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Electricity is one of nature's greatest forces. | 0:00:06 | 0:00:10 | |
And by the middle of the 20th century, | 0:00:12 | 0:00:14 | |
we'd harnessed it to light and power our modern world. | 0:00:14 | 0:00:18 | |
Hundreds of years of scientific discoveries | 0:00:20 | 0:00:23 | |
and inventions brought us here. | 0:00:23 | 0:00:26 | |
But it would take the eccentric genius of one man | 0:00:27 | 0:00:31 | |
to unlock the full potential of electrical power. | 0:00:31 | 0:00:34 | |
In the winter of 1943, | 0:00:36 | 0:00:38 | |
Nikola Tesla looked out | 0:00:38 | 0:00:40 | |
across the Manhattan skyline | 0:00:40 | 0:00:43 | |
for the very last time. | 0:00:43 | 0:00:45 | |
Tesla had been born into a world powered by steam and lit by gas. | 0:00:45 | 0:00:50 | |
But before his eyes, he saw a new world. | 0:00:52 | 0:00:55 | |
A world transformed, | 0:00:55 | 0:00:57 | |
a world powered by electricity. | 0:00:57 | 0:01:00 | |
His world. | 0:01:00 | 0:01:01 | |
Frail, lonely | 0:01:07 | 0:01:10 | |
and still mourning the death of one of his beloved pigeons, | 0:01:10 | 0:01:13 | |
this extraordinary and eccentric genius | 0:01:13 | 0:01:17 | |
knew that his life's work was done and he laid back on his bed to die. | 0:01:17 | 0:01:22 | |
It would be three days before anyone found his body. | 0:01:23 | 0:01:26 | |
Just over 200 years ago, early scientists | 0:01:38 | 0:01:42 | |
discovered electricity could be much more than simply a static charge. | 0:01:42 | 0:01:47 | |
It could be made to flow in a continuous current. | 0:01:47 | 0:01:52 | |
But they were about to discover something profound. | 0:01:58 | 0:02:01 | |
That electricity is connected to magnetism. | 0:02:01 | 0:02:05 | |
Harnessing the link between magnetism and electricity | 0:02:06 | 0:02:10 | |
would completely transform the world | 0:02:10 | 0:02:13 | |
and allow us to generate seemingly limitless | 0:02:13 | 0:02:16 | |
amounts of electrical power. | 0:02:16 | 0:02:18 | |
This is the story of how scientists and engineers | 0:02:26 | 0:02:30 | |
unlocked the nature of electricity | 0:02:30 | 0:02:33 | |
and then used it in an extraordinary century of innovation and invention. | 0:02:33 | 0:02:39 | |
But not before one of the most shocking | 0:02:39 | 0:02:42 | |
engineering rivalries in history was finally laid to rest. | 0:02:42 | 0:02:47 | |
Our story begins in London, | 0:03:03 | 0:03:06 | |
at the beginning of the 19th century, | 0:03:06 | 0:03:08 | |
with a young man who would further our understanding of electricity | 0:03:08 | 0:03:12 | |
as much as any other. | 0:03:12 | 0:03:14 | |
On 29th of February, 1812, | 0:03:14 | 0:03:17 | |
a 20-year-old self-educated bookbinder called Michael Faraday | 0:03:17 | 0:03:23 | |
came here to the Royal institution of Great Britain. | 0:03:23 | 0:03:27 | |
He was surrounded by the great and the good of the academic world. | 0:03:34 | 0:03:38 | |
And he was about to listen | 0:03:38 | 0:03:40 | |
to one of the greatest scientific minds of the age. | 0:03:40 | 0:03:43 | |
Faraday, the son of a blacksmith, had finished his formal education | 0:03:47 | 0:03:52 | |
when he was just 12 years old. | 0:03:52 | 0:03:55 | |
He would never get to university. | 0:03:55 | 0:03:57 | |
But he wasn't finished with learning, | 0:03:57 | 0:03:59 | |
as he was fascinated by science. | 0:03:59 | 0:04:02 | |
Faraday worked long and hard during the day, binding books. | 0:04:04 | 0:04:09 | |
But in the evenings, he'd read whatever scientific literature | 0:04:09 | 0:04:13 | |
he could lay his hands on. | 0:04:13 | 0:04:15 | |
He loved learning new things about the world | 0:04:15 | 0:04:18 | |
and he had this constant desire, this passion, | 0:04:18 | 0:04:21 | |
to understand why things were they way they were. | 0:04:21 | 0:04:25 | |
Reading scientific papers was one thing. | 0:04:28 | 0:04:32 | |
But to really satisfy his craving for knowledge, | 0:04:32 | 0:04:36 | |
Faraday was desperate to see the experiments themselves. | 0:04:36 | 0:04:39 | |
And he eventually got his chance | 0:04:39 | 0:04:42 | |
when he was given a ticket to attend one of the last lectures | 0:04:42 | 0:04:46 | |
of England's greatest chemist of the time, Sir Humphry Davy. | 0:04:46 | 0:04:50 | |
It was to change young Faraday's life forever. | 0:04:53 | 0:04:57 | |
After watching Davy, awe inspired and full of ideas, | 0:05:00 | 0:05:04 | |
Faraday knew what he wanted to do with his life. | 0:05:04 | 0:05:07 | |
He was determined to dedicate himself to furthering science. | 0:05:07 | 0:05:12 | |
And that's just what he did. | 0:05:12 | 0:05:15 | |
Within a year, Davy had appointed him | 0:05:15 | 0:05:19 | |
as an assistant at the Royal institution. | 0:05:19 | 0:05:21 | |
With Davy as his patron and, well, his boss, | 0:05:23 | 0:05:27 | |
Faraday studied all manner of chemistry. | 0:05:27 | 0:05:31 | |
But what would inspire his greatest breakthroughs... | 0:05:31 | 0:05:36 | |
were the invisible forces of electricity and magnetism. | 0:05:36 | 0:05:40 | |
In 1820, both were being studied by a Danish scientist, | 0:05:43 | 0:05:48 | |
Hans Christian Oersted, | 0:05:48 | 0:05:50 | |
who'd made an extraordinary discovery. | 0:05:50 | 0:05:53 | |
He passed an electric current through a copper rod | 0:05:55 | 0:05:59 | |
and brought it close to a magnetic compass needle | 0:05:59 | 0:06:03 | |
and saw that it made the needle rotate. | 0:06:03 | 0:06:07 | |
To Oersted, it was remarkable. | 0:06:07 | 0:06:09 | |
He'd shown, for the first time, | 0:06:09 | 0:06:12 | |
an electric current can create a magnetic force. | 0:06:12 | 0:06:16 | |
He'd bound electricity and magnetism together. | 0:06:16 | 0:06:20 | |
Today we call it electro-magnetism. | 0:06:20 | 0:06:23 | |
And it's one of the fundamental forces of nature. | 0:06:23 | 0:06:27 | |
Oersted's discovery sparks off a whole new | 0:06:29 | 0:06:31 | |
aspect of inventive activity | 0:06:31 | 0:06:34 | |
around and about the fields of electricity. | 0:06:34 | 0:06:40 | |
You can almost see electrical experimenters vying, | 0:06:40 | 0:06:43 | |
competing with each other, | 0:06:43 | 0:06:44 | |
to find new links between electricity and the other powers of nature. | 0:06:44 | 0:06:48 | |
At the Royal institution, | 0:06:48 | 0:06:51 | |
Faraday set about recreating Oersted's work, | 0:06:51 | 0:06:55 | |
which would mark his first steps to fame and fortune. | 0:06:55 | 0:06:59 | |
And through his rigorous research, | 0:06:59 | 0:07:02 | |
he concluded that there must be a flow of forces | 0:07:02 | 0:07:06 | |
acting between the wire and the compass needle. | 0:07:06 | 0:07:09 | |
The device he designed to demonstrate it | 0:07:09 | 0:07:12 | |
would change the course of history. | 0:07:12 | 0:07:15 | |
Faraday created a circuit using a battery like this, | 0:07:15 | 0:07:21 | |
a pair of wires and a mercury bath. | 0:07:21 | 0:07:25 | |
Now, the circuit carries on through these copper posts, | 0:07:25 | 0:07:28 | |
and this wire hangs freely, it dangles into the mercury. | 0:07:28 | 0:07:32 | |
Now, because mercury is such a good conductor, | 0:07:32 | 0:07:35 | |
it completes the circuit. | 0:07:35 | 0:07:38 | |
When the current runs through the circuit... | 0:07:38 | 0:07:42 | |
..it generates a circular magnetic force-field around the wire. | 0:07:43 | 0:07:48 | |
Now, this interacts with the magnetism from a permanent magnet | 0:07:48 | 0:07:52 | |
that Faraday had placed in the middle of the mercury. | 0:07:52 | 0:07:55 | |
Together they forced the wire to move. | 0:07:55 | 0:07:59 | |
Faraday had proved that this invisible force really does exist | 0:07:59 | 0:08:03 | |
and he could see its effect - circular motion. | 0:08:03 | 0:08:08 | |
This beautiful device was the first to convert electric current | 0:08:08 | 0:08:14 | |
into continuous motion. | 0:08:14 | 0:08:16 | |
Basically, it's the earliest ever electric motor. | 0:08:16 | 0:08:20 | |
But Faraday was about to take this experiment further. | 0:08:25 | 0:08:29 | |
One of the lasting effects | 0:08:33 | 0:08:34 | |
of Faraday's discovery of electromagnetic rotations in 1821, | 0:08:34 | 0:08:38 | |
was that it showed that there was a relationship of some sort | 0:08:38 | 0:08:41 | |
between electricity and magnetism and motion. | 0:08:41 | 0:08:44 | |
Faraday explored this relationship in detail | 0:08:47 | 0:08:51 | |
and set himself an even more difficult challenge. | 0:08:51 | 0:08:54 | |
To use magnetism and motion to make electricity. | 0:08:55 | 0:09:00 | |
Eventually, his obsession, | 0:09:03 | 0:09:05 | |
hard work and determination paid off. | 0:09:05 | 0:09:07 | |
The breakthrough came | 0:09:11 | 0:09:13 | |
on the 17th of October 1831, | 0:09:13 | 0:09:16 | |
when Faraday took a magnet like this and moved it | 0:09:16 | 0:09:20 | |
in and out of a coil of wire. | 0:09:20 | 0:09:24 | |
He was able to detect a tiny electric current in the coil, | 0:09:24 | 0:09:29 | |
moving one way... | 0:09:29 | 0:09:33 | |
..and then the other. | 0:09:33 | 0:09:36 | |
Faraday knew he was onto something. | 0:09:37 | 0:09:41 | |
A few days later, | 0:09:41 | 0:09:42 | |
instead of moving the magnet through the conducting wire coil, | 0:09:42 | 0:09:46 | |
he set up the equivalent experiment | 0:09:46 | 0:09:48 | |
by moving a conducting copper plate through the magnetic field. | 0:09:48 | 0:09:53 | |
He didn't know it at the time, | 0:09:57 | 0:09:59 | |
but as his spinning disk cut through this magnetic field, | 0:09:59 | 0:10:03 | |
billions of negatively charged electrons | 0:10:03 | 0:10:06 | |
were deflected from their original circular course, | 0:10:06 | 0:10:09 | |
and began to drift towards the edge. | 0:10:09 | 0:10:12 | |
A negative charge built up at the outer edge of the disk, | 0:10:14 | 0:10:18 | |
leaving a positive charge at the centre, | 0:10:18 | 0:10:20 | |
and once the disk was connected to wires, | 0:10:20 | 0:10:23 | |
the electrons flowed in a steady stream. | 0:10:23 | 0:10:27 | |
Faraday had generated a continuous flow of electric current. | 0:10:27 | 0:10:32 | |
Unlike a battery, | 0:10:34 | 0:10:35 | |
his current flowed for as long as his copper disk was spun. | 0:10:35 | 0:10:40 | |
He'd created electrical power directly from mechanical power. | 0:10:40 | 0:10:45 | |
Although Faraday's discovery of conduction was extraordinarily important in its own right, | 0:10:45 | 0:10:50 | |
and had profound effects for the understanding of electricity | 0:10:50 | 0:10:54 | |
and technology for the rest of the 19th century, | 0:10:54 | 0:10:57 | |
for Faraday what it did is open up a decade of powerful research, | 0:10:57 | 0:11:03 | |
because it gave him a clue about how he should pursue his research. | 0:11:03 | 0:11:07 | |
While Faraday continued his work, | 0:11:08 | 0:11:12 | |
trying to understand the very nature of electricity, | 0:11:12 | 0:11:15 | |
inventors across Europe were less interested in the science | 0:11:15 | 0:11:18 | |
and more interested in how electricity could make them money. | 0:11:18 | 0:11:24 | |
What's actually quite remarkable, certainly from a contemporary perspective, | 0:11:24 | 0:11:28 | |
is that, by and large, | 0:11:28 | 0:11:30 | |
nobody really seems to care very much what electricity is. | 0:11:30 | 0:11:35 | |
You don't have great theoretical debates | 0:11:35 | 0:11:37 | |
as to whether it's a force, or a fluid, or a principal, or a power. | 0:11:37 | 0:11:41 | |
What they're really interested in is what electricity can do. | 0:11:41 | 0:11:45 | |
Faraday, living in a world of steam power, | 0:11:47 | 0:11:51 | |
was informing the scientific community | 0:11:51 | 0:11:54 | |
about the nature of electricity, | 0:11:54 | 0:11:56 | |
but at the same time another breakthrough | 0:11:56 | 0:11:59 | |
in how we could actually use it had been made. | 0:11:59 | 0:12:03 | |
This would be the first device | 0:12:03 | 0:12:05 | |
that really brought electricity out of the laboratory | 0:12:05 | 0:12:08 | |
and into the hands of ordinary people. | 0:12:08 | 0:12:12 | |
The telegraph. | 0:12:12 | 0:12:14 | |
The key to understanding the telegraph | 0:12:17 | 0:12:20 | |
is understanding a special kind of magnet, an electromagnet. | 0:12:20 | 0:12:26 | |
Basically, a magnet created by an electric current. | 0:12:26 | 0:12:29 | |
The first electromagnets were developed independently | 0:12:32 | 0:12:36 | |
by William Sturgeon in Britain and Joseph Henry in America. | 0:12:36 | 0:12:40 | |
And just as Faraday had discovered that by coiling his wire, | 0:12:40 | 0:12:45 | |
he could increase the current in it produced by the moving magnet, | 0:12:45 | 0:12:49 | |
so Henry and Sturgeon discovered | 0:12:49 | 0:12:51 | |
that by adding more coils in their current carrying wires, | 0:12:51 | 0:12:55 | |
they could make a more concentrated magnetic field. | 0:12:55 | 0:12:59 | |
Basically, the more coils, the more turns, the stronger the magnet. | 0:12:59 | 0:13:04 | |
So if I pass a current through this electromagnet, | 0:13:04 | 0:13:08 | |
you can actually see the effects of the magnetic field. | 0:13:08 | 0:13:12 | |
This is the standard school experiment | 0:13:12 | 0:13:15 | |
of sprinkling iron filings on top of the magnet. | 0:13:15 | 0:13:18 | |
If I give it a tap, | 0:13:18 | 0:13:20 | |
see the iron filings follow the contours of the field. | 0:13:20 | 0:13:25 | |
This allows us to visualise the effects of magnetism. | 0:13:25 | 0:13:28 | |
To make an electromagnet even stronger, | 0:13:30 | 0:13:33 | |
Henry and Sturgeon discovered that they could place | 0:13:33 | 0:13:37 | |
certain kinds of metal inside the electromagnetic coil. | 0:13:37 | 0:13:42 | |
The reason iron is so effective is fascinating | 0:13:42 | 0:13:44 | |
because you can think of it as being made up of lots of tiny magnets, | 0:13:44 | 0:13:48 | |
all pointing in random directions. | 0:13:48 | 0:13:51 | |
At the moment, this is not a magnet. | 0:13:51 | 0:13:53 | |
The tiny magnets inside are aligned similarly to these compass needles. | 0:13:53 | 0:13:58 | |
If you see, they're all pointing in different directions. | 0:13:58 | 0:14:01 | |
But when you apply a magnetic field, they all align together, | 0:14:01 | 0:14:08 | |
they all combine, these magnets, | 0:14:08 | 0:14:09 | |
and cumulatively they add to the strength of the electromagnet. | 0:14:09 | 0:14:14 | |
So what Henry and Sturgeon did, | 0:14:14 | 0:14:17 | |
was place two electromagnetic coils on each arm of their horseshoe, | 0:14:17 | 0:14:23 | |
to create something that was many, many times more powerful. | 0:14:23 | 0:14:27 | |
And we can see the power of this horseshoe electromagnet. | 0:14:31 | 0:14:36 | |
If I turn it on and use something slightly bigger than iron filings, | 0:14:36 | 0:14:41 | |
these small pieces of iron, | 0:14:41 | 0:14:44 | |
look at the strength of the magnetic field, holding them in place. | 0:14:44 | 0:14:48 | |
What's important to remember, of course, | 0:14:50 | 0:14:52 | |
is that this electromagnet only works | 0:14:52 | 0:14:55 | |
all the time there's a current passing through it. | 0:14:55 | 0:14:58 | |
As soon as I turn off the current... | 0:14:58 | 0:15:01 | |
the magnetism disappears. | 0:15:01 | 0:15:03 | |
Early experimenters showed off this power by lifting metal weights. | 0:15:06 | 0:15:11 | |
Henry even made one big enough to lift a tonne-and-a-half of metal. | 0:15:11 | 0:15:16 | |
Impressive but not world-changing. | 0:15:16 | 0:15:19 | |
But place that magnet much further away, at the end of a wire, | 0:15:19 | 0:15:23 | |
and suddenly you can make something happen at your command. | 0:15:23 | 0:15:27 | |
In an instant. | 0:15:27 | 0:15:29 | |
This ability to control a magnet at a distance, | 0:15:33 | 0:15:38 | |
is one of the most useful things we've ever discovered. | 0:15:38 | 0:15:41 | |
If electricity can be made visible | 0:15:44 | 0:15:46 | |
a long way away from the original source of power, | 0:15:46 | 0:15:49 | |
then you've got a source of instantaneous communication. | 0:15:49 | 0:15:52 | |
By the middle of the 1840s, | 0:15:57 | 0:15:59 | |
Samuel Morse had developed a messaging system, | 0:15:59 | 0:16:02 | |
based on how long an electrical circuit was switched on or off. | 0:16:02 | 0:16:08 | |
A long pulse of current for a dash, a short burst for a dot. | 0:16:08 | 0:16:13 | |
This allowed messages to be sent and received by using a simple code. | 0:16:13 | 0:16:18 | |
Contemporary early Victorian commentators | 0:16:19 | 0:16:22 | |
reflect on the fact that electricity | 0:16:22 | 0:16:25 | |
and the telegraph is literally making their world a smaller place. | 0:16:25 | 0:16:29 | |
You very often get a sort of rhetoric throughout the 19th century, | 0:16:29 | 0:16:33 | |
when people are talking about the telegraph, | 0:16:33 | 0:16:36 | |
about how more communication, more understanding, | 0:16:36 | 0:16:40 | |
will render war obsolete, | 0:16:40 | 0:16:43 | |
because we'll all understand each other better. | 0:16:43 | 0:16:46 | |
I mean, retrospectively, it seems...hopelessly utopian. | 0:16:46 | 0:16:50 | |
By the 1850s, | 0:16:54 | 0:16:55 | |
Europe and America were criss-crossed | 0:16:55 | 0:16:59 | |
with land-based telegraph wires, | 0:16:59 | 0:17:01 | |
but the dream of instant global communication | 0:17:01 | 0:17:04 | |
was frustratingly out of reach. | 0:17:04 | 0:17:06 | |
This was because there was still no cable | 0:17:06 | 0:17:09 | |
capable of carrying messages | 0:17:09 | 0:17:11 | |
between two of the greatest powers on earth - | 0:17:11 | 0:17:16 | |
Britain and America. | 0:17:16 | 0:17:19 | |
Many experts were convinced | 0:17:19 | 0:17:21 | |
that a working Atlantic cable was impossible. | 0:17:21 | 0:17:24 | |
But those who disagreed knew that if they could solve this problem, | 0:17:24 | 0:17:28 | |
it could make them serious money. | 0:17:28 | 0:17:30 | |
And in the 1850s, American businessmen and British engineers | 0:17:30 | 0:17:34 | |
joined forces to prove this could be done. | 0:17:34 | 0:17:38 | |
Attempt after attempt ended in disaster. | 0:17:41 | 0:17:44 | |
The heavy cables kept snapping in heavy seas and storms. | 0:17:44 | 0:17:49 | |
Finally, on 29th July 1858, | 0:17:51 | 0:17:55 | |
two parts of a cable were spliced together in mid-Atlantic. | 0:17:55 | 0:18:00 | |
You see, a single cable was simply too big to be carried by one ship. | 0:18:00 | 0:18:04 | |
Then one end was taken to Newfoundland, | 0:18:04 | 0:18:07 | |
and the other end to south-west Ireland. | 0:18:07 | 0:18:10 | |
Six days later, the first direct link | 0:18:10 | 0:18:13 | |
between the two most powerful nations in the world was in place. | 0:18:13 | 0:18:18 | |
The project was hailed a huge success | 0:18:18 | 0:18:22 | |
and a formal message of congratulations | 0:18:22 | 0:18:25 | |
was sent from Queen Victoria to President Buchanan. | 0:18:25 | 0:18:29 | |
But before the celebrations were over, | 0:18:29 | 0:18:33 | |
things started to go very wrong. | 0:18:33 | 0:18:36 | |
This is Chief Engineer Bright's original notebook. | 0:18:36 | 0:18:40 | |
You can see here Queen Victoria's original message. | 0:18:40 | 0:18:45 | |
Now, it's only 98 words long, but it took 16 hours to transmit. | 0:18:45 | 0:18:50 | |
The telegraph operators on the other side found it very hard | 0:18:51 | 0:18:55 | |
to decipher the message. | 0:18:55 | 0:18:57 | |
The electrical signals they were receiving | 0:18:57 | 0:18:59 | |
were blurred and distorted | 0:18:59 | 0:19:01 | |
and they kept asking for words to be repeated over and over again. | 0:19:01 | 0:19:05 | |
So you can see here, | 0:19:05 | 0:19:06 | |
"Repeat after sending. Waiting to receive, no signals." | 0:19:06 | 0:19:11 | |
Clearly, transmitting across the Atlantic | 0:19:11 | 0:19:14 | |
wasn't going to be as straightforward as people had hoped. | 0:19:14 | 0:19:18 | |
Over the next few days, several hundred messages were exchanged, | 0:19:20 | 0:19:25 | |
but those arriving in Newfoundland | 0:19:25 | 0:19:28 | |
became almost impossible to decipher, | 0:19:28 | 0:19:31 | |
just a jumbled mess of dots and dashes. | 0:19:31 | 0:19:34 | |
There was a serious problem with the cable and it was getting worse. | 0:19:34 | 0:19:38 | |
Well, the 1858 cable was never fully repaired, | 0:19:38 | 0:19:43 | |
and the end finally came when British engineer Wildman Whitehouse | 0:19:43 | 0:19:49 | |
mistakenly believed that by increasing the signal voltage | 0:19:49 | 0:19:54 | |
he could force the messages through to Newfoundland. | 0:19:54 | 0:19:56 | |
The cable simply stopped working altogether. | 0:19:56 | 0:19:59 | |
At the time, increasing the voltage | 0:20:05 | 0:20:07 | |
by using more powerful batteries made sense. | 0:20:07 | 0:20:11 | |
Most experts believed electric current | 0:20:11 | 0:20:15 | |
flowed through a cable, like a fluid in a pipe. | 0:20:15 | 0:20:18 | |
Increasing the voltage was the equivalent | 0:20:18 | 0:20:21 | |
of increasing the pressure in the system - | 0:20:21 | 0:20:24 | |
forcing the current through to the other end. | 0:20:24 | 0:20:28 | |
But the telegraph was actually carrying pulses, | 0:20:28 | 0:20:31 | |
or ripples of currents along the cable, | 0:20:31 | 0:20:33 | |
not a continuous stream. | 0:20:33 | 0:20:36 | |
And over long distances, | 0:20:36 | 0:20:38 | |
these pulses were becoming distorted, | 0:20:38 | 0:20:41 | |
making it difficult to tell what was a short dot | 0:20:41 | 0:20:45 | |
and which was a longer dash. | 0:20:45 | 0:20:48 | |
By studying the effectiveness of underwater cabling, | 0:20:48 | 0:20:52 | |
scientists were beginning to understand | 0:20:52 | 0:20:54 | |
that electric current didn't always flow like water, | 0:20:54 | 0:20:59 | |
but was also creating invisible electromagnetic waves, or ripples. | 0:20:59 | 0:21:05 | |
And it's this breakthrough that would lead to a new branch | 0:21:05 | 0:21:09 | |
of research into the electromagnetic spectrum, | 0:21:09 | 0:21:12 | |
and solve the problems of the Atlantic telegraph. | 0:21:12 | 0:21:17 | |
In effect, the Transatlantic Cable | 0:21:18 | 0:21:20 | |
was a giant, ambitious, hugely expensive experiment. | 0:21:20 | 0:21:26 | |
The failure of science to keep pace with technology had been exposed. | 0:21:26 | 0:21:32 | |
And a new, more theoretical and, for me, much more exciting approach | 0:21:32 | 0:21:38 | |
to understanding electricity began to unfold. | 0:21:38 | 0:21:43 | |
Armed with this new understanding of how electric pulses | 0:21:47 | 0:21:51 | |
actually moved along the cable, improvements were made | 0:21:51 | 0:21:55 | |
to its composition, design, and how it was laid. | 0:21:55 | 0:21:59 | |
It would take another eight years of scientists and engineers | 0:22:02 | 0:22:06 | |
working together before a working cable was finally put in place. | 0:22:06 | 0:22:11 | |
And on Friday 27th July 1866, | 0:22:13 | 0:22:17 | |
a message was sent from Ireland to Newfoundland. | 0:22:17 | 0:22:21 | |
Clear and crisp. | 0:22:21 | 0:22:23 | |
"A treaty of peace has been signed between Austria and Prussia." | 0:22:25 | 0:22:30 | |
At last, the dream of instant transatlantic communication | 0:22:31 | 0:22:35 | |
had become a reality. | 0:22:35 | 0:22:36 | |
The success of the 1866 cable makes the world a smaller place. | 0:22:39 | 0:22:45 | |
Yet again. | 0:22:45 | 0:22:47 | |
The change from a world where it took days or weeks or months | 0:22:49 | 0:22:54 | |
for information to travel, | 0:22:54 | 0:22:56 | |
to a world in which information took seconds or minutes to travel - | 0:22:56 | 0:23:02 | |
it is far more profound | 0:23:02 | 0:23:03 | |
than almost anything that's taken place during my lifetime. | 0:23:03 | 0:23:07 | |
The invention of the telegraph changed ordinary people's lives. | 0:23:09 | 0:23:14 | |
But it would be the breakthroughs | 0:23:14 | 0:23:16 | |
in how we used continuously flowing electric current | 0:23:16 | 0:23:20 | |
that would have an even greater impact. | 0:23:20 | 0:23:23 | |
Because inventors were developing a new way of using electricity. | 0:23:25 | 0:23:30 | |
To make something every person in the world would want - | 0:23:34 | 0:23:39 | |
electric light. | 0:23:39 | 0:23:42 | |
Until the 19th century, | 0:23:45 | 0:23:48 | |
we only knew of one way to make our own light - burn things. | 0:23:48 | 0:23:54 | |
And by the middle of the 19th century, | 0:24:02 | 0:24:05 | |
we'd perfected a very effective way of lighting our homes - | 0:24:05 | 0:24:09 | |
using gas. | 0:24:09 | 0:24:10 | |
A typical British home in the 1860s would have been lit like this - | 0:24:15 | 0:24:19 | |
highly-flammable gas | 0:24:19 | 0:24:20 | |
would have been pumped directly into people's houses | 0:24:20 | 0:24:24 | |
through a network of pipes. | 0:24:24 | 0:24:26 | |
But these gas lamps were too dull for large outdoor areas. | 0:24:29 | 0:24:34 | |
So railway stations and streets began to be lit | 0:24:34 | 0:24:38 | |
from a more powerful source - electric arc lights. | 0:24:38 | 0:24:42 | |
The first arc lights were demonstrated | 0:24:44 | 0:24:47 | |
by Michael Faraday's mentor, Sir Humphry Davy, | 0:24:47 | 0:24:51 | |
at the Royal institution as early as 1808, | 0:24:51 | 0:24:53 | |
and they worked by passing a continuous spark of electricity | 0:24:53 | 0:24:58 | |
across two carbon rods. | 0:24:58 | 0:25:01 | |
But their intense white glow was just too bright for people's homes. | 0:25:04 | 0:25:09 | |
For an electric light to compete with gas, | 0:25:09 | 0:25:12 | |
it would need to be subdivided into many smaller, | 0:25:12 | 0:25:15 | |
less powerful and more gentle lamps. | 0:25:15 | 0:25:19 | |
Whoever succeeded in bringing electric light | 0:25:19 | 0:25:22 | |
to every home in the land was guaranteed fame and fortune. | 0:25:22 | 0:25:26 | |
And by the early 1880s, the most famous, most prodigious, | 0:25:26 | 0:25:31 | |
most fiercely competitive inventor in the world | 0:25:31 | 0:25:34 | |
had taken on the challenge. | 0:25:34 | 0:25:36 | |
The American, Thomas Alva Edison. | 0:25:36 | 0:25:41 | |
For Edison, invention was a passion, | 0:25:42 | 0:25:45 | |
it's what he loved doing. He loved being in the laboratory. | 0:25:45 | 0:25:49 | |
The first thing that drove that passion is that | 0:25:49 | 0:25:52 | |
it was a lot of fun for Edison. That was the thing that he found | 0:25:52 | 0:25:56 | |
most exciting, is that this was something he did well, | 0:25:56 | 0:26:00 | |
and it allowed all of his creativity to come to the fore. | 0:26:00 | 0:26:05 | |
Edison is Mr Electrical Invention. | 0:26:05 | 0:26:07 | |
He's the man they trust. | 0:26:09 | 0:26:11 | |
He's the man that they think can do anything. | 0:26:11 | 0:26:16 | |
He's also the man who has his carefully cultivated connections | 0:26:16 | 0:26:21 | |
with entrepreneurs, with people that are willing to put their cash | 0:26:21 | 0:26:26 | |
where Edison's mouth is, so to speak, | 0:26:26 | 0:26:28 | |
and back him in this sort of venture. | 0:26:28 | 0:26:31 | |
For Edison, the money was probably the least important reason. | 0:26:31 | 0:26:34 | |
For Edison, the money was important for one reason - | 0:26:34 | 0:26:37 | |
to allow him to do the next project. | 0:26:37 | 0:26:39 | |
Edison had assembled a group of young and talented engineers | 0:26:41 | 0:26:47 | |
at a cutting-edge laboratory in New Jersey, | 0:26:47 | 0:26:50 | |
26 miles from Manhattan. | 0:26:50 | 0:26:52 | |
Menlo Park would become | 0:26:54 | 0:26:56 | |
the world's first research and development facility, | 0:26:56 | 0:27:00 | |
allowing Edison's team to invent on an industrial scale. | 0:27:00 | 0:27:04 | |
They worked incredible hours, you know, | 0:27:06 | 0:27:09 | |
one of them talked about how he hardly ever saw his children | 0:27:09 | 0:27:12 | |
cos he was in the lab all the time. | 0:27:12 | 0:27:14 | |
But they knew they were in the midst of something really important. | 0:27:20 | 0:27:24 | |
That if Edison succeeded, | 0:27:24 | 0:27:25 | |
if they succeeded with Edison, their futures were secure. | 0:27:25 | 0:27:28 | |
Edison's dream was to bring electric light to every home in the land, | 0:27:35 | 0:27:40 | |
and with his team of engineers behind him, | 0:27:40 | 0:27:42 | |
and the vision of an electric future ahead, he launched his campaign. | 0:27:42 | 0:27:47 | |
The race to bring electric light to the world was to play out | 0:27:49 | 0:27:53 | |
in the great cities of the time - New York, Paris, London. | 0:27:53 | 0:27:58 | |
Edison's Menlo Park team set about developing | 0:27:59 | 0:28:03 | |
a totally different form of electric lamp - | 0:28:03 | 0:28:07 | |
the incandescent light bulb. | 0:28:07 | 0:28:09 | |
In fact, Edison's light bulb design wasn't all that new. Or unique. | 0:28:10 | 0:28:16 | |
French, Russian, Belgian and British inventors | 0:28:16 | 0:28:20 | |
had been perfecting similar bulbs for over 40 years. | 0:28:20 | 0:28:24 | |
And one of them, an Englishman, Joseph Swan, | 0:28:24 | 0:28:28 | |
had been developing his own version of an incandescent lamp. | 0:28:28 | 0:28:33 | |
Both Swan and Edison's light bulbs | 0:28:33 | 0:28:35 | |
worked by passing an electric current through a filament. | 0:28:35 | 0:28:38 | |
Now, a filament is a material in which the electric current | 0:28:38 | 0:28:43 | |
flows through with more difficulty than it does | 0:28:43 | 0:28:46 | |
through the copper wire in the rest of the circuit. | 0:28:46 | 0:28:51 | |
And it relies on the idea of resistance. | 0:28:51 | 0:28:53 | |
Inside this jar, I have a filament made out of ordinary pencil lead, | 0:28:53 | 0:28:57 | |
and we can see what happens as I pass a current through it. | 0:28:57 | 0:29:01 | |
Down at the atomic scale, | 0:29:03 | 0:29:05 | |
the atoms in the filament impede the flow of electricity. | 0:29:05 | 0:29:08 | |
So it takes more energy to force it through, | 0:29:08 | 0:29:12 | |
and this energy is deposited in the filament as heat. | 0:29:12 | 0:29:15 | |
Now, as it heats up, its resistance goes up, | 0:29:15 | 0:29:18 | |
which again raises its temperature, until it glows white-hot. | 0:29:18 | 0:29:23 | |
Now, one of the first materials | 0:29:26 | 0:29:28 | |
Edison used for his filaments was platinum. | 0:29:28 | 0:29:31 | |
With its relatively high melting point, | 0:29:35 | 0:29:38 | |
platinum could be heated | 0:29:38 | 0:29:40 | |
to a white-hot temperature without melting. | 0:29:40 | 0:29:43 | |
It could also be stretched into thin strands, and the thinner the strand, | 0:29:43 | 0:29:48 | |
the more resistance it offered to the current passing through it. | 0:29:48 | 0:29:53 | |
But platinum was expensive and didn't offer enough resistance. | 0:29:53 | 0:29:57 | |
The race was on to find a better alternative | 0:29:59 | 0:30:03 | |
and the solution came when the Menlo Park team | 0:30:03 | 0:30:07 | |
switched to a method Swan was also developing, | 0:30:07 | 0:30:11 | |
using a vacuum to stop cheaper carbon filaments | 0:30:11 | 0:30:14 | |
from burning up too quickly. | 0:30:14 | 0:30:16 | |
Edison and Swan tested all kinds of different materials | 0:30:18 | 0:30:21 | |
for their filaments - | 0:30:21 | 0:30:23 | |
everything from raw silk and parchment to cork. | 0:30:23 | 0:30:27 | |
Edison even tested his engineers' beard hair. | 0:30:27 | 0:30:31 | |
Eventually, he settled on bamboo fibre, | 0:30:31 | 0:30:34 | |
while Swan used a treated cotton thread. | 0:30:34 | 0:30:37 | |
Edison and Swan's light bulb designs were very similar. | 0:30:38 | 0:30:43 | |
Eventually they came to an agreement and went into partnership | 0:30:43 | 0:30:46 | |
to sell light bulbs in the UK. | 0:30:46 | 0:30:49 | |
Today, many people still believe that Edison alone | 0:30:49 | 0:30:53 | |
invented the light bulb, whilst Swan has become a footnote in history. | 0:30:53 | 0:30:58 | |
But his incandescent bulb was only part of Edison's strategy. | 0:31:05 | 0:31:10 | |
He'd also invented an entire electrical system of sockets, | 0:31:10 | 0:31:16 | |
cables, and meters to go with it. | 0:31:16 | 0:31:17 | |
And, being a brilliant businessman, | 0:31:17 | 0:31:20 | |
he'd developed a ground-breaking new way of distributing electricity. | 0:31:20 | 0:31:26 | |
Edison knew that the key to making money from his system | 0:31:26 | 0:31:30 | |
was to generate the electricity in a central station, | 0:31:30 | 0:31:33 | |
and then sell it to as many customers as possible. | 0:31:33 | 0:31:37 | |
It seems obvious to us now, but until then, | 0:31:37 | 0:31:39 | |
anyone who wanted to use electricity | 0:31:39 | 0:31:41 | |
had to have their own noisy generator to make it. | 0:31:41 | 0:31:45 | |
Edison's ambition was huge - | 0:31:47 | 0:31:50 | |
he wanted to light the fastest-growing | 0:31:50 | 0:31:53 | |
and most exciting city in the world. | 0:31:53 | 0:31:56 | |
New York. | 0:32:00 | 0:32:01 | |
In the summer of 1882, Edison stood in a unique position, | 0:32:03 | 0:32:07 | |
at the centre of 19th century science and invention. | 0:32:07 | 0:32:11 | |
He'd patented a cutting-edge incandescent light bulb, | 0:32:11 | 0:32:16 | |
he'd amassed an unprecedented knowledge of electrical engineering. | 0:32:16 | 0:32:20 | |
And above all, | 0:32:20 | 0:32:21 | |
he'd cultivated a reputation among the American public | 0:32:21 | 0:32:24 | |
of being such a genius inventor, | 0:32:24 | 0:32:27 | |
that journalists hung on his every word, | 0:32:27 | 0:32:29 | |
and the financial muscle of Wall Street | 0:32:29 | 0:32:32 | |
was quick to throw itself behind his new ideas. | 0:32:32 | 0:32:36 | |
His vision, to electrify Manhattan, | 0:32:36 | 0:32:38 | |
and then, of course, the rest of the world, | 0:32:38 | 0:32:41 | |
was seemingly within his grasp. | 0:32:41 | 0:32:44 | |
Because Edison and his team | 0:32:49 | 0:32:50 | |
were about to launch their most expensive and risky project yet - | 0:32:50 | 0:32:56 | |
America's first power station, | 0:32:56 | 0:32:58 | |
generating continuous direct current. | 0:32:58 | 0:33:01 | |
Just before 3pm on the 4th September 1882, Thomas Edison, | 0:33:06 | 0:33:10 | |
surrounded by a gaggle of bankers, dignitaries and reporters, | 0:33:10 | 0:33:14 | |
entered JP Morgan's building, right behind me, | 0:33:14 | 0:33:17 | |
flicked one of the Edison-patented switches, | 0:33:17 | 0:33:20 | |
and 100 of his incandescent bulbs began to glow. | 0:33:20 | 0:33:26 | |
Turning to a nearby journalist, he said, | 0:33:26 | 0:33:28 | |
"I have accomplished all that I've promised." | 0:33:28 | 0:33:32 | |
Half a mile away on Pearl Street, Edison's new power station, | 0:33:35 | 0:33:39 | |
costing half a million dollars and four years of hard work, | 0:33:39 | 0:33:44 | |
had sprung into life. | 0:33:44 | 0:33:45 | |
The current surged through buried cables, | 0:33:47 | 0:33:49 | |
stretching out in each direction. | 0:33:49 | 0:33:53 | |
Of course it might seem obvious to us now, | 0:33:53 | 0:33:56 | |
but in New York back in the early 1880s, | 0:33:56 | 0:33:59 | |
the idea of burying electric cables underground | 0:33:59 | 0:34:02 | |
seemed like an unnecessary expense. | 0:34:02 | 0:34:05 | |
This street would have been criss-crossed | 0:34:05 | 0:34:08 | |
with hundreds of cables, used for telegraphs, | 0:34:08 | 0:34:11 | |
telephones and arc street lighting. | 0:34:11 | 0:34:13 | |
Looking up, you'd have seen a tangled mass of black spaghetti | 0:34:13 | 0:34:18 | |
blocking out the light. | 0:34:18 | 0:34:20 | |
Edison knew this dangerous situation had to change, | 0:34:20 | 0:34:24 | |
and for him to make as much money as he could, | 0:34:24 | 0:34:29 | |
electricity needed rebranding. It had to be considered safe. | 0:34:29 | 0:34:33 | |
So Edison is arguing both for the greater safety | 0:34:33 | 0:34:37 | |
of his DC low voltage system, and for underground lines. | 0:34:37 | 0:34:42 | |
He can argue that he has a much safer system | 0:34:42 | 0:34:45 | |
than electric arc light for streets, | 0:34:45 | 0:34:49 | |
or gas lighting for indoor lighting. | 0:34:49 | 0:34:52 | |
He doesn't have to worry about fires, or electrocution, | 0:34:52 | 0:34:56 | |
that all of this is much safer | 0:34:56 | 0:34:57 | |
because of the system he's created with this underground system. | 0:34:57 | 0:35:00 | |
Burying every cable was not only very expensive | 0:35:03 | 0:35:06 | |
but was a logistical nightmare, | 0:35:06 | 0:35:09 | |
because this was one of the busiest square miles in the world. | 0:35:09 | 0:35:13 | |
Edison chose this area for a reason. | 0:35:13 | 0:35:16 | |
Wall Street. | 0:35:16 | 0:35:18 | |
Rich, important, influential. | 0:35:18 | 0:35:21 | |
Because for Edison's system to make money, | 0:35:21 | 0:35:24 | |
all these wealthy customers | 0:35:24 | 0:35:26 | |
had to be within a mile of his power station. | 0:35:26 | 0:35:29 | |
And this was because Edison calculated | 0:35:32 | 0:35:35 | |
the thickest cable he could afford | 0:35:35 | 0:35:37 | |
would only carry an adequate amount of his continuous direct current | 0:35:37 | 0:35:42 | |
to customers within this range. | 0:35:42 | 0:35:46 | |
This was a huge leap forward | 0:35:46 | 0:35:49 | |
because, for the first time, | 0:35:49 | 0:35:51 | |
dozens of customers could be supplied by just one power station. | 0:35:51 | 0:35:56 | |
But there was a big problem. | 0:35:56 | 0:35:58 | |
Edison's network could never be economical in lighting | 0:35:58 | 0:36:01 | |
America's new suburbs. | 0:36:01 | 0:36:04 | |
They just didn't have the concentration of customers | 0:36:04 | 0:36:07 | |
needed to make building these expensive power stations worthwhile. | 0:36:07 | 0:36:11 | |
Had we stuck with Edison's way | 0:36:12 | 0:36:14 | |
of generating and distributing electricity, | 0:36:14 | 0:36:17 | |
the world would be a very different place. | 0:36:17 | 0:36:20 | |
We'd have to have power stations scattered around | 0:36:21 | 0:36:25 | |
no more than a mile apart, even in the centres of our towns and cities. | 0:36:25 | 0:36:30 | |
And it would be extraordinarily expensive to even provide power | 0:36:30 | 0:36:34 | |
for smaller communities. | 0:36:34 | 0:36:36 | |
But someone who held the answers to these problems | 0:36:39 | 0:36:43 | |
was about to enter the story. | 0:36:43 | 0:36:45 | |
Someone who would help create the modern world | 0:36:45 | 0:36:49 | |
and who'd play an integral part in one of the biggest fall-outs | 0:36:49 | 0:36:53 | |
in scientific history. | 0:36:53 | 0:36:55 | |
His name was Nikola Tesla | 0:36:55 | 0:36:57 | |
and he was right under Edison's nose. | 0:36:57 | 0:37:00 | |
Nikola Tesla was a Serbian inventor | 0:37:06 | 0:37:10 | |
who was born in Croatia | 0:37:10 | 0:37:12 | |
and who worked for Edison briefly | 0:37:12 | 0:37:14 | |
after arriving in New York at the age of 28. | 0:37:14 | 0:37:18 | |
European, introverted, a deep thinker, | 0:37:18 | 0:37:22 | |
he was everything Edison wasn't. | 0:37:22 | 0:37:26 | |
Edison and Tesla could not be more different | 0:37:26 | 0:37:28 | |
in the way they handled their self, appearance, and their manners, | 0:37:28 | 0:37:32 | |
and the way that they constructed a public image for themselves. | 0:37:32 | 0:37:35 | |
Edison couldn't care less about the clothes he had on | 0:37:35 | 0:37:38 | |
and if he spilt chemicals on his good Sunday suit, | 0:37:38 | 0:37:41 | |
then he spilt chemicals on his good Sunday suit. | 0:37:41 | 0:37:43 | |
He was, you know, basically, a very kind of slovenly guy. | 0:37:43 | 0:37:48 | |
Tesla, on the other hand, | 0:37:48 | 0:37:50 | |
even as a young man in his mid 20s, is thinking about his appearance, | 0:37:50 | 0:37:54 | |
how he comes across to people. | 0:37:54 | 0:37:56 | |
So he cares about his clothes, his manner. | 0:37:56 | 0:37:58 | |
Indeed, he even cares about how his photograph, | 0:37:58 | 0:38:02 | |
his portraits are taken, | 0:38:02 | 0:38:03 | |
and he always wants to make sure he has a nice, three-quarter profile | 0:38:03 | 0:38:07 | |
so you don't see the fact that he has a bit of a pointy chin. | 0:38:07 | 0:38:10 | |
The life and death of Nikola Tesla | 0:38:12 | 0:38:15 | |
is one of the most fascinating yet tragic stories | 0:38:15 | 0:38:19 | |
of scientific brilliance, cut-throat business, | 0:38:19 | 0:38:23 | |
and shocking public relations stunts. | 0:38:23 | 0:38:26 | |
The American public may have been wowed | 0:38:29 | 0:38:32 | |
by Edison's new direct current power stations, | 0:38:32 | 0:38:35 | |
but Tesla was less impressed. | 0:38:35 | 0:38:37 | |
He had a dream electricity could be transmitted across entire cities. | 0:38:37 | 0:38:43 | |
Or even nations. | 0:38:43 | 0:38:45 | |
And he believed he knew how it could be done - | 0:38:45 | 0:38:48 | |
by using a different type of electric current. | 0:38:48 | 0:38:53 | |
Electrical experts knew that the smaller the current | 0:38:57 | 0:39:01 | |
sent down a cable, the smaller the losses in it through resistance. | 0:39:01 | 0:39:06 | |
And so the longer the cable could be. | 0:39:06 | 0:39:09 | |
Tesla proposed using a method of transmitting electricity | 0:39:09 | 0:39:14 | |
where the currents could be lowered without a fall | 0:39:14 | 0:39:17 | |
in the amount of electrical power at the other end. | 0:39:17 | 0:39:20 | |
It was called alternating current. | 0:39:20 | 0:39:22 | |
Alternating current is exactly that. | 0:39:24 | 0:39:27 | |
It's an electric current that alternates | 0:39:27 | 0:39:30 | |
between moving in one direction, | 0:39:30 | 0:39:32 | |
then the opposite direction, very quickly. | 0:39:32 | 0:39:35 | |
As opposed to a direct current, which moves only in one direction. | 0:39:35 | 0:39:40 | |
Tesla was interested in alternating current because, | 0:39:40 | 0:39:43 | |
like other electrical engineers in the late 1880s, | 0:39:43 | 0:39:47 | |
he realised that as you raise the voltage of any current | 0:39:47 | 0:39:51 | |
that you transmit from point A to point B, | 0:39:51 | 0:39:54 | |
it's going to be more efficient to have a higher voltage. | 0:39:54 | 0:39:58 | |
And since the amount of electric power in a cable is its voltage | 0:39:59 | 0:40:03 | |
multiplied by its current, increasing the voltage, | 0:40:03 | 0:40:07 | |
meant the current in the cables could be reduced, | 0:40:07 | 0:40:10 | |
and so losses due to resistance would be less. | 0:40:10 | 0:40:14 | |
However, you don't want very high voltages | 0:40:14 | 0:40:17 | |
on the order of, say, 20,000 volts coming into your home. | 0:40:17 | 0:40:21 | |
So you need to step down the current | 0:40:21 | 0:40:22 | |
that is being transmitted over distance into your home. | 0:40:22 | 0:40:25 | |
And to do that, you need a converter or transformer. | 0:40:25 | 0:40:29 | |
Alternating current allows you to use a transformer | 0:40:29 | 0:40:34 | |
to make that switch from the high transmission voltage | 0:40:34 | 0:40:37 | |
to the lower voltage you're going to use at consumption. | 0:40:37 | 0:40:40 | |
Perfecting the technology to transmit electricity | 0:40:42 | 0:40:46 | |
hundreds of miles from where it was generated | 0:40:46 | 0:40:50 | |
would mark a huge step towards the modern world. | 0:40:50 | 0:40:53 | |
And a wealthy industrial entrepreneur | 0:40:54 | 0:40:57 | |
was already developing the solution. | 0:40:57 | 0:41:00 | |
His name was George Westinghouse. | 0:41:00 | 0:41:03 | |
Westinghouse believed alternating currents was the future, | 0:41:03 | 0:41:06 | |
but it had a big drawback. | 0:41:06 | 0:41:10 | |
While it was fine for electric light, | 0:41:10 | 0:41:12 | |
unlike direct current, | 0:41:12 | 0:41:14 | |
there was no practical motor that could run on it. | 0:41:14 | 0:41:18 | |
And no-one believed there ever would be. | 0:41:18 | 0:41:21 | |
Apart from Nikola Tesla. | 0:41:21 | 0:41:23 | |
Tesla, as an inventor, liked to say | 0:41:24 | 0:41:26 | |
that the first thing you need to do is not to build something, | 0:41:26 | 0:41:31 | |
but to imagine it, to think it through, to plan it. | 0:41:31 | 0:41:34 | |
And he had what modern-day psychologists would call | 0:41:34 | 0:41:38 | |
an eidetic memory. He could basically | 0:41:38 | 0:41:40 | |
remember everything that he saw | 0:41:40 | 0:41:42 | |
and then visualise it in three dimensions. | 0:41:42 | 0:41:45 | |
And they often say people that have this skill | 0:41:45 | 0:41:48 | |
see it about an arm's length away, | 0:41:48 | 0:41:50 | |
out here, and they see it in three dimensions in that space. | 0:41:50 | 0:41:53 | |
And all the indications are that Tesla had that ability. | 0:41:53 | 0:41:56 | |
This is a Tesla egg. | 0:42:00 | 0:42:04 | |
It's a replica of the one Tesla used | 0:42:06 | 0:42:08 | |
to demonstrate his greatest breakthrough | 0:42:08 | 0:42:11 | |
and one of the most important inventions of all time. | 0:42:11 | 0:42:16 | |
It showed how rotary movement | 0:42:16 | 0:42:18 | |
can be produced directly from an alternating current. | 0:42:18 | 0:42:22 | |
Crucially, one that could be generated thousands of miles away. | 0:42:22 | 0:42:26 | |
This was something that had never been done before. | 0:42:26 | 0:42:30 | |
When Tesla was working on the alternating current motor, | 0:42:38 | 0:42:41 | |
he was thinking big. | 0:42:41 | 0:42:43 | |
He was not just tinkering with one component | 0:42:43 | 0:42:46 | |
of the motor and saying, "Gee, if I can make that a little bit better, | 0:42:46 | 0:42:49 | |
"it will work out." He's actually thinking about | 0:42:49 | 0:42:52 | |
an entire system that involves the generator, | 0:42:52 | 0:42:56 | |
the wires to the motor | 0:42:56 | 0:42:58 | |
and the motor itself. He's a complete maverick, | 0:42:58 | 0:43:00 | |
thinking outside the box, | 0:43:00 | 0:43:03 | |
doing things very differently to his fellow inventors. | 0:43:03 | 0:43:06 | |
Tesla's solution was ingenious. | 0:43:06 | 0:43:09 | |
He fed more than one alternating current into his motor | 0:43:09 | 0:43:13 | |
and timed them so that they followed in sequence with each other. | 0:43:13 | 0:43:17 | |
The first alternating current | 0:43:17 | 0:43:20 | |
energised a coil of wire inside the motor, | 0:43:20 | 0:43:24 | |
creating an electromagnetic field | 0:43:24 | 0:43:26 | |
which attracted the motor's central moving part to it | 0:43:26 | 0:43:30 | |
and then faded. | 0:43:30 | 0:43:32 | |
The second overlapping current fed the next coil, | 0:43:32 | 0:43:36 | |
dragging the moving part around further, before it faded. | 0:43:36 | 0:43:40 | |
And the same for the third coil and the fourth. | 0:43:40 | 0:43:43 | |
The result was a revolving magnetic field, | 0:43:43 | 0:43:47 | |
strong enough to make the motor, | 0:43:47 | 0:43:50 | |
or in this case his egg, spin. | 0:43:50 | 0:43:52 | |
Tesla designed an entire electrical system around this | 0:43:52 | 0:43:56 | |
called polyphase transmission. | 0:43:56 | 0:43:59 | |
This meant a noisy and smelly power station, | 0:43:59 | 0:44:02 | |
generating lots of useful alternating current, | 0:44:02 | 0:44:05 | |
could now be situated away from populated areas. | 0:44:05 | 0:44:09 | |
And for the first time you can build large power stations | 0:44:10 | 0:44:13 | |
wherever you want. On the edge of town, | 0:44:13 | 0:44:15 | |
or a waterfall like Niagara, | 0:44:15 | 0:44:17 | |
and distribute the power over long distances, | 0:44:17 | 0:44:20 | |
and serve all the people | 0:44:20 | 0:44:22 | |
in a major city or metropolitan centre. | 0:44:22 | 0:44:25 | |
Tesla's breakthrough was the last piece of the jigsaw, | 0:44:25 | 0:44:30 | |
but he still had to convince the world | 0:44:30 | 0:44:33 | |
that his solution was better | 0:44:33 | 0:44:35 | |
than the direct current method championed by Edison. | 0:44:35 | 0:44:39 | |
Edison continued to roll out his direct current system, | 0:44:43 | 0:44:48 | |
building power stations across New York state. | 0:44:48 | 0:44:51 | |
But then Tesla met George Westinghouse - | 0:44:55 | 0:44:59 | |
the man who could make his dreams into a reality. | 0:44:59 | 0:45:03 | |
In July 1888, Westinghouse made an offer for Tesla's patents, | 0:45:05 | 0:45:10 | |
which has become part of the mystery and folklore | 0:45:10 | 0:45:13 | |
surrounding the whole Nikola Tesla story, | 0:45:13 | 0:45:16 | |
where it's difficult to separate fact from fiction. | 0:45:16 | 0:45:20 | |
Tesla was paid 75,000 for his alternating current patents | 0:45:21 | 0:45:26 | |
and offered 2.50 | 0:45:26 | 0:45:29 | |
for every horse power his motors would generate. | 0:45:29 | 0:45:32 | |
This should have guaranteed him vast wealth | 0:45:32 | 0:45:35 | |
for the rest of his life but that isn't what happened. | 0:45:35 | 0:45:39 | |
It's clear to us now that at the time, | 0:45:42 | 0:45:44 | |
the AC system was a much better method | 0:45:44 | 0:45:47 | |
of transmitting electric power. | 0:45:47 | 0:45:49 | |
And you'd think that with Tesla's breakthroughs, | 0:45:49 | 0:45:52 | |
nothing could stand in the way of the success of AC over DC. | 0:45:52 | 0:45:57 | |
But one man still believed totally | 0:45:57 | 0:46:00 | |
in his direct current inventions, | 0:46:00 | 0:46:02 | |
From the filaments of the bulbs to the switches, | 0:46:02 | 0:46:06 | |
sockets and generators, | 0:46:06 | 0:46:07 | |
and he wasn't about to waste millions of dollars | 0:46:07 | 0:46:11 | |
on changing them. | 0:46:11 | 0:46:13 | |
Edison. | 0:46:13 | 0:46:16 | |
The battle lines were drawn. | 0:46:17 | 0:46:19 | |
Westinghouse and Tesla went toe-to-toe with Edison | 0:46:19 | 0:46:23 | |
for New York's lucrative lighting contracts. | 0:46:23 | 0:46:26 | |
Two completely different systems | 0:46:26 | 0:46:29 | |
battling it out for one ultimate prize - | 0:46:29 | 0:46:32 | |
the chance to light up America and then the world. | 0:46:32 | 0:46:37 | |
It would become known as the War of the Currents. | 0:46:37 | 0:46:41 | |
Both camps tried to undercut each other on cost, | 0:46:45 | 0:46:48 | |
but Edison believed his beloved direct current | 0:46:48 | 0:46:52 | |
was better than alternating current because it was safer. | 0:46:52 | 0:46:56 | |
Touching an Edison cable, with its low voltage, | 0:46:58 | 0:47:02 | |
was painful but relatively harmless. | 0:47:02 | 0:47:04 | |
Whereas alternating current cables | 0:47:04 | 0:47:06 | |
carried a much higher voltage | 0:47:06 | 0:47:10 | |
and touching them could be deadly. | 0:47:10 | 0:47:13 | |
So, what Edison was trying to do | 0:47:13 | 0:47:16 | |
was to again define his DC system as the safe system. | 0:47:16 | 0:47:22 | |
It's better than electric street arc lights, | 0:47:22 | 0:47:26 | |
it's better than gas, | 0:47:26 | 0:47:28 | |
and it's now better than high voltage AC incandescent lighting. | 0:47:28 | 0:47:31 | |
Right? It's the system that's safe. | 0:47:31 | 0:47:34 | |
You adopt the Edison system, you can be sure it's safe. | 0:47:34 | 0:47:38 | |
Edison claimed that AC | 0:47:41 | 0:47:42 | |
was a more dangerous type of current than DC | 0:47:42 | 0:47:46 | |
and he highlighted every accident to Westinghouse's workmen | 0:47:46 | 0:47:50 | |
and every fire caused by short circuits. | 0:47:50 | 0:47:53 | |
It was a potent message because in the 1880s, | 0:47:58 | 0:48:01 | |
many people were still terrified by electricity. | 0:48:01 | 0:48:05 | |
It could shock and even kill in an instant | 0:48:05 | 0:48:09 | |
and the reasons why still weren't fully understood. | 0:48:09 | 0:48:13 | |
For many, the idea of piping this invisible killer into their homes | 0:48:13 | 0:48:18 | |
was utterly ludicrous. | 0:48:18 | 0:48:19 | |
So the weapon used in the War of the Currents was fear. | 0:48:22 | 0:48:27 | |
And a little-known electrical engineer, | 0:48:31 | 0:48:34 | |
Harold P. Brown, | 0:48:34 | 0:48:36 | |
was about to take the fight against AC | 0:48:36 | 0:48:39 | |
to a whole new level. | 0:48:39 | 0:48:41 | |
It was to prove one of the most extreme | 0:48:44 | 0:48:48 | |
and negative publicity campaigns in history. | 0:48:48 | 0:48:51 | |
Brown had devised a unique and theatrical way | 0:48:51 | 0:48:56 | |
of demonstrating the deadly power of AC... | 0:48:56 | 0:48:59 | |
..and he was eager to share it with the world. | 0:49:00 | 0:49:03 | |
So, on a warm summer's evening, in July 1888, | 0:49:03 | 0:49:09 | |
he gathered together 75 of the country's | 0:49:09 | 0:49:12 | |
top electrical engineers and reporters | 0:49:12 | 0:49:15 | |
to witness a spectacle they would never forget. | 0:49:15 | 0:49:19 | |
Brown's plan was extremely macabre. | 0:49:24 | 0:49:28 | |
He'd paid a team of street urchins | 0:49:28 | 0:49:30 | |
to collect together stray dogs roaming Manhattan. | 0:49:30 | 0:49:33 | |
Out on stage, he addressed his audience. | 0:49:33 | 0:49:36 | |
"I have asked you here, gentlemen, | 0:49:36 | 0:49:39 | |
"to witness the experimental application of electricity | 0:49:39 | 0:49:44 | |
"to a number of brutes." | 0:49:44 | 0:49:47 | |
His demonstration involved electrocuting the dogs... | 0:49:48 | 0:49:52 | |
with DC and AC power, | 0:49:52 | 0:49:54 | |
in an attempt to show that AC current killed them more quickly. | 0:49:54 | 0:50:01 | |
And it wasn't just dogs. | 0:50:01 | 0:50:04 | |
Brown went on to make public spectacles of killing a calf | 0:50:04 | 0:50:08 | |
and even a horse. | 0:50:08 | 0:50:09 | |
And he moved from dogs to larger animals for a reason. | 0:50:11 | 0:50:14 | |
He wanted to show that the AC form of electricity was so dangerous | 0:50:14 | 0:50:19 | |
it could kill any large mammal, including humans. | 0:50:19 | 0:50:23 | |
Brown's animal experiments had persuaded American politicians | 0:50:32 | 0:50:38 | |
the most humane method of executing condemned criminals | 0:50:38 | 0:50:42 | |
should be with alternating current, | 0:50:42 | 0:50:44 | |
generated by Westinghouse machines. | 0:50:44 | 0:50:46 | |
Edison's lawyers even suggested a new term | 0:50:48 | 0:50:52 | |
to describe being electrocuted in this way... | 0:50:52 | 0:50:56 | |
..to be Westinghoused. | 0:50:56 | 0:50:58 | |
And at precisely 6:32, | 0:50:59 | 0:51:02 | |
on the morning of 6th August 1890, | 0:51:02 | 0:51:07 | |
a 45-year-old man, William Kemmler, | 0:51:07 | 0:51:10 | |
was strapped to a wooden chair | 0:51:10 | 0:51:12 | |
and two soaking wet electrodes | 0:51:12 | 0:51:14 | |
were carefully attached to him. | 0:51:14 | 0:51:17 | |
And as 26 officials and doctors looked on from an adjoining room, | 0:51:17 | 0:51:21 | |
Kemmler said goodbye to the prison chaplain and waited. | 0:51:21 | 0:51:25 | |
The execution of William Kemmler | 0:51:30 | 0:51:32 | |
marked the lowest point in the War of the Currents, | 0:51:32 | 0:51:36 | |
but it wouldn't quite mark the end. | 0:51:36 | 0:51:39 | |
Because Nikola Tesla was about to do something | 0:51:39 | 0:51:42 | |
that had never been seen before. | 0:51:42 | 0:51:44 | |
Something so wondrous and daring | 0:51:44 | 0:51:46 | |
that it would live on for ever in the memories of those who saw it. | 0:51:46 | 0:51:50 | |
Tesla had been developing a method | 0:52:14 | 0:52:17 | |
of generating very high frequency alternating currents | 0:52:17 | 0:52:20 | |
and on May 21st 1891, | 0:52:20 | 0:52:22 | |
at a meeting of top electrical engineers, | 0:52:22 | 0:52:25 | |
he demonstrated it. | 0:52:25 | 0:52:27 | |
In an almost magical display of awesome power and wonder, | 0:52:33 | 0:52:38 | |
and without wearing any safety chain mail or mask, | 0:52:38 | 0:52:41 | |
tens of thousands of volts, produced by a Tesla coil, | 0:52:41 | 0:52:46 | |
passed across his body and through the end of a lamp he was holding. | 0:52:46 | 0:52:51 | |
Tesla's alternating current was at such a high frequency, | 0:52:56 | 0:53:01 | |
that it passed through his body | 0:53:01 | 0:53:03 | |
without causing serious harm or even pain. | 0:53:03 | 0:53:06 | |
His demonstrations showed that if handled correctly, | 0:53:07 | 0:53:10 | |
alternating current at extremely high voltages could be safe. | 0:53:10 | 0:53:15 | |
The War of the Currents had been won, | 0:53:16 | 0:53:20 | |
by Westinghouse and Tesla. | 0:53:20 | 0:53:22 | |
In 1896, the new power station was completed at Niagara Falls, | 0:53:22 | 0:53:28 | |
using Westinghouse AC generators | 0:53:28 | 0:53:30 | |
to produce Tesla's polyphase current. | 0:53:30 | 0:53:33 | |
Finally, huge amounts of power | 0:53:33 | 0:53:36 | |
could be transmitted from the Falls, | 0:53:36 | 0:53:40 | |
to nearby Buffalo and then, a few years later, | 0:53:40 | 0:53:42 | |
the Niagara plant was providing power to New York City itself. | 0:53:42 | 0:53:48 | |
And today, almost all of the electricity generated in the world | 0:53:48 | 0:53:53 | |
is done so using Tesla's system. | 0:53:53 | 0:53:56 | |
But Tesla's story doesn't end in fame and fortune. | 0:54:03 | 0:54:07 | |
Although he went on to make significant contributions | 0:54:10 | 0:54:13 | |
to many other areas of science and invention, | 0:54:13 | 0:54:16 | |
to save George Westinghouse from ruin, after a stock market crash, | 0:54:16 | 0:54:21 | |
he gave up his claim to the royalties | 0:54:21 | 0:54:23 | |
from his polyphase inventions. | 0:54:23 | 0:54:26 | |
Nikola Tesla was a uniquely talented man and we owe him so much. | 0:54:29 | 0:54:34 | |
But he was also hugely complicated, | 0:54:34 | 0:54:36 | |
and sadly, later in life, he became more and more troubled. | 0:54:36 | 0:54:40 | |
He was fixated with the number three, | 0:54:40 | 0:54:42 | |
counting it out loud while he walked, | 0:54:42 | 0:54:45 | |
and he developed strange phobias with germs | 0:54:45 | 0:54:49 | |
and with women wearing pearl jewellery. | 0:54:49 | 0:54:52 | |
In many ways, his brilliant mind simply spun out of control. | 0:54:53 | 0:54:58 | |
As Tesla's life unravelled, | 0:55:01 | 0:55:03 | |
he withdrew from people | 0:55:03 | 0:55:05 | |
and found emotional comfort elsewhere. | 0:55:05 | 0:55:08 | |
He became obsessed with pigeons | 0:55:08 | 0:55:10 | |
and was regularly seen feeding them here in Bryant Park, | 0:55:10 | 0:55:14 | |
in the centre of Manhattan. | 0:55:14 | 0:55:16 | |
He even fell in love with one particularly unusual white bird | 0:55:16 | 0:55:20 | |
and when it died, | 0:55:20 | 0:55:22 | |
he was left heart broken. | 0:55:22 | 0:55:24 | |
As an old man, Tesla was left almost bankrupt and alone, | 0:55:35 | 0:55:40 | |
living as a semi-recluse in this hotel. | 0:55:40 | 0:55:44 | |
His last years were spent here in room 3327 of the New York Hotel, | 0:55:51 | 0:55:58 | |
sad, confused, destitute. | 0:55:58 | 0:56:00 | |
Edison went on to become an American hero | 0:56:06 | 0:56:11 | |
and his company would form part of General Electric, | 0:56:11 | 0:56:15 | |
even today one of the world's biggest multinational corporations. | 0:56:15 | 0:56:20 | |
In January 1943, the story of Nikola Tesla was coming to an end. | 0:56:21 | 0:56:28 | |
But looking out across the Manhattan skyline for the very last time, | 0:56:30 | 0:56:34 | |
he saw a sky lit up with twinkling lights, | 0:56:34 | 0:56:38 | |
and a million lives transformed by his genius. | 0:56:38 | 0:56:42 | |
The ability to generate and transmit electricity, | 0:56:59 | 0:57:02 | |
and the invention of machines to use it, | 0:57:02 | 0:57:05 | |
have changed our world in ways we couldn't possibly have imagined. | 0:57:05 | 0:57:10 | |
We can now generate billions of watts of electricity | 0:57:11 | 0:57:15 | |
every second, every hour, every day. | 0:57:15 | 0:57:18 | |
And whether we do it using coal, gas, | 0:57:19 | 0:57:23 | |
or nuclear fission, | 0:57:23 | 0:57:25 | |
power stations all rely | 0:57:25 | 0:57:27 | |
on the principles discovered and developed by Michael Faraday, | 0:57:27 | 0:57:32 | |
Nikola Tesla, | 0:57:32 | 0:57:34 | |
and all the other early electrical engineers | 0:57:34 | 0:57:37 | |
from an amazing age of invention. | 0:57:37 | 0:57:39 | |
We now take electricity for granted | 0:57:39 | 0:57:43 | |
and have forgotten how magical and mysterious a force it once was. | 0:57:43 | 0:57:49 | |
But there's something we should never forget. | 0:57:49 | 0:57:51 | |
Today, without it, the modern world would collapse around us | 0:57:51 | 0:57:56 | |
and our lives would be very, very different. | 0:57:56 | 0:58:00 | |
In the next episode, we tell of the electrical revelations | 0:58:06 | 0:58:10 | |
that led to a revolution in our understanding | 0:58:10 | 0:58:14 | |
of this amazing force. | 0:58:14 | 0:58:16 | |
To find out more about the story of electricity, | 0:58:19 | 0:58:23 | |
and to put your power knowledge to the test, | 0:58:23 | 0:58:25 | |
try the Open University's interactive energy game. | 0:58:25 | 0:58:29 | |
Go to: | 0:58:29 | 0:58:31 | |
And follow links to the Open University. | 0:58:34 | 0:58:37 | |
Subtitles by Red Bee Media Ltd 2011 | 0:58:59 | 0:59:02 | |
E-mail [email protected] | 0:59:02 | 0:59:05 |