All language subtitles for BBC.Shock.and.Awe.The.Story.of.Electricity.2of3.The.Age.of.Invention.HDTV.x264.AAC.MVGroup

Electricity is one of nature's
greatest forces.

we'd harnessed it to light
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 out

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 laid back on his bed to die.

It would 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 29th of February, 1812,

a 20-year-old self-educated
bookbinder 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, binding books.

But in the evenings, he'd 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 they 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 chemist
of the time, Sir Humphry Davy.

It was to change
young Faraday's life forever.

After watching Davy,
awe 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,
Davy had appointed him

as an assistant
at the Royal institution.

With Davy as his patron and,
well, his boss,

Faraday studied
all manner of chemistry.

But what would inspire
his greatest breakthroughs...

were 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 an electric current
through a copper rod

and brought it close
to a magnetic compass needle

and saw that it made
the needle rotate.

To Oersted, it was remarkable.

He'd shown, for the first time,

an electric current
can create a magnetic force.

He'd bound electricity
and magnetism together.

Today we call it electro-magnetism.

And it's one of the fundamental
forces of nature.

Oersted's discovery
sparks off a whole new

aspect 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 Oersted'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.

But Faraday was about to take
this experiment further.

One of the lasting effects

of Faraday's discovery of
electromagnetic rotations in 1821,

was that it showed that there was
a relationship of some sort

between electricity and 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 centre,

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 disk was spun.

He'd created electrical power
directly from mechanical power.

Although Faraday's discovery
of conduction 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,

for Faraday what it did is open up
a decade of powerful research,

because it gave him a clue about
how he should pursue his research.

While Faraday continued his work,

trying to understand the very nature
of electricity,

inventors across Europe
were less interested in the science

and more interested in how
electricity could make them money.

What's actually quite remarkable,
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 it's a force, or a
fluid, or a principal, 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
had been made.

This would 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 magnet, an electromagnet.

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 magnet,

so Henry and Sturgeon discovered

that by adding more coils
in their current 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 experiment

of sprinkling iron filings
on top of the magnet.

If I give it a tap,

see the iron filings
follow the contours of the field.

This allows us to visualise
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 that was many,
many times more powerful.

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,

look at 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 tonne-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 current for a dash,
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

and the 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'll 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
businessmen and British engineers

joined forces
to prove this could be done.

Attempt after attempt
ended in disaster.

The heavy cables kept snapping
in heavy seas and storms.

Finally, on 29th July 1858,

two parts of a cable were spliced
together in mid-Atlantic.

You see, a single cable was simply
too big to be carried by one ship.

Then one end was taken
to Newfoundland,

and the other end
to south-west 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 Bright's
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
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.

Well, the 1858 cable
was never fully repaired,

and the end finally came when
British engineer Wildman 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 dash.

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 had 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 27th July 1866,

a message was sent
from Ireland to Newfoundland.

Clear and crisp.

"A 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.

The change from a world where it
took days or weeks or months

for information to travel,

to a world in which information
took seconds or minutes to travel -

it is far more profound

than almost anything that's
taken place during my lifetime.

The invention of the telegraph
changed ordinary people's lives.

But it would be the breakthroughs

in how we used continuously
flowing electric current

that 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'd 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 Humphry 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 light

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.

For 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.
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 fore.

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, with people
that are willing to put their cash

where Edison's mouth is,
so to speak,

and back him
in this 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 hardly ever saw his children

cos he was in the lab all the time.

But they knew they were in the midst
of something really important.

That if Edison succeeded,

if they succeeded with Edison,
their futures were secure.

Edison's dream was to bring electric
light 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

had 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

worked 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.

Inside this jar, I have a filament
made out of ordinary pencil lead,

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,
its 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 parchment to cork.

Edison even tested his
engineers' beard hair.

Eventually,
he settled on bamboo fibre,

while Swan used
a treated cotton thread.

Edison and Swan's 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, whilst 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'd developed a ground-breaking
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 centre 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 3pm on the
4th September 1882, 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've 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 current
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 telegraphs,

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 for underground 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,
or 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.

Edison chose this area for a reason.

Wall Street.

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.

Had 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 centres of our towns and cities.

And it would be extraordinarily
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 fall-outs

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 they handled their self,
appearance, and their manners,

and the way that they constructed
a public image for themselves.

Edison couldn't care less
about the clothes he had on

and if he spilt chemicals
on his good Sunday suit,

then he spilt chemicals
on his good Sunday suit.

He was, you know, basically,
a very kind of slovenly guy.

Tesla, on the other hand,

even as a young man in his mid 20s,
is thinking about his appearance,

how he comes across to people.

So he cares about his clothes,
his manner.

Indeed, he even cares about
how his photograph,

his portraits are taken,

and he always wants to make sure
he has a nice, three-quarter profile

so you don't see 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,
cut-throat 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 knew
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 that.

It's an 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 realised that as you
raise the voltage of any current

that you transmit
from point A to point B,

it's 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
would 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 transformer.

Alternating current
allows you to use a transformer

to make that switch
from the high transmission voltage

to the lower voltage
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 entrepreneur

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 plan it.

And he had what modern-day
psychologists would call

an eidetic memory. He could basically

remember everything that he saw

and then visualise it
in three dimensions.

And they often say
people that 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
that 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 movement

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.

He was not just
tinkering with one 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,

thinking outside the box,

doing things very differently
to his fellow 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

energised a coil of wire
inside the motor,

creating an electromagnetic field

which attracted the motor's
central moving part to it

and then faded.

The second overlapping current
fed the next coil,

dragging the moving 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 distribute the power
over long distances,

and serve all the people

in a major city
or metropolitan centre.

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.

But 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,

where it's difficult
to separate fact from fiction.

Tesla was paid 75,000
for his alternating current patents

and offered 2.50

for every horse power
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 AC 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 over 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.

Edison.

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 would become known as
the War of the Currents.

Both camps tried to undercut
each other on cost,

but Edison believed
his beloved direct current

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 Edison was trying to do

was to again define his DC system
as the safe system.

It's better than
electric street arc lights,

it's better than gas,

and it's now better than high
voltage AC incandescent lighting.

Right? It's the system that's safe.

You adopt the Edison system,
you can be sure it's safe.

Edison claimed that AC

was a more dangerous type
of current than DC

and he highlighted every accident
to Westinghouse's 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 fully 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 he 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 Westinghoused.

And at precisely 6:32,

on the morning of 6th August 1890,

a 45-year-old man, William Kemmler,

was strapped to a wooden chair

and two 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 had never been seen before.

Something so wondrous and daring

that it would live on for ever
in the memories of those who saw it.

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 mail or mask,

tens of thousands of volts,
produced by a Tesla coil,

passed across his body and through
the end of a lamp 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.

His demonstrations showed
that if handled correctly,

alternating current 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 current.

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's 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 he was also hugely complicated,

and sadly, later in life,
he became more and more troubled.

He was fixated
with the number three,

counting it out loud
while he walked,

and he developed strange phobias
with germs

and with women wearing
pearl jewellery.

In many ways, his brilliant mind
simply spun out of control.

As Tesla's life unravelled,

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 centre of Manhattan.

He even fell in love with one
particularly unusual white bird

and when it died,

he was left heart broken.

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 3327 of the New York 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 generate 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.

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.

Subtitles by Red Bee Media Ltd 2011

E-mail subtitling@bbc.co.uk