire

then he connected the charge carrying

wire to the Frog and another to the

nerve just above the neck let's see what

happens

oh and the frog's leg twitches just as

he makes contact there we go now for

Galvani what was going on there was that

there's a strange special kind of entity

in them in the animal muscle which he

calls animal electricity it's not like

any other electricity its intrinsic to

living beings

but for Volta animal electricity smacked

of superstition and magic it had no

place in rational and enlightened

science Volta saw the experiment

completely differently to Galvani he

believed it reveals something totally

new for him the legs were jumping as a

result of the release of animal

electricity from within them but because

of the artificial electricity from

outside the legs were merely the

indicator

they were only twitching because of the

electricity from the horse be machine

back in Bologna Galvani reacted

furiously to vaulters ideas he believed

Volta had crossed a fundamental line

from electrical experiment into God's

realm and that was tantamount to heresy

to have a kind of spirit like

electricity to have that produced

artificially and to say that that spirit

that living force that agency was the

same that something produced by God that

God had put into a living human body or

a frog's body that seemed sacrilegious

to them because it was eliminating this

boundary between God's realm of the

divine and the mundane realm of the

material

spurred on by his religious indignation

Galvani announced a new series of

experimental results which would prove

that Volta was wrong during one of his

experiments he hung his frogs on an iron

wire and saw something totally

unexpected if he connected a copper wire

to the wire the frog was hanging from

and then touched the other end of the

copper to the nerve it seemed to him

that he could make the frog's leg twitch

without any electricity at all Cavani

came to the conclusion that it must have

been something inside the frog's even if

dead that continued for a while after

death to produce some kind of

electricity and the metal wires was

somehow releasing that electricity over

the next month's Galvani's experiments

focused on isolating this animal

electricity using combinations of frog

and metal Leyden jars and electrical

machines for Galvani these experiments

were proof that the electricity was

originating within the frog itself the

frogs muscles were Leyden jars storing

up the electrical fluid and then

releasing it in a burst on the 30th of

October 1786 he published his findings

in a book de animali electricity of

animal electricity

Galvani was so confident of his ideas he

even sent a copy of his book to Volta

but Volta just couldn't stomach

Galvani's idea of animal electricity he

thought the electricity just had to come

from somewhere else

but where

in the 1790s here at the University of

Pavia almost certainly in this lecture

theater which still bears his name

voltar began his search for the new

source of electricity his suspicions

focused on the metals that Galvani had

used to make his frog's legs twitch his

curiosity had been piqued by an odd

phenomenon that he'd come across how

combinations of metals tasted he found

that if he took two different metal

coins and placed them on the tip of his

tongue and then placed a silver spoon on

top of both he got a kind of tingling

sensation rather like the tingling you'd

get from the discharge of a Leyden jar

Volta concluded that he could taste

electricity and that it must be coming

from the contact between the different

metals in the coins and spoon his theory

flew in the face of Galvani's the frog's

leg switched not because of its own

animal electricity but because it was

reacting for the electricity from the

metals but the electricity his coins

generated was incredibly weak how could

he make it stronger

 

then an idea came to him as he revisited

the scientific papers from the great

British scientist Henry Cavendish and in

particular his famous work on the

electric torpedo fish he went back and

took a closer look at the torpedo fish

and in particular the repeating pattern

of chambers in its back he wondered

whether it was this repeating pattern

that held the key to its powerful

electric shock perhaps each chamber was

like his coins and spoon each generating

a tiny amount of electricity and perhaps

the fish's powerful shock results from

the pattern of chambers repeating over

and over again with growing confidence

in his new ideas Volta decided to fight

back by building his own artificial

version of the torpedo fish so he copied

the torpedo fish by repeating its

pattern but using metal here's what he

did he took a copper metal plate and

then placed above it a piece of card

soaked in dilute acid then above that he

took another metal and placed it on top

while he had here was exactly the same

thing as Galvani's two wires but now

Volta repeated the process what he was

doing here was building a pile of metal

in fact his invention became known as

the pile

but it's what it could do that was the

really incredible revelation Volta then

tried his pile out on himself by getting

two wires and attaching them to each end

of the pile and bringing the other ends

to touch his tongue he could actually

taste the electricity this time it was

more powerful than normal and it was

constant he'd created the first battery

the machine was no longer an electrical

and mechanical machine it was just a

purely electrical machine so he proved

that a machine imitating the fish could

work that what he calls the metal or

contact the electricity of different

methods could work and that he regarded

as his final winning move in the

controversy with Galvani what vaulters

piles showed was that you could develop

all the phenomena of animal electricity

without any animals being present so

from the voltaic point of view it seemed

as if Galvani was wrong there's nothing

special about the electricity in animals

it's electricity and it can be

completely mimicked by this artificial

pile but the biggest surprise for Volta

was that the electricity it generated

was continuous in fact it poured out

like water in a stream and just as in a

stream where the measure of the amount

of water flowing is called a current so

the electricity flowing out of the pile

became known as an electrical current

 

200 years after Volta we finally

understand what electricity actually is

the atoms in metals like all atoms have

electrically charged electrons

surrounding a nucleus but in metals the

atoms share their outer electrons with

each other in a unique way which means

they can move from one atom to the next

 

if those electrons move in the same

direction

at the same time the cumulative effect

is a movement of electric charge this

flow of electrons is what we call an

electric current within weeks of bolts

of publishing details of his pile

scientists were discovering something

incredible about what it could do

its effect on ordinary water was

completely unexpected the constant

stream of electric charge into the water

was ripping it up into its constituent

parts

the gases oxygen and hydrogen

electricity was heralding the dawn of a

new age a new age where electricity

ceased being a mere curiosity and

started being genuinely useful with

constant flowing current electricity new

chemical elements could be isolated with

ease and this laid the foundations for

chemistry physics and modern industry

vaulters pile changed everything

 

the panel made Volta and international

celebrity fate sit by the powerful and

the rich

in recognition a fundamental measure of

electricity was named in his honor the

vault

but his scientific adversary didn't fare

quite so well Luigi Eliseo Galvani died

on the 4th of December 1798 depressed

and in poverty for me though it's not

the invention of the battery that marks

the crucial turning point in the story

of electricity it's what happened next

 

it took place in London's Royal

Institution it was a moment that marked

the end of one era and the beginning of

another

 

it was overseen by Humphrey Davy the

first of a new generation of

electricians young confident and

fascinated by the possibilities of

continuous electrical current

so in 1808 he built the world's largest

battery it filled an entire room

underneath the Royal Institution it had

over 800 individual voltaic piles

attached together

it must have hissed and breathed

sulfurous fumes in a darkened room lit

by centuries-old technology candles and

oil lamps davy connected his battery to

two carbon filaments and brought the

tips together the continuous flow of

electricity from the battery through the

filaments left across the gap giving

rise to a constant and blindingly bright

spark

 

outs of the darkness came the lights

  

Davy's arclights truly symbolizes the

end of one era and the beginning of our

era the era of electricity

 

but there are truly grisly coda to this

story in 1803

Galvani's nephew won Giovanni aldini

came to London with a terrifying new

experiment a convicted murderer called

George Forster had just been hanged in

new gates and when the body was cut down

from the gallows it was brought directly

to the lecture theatre where eldini

started his macabre work using a voltaic

pile he began to apply an electric

current to the dead man's body then

eldini put one electrical conductor in

the dead man's anus and the other at the

top of his spine Foresters limp dead

body

Sat bolt upright and his spine arched

and twisted for a moment it seemed as

though the dead body had been brought

back to life it appears as though

electricity might have the power of

Resurrection and this made a profound

impact on a young writer called Mary

Shelley

Mary Shelley wrote one of the most

powerful and enduring stories ever based

partly here on Lake Como Frankenstein

tells the story of a scientist a Galvin

is probably based on eldini who brings a

monster to life using electricity and

then disgusted by his own arrogance he

abandons his creation just like Davey's

arc lamp this book symbolizes changing

times the end of the era of miracles and

romance and the beginning of the era of

rationality industry and science

and it's that new age we explore in the

next program because at the start of the

19th century scientists realized that

electricity was intimately connected

with another of nature's mysterious

forces magnetism and that realization

would completely transform our world

electricity is one of nature's greatest

forces and by the middle of the 20th

century we'd harnessed its two lights

and power our modern world hundreds of

years of scientific discoveries and

inventions brought us here but it would

take the eccentric genius of one man to

unlock the full potential of electrical

power

in the winter of 1943 nikola tesla

looked towns across the manhattan

skyline for the very last time Tesla had

been born into a world powered by steam

and lit by gas but before his eyes he

saw a new world a world transformed a

world powered by electricity his world

frail lonely and still mourning the

death of one of his beloved pigeons this

extraordinary and eccentric genius knew

that his life's work was done and he lay

back on his bed to die you'll be three

days before anyone found his body

just over 200 years ago early scientists

discovered electricity could be much

more than simply a static charge it

could be made to flow in a continuous

current

 

but they were about to discover

something profound that electricity is

connected to magnetism

harnessing the link between magnetism

and electricity would completely

transform the world and allow us to

generate seemingly limitless amounts of

electrical power

 

this is the story of how scientists and

engineers unlocked the nature of

electricity and then used it in an

extraordinary century of innovation and

invention but not before one of the most

shocking engineering rivalries in

history was finally laid to rest

our story begins in London at the

beginning of the 19th century with a

young man who would further our

understanding of electricity as much as

any other on the 29th of February 1812 a

20 year old self educated book binder

called Michael Faraday came here to the

Royal Institution of Great Britain he

was surrounded by the great and the good

of the academic world and he was about

to listen to one of the greatest

scientific minds of the age Faraday the

son of a blacksmith had finished his

formal education when he was just 12

years old he would never get to

university but he wasn't finished with

learning as he was fascinated by science

Faraday worked long and hard during the

day burning books but in the evenings he

would read whatever scientific

literature he could lay his hands on he

loved learning new things about the

world and he had this constant desire

this passion to understand why things

were the way they were reading

scientific papers was one thing but to

really satisfy his craving for knowledge

Faraday was desperate to see the

experiments themselves and he eventually

got his chance when he was given a

ticket to attend one of the last

lectures of England's greatest chemists

at the time sir Humphrey Davy

it was to change young Faraday's life

forever

after watching Devi or inspired and full

of ideas Faraday knew what he wanted to

do with his life he was determined to

dedicate himself to furthering science

and that's just what he did within a

year Devi had appointed him as an

assistant at the Royal Institution with

Devi as his patron and well his boss

faraday studied all manner of chemistry

but what would inspire his greatest

breakthroughs with the invisible forces

of electricity and magnetism in 1820

both were being studied by a Danish

scientist Hans Christian Oersted

who'd made an extraordinary discovery

he passed electric current through a

copper rod and brought it close to a

magnetic compass needle and saw that it

made the needle rotate to earth stead it

was remarkable he'd shown for the first

time then electric currents can create a

magnetic force

he'd bound electricity and magnetism

together today we call it

electromagnetism and it's one of the

fundamental forces of nature versus

discovery sparked off a whole new Specht

of inventive activity around and about

the fields of electricity you can almost

see electrical experimenters vying

competing with each other to find new

links between electricity and the other

powers of nature at the Royal

Institution Faraday set about recreating

Earth's Ted's work which would mark his

first steps to fame and fortune

and through his rigorous research he

concluded that there must be a flow of

forces acting between the wire and the

compass needle the device he designed to

demonstrate it would change the course

of history

Faraday created a circuit using a

battery like this a pair of wires and a

mercury bath now the circuit carries on

through these copper posts and this wire

hangs freely it dangles into the mercury

now because mercury is such a good

conductor it completes the circuit when

the current runs through the circuit it

generates a circular magnetic force

field around the wire now this interacts

with the magnetism from a permanent

magnet that Faraday had placed in the

middle of the mercury together they

forced the wire to move Faraday had

proved that this invisible force really

does exist

and he could see its effect circular

motion this beautiful device was the

first to convert electric current into

continuous motion basically it's the

earliest ever electric motor the Faraday

was about to take this experiment

further one the lasting effects of

Faraday's discovery of a little

irritations in 1821 was that it showed

that there was a relationship of some

sort between electricity magnetism and

motion Faraday explored this

relationship in detail and set himself

an even more difficult challenge to use

magnetism and motion to make electricity

eventually his obsession hard work and

determination paid off

the breakthrough came on the 17th of

October 1831 when Faraday took a magnet

like this and moved it in and out of a

coil of wire he was able to detect a

tiny electric current in the coil moving

one way and then the other

Faraday knew he was onto something a few

days later instead of moving the magnet

through the conducting wire coil he set

up the equivalent experiment by moving a

conducting copper plate through the

magnetic field he didn't know it at the

time but as his spinning disk cut

through this magnetic field billions of

negatively charged electrons were

deflected from their original circular

course and began to drift towards the

edge a negative charge built up at the

outer edge of the disk leaving a

positive charge at the center and once

the disk was connected to wires the

electrons flowed in a steady stream

Faraday had generated a continuous flow

of electric current unlike a battery his

current flowed for as long as his copper

disc was spun he'd created electrical

power directly from mechanical power

though Faraday's discovery of induction

was extraordinarily important in its own

right and had profound effects for the

understanding of electricity and

technology for the rest of the 19th

century but Faraday what it did was open

a decade of powerful research because it

gave him the clue about how he should

pursue his was Cerf

while Faraday continued his work trying

to understand the very nature of

electricity inventors from across Europe

were less interested in the science and

more interested in how electricity could

make their money what's actually quite

remarkable is certainly from a

contemporary perspective is that by and

large nobody really seems to care very

much what electricity is you don't have

great theoretical debates as to whether

as a force of fluid on a principle or a

power what they're really interested in

is what electricity can do Faraday

living in a world of steam power was

informing the scientific community about

the nature of electricity but at the

same time another breakthrough in how we

could actually use it have been made

this will be the first device that

really brought electricity out of the

laboratory and into the hands of

ordinary people the Telegraph

the key to understanding the Telegraph

is understanding a special kind of

magnets and electromagnets basically a

magnet created by an electric current

the first electromagnets were developed

independently by William sturgeon in

Britain and Joseph Henry in America and

just as Faraday had discovered that by

coiling his wire he could increase the

current in it produced by the moving

magnets so Henry and sturgeon discovered

that by adding more coils in their

currents carrying wires they could make

a more concentrated magnetic field

basically the more coils the more turns

the stronger the magnet so if I pass a

current through this electromagnet you

can actually see the effects of the

magnetic field this is the standard

school experiments of sprinkling iron

filings on top of the magnet I give it a

tap see the iron filings follow the

contours of the field this allows us to

visualize the effects of magnetism to

make an electromagnet even stronger

Henry and sturgeon discovered that they

could place certain kinds of metal

inside the electromagnetic coil the

reason iron is so effective is

fascinating because you can think of it

as being made up of lots of tiny magnets

all pointing in random directions at the

moment this is not a magnet the tiny

magnets inside are aligned similarly to

these compass needles if you see they're

all pointing in different directions but

when you apply a magnetic field they all

align together they all combine these

magnets and cumulatively they add to the

strength of the electromagnet so what

Henry and sturgeon did was place two

electromagnetic coils on each arm of

their horseshoe to create something it

was many many times more power

and we can see the power of this

horseshoe electromagnet if I turn it on

and use something slightly bigger than

iron filings these small pieces of iron

the strength of the magnetic field

holding them in place what's important

to remember of course is that this

electromagnet only works all the time

there's a current passing through it as

soon as I turn off the current the

magnetism disappears early experimenters

showed off this power by lifting metal

weights Henry even made one big enough

to lift a ton and a half of metal

impressive but not world-changing but

place that magnet much further away at

the end of a wire and suddenly you can

make something happen at your command in

an instant this ability to control a

magnet at a distance is one of the most

useful things we've ever discovered if

electricity can be made visible a long

way away from the original source of

power then you've got a source of

instantaneous communication

by the middle of the 1840s Samuel Morse

had developed a messaging system based

on how long an electrical circuit was

switched on or off a long pulse of

currents for a - a short burst for a dot

this allowed messages to be sent and

received by using a simple code

contemporary early Victorian

commentators reflect on the fact that

electricity on a telegraph is literally

making their world a smaller place you

very often get a sort of rhetoric

throughout the 19th century when people

are talking about the telegraph about

how more communication more

understanding will render war obsolete

because we all understand each other

better

I mean retrospectively it seems

hopelessly utopian by the 1850s Europe

and America were criss crossed with

land-based telegraph wires but the dream

of instant global communication was

frustratingly out of reach this was

because there was still no cable capable

of carrying messages between two of the

greatest powers on earth Britain and

America many experts were convinced that

a working Atlantic cable was impossible

but those who disagreed knew that if

they could solve this problem it could

make them serious money and in the 1850s

American businessman and British

engineers joined forces to prove this

could be done

attempt after attempts ended in disaster

the heavy cables kept snapping in heavy

seas and storms

finally on the 29th of July 1858 two

parts of a cable were spliced together

in mid-atlantic you see a single cable

was simply too big to have been carried

by one ship then one end was taken to

Newfoundland and the other end to

Southwest Ireland six days later the

first direct link between the two most

powerful nations in the world was in

place the project was hailed a huge

success and a formal message of

congratulations was sent from Queen

Victoria to President Buchanan but

before the celebrations were over things

started to go very wrong

this is chief engineer brights original

notebook you can see here Queen

Victoria's original message now it's

only 98 words long but it took 16 hours

to transmit the telegraph operators on

the other side found it very hard to

decipher the message the electrical

signals that they were receiving were

blurred and distorted and they kept

asking for words to be repeated over and

over again so you can see here repeat

after sending waiting to receive no

signals clearly transmitting across the

Atlantic wasn't going to be as

straightforward as people had hoped over

the next few days several hundred

messages were exchanged

but those arriving in Newfoundland

became almost impossible to decipher

just a jumbled mess of dots and dashes

there was a serious problem with the

cable and it was getting worse while the

1858 cable was never fully repaired and

the end finally came when British

engineer Wildmon Whitehouse mistakenly

believed that by increasing the signal

voltage he could force the messages

through to Newfoundland the cable simply

stopped working altogether

 

at the time increasing the voltage by

using more powerful batteries made sense

most experts believed electric current

flowed through a cable like a fluid in a

pipe increasing the voltage was the

equivalent of increasing the pressure in

the system forcing the current through

to the other end

but the Telegraph was actually carrying

pulses or ripples of currents along the

cable not a continuous stream and over

long distances these pulses were

becoming distorted making it difficult

to tell what was a short dot and which

was a longer - by studying the

effectiveness of underwater cabling

scientists were beginning to understand

that electric current didn't always flow

like water but was also creating

invisible electromagnetic waves or

ripples and it's this breakthrough that

would lead to a new branch of research

into the electromagnetic spectrum and

solve the problems of the Atlantic

Telegraph in effect the transatlantic

cable was a giant ambitious hugely

expensive experiment the failure of

science to keep pace with technology

have been exposed and a new more

theoretical and for me much more

exciting approach to understanding

electricity began to unfold

armed with this new understanding of how

electric pulses actually moved along the

cable improvements were made to its

composition design and how it was laid

it would take another eight years of

scientists and engineers working

together before a working cable was

finally put in place and on Friday the

27th of July 1866 a message was sent

from Ireland to Newfoundland clear and

crisp

the Treaty of peace has been signed

between Austria and Prussia at last the

dream of instant transatlantic

communication had become a reality the

success of the 1866 cable makes the

world a smaller place yet again

a change for the world in where it took

days or weeks or months for information

to travel to a world in which

information two seconds or minutes to

travel now is far more profound I think

than anything that's taken place to in

my lifetime

the invention of the Telegraph changed

ordinary people's lives but it will be

the breakthroughs in how we used

continuously flowing electric currents

they would have an even greater impact

because inventors were developing a new

way of using electricity to make

something every person in the world

would want electric light

until the 19th century we only knew of

one way to make our own light burn

things and by the middle of the 19th

century we've perfected a very effective

way of lighting our homes using gas

 

a typical British home in the 1860s

would have been lit like this highly

flammable gas would have been pumped

directly into people's houses through a

network of pipes but these gas lamps

were too dull for large outdoor areas so

railway stations and streets began to be

lit from a more powerful source electric

arc lights the first arc lights were

demonstrated by Michael Faraday's mentor

Sir Humphrey Davy at the Royal

Institution as early as 1808 and they

worked by passing a continuous spark of

electricity across two carbon rods but

their intense white glow was just too

bright for people's homes for an

electric light to compete with gas it

would need to be subdivided into many

smaller less powerful and more gentle

lamps whoever succeeded in bringing

electric lights to every home in the

land was guaranteed fame and fortune and

by the early 1880s the most famous most

prodigious most fiercely competitive

inventor in the world had taken on the

challenge the American Thomas Alva

Edison Bert Edison invention was a

passion it's what he loved doing he

loved being in the laboratory the first

thing that drove that passion is that it

was a lot of fun for Edison I think that

was the thing that he found most

exciting is that this was something he

did well and it allowed all of his

creativity to come to the floor Edison

is mr. electrical invention

he's the man they trust he's the man

that they think can do anything he's

also the man who has his carefully

cultivated connections with

entrepreneurs where people are willing

to put you put their cash where Edison's

mouth is so to speak and back in in the

sort of venture for Edison the money was

probably the least important reason for

Edison the money was important for one

reason to allow him to do the next

project

Edison had assembled a group of young

and talented engineers at a cutting-edge

laboratory in New Jersey 26 miles from

Manhattan Menlo Park would become the

world's first research and development

facility allowing Edison's team to

invent on an industrial scale

they worked incredible hours you know

one of them talked about how he ever

hardly ever saw his children because he

was in the lab all the time

 

but they knew they were in the midst of

something really important right that if

Edison succeeded right if they succeeded

with Edison that their futures were

secure

 

Edison's dream was to bring electric

lights to every home in the land and

with his team of engineers behind him

and the vision of an electric future

ahead he launched his campaign the race

to bring electric light to the world was

to play out in the great cities of the

time New York Paris London

Edison's Menlo Park team set about

developing a totally different form of

electric lamp the incandescent light

bulb in fact Edison's light bulb design

wasn't all that new or unique French

Russian Belgian and British inventors

have been perfecting similar bulbs for

over 40 years and one of them an

Englishman

Joseph Swan had been developing his own

version of an incandescent lamp both

Swan and Edison's light bulbs work by

passing an electric current through a

filament now a filament is a material in

which the electric current flows through

with more difficulty than it does

through the copper wire in the rest of

the circuit and it relies on the idea of

resistance now inside this jar I have a

filament made out of ordinary pencil lit

and we can see what happens as I pass a

current through it down at the atomic

scale the atoms in the filament impede

the flow of electricity so it takes more

energy to force it through and this

energy is deposited in the filament as

heat now as it heats up it's resistance

goes up which again raises its

temperature until it glows white hot

now one of the first materials Edison

used for his filaments was platinum with

its relatively high melting point

platinum could be heated to a white-hot

temperature without melting it could

also be stretched into thin strands and

the thinner the Strand the more

resistance it offered to the current

passing through it but platinum was

expensive and didn't offer enough

resistance the race was on to find a

better alternative and the solution came

when the Menlo Park team switched to a

method Swan was also developing using a

vacuum to stop Cheaper carbon filaments

from burning up too quickly

Edison and Swan tested all kinds of

different materials for their filaments

everything from raw silk and parchments

to cork edison even tested his engineers

beard hair eventually he settled on

bamboo fiber while Swan used a treated

cotton thread Edison and swans light

bulb designs were very similar

eventually they came to an agreement and

went into partnership to sell light

bulbs in the UK today many people still

believe that Edison alone invented the

light bulb while Swan has become a

footnote in history

but his incandescent bulb was only part

of Edison's strategy he'd also invented

an entire electrical system of sockets

cables and meters to go with it and

being a brilliant businessman he

developed a groundbreaking new way of

distributing electricity Edison knew

that the key to making money from his

system was to generate the electricity

in a Central Station and then sell it to

as many customers as possible it seems

obvious to us now but until then anyone

who wanted to use electricity had to

have their own noisy generator to make

it

Edison's ambition was huge he wanted to

light the fastest-growing and most

exciting city in the world

New York in the summer of 1882 Edison

stood in a unique position at the center

of 19th century science and invention

he'd patented a cutting-edge

incandescent light bulb

he'd amassed an unprecedented knowledge

of electrical engineering and above all

he'd cultivated a reputation among the

American public of being such a genius

inventor that journalists hung on his

every word and the financial muscle of

Wall Street was quick to throw itself

behind his new ideas his vision to

electrify Manhattan and then of course

the rest of the world was seemingly

within his grasp because Edison and his

team were about to launch their most

expensive and risky project yet

America's first power station generating

continuous direct current just before 3

p.m. on the 4th of September 1880 -

Thomas Edison surrounded by a gaggle of

bankers dignitaries and reporters

entered JP Morgan's building right

behind me

flicked one of the Edison patented

switches and 100 of his incandescent

bulbs began to glow turning to a nearby

journalist he said I have accomplished

all that I promised

half a mile away on Pearl Street

Edison's new power station costing half

a million dollars and four years of hard

work had sprung into life the currents

surged through buried cables stretching

out in each direction of course it might

seem obvious to us now but in New York

back in the early 1880s the idea of

burying electric cables underground

seemed like an unnecessary expense this

street would have been criss crossed

with hundreds of cables used for

Telegraph's telephones and arc street

lighting looking up you'd have seen a

tangled mass of black spaghetti blocking

out the light Edison knew this dangerous

situation had to change and for him to

make as much money as he could

electricity needed rebranding it had to

be considered safe so Edison is arguing

both for the greater safety of his DC

low voltage system and 400 round lines

he can argue that he has a much safer

system than electric arc light for

streets or gas lighting for indoor

lighting he doesn't have to worry about

fires doesn't have to worry about

electrocution that all of this is much

safer because of the system he's created

with this underground system burying

every cable was not only very expensive

but was a logistical nightmare because

this was one of the busiest square miles

in the world

Edinson chose this area for a reason

Wall Street's rich important influential

because for Edison's system to make

money all these wealthy customers had to

be within a mile of his power station

and this was because Edison calculated

the thickest cable he could afford would

only carry an adequate amount of his

continuous direct current to customers

within this range this was a huge leap

forward because for the first time

dozens of customers could be supplied by

just one power station but there was a

big problem

Edison's Network could never be

economical in lighting America's new

suburbs they just didn't have the

concentration of customers needed to

make building these expensive power

stations worthwhile how do we stuck with

Edison's way of generating and

distributing electricity the world would

be a very different place we'd have to

have power stations scattered around no

more than a mile apart even in the

centers of our towns or cities and it

will be extraordinary expensive to even

provide power for smaller communities

but someone who held the answers to

these problems was about to enter the

story someone who would help create the

modern world and who'd play an integral

part in one of the biggest fallouts

in scientific history his name was

Nikola Tesla and he was right under

Edison's nose

Nikola Tesla was a Serbian inventor who

was born in Croatia and who worked for

Edison briefly after arriving in New

York at the age of 28 European

introverted a deep thinker he was

everything Edison wasn't Edison and

Tesla could not be more different in the

way that they handled herself appearance

and their and their manners and the way

that they constructed a public image for

themselves Edison could care less about

the clothes that he had on and if he

spilled chemicals on his good Sunday

suit then he spilled chemicals on his

good Sunday suit he he was you know

basically the very various kind of slob

'only guy Tesla on the other hand even

as a young man in his mid-20s is

thinking about his appearance how he

comes across the people she cares about

his clothes he cares about his manner

indeed he even cares about how is how

his photograph his portraits are taken

and he always wants to make sure that he

has a nice three-quarter profile so you

don't see that the fact that he has a

bit of a pointy chin the life and death

of Nikola Tesla is one of the most

fascinating yet tragic stories of

scientific brilliance cutthroat business

and shocking public relations stunts the

American public may have been wowed by

Edison's new direct current power

stations but Tesla was less impressed he

had a dream electricity could be

transmitted across entire cities or even

nations and he believed he knew how it

could be done by using a different type

of electric current

Electrical experts know that the smaller

the current sent down a cable the

smaller the losses in it through

resistance and so the longer the cable

could be Tesla proposed using a method

of transmitting electricity where the

currents could be lowered without a fall

in the amount of electrical power at the

other end it was called alternating

current alternating current is exactly

there it's electric current that

alternates between moving in one

direction then the opposite direction

very quickly as opposed to a direct

current which moves only in one

direction Tesla was interested in

alternating current because like other

electrical engineers in the late 1880s

he realized that as you raise the

voltage of any current that you transmit

from point A to point B is going to be

more efficient to have a higher voltage

and since the amount of electric power

in a cable is its voltage multiplied by

its current increasing the voltage meant

the current in the cables could be

reduced and so losses due to resistance

will be less however you don't want very

high voltages on the order of say 20,000

volts coming into your home so you need

to step down the current that is being

transmitted over distance into your home

and to do that you need a converter or a

transformer

alternating current allows you to use a

transformer to make that switch from the

high transmission voltage to the lower

voltage that you're going to use at

consumption

 

perfecting the technology to transmit

electricity hundreds of miles from where

it was generated would mark a huge step

towards the modern world and a wealthy

industrial and tripping or was already

developing the solution his name was

George Westinghouse Westinghouse

believed alternating currents was the

future but it had a big drawback while

it was fine for electric light unlike

direct current

there was no practical motor that could

run on it and no one believed there ever

would be apart from Nikola Tesla Tesla

as an inventor liked to say that the

first thing you need to do is not to

build something but to imagine it to

think it through to plant it and he had

what modern-day psychologists would call

an eidetic memory he could basically

remember everything that he saw and then

visualize it in three dimensions and

they often say that the people would

have this skill see it about an arm's

length away out here and they see it in

three dimensions in that space and all

the indications are is this is Tesla had

that ability this is a Tesla egg it's a

replica of the one Tesla used to

demonstrate his greatest breakthrough

and one of the most important inventions

of all time it showed how rotary

movements can be produced directly from

an alternating current crucially one

that could be generated thousands of

miles away this was something that had

never been done before

 

when Tesla was working on the

alternating current motor he was

thinking big and he was not just

tinkering with one little component of

the motor and saying gee if I can make

that a little bit better it will work

out he's actually thinking about an

entire system that involves the

generator the wires to the motor and the

motor itself he's a complete maverick

he's thinking outside the box he's doing

things very differently than any of his

fellow contemporary inventors Tesla's

solution was ingenious he fed more than

one alternating current into his motor

and timed them so that they followed in

sequence with each other the first

alternating current energized a coil of

wire inside the motor creating an

electromagnetic field which attracted

the motorists central moving part to it

and then faded the second overlapping

current fed the next coil dragging the

movie part around further before it

faded and the same for the third coil

and the fourth the result was a

revolving magnetic field strong enough

to make the motor or in this case his

egg spin Tesla designed an entire

electrical system around this called

polyphase transmission this meant a

noisy and smelly power station

generating lots of useful alternating

current could now be situated away from

populated areas

and for the first time you can build

large power stations wherever you want

on the edge of town or a waterfall like

Niagara and you can then distribute the

power over long distances and serve all

the people in a major city or or

metropolitan center Tesla's breakthrough

was the last piece of the jigsaw but he

still had to convince the world that his

solution was better than the direct

current method championed by Edison

Edison continued to roll out his direct

current system building power stations

across New York State the then Tesla met

George Westinghouse the man who could

make his dreams into a reality in July

1888 Westinghouse made an offer for

Tesla's patents which has become part of

the mystery and folklore surrounding the

whole Nikola Tesla story and where it's

difficult to separate fact from fiction

Tesla was paid seventy five thousand

dollars for his alternating current

patents and offered two dollars 50 for

every horsepower his motors would

generate this should have guaranteed him

vast wealth for the rest of his life but

that isn't what happened it's clear to

us now that at the time the a/c system

was a much better method of transmitting

electric power and you'd think that with

Tesla's breakthroughs nothing could

stand in the way of the success of AC /

DC but one man still believed totally in

his direct current inventions from the

filaments of the bulbs to the switches

sockets and generators and he wasn't

about to waste millions of dollars on

changing them

Edinson the battle lines were drawn

Westinghouse and Tesla went toe-to-toe

with Edison for New York's lucrative

lighting contracts two completely

different systems battling it out for

one ultimate prize the chance to light

up America and then the world it will

become known as the War of the currents

both camps tried to undercut each other

on cost but Edison believed his beloved

direct currents was better than

alternating current because it was safer

touching an Edison cable with its low

voltage was painful but relatively

harmless

whereas alternating current cables

carried a much higher voltage and

touching them could be deadly

so what Aaron was trying to do was to

again define his DC system right as the

safe system it's better than Electric

Street park lights it's better than gas

and it's now better than high-voltage AC

incandescent light it's the system

that's safe you adopt the Edison system

you can be sure it's gonna be safe

Edison claimed that AC was a more

dangerous type of current than DC and he

highlighted every accident to

Westinghouse his workmen and every fire

caused by short circuits

it was a potent message because in the

1880s many people were still terrified

by electricity it could shock and even

kill in an instant and the reasons why

still weren't free understood for many

the idea of piping this invisible killer

into their homes was utterly ludicrous

so the weapon used in the War of the

currents was fear and a little-known

electrical engineer Harold P Brown was

about to take the fight against AC to a

whole new level it was to prove one of

the most extreme and negative publicity

campaigns in history Brown had devised a

unique and theatrical way of

demonstrating the deadly power of AC and

it was eager to share it with the world

so on a warm summer's evening in July

1888 he gathered together 75 of the

country's top electrical engineers and

reporters to witness a spectacle they

would never forget

 

Brown's plan was extremely macabre he'd

paid a team of street urchins to collect

together stray dogs roaming Manhattan

out on stage he addressed his audience I

have asked you here gentlemen to witness

the experimental application of

electricity to a number of brutes his

demonstration involved electrocuting the

dogs with DC and AC power in an attempt

to show that AC current killed them more

quickly and it wasn't just dogs Brown

went on to make public spectacles of

killing a calf and even a horse and he

moved from dogs to larger animals for a

reason he wanted to show that the AC

form of electricity was so dangerous it

could kill any large mammal including

humans

 

Brown's animal experiments had persuaded

American politicians the most humane

method of executing condemned criminals

should be with alternating current

generated by westinghouse machines

Edison's lawyers even suggested a new

term to describe being electrocuted in

this way to be Westinghouse and of

precisely 6:30 to on the morning of the

6th of August 1890 a 45 year old man

William Kemmler was strapped to a wooden

chair and to soaking wet electrodes were

carefully attached to him and as 26

officials and doctors looked on from an

adjoining room Kemmler said goodbye to

the prison chaplain and waited the

execution of William Kemmler marked the

lowest point in the war of the currents

but it wouldn't quite mark the end

because Nikola Tesla was about to do

something that has never been seen

before something so wondrous and daring

that it would live on forever in the

memories of those who saw

 

  

 

 

Tesla had been developing a method of

generating very high-frequency

alternating currents and on May 21st

1891 at a meeting of top electrical

engineers he demonstrated it

 

  

in an almost magical display of awesome

power and Wonder and without wearing any

safety chain maille of last pins of

thousands of volts produced by a Tesla

coil passed across his body and through

the end of a lab that he was holding

Tesla's alternating current was at such

a high frequency that it passed through

his body without causing serious harm or

even pain this demonstrations showed

that it handled correctly alternating

currents at extremely high voltages

could be safe the War of the currents

had been won by Westinghouse and Tesla

in 1896 the new power station was

completed at Niagara Falls using

Westinghouse AC generators to produce

Tesla's polyphase carriages finally huge

amounts of power could be transmitted

from the Falls to nearby Buffalo and

then a few years later the Niagara plant

was providing power to New York City

itself and today almost all of the

electricity generated in the world is

done so using Tesla's system

but Tesla story doesn't end in fame and

fortune although he went on to make

significant contributions to many other

areas of science and invention to save

George Westinghouse from ruin

after a stock market crash he gave up

his claim to the royalties from his

polyphase inventions Nikola Tesla was a

uniquely talented man and we owe him so

much but it was also hugely complicated

and sadly later in life he became more

and more troubled he was fixated with

the number three counting out loud as he

walked and he developed strange phobias

with germs and with women wearing pearl

jewelry in many ways his brilliant mind

simply spun out of control as Tesla's

life unraveled he withdrew from people

and found emotional comfort elsewhere he

became obsessed with pigeons and was

regularly seen feeding them here in

Bryant Park in the center of Manhattan

he even fell in love with one

particularly unusual white bird and when

it died he was left heartbroken

as an old man Tesla was left almost

bankrupt and alone living as a semi

recluse in this hotel

his last years were spent here in room

three three to seven of The New Yorker

Hotel sad confused destitute

Edison went on to become an American

hero and his company would form part of

General Electric even today one of the

world's biggest multinational

corporations in January 1943 the story

of Nikola Tesla was coming to an end but

looking out across the Manhattan skyline

for the very last time he saw a sky lit

up with twinkling lights and a million

lives transformed by his genius

 

the ability to generate and transmit

electricity and the invention of

machines to use it have changed our

world in ways we couldn't possibly have

imagined we can now generates billions

of watts of electricity every second

every hour every day and whether we do

it using coal gas or nuclear fission

power stations all rely on the

principles discovered and developed by

Michael Faraday Nikola Tesla and all the

other early electrical engineers from an

amazing age of invention we now take

electricity for granted and have

forgotten how magical and mysterious a

force it once was but there's something

we should never forget today without it

the modern world would collapse around

us and our lives would be very very

different

 

in the next episode we tell of the

electrical revelations that led to a

revolution in our understanding of this

amazing force

 

on the 14th of august 1894 an excited

crowd gathered outside

Oxford's Natural History Museum this

huge Gothic building was hosting the

annual meeting of the British

Association for the Advancement of

science over two thousand tickets had

been sold in advance and the museum was

already packed waiting for the next talk

to be given by Professor Oliver Lodge

his name might not be familiar to us now

but his discoveries should have made him

as famous as some of the other great

Electrical pioneers of history people

like Benjamin Franklin Alessandro Volta

or even the great Michael Faraday

quite unwittingly he would set in motion

a series of events that would

revolutionize the Victorian world of

brass and telegraph wire this lecture

would mark the birth of the modern

electrical world a world dominated by

silicon and mass wireless communication

 

in this program we discover how

electricity connected the world together

through broadcasting computer networks

and how we finally learned to unravel

and exploit electricity at an atomic

level

 

after centuries of man's experiments

with electricity a new age of real

understanding was now dawning

 

these tubes are not plugged into any

power source but they still light up its

electricity's invisible effect an effect

not just confined to the wires it flows

through in the middle of the 19th

century a great theory was proposed to

explain how this could be the theory

says that surrounding any electric

charge and there's a lot of electricity

flowing above my head is a force field

these fluorescent tubes are lit purely

because they're under the influence of

the force field from the power cables

above

the theory that a flow of electricity

could in some way create an invisible

force field was originally proposed by

Michael Faraday but it would take a

brilliant young Scotsman called James

Clark Maxwell who would prove Faraday

correct and not through experimentation

but through mathematics

 

this was all a far cry from the typical

19th century way of understanding how

the world works which was essentially to

see it as a physical machine

  

 

before Maxwell scientists had often

built strange machines or devised

wondrous experiments to create and

measure electricity but Maxwell was

different he was interested in the

numbers and his new theory not only

revealed electricity's invisible force

field but how it could be manipulated it

would prove to be one of the most

important scientific discoveries of all

time Maxwell was a mathematician and a

great one and he saw electricity and

magnetism in an entirely new way he

expressed it all in terms of a very

compact mathematical equations and the

most important thing is that in

Maxwell's equations is an understanding

of electricity and magnetism as

something linked and as something that

can occur in waves

 

Maxwell's calculations showed how these

fields could be disturbed

rather like touching the surface of

water with your finger changing the

direction of the electric current would

create a ripple or wave through these

electric and magnetic fields and

constantly changing the direction of the

flow of the currents forwards and

backwards like an alternating current

would produce a whole series of waves

waves that would carry energy Maxwell's

maths was telling him that changing

electric currents would be constantly

sending out great waves of energy into

their surroundings waves that would

carry on forever unless something absorb

them

Maxwell's maths was so advanced and

complicated that only a handful of

people understood it at the time and

although his work was still only a

theory it inspired a young German

physicist called Heinrich Hertz Hertz

decided to dedicate himself to designing

an experiment to prove that Maxwell's

waves really existed and here it is this

is Hertz his original apparatus and his

beauty is in its sheer simplicity he

generates an alternating current that

runs along these metal rods with a spark

that jumps across the gap between these

two spheres now if Maxwell was right

then this alternating current should

generate an invisible electromagnetic

wave that spreads out into the

surroundings if you place a wire in the

path of that wave then at the wire there

should be a changing electromagnetic

field which should induce an electric

current in the wire so what Hertz did

was build this ring of wire his receiver

that he could carry around in different

positions in the room to see if he could

detect the presence of the wave and the

way he did that was leave a very tiny

gap in the wire across which a spark

would jump if a current runs through the

ring now because the current is so weak

that spark is very very faint and Hertz

spent pretty much most of 1887 in a

darkened room staring intensely through

a lens to see if he could detect the

presence of this faint spark

but Hertz wasn't alone in trying to

create Maxwell's waves

back in England a young physics

professor called Oliver Lodge had been

fascinated by the topic for years but

hadn't had the time to design any

experiments to try to discover them then

one day in early 1888 while setting up

an experiment on lightning protection he

noticed something unusual lodged noticed

that when he set up his equipment and

sent an alternating current around the

wires he could see glowing patches

between the wires and with applets

working he saw these glowing patches

formed a pattern the blue glow an

electrical sparks occurred in distinct

patches evenly spaced along the wires he

realized they were the peaks and troughs

of a wave an invisible electromagnetic

wave Lodge had proved that Maxwell was

right finally by accident Lodge had

created Maxwell's electromagnetic waves

around the wires the big question had

been answered

 

filled with excitement at his discovery

large prepared to announce it to the

world that summers and your scientific

meeting run by the British Association

before it though he decided to go on

holiday his timing couldn't have been

worse

because back in Germany and at exactly

the same time Heinrich Hertz was also

testing Maxwell's theories eventually

Hertz found what he was looking for a

minut spark and as he carried his

receiver around different positions in

the room he was able to map out the

shape of the waves being produced by his

apparatus and he checked each of

Maxwell's calculations carefully and

tested them experimentally it was a tour

de force of experimental science back in

Britain as the crowds gathered for the

British Association meeting Oliver Lodge

returned from holiday relaxed and full

of anticipation

 

this Lodge thought would be his moment

of triumph when he could announce his

discovery of Maxwell's waves his great

friend the mathematician Fitzgerald was

due to give the opening address in the

meeting but in it he proclaimed that

Heinrich Hertz had just published

astounding results he had detected

Maxwell's waves traveling through space

we have snatched the Thunderbolt from

Jove himself and enslaved the

all-pervading ether he announced well I

can only imagine how Lodge must have

felt having his Thunder stolen professor

Oliver Lodge had lost his moment of

triumph pipped at the post by Heinrich

Hertz heard a spectacular demonstration

of electromagnetic waves what we now

call radio waves even though he didn't

know it at the time is going to lead to

a whole revolution in communications

over the next century

 

Maxwell's theory had shown how electric

charges could create a force field

around them and that waves could spread

through these fields like ripples on a

pond and Hertz had built a device that

could actually create and detect the

waves as they passed through the air but

almost immediately there would be

another revelation in our understanding

of electricity a revelation that would

once again involve professor Oliver

Lodge and once again his Thunder would

be stolen the story stands in Oxford in

the summer of 1894 Hertz had died

suddenly earlier that year and so large

prepared a memorial lecture with a

demonstration that would bring the idea

of waves to a wider audience Lodge had

worked on his lecture he'd researched

better ways of detecting the waves and

he'd borrowed new apparatus from friends

he'd made some significant advances in

the technology designed to detect the

waves this bit of apparatus generates an

alternating current and a spark across

this gap the alternating current sends

out an electromagnetic wave just as

Maxwell predicted that is picked up by

the receiver it sets off a very weak

electric current through these two

antennae now this is what Hertz had done

larges improvements on this was to set

up this tube full of iron filings the

weak electric current passes through the

filings forcing them to clump together

and when they do they close a second

electric circuit and set off the Bell so

if I push the button on this end

it sets off the bell at the receiver and

it's doing that with no connections

between the two it's like magic you

could imagine a packed house lots of

people in the audience and what they

suddenly see is as if by magic a bell

ringing is quite incredible it might not

have been the most dramatic

demonstration the audience had ever seen

but it certainly still created a

sensation among the crowd logis

apparatus laid out like this no longer

looked like a scientific experiment in

fact it looked remarkably like those

telegraph machines that had

revolutionized communication but without

those long cables stretching between the

sending and receiving stations to the

more worldly and savvy members of the

audience this was clearly more than

showing the maestro Maxwell was right

this was a revolutionary new form of

communication Lodge publishes lecture

notes on how electromagnetic waves could

be sent and received using his new

improvements all around the world

inventors amateur enthusiasts and

scientists read lodges reports with

excitement and began experimenting with

Hertzian waves

 

to utterly different characters were to

be inspired by it

both would bring improvements to the

wireless Telegraph

and both will be remembered for their

contribution to science and far more

than Oliver Lodge

the first was ghoulia mo Marconi Marconi

was a very intelligent astute and a very

charming individual he definitely had

the Italian Irish charm he could apply

this to almost anyone from sort of young

ladies to world-renowned scientists

Marconi was no scientist but he read all

he could of other people's work in order

to put together his own wireless

Telegraph system and it's possible that

because he was brought up in Bologna and

it was fairly close to the Italian coast

that he saw the potential of wireless

communications in relation to maritime

usage fairly early on then aged only 22

he came to London with his Irish mother

to market it the other person inspired

by lodges lecture was a teacher at the

Presidency College in Calcutta called

Jagadish Chandra Bose despite degrees

from London and Cambridge the

appointment of an Indian as a scientist

in Calcutta have been a battle against

racial prejudice

Indians it was said didn't have the

requisite temperament for exact science

well Bose was determined to prove this

wrong and here in the archives we can

see just how fast he's set to work this

is a report of the 66th meeting of the

British Association and Liverpool

September 1896 and here is Bose the

first Indian ever to present at the

Association meeting talking about his

work and demonstrating his apparatus he

built and improved on the detector that

Lodge described because in the hot

sticky Indian climates he'd found that

the metal filings inside the tube that

that Lodge used to do to detect the

waves became rusty and stuck together so

Bose had to build a more practical

detector using a coiled wire instead his

work was described as a sensation the

detector was extremely reliable and

could work on board ships so had great

potential for the vast British naval

fleet Britain was the center of a vast

telecommunications network which

stretched almost around the world which

was used to support an equally vast

maritime network of merchant and naval

vessels which were used to support the

British Empire but Bose a pure scientist

wasn't interested in the commercial

potential of wireless signals

unlike Marconi this was a sort of a new

cutting-edge field but Marconi wasn't a

trained scientist so did come things in

a fairly different way which is made may

have been why he progressed so quickly

in the first place and he was very good

at forming connections with the people

that he needed to form connections with

to enable his work to be done

Marconi used his connections to go

straight to the only place that had the

resources to help him the British post

office was a hugely powerful institution

when Marconi first arrived in London in

1896 these buildings were newly

completed and already moving with

business from the Empire's postal and

telegraph eServices Marconi had brought

his Telegraph system with him from Italy

claiming it could send wireless signals

over unheard-of distances and the post

office engineer in chief William priest

immediately saw the technology's

potential

so priests offered Marconi the great

financial and engineering resources of

the post office and they started work up

on the roof the old headquarters of the

post office were right there and between

this roof and that one Marconi and the

post office engineers would practice

sending and receiving electromagnetic

waves

the engineers helped him improve his

apparatus and then priests and Marconi

together demonstrated it to influential

people in government and the Navy

what priests didn't realize was that

even as he was proudly announcing

Marconi's successful partnership with

the post office Marconi who was making

plans behind the scenes he'd applied for

a British patent on the whole field of

wireless telegraphy and was planning on

setting up his own company when the

patent was granted all hell broke loose

in the scientific community

that patent was itself revolutionary you

see patents could only be taken out of

things that weren't public knowledge but

Marconi famously had hidden his

equipment in a secret box and here it is

when his patent was finally granted

Marconi ceremoniously opened the box

everyone was keen to see what inventions

lay within batteries forming a circuit

iron filings in the tube to complete the

circuit to ring the bell on top nothing

they hadn't seen before and yet Marconi

had patented the lot

the reason why Marconi is famous it's

not because of that invention he doesn't

invent radio right but he improves it

and turns it into a system Lodge doesn't

do that and that's why remember Marconi

and that's why we don't remember Lodge

 

the scientific world was up in arms here

was this young man who knew very little

about the science behind his equipment

about to make his fortune from their

work even his great supporter priests

was disappointed and hurt when he found

out that Marconi was about to go it

alone and set up his own company Lodge

and other scientists began a frenzy of

patenting every tiny detail and

improvement they made to their equipment

this new atmosphere shocked Bose when he

returned to Britain Bose wrote home to

India in disgust of what he found in

England money money money

all the time what a devouring greed I

wish you could see the craze for money

of the people here his disillusionment

with the changes he saw in the country

he revered for its scientific integrity

and an excellence is palpable eventually

though it was his friends who convinced

Bose to take out his one and only patent

on his discovery of a new kind of

detector for waves it was this discovery

that would lead to perhaps an even

greater revolution for the world he had

discovered the power of crystals

this were places older techniques using

iron filings which are messy and

difficult and don't work well and here's

a whole new way of detecting radio waves

and it's one that's going to be at the

center of a radio industry BOCES

discovery was simple but it would truly

shape the modern world when some

crystals are touched with metal to test

their electrical conductivity they can

show rather odd and very behavior take

this crystal for example if I can touch

us in exactly the right spot with the

tip of this metal wire and then hook it

up to a battery it gives quite a

significant current but if I switch

around my connections to the battery and

try and pass the current through in the

opposite direction it's a lot less it's

not a full conductor of electricity

it's a semiconductor and it found its

first use in detecting electromagnetic

waves when boasts used a crystal like

this in his circuits instead of the

tuber filings he found it was a much

more efficient and effective detector of

electromagnetic waves it was this

strange property of the junction between

the wire known as the cat's whisker and

the crystal which allowed current to

pass much more easily in one direction

than the other that meant it could be

used to extract a signal from

electromagnetic waves

at the time no one had any idea why

certain crystals acted in this way but

two scientists and engineers the strange

behavior had a profound an almost

miraculous practical effect with

crystals as detectors now it was

possible to broadcast and detect the

actual sound of a human voice or music

in his Oxford lecture in 1894 Oliver

Lodge had opened a Pandora's box as an

academic he'd failed to foresee that the

scientific discoveries he'd been such a

part of had such commercial potential

the one Paton he had managed to secure

the crucial means of tuning a receiver

to a particular radio signal was bought

off him by Marconi's powerful company

perhaps the worst indignation for lodge

though would come in 1909 when Marconi

was awarded the Nobel Prize in Physics

for wireless communication it's

difficult to imagine a bigger snub to

the physicist who's so narrowly missed

out to Hertz in the discovery of radio

waves and who'd then go on to show the

world how they could be sent and

received

but despite the snub Lodge remained

magnanimous using the new broadcasting

technology that resulted from his work

to give credit to others as this rare

film of him shows pets made a great

advance he discovered how to produce and

detect waves in space thus bringing the

ether into practical use

harnessing x' harnessing is for the

transmission of intelligence in a way

which has subsequently been elaborated

by a number of people

 

today we can hardly imagine a world

without broadcasting to imagine a time

when radio waves hadn't even been dreamt

of engineers continued to refine and

perfect our ability to transmit and

receive electromagnetic waves but their

initial discovery was ultimately a

triumph of pure science

from Maxwell through Hertz to launch but

still the very nature of electricity

itself remained unexplained what created

those electrical charges and currents in

the first place although scientists were

learning to exploit electricity they

still didn't know what it actually was

but this question was being answered

with experiments looking into how

electricity flowed through different

materials back in the 1850s one of

Germany's great experimentalists and a

talented glassblower Heinrich Geissler

created these beautiful show pieces

 

Geisler pumped most of the air out of

his intricate glass tubes and then had

small amounts of other gases pumped in

he then passed an electrical current

through them they glowed with stunning

colors and the current flowing through

the gas seen tangible although they were

designed purely for entertainment over

the next 50 years scientists or guys

'less tubes has a chance to study how

electricity flowed efforts were made to

pump more and more air out of the tubes

could the electric current pass through

nothingness through the vacuum this is a

very rare flick book film of the British

scientist who created a vacuum good

enough to answer that question his name

was William Crookes crooks created tubes

like this he pumped out as much of the

air as he could so that it was as close

to a vacuum as he could make it then

when he passed an electric current

through the tube he noticed a bright

glow on the far end a beam seemed to be

shining through the tube and hitting the

glass at the other end it seemed at last

we could see electricity the beam became

known as a cathode ray and this tube was

the forerunner of the cathode ray tube

that was used in television sets for

decades

physicist JJ Thompson discovered that

these beams were made up of tiny

negatively charged particles and because

they were carriers of electricity they

became known as electrons because the

electrons only moved in one direction

from the heated metal plate through the

positively charged plate at the other

end they behaved in exactly the same way

as BOCES semiconductor crystals but

whereas BOCES crystals were naturally

temperamental you had to find the right

spot for them to work these tubes could

be manufactured consistently they became

known as valves and they soon replaced

crystals in radio sets everywhere

 

these discoveries would lead to an

explosion of new technology early 20th

century electronics is all about what

you can do with valves so the radio

industry is built and valves early

television is built and valves early

computers are built with valves these

are the things that you build the

electronic world with having discovered

how to manipulate electrons flowing

through a vacuum scientists were now

keen to understand how they could flow

through other materials but that meant

understanding the things that made up

materials atoms

 

it was in the early years of the 20th

century that we finally got a handle on

exactly what atoms were made up of and

how they behaved and so what electricity

actually was on the atomic scale at the

University of Manchester Ernest

Rutherford's team were studying the

inner structure of the atom and

producing a picture to describe what an

atom looked like this revelation would

finally help explain some of the more

puzzling features of electricity by 1913

the picture of the atom was one in which

you had a positively charged nucleus in

the middle surrounded by negatively

charged orbiting electrons in patterns

called shells each of these shells

corresponding to an electron with a

particular energy now given an energy

boost an electron could jump from an

inner shell to an outer one and the

energy had to be just right if it wasn't

enough the electron wouldn't make the

transition and this boost was often

temporary because the electron would

then drop back down again to its

original shell as it did this it had to

give off its excess energy by spitting

out a photon and the energy of each

photon depended on its wavelength or as

we would perceive it it's color

understanding the structure of atoms

could now also explain nature's great

electrical light shows just like guys

'less tubes the type of gas the

electricity passes through defines its

color lightning has a blue tinge because

of the nitrogen in our atmosphere higher

in the atmosphere the gases are

different and so is the color of the

photons they produce creating the

spectacular Aurora's understanding atoms

how they fit together in materials and

how their electrons behave was the final

key to understanding the fundamental

nature of electricity

this is a Wimshurst machine and it's

used to generate electric charge

electrons are rubbed off these discs and

start a flow of electricity through the

metal arms of the machine

now metals conducts electricity because

the electrons are very weakly bound

inside their atoms and so can slosh

about and be used to flow as electricity

insulators on the other hand don't

conduct electricity because the

electrons are very tightly bound inside

the atoms and are not free to move about

the flow of electrons and hence

electricity through materials was now

understood conductors and insulators

could be explained what was more

difficult to understand was the strange

properties of semiconductors our modern

electronic world is built upon

semiconductors and would grind to a halt

without them Jagadish Chandra Bose may

have stumbled upon their properties back

in the 1890s but no one could have

foreseen just how important they were to

become but with the outbreak of the

Second World War things were about to

change

 

here in Oxford this newly-built physics

laboratory was immediately handed over

to the war research effort the

researchers here were tasked with

improving the British radar system Rader

was a technology that used

electromagnetic waves to detect enemy

bombers and as its accuracy improved it

became clear that valves just weren't up

to the job so the team had to turn to

old technology incentive valves they

used semiconductor crystals now they

didn't use the same sort of crystals

that Bost had developed instead they use

silicon this device is the silicon

crystal receiver as a tiny tungsten wire

coiled down and touching the surface of

a little silicon crystal it's incredible

how important a device it was it was the

first time silicon had really been

exploited as a semiconductor but for it

to work it needed to be very pure and

both sides in the war put a lot of

resources into purifying it in fact the

British had better silicon devices so

they must have had some cause of silicon

already at a time which we were just

started with you know and being in

Berlin

the British had better silicon

semiconductors because they had help

from laboratories in the u.s. in

particular the famous Bell Labs and it

wasn't long before physicists realized

that if semiconductors could replace

valves in radar perhaps they could

replace valves in other devices too like

amplifiers the simple vacuum tube with

its one-way stream of electrons had been

modified to produce a new device by

placing a metal grille in the path of

the electrons and applying a tiny

voltage to it a dramatic change in the

strength of the beam could be produced

these valves worked as amplifiers

turning a very weak electrical signal

into a much stronger one an amplifier is

something and once it's really simple

you just take a small current you turn

it into a large account but in other

ways it changes the world because when

you can amplify a signal you can send it

anywhere in the world as soon as the war

was over German experts Herbert matarae

and his colleague Heinrich Volker

started to build a semiconductor device

that could be used as an electrical

amplifier

and here is that first working model

that matter a embel car made if you look

inside you can see the tiny crystal and

the wires that make contact with it if

you pass a small current through one of

the wires this allows a much larger

current to flow through the other one so

it was acting as a signal amplifier

these tiny devices could replace big

expensive valves in long-distance

telephone networks radios and other

equipments where a faint signal needed

boosting matarae immediately realized

what he'd created but his bosses were

initially not interested not that is

until a paper appeared in a journal

announcing at Bell Labs discovery

a research team there had stumbled

across the same effect and now they were

announcing their invention to the world

they called it the transistor

they had December 1947 and we had at the

beginning 48 but just just just life you

know they had a little bit earlier the

effect but funnily enough the

transistors were just no good although

the European device was more reliable

than bell labs more experimental model

neither quite fulfilled their promise

they worked that were just too delicate

so the search was on for a more robust

way to amplify electrical signals and

the breakthrough came by accident in

Bell Labs silicon crystal expert Russell

all noticed that one of his silicon

ingots had a really bizarre property it

seemed to be able to generate its own

voltage and when you try to measure this

by hooking it up to an oscilloscope he

noticed that the voltage changed all the

time the amount of voltage generated

seemed to depend on how much light there

was in the room so by casting a shadow

over the crystal he saw the voltage

dropped more light meant the voltage

went up what's more when he turned a fan

on between the lamp and the crystal the

voltage started to oscillate with the

same frequency that the blades of the

fan were casting shadows over the

crystal

 

one of olds colleagues immediately

realized that the ingot had a crack in

it that formed a natural Junction and

this tiny natural Junction in an

otherwise solid block was acting just

like the much more delicate junction

between the end of a wire and a crystal

that boasts had discovered except here

it was sensitive to light the ingots had

cracked because either side contains

slightly different amounts of impurities

one side has slightly more of the

element phosphorus while the other has

slightly more of a different impurity

boron and electrons seem to be able to

move across from the phosphorus side to

the boron side but not vice-versa

photons of light shining down onto the

crystal were knocking electrons out of

the atoms but it was the impurity atoms

were driving this flow

phosphorus has an electron that is going

spare and boron is keen to accept

another so electrons tended to flow from

the phosphorus side to the boron side

and crucially only flowed one way across

the junction

 

the head of the semiconductor team

William Shockley saw the potential of

this one-way junction with inner crystal

but how would it be possible to create a

crystal with two junctions in it that

could be used as an amplifier another

researcher at Bell Labs called Gordon

teal had been working on a technique

that would allow just that

 

he discovered a special way to grow

single crystals of the semiconductor

germanium in this research institute

they grow semiconductor crystals in the

same way that teal did back in Bell Labs

only here they grow them much much

bigger at the bottom of this VAT is a

container with glowing hot molten

germanium just as pure as you can get it

inside it are a few atoms of whatever

impurity is required to alter is

conductive properties now the rotating

arm above has a seed crystal at the

bottom that has been dipped into the

liquid and will be slowly raised up

again

as the germanium cools and hardens it

forms a long crystal like an icicle

below the seed the whole length is one

single beautiful germanium crystal

 

Teil worked out that as the crystal is

growing other impurities can be added to

the vats and mixed in this gives us a

single crystal with thin layers of

different impurities creating junctions

within the crystal

  

 

this crystal with two junctions in it

was Shockley's dream applying a small

current through the very thin middle

section allows a much larger current to

flow through the whole triple sandwich

from a single crystal like this hundreds

of tiny solid blocks could be cut each

containing the two junctions that would

allow the movement of electrons through

them to be precisely controlled

these tiny and reliable devices could be

used in all sorts of electrical

equipment you cannot have the electronic

equipment that we have without tiny

components and you get a weird effect

that it is smaller they get the more

reliable they get it's a win-win

situation the Bell Labs team were

awarded the Nobel Prize for their

world-changing invention while a

European team were forgotten William

Shockley left Bell Labs and in 1955 set

up his own semiconductor laboratory in

rural California recruiting the

country's best physics graduates but the

celebratory mood didn't last long

because Shockley was almost impossible

to work for people left his company

because they just disliked the way he

treated them so the fact that Shockley

was that sees such a gate is why you

have Silicon Valley it starts that whole

process of spin-off and growth and new

companies and it all starts off with

Shockley being such a shocking human

being

 

the new companies were in competition

with each other to come up with the

latest semiconductor devices they may

transistors so small that huge numbers

of them could be incorporated into an

electrical circuit printed on a single

slice of semiconductor crystal these

tiny and reliable chips could be used in

all sorts of electrical equipment most

famously in computers a new age had

dawned today microchips are everywhere

they've transformed almost every aspect

of modern life

from communication to transport and

entertainment but perhaps just as

importantly our computers have become so

powerful they're helping us to

understand the universe in all its

complexity

a single microchip like this one today

can contain around 4 billion transistors

it's incredible how far technology has

come in 60 years it's easy to think that

with the great leaps we've made in

understanding and exploiting electricity

there's little left to learn about it

but we'd be wrong for instance making

the circuits smaller and smaller meant

that a particular feature of electricity

that had been known about for over a

century was becoming more and more

problematic resistance

a computer chip has to be continuously

cooled if you take away the fan this is

what happens while that's shooting up

100 120 130 degrees

 

200 degrees and it cut out that just

took a few seconds and the chip is well

and truly cooked you see as the

electrons flow through the chip they're

not just traveling around unimpeded

they're bumping into the atoms of

silicon and the energy being lost by

these electrons is producing Heat now

sometimes this was useful inventors made

electric heaters and ovens and whenever

they got something to glow white-hot

well that's a light bulb but resistance

in electronic apparatus and in power

lines is the major waste of energy and a

huge problem it's thought that

resistance wastes up to 20 percent of

all the electricity we generate it's one

of the greatest problems of modern times

and the search is on for a way to solve

the problem of resistance what we think

of as temperature is really a measure of

how much the atoms of the material are

vibrating and if the atoms are vibrating

then electrons flowing through are more

likely to bump into them so in general

the hotter the material the higher its

electrical resistance and the cooler it

is the lower the resistance but what

happens if you call something right down

close to absolute zero minus 273 degrees

Celsius well an absolute zero there's no

heat at all and so the atoms aren't

moving at all what happens then to the

flow of electricity the flow of

electrons

Using a special device called a cryostat

that can keep things close to absolute

zero we can find out inside this

cryostat in this coil is mercury the

famous liquid metal and it forms part of

an electric circuit

now this equipment here measures the

resistance in the mercury but look what

happens as I lower the mercury into the

coldest part of the cryostat there it is

the resistance has dropped to absolutely

nothing mercury like many substances we

now know have this property is called

becoming superconducting which means

there have no resistance at all to the

flow of electricity but these materials

only work when they're very very cold

if we could use a superconducting

material in our power cables and in our

electronic apparatus we'd avoid using so

much of our precious electrical energy

through resistance the problem of course

is that superconductors had to be kept

at extremely low temperatures then in

1986 a breakthrough was made in a small

laboratory near Zurich Switzerland IBM

physicists recently discovered their

superconductivity and the class of

materials that is being called one of

the most important scientific

breakthroughs in many decades this is a

block of the same material made by the

researchers in Switzerland it doesn't

look very remarkable but if you cool it

down with liquid nitrogen something

special happens it becomes a

superconductor and because electricity

and magnetism are so tightly linked that

gives it equally extraordinary magnetic

properties this magnet is suspended

levitating above the superconductor the

exciting thing is that although cold

this material is way above absolute zero

 

These magnetic fields are so strong that

not only can they support the weight of

this magnet but they should also support

my weight I'm about to be levitated

it's very very strange sensation

when this material was first discovered

in 1986 it created a revolution not only

had no one considered that it might be

superconducting but it was doing so at a

temperature much warmer than anyone has

thought possible

we are tantalisingly close to getting

room-temperature superconductors we're

not there yet but one day a new material

will be found and when we put that into

our electronic equipment we could build

a cheaper better more sustainable world

today materials have been produced that

exhibit this phenomenon at the sort of

temperatures you get in your freezer but

these new superconductors can't be fully

explained by the theoreticians so

without a complete understanding

experimentalists are often guided as

much by luck as they are by a proper

scientific understanding recently a

laboratory in Japan held a party in

which they ended up dosing their

superconductors with a range of

alcoholic beverages unexpectedly they

found that red wine improves the

performance of the superconductors

 

Electrical research now has the

potential once again to revolutionize

our world if room-temperature

superconductors can be found

 

Our addiction electricity's power is

only increasing and when we fully

understand how to exploit

superconductors a new electrical world

will be upon us it's going to lead to

one of the most exciting periods of

human discovery and invention a brand

new set of tools techniques and

technologies to once again transform the

world

 

Electricity has changed our world only a

few hundred years ago it was seen as a

mysterious and magical wonder

then elect out of the laboratory with a

series of strange and wondrous

experiments eventually being captured

and put to use it revolutionized

communication first through cables and

then as waves through electricity's

far-reaching fields it powers and lights

the modern world today we can hardly

imagine life without electricity it

defines our era and will be utterly lost

without it

and yet it still offers us more we stand

once again at the beginning of a new age

of discovery a new revolution

but above all else there's one thing

that all those who deal in the science

of electricity know it's story is not

over yet.

 

 




Who Discovered the Electricity? Reviewed by Author on September 01, 2020 Rating: 5

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