All language subtitles for BBC.Shock.And.Awe.The.Story.Of.Electricity.2011.S01E02.The.Age.of.Invetion.AC3.2.0.x264.1080p.eng

Electricity is one of
nature's greatest forces.

And by the middle of the 20th
century, 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,
Nicola 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 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, binding 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 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,

that an electric current
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.

Oersted's discovery
sparks off a whole new spate

of inventive activity around and about

the fields of electricity.

You could 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

re-creating 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,
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 on to 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 disc

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 disc,

leaving a positive charge at the center.

And once the disc 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 created electrical power
directly from mechanical power.

Although 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,

for Faraday, what it did was open up

a decade of powerful
research, became 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 from 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 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 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
the 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 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.

As 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 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 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 crisscrossed

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 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
Bright's original notebook.

You could 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.

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, the 27th of 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

into a world in which information took

seconds or minutes to travel.

It is far more profound,
I think, than 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 currents

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 may 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.

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 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 who

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.

One of them talked about
how he 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,

if they succeeded with Edison,

that 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 at 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.

Now 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 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 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,
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 this
team were about to launch

their most expensive
and risky project yet,

America's first power station,

generating continuous direct current.

Just before three PM on the
Fourth of September, 1882,

Thomas Edison, surrounded
by a gaggle of bankers,

dignitaries and reporters,
entered J.P. Morgan's

building right behind me,
flipped 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
crisscrossed with hundreds

of cables used for telegraphs,

telephones and arc street lightning.

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, right.

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.

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 centers

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 fallouts
in scientific history.

His name was Nicola
Tesla, and he was right

under Edison's nose.

Nicola 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 that they
handled their self, appearance,

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 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, he
cares about his manner,

indeed, he even cares
about 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 the fact that he has

a bit of a pointy chin.

The life and death
of Nicola 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 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 electric current that
alternate 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,

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 and 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 a distance
into you 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 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 Nicola 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 visualize it in three dimensions,

and they often say that the
people who 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 of 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, 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 motor's central

moving part to it, and then faded.

The second overlapping
current fed the next coil,

dragging the moving parts
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 its 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 at a waterfall like
Niagara, and you could then

distribute the power over long distances

and serve all the people in a major city

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.

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 Nicola Tesla story.

Where it's difficult to
separate fact from fiction.

Tesla was paid $75,000 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 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,
right, 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 light, right.

It's the system that's safe.

You adopt the Edison system,

you can be sure it's going to be safe.

Edison claimed that AC
was a more dangerous type

of current than DC, and he
highlighted every accident

for Westhinghouse'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 byWestinghouse 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 the Sixth

of 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 Nicola Tesla was
about to do something

that had never been seen before,

something so wondrous and
daring that it would live on

forever 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 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.

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 currents.

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.

Nicola 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 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 evenly 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 3327

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 Nicola 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,

Nicola 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.