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
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