All language subtitles for BBC Shock and Awe - The Story of Electricity - 01x03 - Revelations and Revolutions.PDTV.XviD

On the 14th 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 2,000 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 revolutionise
the Victorian world

of brass and telegraph wire.

This lecture would mark the birth
of the modern electrical world,

a world dominated by silicone
and mass wireless communication.

In this programme,
we discover how electricity
connected the world together

through broadcasting
and computer networks,

and how we finally learnt 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 in to any power source,

but they still light up.

It's 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 florescent tubes are lit
purely because they are 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
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 current,
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 absorbed 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's original apparatus

and its beauty is in
its sheer simplicity.

Heat generates and 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.

Lodge 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 a bit of tweaking,

he saw these glowing patches
formed a pattern.

The blue glow and electrical sparks
occurred in distinct patches

evenly spaced along the wires.

He realised 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, Lodge prepared

to announce it to the world, at that
summer's annual 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 minute spark.

And as he carried his receiver
to 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
Heinrik Hertz had just
published astounding results.

He had detected Maxwell's waves
travelling through space.

"We have snatched
the thunderbolt from Jove himself

"and enslaved the all prevailing
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.

Hertz's spectacular demonstration
of electromagnetic waves,
what we now call radio waves,

though he didn't know it at the time,
will 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 starts in Oxford,
in the summer of 1894.

Hertz had died suddenly
earlier that year,

and so Lodge 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.

Lodge's improvement on this
was to set up this tube
full of iron fillings.

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...

BELL TINKLES
..it sets off the bell
at the receiver.

And it's doing that with
no connections between the two.

It's like magic.

BELL RINGING/ELECTRICAL BUZZING

If 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.

It's quite incredible.

BELL RINGS

It might not have been
the most dramatic demonstration
the audience had ever seen,

but it certainly still created
a sensation among the crowd.

Lodge's apparatus,
laid out like this,

no longer looked like
a scientific experiment.

In fact, it looked remarkably
like those telegraph machines

that had revolutionised
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 published his 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 Lodge's
reports with excitement

and began experimenting
with Hertzian waves.

Two utterly different characters
were to be inspired by it.

Both would bring improvements
to the wireless telegraph,

and both would be remembered
for their contribution to science
far more than Oliver Lodge.

The first was Guglielmo 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.

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
Lodge's 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 had 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 set to work.

This is a report of the 66th meeting
of the British Association

in 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'd built and improved on
the detector that Lodge described,

because in the hot,
sticky Indian climate,

he'd found that the metal filings
inside the tube that Lodge
used 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 onboard ships,

so had great potential for
the vast British naval fleet.

Britain was the centre 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 sort of a new,
cutting-edge field, but Marconi

wasn't a trained scientist, so
he came at things in a different way,

which may have been why he progressed
so quickly in the first place.

And he was very good at forming
connections with the people

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 heaving with business

from the empire's postal
and telegraphy services.

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 Preece, immediately saw
the technology's potential.

So, Preece 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 practise sending and receiving
electromagnetic waves.

The engineers helped him
improve his apparatus,
and then Preece and Marconi together

demonstrated it to influential
people in Government and the Navy.

What Preece didn't realise

was that even as he was proudly
announcing Marconi's successful
partnership with the Post Office,

Marconi 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 on 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 Marconi is famous
is not because of that invention.

He doesn't invent radio,
but he improves it

and turns it into a system.

Lodge doesn't do that.
And that's why we 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 Preece,
was disappointed and hurt

when he found out 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 at 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 scientific integrity
and 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 replaces 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 centre of a radio industry.

Bose's 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 varied behaviour.

Take this crystal, for example.

If I can touch it
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 round
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 semi-conductor.

And it found its first use
in detecting electromagnetic waves.

When Bose used a crystal like this
in his circuits

instead of the tube of 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 on 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 to scientists and engineers,
this strange behaviour

had a profound and 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 patent
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'd 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 this 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.'

Hertz made a great advance.

He discovered how to produce
and detect waves in space,

thus bringing the ether
into practical use.

Harnessing it, harnessing it
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 discovery was ultimately
a triumph of pure science,

from Maxwell, through Hertz,
to Lodge.

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 glass blower,
Heinrich Geissler,

created these beautiful showpieces.

ELECTRICITY BUZZES

Geissler pumped most of the air
out of these 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 colours,

and the current flowing
through the gas seemed tangible.

Although they were designed
purely for entertainment,

over the next 50 years, scientists
saw Giessler's tubes as 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.

Crookes create 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 electrical
current through the tube...

ELECTRICAL BUZZING

..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 Bose's semi-conductor crystals.

But, whereas Bose's 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 industries
is built on valves,

early television is built on valves,

early computers are built
with valves.

These are what 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
corresponded 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,
its colour.

Understanding the structure of atoms
could now also explain

nature's great
electrical light shows.

THUNDER

Just like Geissler's tubes,

the type of gas the electricity
passes through defines its colour.

Lightning has a blue tinge because
of the nitrogen in our atmosphere.

Higher in the atmosphere,
the gases are different

and so is the colour
of the photons they produce,

creating the spectacular auroras.

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 conduct 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 semi-conductors.

Our modern electronic world
is built upon semi-conductors

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.

Radar 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 -

instead of valves, they used
semi-conductor crystals.

Now, they didn't use
the same sort of crystals

that Bose had developed -
instead they used silicon.

This device is
a silicon crystal receiver.

There's 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 semi-conductor,

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 coils
of silicon already at that time

which we were just starting
with, you know, in Berlin.

The British had better
silicon semi-conductors

because they had help
from laboratories in the US,

in particular, the famous Bell Labs.

And it wasn't long before
physicists realised

that if semi-conductors
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 grill
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,
in one sense, really simple.

You just take a small current,
you turn it into a larger current.

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 expert Herbert Matare

and his colleague, Heinrich Welker,
started to build

a semi-conductor device that could
be used as an electrical amplifier.

And here is that first working model
that Matare and Welker 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 equipment

where a faint signal
needed boosting.

Matare immediately realised
what he'd created,

but his bosses were
initially not interested.

Not, that is, until a paper
appeared in a journal

announcing a 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 it in December 1947,
and we had it in beginning '48.

But just, just life, you know.

They had it a little bit earlier,
the effect.

But, funnily enough, their
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,
but 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 Ohl

noticed that one of his silicon
ingots had a really
bizarre property.

It seemed to be able
to generate its own voltage

and when he tried to measure this
by hooking it up to an Oscilloscope,

he noticed that the voltage
changed all the time.

The amount of voltage it 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 Ohl's colleagues
immediately realised

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 Bose had discovered.

Except here, it was
sensitive to light.

The ingot had cracked because
either side contained

slightly different amounts
of impurities.

One side had slightly more
of the element phosphorous,

while the other had slightly more
of a different impurity - boron.

And electrons seemed
to be able to move across

from the phosphorous 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
that were driving this flow.

Phosphorous has an electron
that is going spare...

and boron is keen
to accept another,

so electrons tended to flow
from the phosphorous side

to the boron side and, crucially,
only flowed one way
across the junction.

The head of the semi-conductor team,
William Shockley,

saw the potential of this
one-way junction within a 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'd discovered a special way
to grow single crystals

of the semi-conductor germanium.

In this research institute,
they grow semi-conductor 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 its 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.

Teal worked out that,
as the crystal is growing,

other impurities can be added
to the vat 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 -
the smaller they get,
the more reliable they get,

it's a win-win situation.

APPLAUSE

The Bell Labs team
were awarded the Nobel Prize
for their world changing invention,

while the European team
were forgotten.

William Shockley left Bell Labs,

and in 1955 set up
his own semi-conductor 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 actually such a git

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
semi-conductor devices.

They made transistors so small

that huge numbers of them
could be incorporated
into an electrical circuit

printed on a single slice
of semi-conductor 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
four 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.

Wow! 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 travelling around
unimpeded.

They're bumping into
the atoms of silicone,

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%
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 in a 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 cool something right down,

close to absolute zero,

-273 degrees Celsius?

Well, at 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.

It's called
"becoming super conducting",

which means they 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 losing 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
superconductivity
in a new 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.

Oh, it's a 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 had 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 electronics 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 revolutionise our world,

IF room temperature superconductors
can be found.

Our addiction to 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, it leapt out of the laboratory
with a series of strange
and wondrous experiments,

eventually being captured
and put to use.

It revolutionised 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 we'd 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 -

its story is not over yet.

To find out more about
the story of electricity,

and to put your power knowledge
to the test,

try the Open University's
interactive energy game.

Go to:

..and follow links
to the Open University.

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