0:00:06 > 0:00:10Electricity is one of nature's greatest forces.
0:00:12 > 0:00:14And by the middle of the 20th century,
0:00:14 > 0:00:18we'd harnessed it to light and power our modern world.
0:00:20 > 0:00:23Hundreds of years of scientific discoveries
0:00:23 > 0:00:26and inventions brought us here.
0:00:27 > 0:00:31But it would take the eccentric genius of one man
0:00:31 > 0:00:34to unlock the full potential of electrical power.
0:00:36 > 0:00:38In the winter of 1943,
0:00:38 > 0:00:40Nikola Tesla looked out
0:00:40 > 0:00:43across the Manhattan skyline
0:00:43 > 0:00:45for the very last time.
0:00:45 > 0:00:50Tesla had been born into a world powered by steam and lit by gas.
0:00:52 > 0:00:55But before his eyes, he saw a new world.
0:00:55 > 0:00:57A world transformed,
0:00:57 > 0:01:00a world powered by electricity.
0:01:00 > 0:01:01His world.
0:01:07 > 0:01:10Frail, lonely
0:01:10 > 0:01:13and still mourning the death of one of his beloved pigeons,
0:01:13 > 0:01:17this extraordinary and eccentric genius
0:01:17 > 0:01:22knew that his life's work was done and he laid back on his bed to die.
0:01:23 > 0:01:26It would be three days before anyone found his body.
0:01:38 > 0:01:42Just over 200 years ago, early scientists
0:01:42 > 0:01:47discovered electricity could be much more than simply a static charge.
0:01:47 > 0:01:52It could be made to flow in a continuous current.
0:01:58 > 0:02:01But they were about to discover something profound.
0:02:01 > 0:02:05That electricity is connected to magnetism.
0:02:06 > 0:02:10Harnessing the link between magnetism and electricity
0:02:10 > 0:02:13would completely transform the world
0:02:13 > 0:02:16and allow us to generate seemingly limitless
0:02:16 > 0:02:18amounts of electrical power.
0:02:26 > 0:02:30This is the story of how scientists and engineers
0:02:30 > 0:02:33unlocked the nature of electricity
0:02:33 > 0:02:39and then used it in an extraordinary century of innovation and invention.
0:02:39 > 0:02:42But not before one of the most shocking
0:02:42 > 0:02:47engineering rivalries in history was finally laid to rest.
0:03:03 > 0:03:06Our story begins in London,
0:03:06 > 0:03:08at the beginning of the 19th century,
0:03:08 > 0:03:12with a young man who would further our understanding of electricity
0:03:12 > 0:03:14as much as any other.
0:03:14 > 0:03:17On 29th of February, 1812,
0:03:17 > 0:03:23a 20-year-old self-educated bookbinder called Michael Faraday
0:03:23 > 0:03:27came here to the Royal institution of Great Britain.
0:03:34 > 0:03:38He was surrounded by the great and the good of the academic world.
0:03:38 > 0:03:40And he was about to listen
0:03:40 > 0:03:43to one of the greatest scientific minds of the age.
0:03:47 > 0:03:52Faraday, the son of a blacksmith, had finished his formal education
0:03:52 > 0:03:55when he was just 12 years old.
0:03:55 > 0:03:57He would never get to university.
0:03:57 > 0:03:59But he wasn't finished with learning,
0:03:59 > 0:04:02as he was fascinated by science.
0:04:04 > 0:04:09Faraday worked long and hard during the day, binding books.
0:04:09 > 0:04:13But in the evenings, he'd read whatever scientific literature
0:04:13 > 0:04:15he could lay his hands on.
0:04:15 > 0:04:18He loved learning new things about the world
0:04:18 > 0:04:21and he had this constant desire, this passion,
0:04:21 > 0:04:25to understand why things were they way they were.
0:04:28 > 0:04:32Reading scientific papers was one thing.
0:04:32 > 0:04:36But to really satisfy his craving for knowledge,
0:04:36 > 0:04:39Faraday was desperate to see the experiments themselves.
0:04:39 > 0:04:42And he eventually got his chance
0:04:42 > 0:04:46when he was given a ticket to attend one of the last lectures
0:04:46 > 0:04:50of England's greatest chemist of the time, Sir Humphry Davy.
0:04:53 > 0:04:57It was to change young Faraday's life forever.
0:05:00 > 0:05:04After watching Davy, awe inspired and full of ideas,
0:05:04 > 0:05:07Faraday knew what he wanted to do with his life.
0:05:07 > 0:05:12He was determined to dedicate himself to furthering science.
0:05:12 > 0:05:15And that's just what he did.
0:05:15 > 0:05:19Within a year, Davy had appointed him
0:05:19 > 0:05:21as an assistant at the Royal institution.
0:05:23 > 0:05:27With Davy as his patron and, well, his boss,
0:05:27 > 0:05:31Faraday studied all manner of chemistry.
0:05:31 > 0:05:36But what would inspire his greatest breakthroughs...
0:05:36 > 0:05:40were the invisible forces of electricity and magnetism.
0:05:43 > 0:05:48In 1820, both were being studied by a Danish scientist,
0:05:48 > 0:05:50Hans Christian Oersted,
0:05:50 > 0:05:53who'd made an extraordinary discovery.
0:05:55 > 0:05:59He passed an electric current through a copper rod
0:05:59 > 0:06:03and brought it close to a magnetic compass needle
0:06:03 > 0:06:07and saw that it made the needle rotate.
0:06:07 > 0:06:09To Oersted, it was remarkable.
0:06:09 > 0:06:12He'd shown, for the first time,
0:06:12 > 0:06:16an electric current can create a magnetic force.
0:06:16 > 0:06:20He'd bound electricity and magnetism together.
0:06:20 > 0:06:23Today we call it electro-magnetism.
0:06:23 > 0:06:27And it's one of the fundamental forces of nature.
0:06:29 > 0:06:31Oersted's discovery sparks off a whole new
0:06:31 > 0:06:34aspect of inventive activity
0:06:34 > 0:06:40around and about the fields of electricity.
0:06:40 > 0:06:43You can almost see electrical experimenters vying,
0:06:43 > 0:06:44competing with each other,
0:06:44 > 0:06:48to find new links between electricity and the other powers of nature.
0:06:48 > 0:06:51At the Royal institution,
0:06:51 > 0:06:55Faraday set about recreating Oersted's work,
0:06:55 > 0:06:59which would mark his first steps to fame and fortune.
0:06:59 > 0:07:02And through his rigorous research,
0:07:02 > 0:07:06he concluded that there must be a flow of forces
0:07:06 > 0:07:09acting between the wire and the compass needle.
0:07:09 > 0:07:12The device he designed to demonstrate it
0:07:12 > 0:07:15would change the course of history.
0:07:15 > 0:07:21Faraday created a circuit using a battery like this,
0:07:21 > 0:07:25a pair of wires and a mercury bath.
0:07:25 > 0:07:28Now, the circuit carries on through these copper posts,
0:07:28 > 0:07:32and this wire hangs freely, it dangles into the mercury.
0:07:32 > 0:07:35Now, because mercury is such a good conductor,
0:07:35 > 0:07:38it completes the circuit.
0:07:38 > 0:07:42When the current runs through the circuit...
0:07:43 > 0:07:48..it generates a circular magnetic force-field around the wire.
0:07:48 > 0:07:52Now, this interacts with the magnetism from a permanent magnet
0:07:52 > 0:07:55that Faraday had placed in the middle of the mercury.
0:07:55 > 0:07:59Together they forced the wire to move.
0:07:59 > 0:08:03Faraday had proved that this invisible force really does exist
0:08:03 > 0:08:08and he could see its effect - circular motion.
0:08:08 > 0:08:14This beautiful device was the first to convert electric current
0:08:14 > 0:08:16into continuous motion.
0:08:16 > 0:08:20Basically, it's the earliest ever electric motor.
0:08:25 > 0:08:29But Faraday was about to take this experiment further.
0:08:33 > 0:08:34One of the lasting effects
0:08:34 > 0:08:38of Faraday's discovery of electromagnetic rotations in 1821,
0:08:38 > 0:08:41was that it showed that there was a relationship of some sort
0:08:41 > 0:08:44between electricity and magnetism and motion.
0:08:47 > 0:08:51Faraday explored this relationship in detail
0:08:51 > 0:08:54and set himself an even more difficult challenge.
0:08:55 > 0:09:00To use magnetism and motion to make electricity.
0:09:03 > 0:09:05Eventually, his obsession,
0:09:05 > 0:09:07hard work and determination paid off.
0:09:11 > 0:09:13The breakthrough came
0:09:13 > 0:09:16on the 17th of October 1831,
0:09:16 > 0:09:20when Faraday took a magnet like this and moved it
0:09:20 > 0:09:24in and out of a coil of wire.
0:09:24 > 0:09:29He was able to detect a tiny electric current in the coil,
0:09:29 > 0:09:33moving one way...
0:09:33 > 0:09:36..and then the other.
0:09:37 > 0:09:41Faraday knew he was onto something.
0:09:41 > 0:09:42A few days later,
0:09:42 > 0:09:46instead of moving the magnet through the conducting wire coil,
0:09:46 > 0:09:48he set up the equivalent experiment
0:09:48 > 0:09:53by moving a conducting copper plate through the magnetic field.
0:09:57 > 0:09:59He didn't know it at the time,
0:09:59 > 0:10:03but as his spinning disk cut through this magnetic field,
0:10:03 > 0:10:06billions of negatively charged electrons
0:10:06 > 0:10:09were deflected from their original circular course,
0:10:09 > 0:10:12and began to drift towards the edge.
0:10:14 > 0:10:18A negative charge built up at the outer edge of the disk,
0:10:18 > 0:10:20leaving a positive charge at the centre,
0:10:20 > 0:10:23and once the disk was connected to wires,
0:10:23 > 0:10:27the electrons flowed in a steady stream.
0:10:27 > 0:10:32Faraday had generated a continuous flow of electric current.
0:10:34 > 0:10:35Unlike a battery,
0:10:35 > 0:10:40his current flowed for as long as his copper disk was spun.
0:10:40 > 0:10:45He'd created electrical power directly from mechanical power.
0:10:45 > 0:10:50Although Faraday's discovery of conduction was extraordinarily important in its own right,
0:10:50 > 0:10:54and had profound effects for the understanding of electricity
0:10:54 > 0:10:57and technology for the rest of the 19th century,
0:10:57 > 0:11:03for Faraday what it did is open up a decade of powerful research,
0:11:03 > 0:11:07because it gave him a clue about how he should pursue his research.
0:11:08 > 0:11:12While Faraday continued his work,
0:11:12 > 0:11:15trying to understand the very nature of electricity,
0:11:15 > 0:11:18inventors across Europe were less interested in the science
0:11:18 > 0:11:24and more interested in how electricity could make them money.
0:11:24 > 0:11:28What's actually quite remarkable, certainly from a contemporary perspective,
0:11:28 > 0:11:30is that, by and large,
0:11:30 > 0:11:35nobody really seems to care very much what electricity is.
0:11:35 > 0:11:37You don't have great theoretical debates
0:11:37 > 0:11:41as to whether it's a force, or a fluid, or a principal, or a power.
0:11:41 > 0:11:45What they're really interested in is what electricity can do.
0:11:47 > 0:11:51Faraday, living in a world of steam power,
0:11:51 > 0:11:54was informing the scientific community
0:11:54 > 0:11:56about the nature of electricity,
0:11:56 > 0:11:59but at the same time another breakthrough
0:11:59 > 0:12:03in how we could actually use it had been made.
0:12:03 > 0:12:05This would be the first device
0:12:05 > 0:12:08that really brought electricity out of the laboratory
0:12:08 > 0:12:12and into the hands of ordinary people.
0:12:12 > 0:12:14The telegraph.
0:12:17 > 0:12:20The key to understanding the telegraph
0:12:20 > 0:12:26is understanding a special kind of magnet, an electromagnet.
0:12:26 > 0:12:29Basically, a magnet created by an electric current.
0:12:32 > 0:12:36The first electromagnets were developed independently
0:12:36 > 0:12:40by William Sturgeon in Britain and Joseph Henry in America.
0:12:40 > 0:12:45And just as Faraday had discovered that by coiling his wire,
0:12:45 > 0:12:49he could increase the current in it produced by the moving magnet,
0:12:49 > 0:12:51so Henry and Sturgeon discovered
0:12:51 > 0:12:55that by adding more coils in their current carrying wires,
0:12:55 > 0:12:59they could make a more concentrated magnetic field.
0:12:59 > 0:13:04Basically, the more coils, the more turns, the stronger the magnet.
0:13:04 > 0:13:08So if I pass a current through this electromagnet,
0:13:08 > 0:13:12you can actually see the effects of the magnetic field.
0:13:12 > 0:13:15This is the standard school experiment
0:13:15 > 0:13:18of sprinkling iron filings on top of the magnet.
0:13:18 > 0:13:20If I give it a tap,
0:13:20 > 0:13:25see the iron filings follow the contours of the field.
0:13:25 > 0:13:28This allows us to visualise the effects of magnetism.
0:13:30 > 0:13:33To make an electromagnet even stronger,
0:13:33 > 0:13:37Henry and Sturgeon discovered that they could place
0:13:37 > 0:13:42certain kinds of metal inside the electromagnetic coil.
0:13:42 > 0:13:44The reason iron is so effective is fascinating
0:13:44 > 0:13:48because you can think of it as being made up of lots of tiny magnets,
0:13:48 > 0:13:51all pointing in random directions.
0:13:51 > 0:13:53At the moment, this is not a magnet.
0:13:53 > 0:13:58The tiny magnets inside are aligned similarly to these compass needles.
0:13:58 > 0:14:01If you see, they're all pointing in different directions.
0:14:01 > 0:14:08But when you apply a magnetic field, they all align together,
0:14:08 > 0:14:09they all combine, these magnets,
0:14:09 > 0:14:14and cumulatively they add to the strength of the electromagnet.
0:14:14 > 0:14:17So what Henry and Sturgeon did,
0:14:17 > 0:14:23was place two electromagnetic coils on each arm of their horseshoe,
0:14:23 > 0:14:27to create something that was many, many times more powerful.
0:14:31 > 0:14:36And we can see the power of this horseshoe electromagnet.
0:14:36 > 0:14:41If I turn it on and use something slightly bigger than iron filings,
0:14:41 > 0:14:44these small pieces of iron,
0:14:44 > 0:14:48look at the strength of the magnetic field, holding them in place.
0:14:50 > 0:14:52What's important to remember, of course,
0:14:52 > 0:14:55is that this electromagnet only works
0:14:55 > 0:14:58all the time there's a current passing through it.
0:14:58 > 0:15:01As soon as I turn off the current...
0:15:01 > 0:15:03the magnetism disappears.
0:15:06 > 0:15:11Early experimenters showed off this power by lifting metal weights.
0:15:11 > 0:15:16Henry even made one big enough to lift a tonne-and-a-half of metal.
0:15:16 > 0:15:19Impressive but not world-changing.
0:15:19 > 0:15:23But place that magnet much further away, at the end of a wire,
0:15:23 > 0:15:27and suddenly you can make something happen at your command.
0:15:27 > 0:15:29In an instant.
0:15:33 > 0:15:38This ability to control a magnet at a distance,
0:15:38 > 0:15:41is one of the most useful things we've ever discovered.
0:15:44 > 0:15:46If electricity can be made visible
0:15:46 > 0:15:49a long way away from the original source of power,
0:15:49 > 0:15:52then you've got a source of instantaneous communication.
0:15:57 > 0:15:59By the middle of the 1840s,
0:15:59 > 0:16:02Samuel Morse had developed a messaging system,
0:16:02 > 0:16:08based on how long an electrical circuit was switched on or off.
0:16:08 > 0:16:13A long pulse of current for a dash, a short burst for a dot.
0:16:13 > 0:16:18This allowed messages to be sent and received by using a simple code.
0:16:19 > 0:16:22Contemporary early Victorian commentators
0:16:22 > 0:16:25reflect on the fact that electricity
0:16:25 > 0:16:29and the telegraph is literally making their world a smaller place.
0:16:29 > 0:16:33You very often get a sort of rhetoric throughout the 19th century,
0:16:33 > 0:16:36when people are talking about the telegraph,
0:16:36 > 0:16:40about how more communication, more understanding,
0:16:40 > 0:16:43will render war obsolete,
0:16:43 > 0:16:46because we'll all understand each other better.
0:16:46 > 0:16:50I mean, retrospectively, it seems...hopelessly utopian.
0:16:54 > 0:16:55By the 1850s,
0:16:55 > 0:16:59Europe and America were criss-crossed
0:16:59 > 0:17:01with land-based telegraph wires,
0:17:01 > 0:17:04but the dream of instant global communication
0:17:04 > 0:17:06was frustratingly out of reach.
0:17:06 > 0:17:09This was because there was still no cable
0:17:09 > 0:17:11capable of carrying messages
0:17:11 > 0:17:16between two of the greatest powers on earth -
0:17:16 > 0:17:19Britain and America.
0:17:19 > 0:17:21Many experts were convinced
0:17:21 > 0:17:24that a working Atlantic cable was impossible.
0:17:24 > 0:17:28But those who disagreed knew that if they could solve this problem,
0:17:28 > 0:17:30it could make them serious money.
0:17:30 > 0:17:34And in the 1850s, American businessmen and British engineers
0:17:34 > 0:17:38joined forces to prove this could be done.
0:17:41 > 0:17:44Attempt after attempt ended in disaster.
0:17:44 > 0:17:49The heavy cables kept snapping in heavy seas and storms.
0:17:51 > 0:17:55Finally, on 29th July 1858,
0:17:55 > 0:18:00two parts of a cable were spliced together in mid-Atlantic.
0:18:00 > 0:18:04You see, a single cable was simply too big to be carried by one ship.
0:18:04 > 0:18:07Then one end was taken to Newfoundland,
0:18:07 > 0:18:10and the other end to south-west Ireland.
0:18:10 > 0:18:13Six days later, the first direct link
0:18:13 > 0:18:18between the two most powerful nations in the world was in place.
0:18:18 > 0:18:22The project was hailed a huge success
0:18:22 > 0:18:25and a formal message of congratulations
0:18:25 > 0:18:29was sent from Queen Victoria to President Buchanan.
0:18:29 > 0:18:33But before the celebrations were over,
0:18:33 > 0:18:36things started to go very wrong.
0:18:36 > 0:18:40This is Chief Engineer Bright's original notebook.
0:18:40 > 0:18:45You can see here Queen Victoria's original message.
0:18:45 > 0:18:50Now, it's only 98 words long, but it took 16 hours to transmit.
0:18:51 > 0:18:55The telegraph operators on the other side found it very hard
0:18:55 > 0:18:57to decipher the message.
0:18:57 > 0:18:59The electrical signals they were receiving
0:18:59 > 0:19:01were blurred and distorted
0:19:01 > 0:19:05and they kept asking for words to be repeated over and over again.
0:19:05 > 0:19:06So you can see here,
0:19:06 > 0:19:11"Repeat after sending. Waiting to receive, no signals."
0:19:11 > 0:19:14Clearly, transmitting across the Atlantic
0:19:14 > 0:19:18wasn't going to be as straightforward as people had hoped.
0:19:20 > 0:19:25Over the next few days, several hundred messages were exchanged,
0:19:25 > 0:19:28but those arriving in Newfoundland
0:19:28 > 0:19:31became almost impossible to decipher,
0:19:31 > 0:19:34just a jumbled mess of dots and dashes.
0:19:34 > 0:19:38There was a serious problem with the cable and it was getting worse.
0:19:38 > 0:19:43Well, the 1858 cable was never fully repaired,
0:19:43 > 0:19:49and the end finally came when British engineer Wildman Whitehouse
0:19:49 > 0:19:54mistakenly believed that by increasing the signal voltage
0:19:54 > 0:19:56he could force the messages through to Newfoundland.
0:19:56 > 0:19:59The cable simply stopped working altogether.
0:20:05 > 0:20:07At the time, increasing the voltage
0:20:07 > 0:20:11by using more powerful batteries made sense.
0:20:11 > 0:20:15Most experts believed electric current
0:20:15 > 0:20:18flowed through a cable, like a fluid in a pipe.
0:20:18 > 0:20:21Increasing the voltage was the equivalent
0:20:21 > 0:20:24of increasing the pressure in the system -
0:20:24 > 0:20:28forcing the current through to the other end.
0:20:28 > 0:20:31But the telegraph was actually carrying pulses,
0:20:31 > 0:20:33or ripples of currents along the cable,
0:20:33 > 0:20:36not a continuous stream.
0:20:36 > 0:20:38And over long distances,
0:20:38 > 0:20:41these pulses were becoming distorted,
0:20:41 > 0:20:45making it difficult to tell what was a short dot
0:20:45 > 0:20:48and which was a longer dash.
0:20:48 > 0:20:52By studying the effectiveness of underwater cabling,
0:20:52 > 0:20:54scientists were beginning to understand
0:20:54 > 0:20:59that electric current didn't always flow like water,
0:20:59 > 0:21:05but was also creating invisible electromagnetic waves, or ripples.
0:21:05 > 0:21:09And it's this breakthrough that would lead to a new branch
0:21:09 > 0:21:12of research into the electromagnetic spectrum,
0:21:12 > 0:21:17and solve the problems of the Atlantic telegraph.
0:21:18 > 0:21:20In effect, the Transatlantic Cable
0:21:20 > 0:21:26was a giant, ambitious, hugely expensive experiment.
0:21:26 > 0:21:32The failure of science to keep pace with technology had been exposed.
0:21:32 > 0:21:38And a new, more theoretical and, for me, much more exciting approach
0:21:38 > 0:21:43to understanding electricity began to unfold.
0:21:47 > 0:21:51Armed with this new understanding of how electric pulses
0:21:51 > 0:21:55actually moved along the cable, improvements were made
0:21:55 > 0:21:59to its composition, design, and how it was laid.
0:22:02 > 0:22:06It would take another eight years of scientists and engineers
0:22:06 > 0:22:11working together before a working cable was finally put in place.
0:22:13 > 0:22:17And on Friday 27th July 1866,
0:22:17 > 0:22:21a message was sent from Ireland to Newfoundland.
0:22:21 > 0:22:23Clear and crisp.
0:22:25 > 0:22:30"A treaty of peace has been signed between Austria and Prussia."
0:22:31 > 0:22:35At last, the dream of instant transatlantic communication
0:22:35 > 0:22:36had become a reality.
0:22:39 > 0:22:45The success of the 1866 cable makes the world a smaller place.
0:22:45 > 0:22:47Yet again.
0:22:49 > 0:22:54The change from a world where it took days or weeks or months
0:22:54 > 0:22:56for information to travel,
0:22:56 > 0:23:02to a world in which information took seconds or minutes to travel -
0:23:02 > 0:23:03it is far more profound
0:23:03 > 0:23:07than almost anything that's taken place during my lifetime.
0:23:09 > 0:23:14The invention of the telegraph changed ordinary people's lives.
0:23:14 > 0:23:16But it would be the breakthroughs
0:23:16 > 0:23:20in how we used continuously flowing electric current
0:23:20 > 0:23:23that would have an even greater impact.
0:23:25 > 0:23:30Because inventors were developing a new way of using electricity.
0:23:34 > 0:23:39To make something every person in the world would want -
0:23:39 > 0:23:42electric light.
0:23:45 > 0:23:48Until the 19th century,
0:23:48 > 0:23:54we only knew of one way to make our own light - burn things.
0:24:02 > 0:24:05And by the middle of the 19th century,
0:24:05 > 0:24:09we'd perfected a very effective way of lighting our homes -
0:24:09 > 0:24:10using gas.
0:24:15 > 0:24:19A typical British home in the 1860s would have been lit like this -
0:24:19 > 0:24:20highly-flammable gas
0:24:20 > 0:24:24would have been pumped directly into people's houses
0:24:24 > 0:24:26through a network of pipes.
0:24:29 > 0:24:34But these gas lamps were too dull for large outdoor areas.
0:24:34 > 0:24:38So railway stations and streets began to be lit
0:24:38 > 0:24:42from a more powerful source - electric arc lights.
0:24:44 > 0:24:47The first arc lights were demonstrated
0:24:47 > 0:24:51by Michael Faraday's mentor, Sir Humphry Davy,
0:24:51 > 0:24:53at the Royal institution as early as 1808,
0:24:53 > 0:24:58and they worked by passing a continuous spark of electricity
0:24:58 > 0:25:01across two carbon rods.
0:25:04 > 0:25:09But their intense white glow was just too bright for people's homes.
0:25:09 > 0:25:12For an electric light to compete with gas,
0:25:12 > 0:25:15it would need to be subdivided into many smaller,
0:25:15 > 0:25:19less powerful and more gentle lamps.
0:25:19 > 0:25:22Whoever succeeded in bringing electric light
0:25:22 > 0:25:26to every home in the land was guaranteed fame and fortune.
0:25:26 > 0:25:31And by the early 1880s, the most famous, most prodigious,
0:25:31 > 0:25:34most fiercely competitive inventor in the world
0:25:34 > 0:25:36had taken on the challenge.
0:25:36 > 0:25:41The American, Thomas Alva Edison.
0:25:42 > 0:25:45For Edison, invention was a passion,
0:25:45 > 0:25:49it's what he loved doing. He loved being in the laboratory.
0:25:49 > 0:25:52The first thing that drove that passion is that
0:25:52 > 0:25:56it was a lot of fun for Edison. That was the thing that he found
0:25:56 > 0:26:00most exciting, is that this was something he did well,
0:26:00 > 0:26:05and it allowed all of his creativity to come to the fore.
0:26:05 > 0:26:07Edison is Mr Electrical Invention.
0:26:09 > 0:26:11He's the man they trust.
0:26:11 > 0:26:16He's the man that they think can do anything.
0:26:16 > 0:26:21He's also the man who has his carefully cultivated connections
0:26:21 > 0:26:26with entrepreneurs, with people that are willing to put their cash
0:26:26 > 0:26:28where Edison's mouth is, so to speak,
0:26:28 > 0:26:31and back him in this sort of venture.
0:26:31 > 0:26:34For Edison, the money was probably the least important reason.
0:26:34 > 0:26:37For Edison, the money was important for one reason -
0:26:37 > 0:26:39to allow him to do the next project.
0:26:41 > 0:26:47Edison had assembled a group of young and talented engineers
0:26:47 > 0:26:50at a cutting-edge laboratory in New Jersey,
0:26:50 > 0:26:5226 miles from Manhattan.
0:26:54 > 0:26:56Menlo Park would become
0:26:56 > 0:27:00the world's first research and development facility,
0:27:00 > 0:27:04allowing Edison's team to invent on an industrial scale.
0:27:06 > 0:27:09They worked incredible hours, you know,
0:27:09 > 0:27:12one of them talked about how he hardly ever saw his children
0:27:12 > 0:27:14cos he was in the lab all the time.
0:27:20 > 0:27:24But they knew they were in the midst of something really important.
0:27:24 > 0:27:25That if Edison succeeded,
0:27:25 > 0:27:28if they succeeded with Edison, their futures were secure.
0:27:35 > 0:27:40Edison's dream was to bring electric light to every home in the land,
0:27:40 > 0:27:42and with his team of engineers behind him,
0:27:42 > 0:27:47and the vision of an electric future ahead, he launched his campaign.
0:27:49 > 0:27:53The race to bring electric light to the world was to play out
0:27:53 > 0:27:58in the great cities of the time - New York, Paris, London.
0:27:59 > 0:28:03Edison's Menlo Park team set about developing
0:28:03 > 0:28:07a totally different form of electric lamp -
0:28:07 > 0:28:09the incandescent light bulb.
0:28:10 > 0:28:16In fact, Edison's light bulb design wasn't all that new. Or unique.
0:28:16 > 0:28:20French, Russian, Belgian and British inventors
0:28:20 > 0:28:24had been perfecting similar bulbs for over 40 years.
0:28:24 > 0:28:28And one of them, an Englishman, Joseph Swan,
0:28:28 > 0:28:33had been developing his own version of an incandescent lamp.
0:28:33 > 0:28:35Both Swan and Edison's light bulbs
0:28:35 > 0:28:38worked by passing an electric current through a filament.
0:28:38 > 0:28:43Now, a filament is a material in which the electric current
0:28:43 > 0:28:46flows through with more difficulty than it does
0:28:46 > 0:28:51through the copper wire in the rest of the circuit.
0:28:51 > 0:28:53And it relies on the idea of resistance.
0:28:53 > 0:28:57Inside this jar, I have a filament made out of ordinary pencil lead,
0:28:57 > 0:29:01and we can see what happens as I pass a current through it.
0:29:03 > 0:29:05Down at the atomic scale,
0:29:05 > 0:29:08the atoms in the filament impede the flow of electricity.
0:29:08 > 0:29:12So it takes more energy to force it through,
0:29:12 > 0:29:15and this energy is deposited in the filament as heat.
0:29:15 > 0:29:18Now, as it heats up, its resistance goes up,
0:29:18 > 0:29:23which again raises its temperature, until it glows white-hot.
0:29:26 > 0:29:28Now, one of the first materials
0:29:28 > 0:29:31Edison used for his filaments was platinum.
0:29:35 > 0:29:38With its relatively high melting point,
0:29:38 > 0:29:40platinum could be heated
0:29:40 > 0:29:43to a white-hot temperature without melting.
0:29:43 > 0:29:48It could also be stretched into thin strands, and the thinner the strand,
0:29:48 > 0:29:53the more resistance it offered to the current passing through it.
0:29:53 > 0:29:57But platinum was expensive and didn't offer enough resistance.
0:29:59 > 0:30:03The race was on to find a better alternative
0:30:03 > 0:30:07and the solution came when the Menlo Park team
0:30:07 > 0:30:11switched to a method Swan was also developing,
0:30:11 > 0:30:14using a vacuum to stop cheaper carbon filaments
0:30:14 > 0:30:16from burning up too quickly.
0:30:18 > 0:30:21Edison and Swan tested all kinds of different materials
0:30:21 > 0:30:23for their filaments -
0:30:23 > 0:30:27everything from raw silk and parchment to cork.
0:30:27 > 0:30:31Edison even tested his engineers' beard hair.
0:30:31 > 0:30:34Eventually, he settled on bamboo fibre,
0:30:34 > 0:30:37while Swan used a treated cotton thread.
0:30:38 > 0:30:43Edison and Swan's light bulb designs were very similar.
0:30:43 > 0:30:46Eventually they came to an agreement and went into partnership
0:30:46 > 0:30:49to sell light bulbs in the UK.
0:30:49 > 0:30:53Today, many people still believe that Edison alone
0:30:53 > 0:30:58invented the light bulb, whilst Swan has become a footnote in history.
0:31:05 > 0:31:10But his incandescent bulb was only part of Edison's strategy.
0:31:10 > 0:31:16He'd also invented an entire electrical system of sockets,
0:31:16 > 0:31:17cables, and meters to go with it.
0:31:17 > 0:31:20And, being a brilliant businessman,
0:31:20 > 0:31:26he'd developed a ground-breaking new way of distributing electricity.
0:31:26 > 0:31:30Edison knew that the key to making money from his system
0:31:30 > 0:31:33was to generate the electricity in a central station,
0:31:33 > 0:31:37and then sell it to as many customers as possible.
0:31:37 > 0:31:39It seems obvious to us now, but until then,
0:31:39 > 0:31:41anyone who wanted to use electricity
0:31:41 > 0:31:45had to have their own noisy generator to make it.
0:31:47 > 0:31:50Edison's ambition was huge -
0:31:50 > 0:31:53he wanted to light the fastest-growing
0:31:53 > 0:31:56and most exciting city in the world.
0:32:00 > 0:32:01New York.
0:32:03 > 0:32:07In the summer of 1882, Edison stood in a unique position,
0:32:07 > 0:32:11at the centre of 19th century science and invention.
0:32:11 > 0:32:16He'd patented a cutting-edge incandescent light bulb,
0:32:16 > 0:32:20he'd amassed an unprecedented knowledge of electrical engineering.
0:32:20 > 0:32:21And above all,
0:32:21 > 0:32:24he'd cultivated a reputation among the American public
0:32:24 > 0:32:27of being such a genius inventor,
0:32:27 > 0:32:29that journalists hung on his every word,
0:32:29 > 0:32:32and the financial muscle of Wall Street
0:32:32 > 0:32:36was quick to throw itself behind his new ideas.
0:32:36 > 0:32:38His vision, to electrify Manhattan,
0:32:38 > 0:32:41and then, of course, the rest of the world,
0:32:41 > 0:32:44was seemingly within his grasp.
0:32:49 > 0:32:50Because Edison and his team
0:32:50 > 0:32:56were about to launch their most expensive and risky project yet -
0:32:56 > 0:32:58America's first power station,
0:32:58 > 0:33:01generating continuous direct current.
0:33:06 > 0:33:10Just before 3pm on the 4th September 1882, Thomas Edison,
0:33:10 > 0:33:14surrounded by a gaggle of bankers, dignitaries and reporters,
0:33:14 > 0:33:17entered JP Morgan's building, right behind me,
0:33:17 > 0:33:20flicked one of the Edison-patented switches,
0:33:20 > 0:33:26and 100 of his incandescent bulbs began to glow.
0:33:26 > 0:33:28Turning to a nearby journalist, he said,
0:33:28 > 0:33:32"I have accomplished all that I've promised."
0:33:35 > 0:33:39Half a mile away on Pearl Street, Edison's new power station,
0:33:39 > 0:33:44costing half a million dollars and four years of hard work,
0:33:44 > 0:33:45had sprung into life.
0:33:47 > 0:33:49The current surged through buried cables,
0:33:49 > 0:33:53stretching out in each direction.
0:33:53 > 0:33:56Of course it might seem obvious to us now,
0:33:56 > 0:33:59but in New York back in the early 1880s,
0:33:59 > 0:34:02the idea of burying electric cables underground
0:34:02 > 0:34:05seemed like an unnecessary expense.
0:34:05 > 0:34:08This street would have been criss-crossed
0:34:08 > 0:34:11with hundreds of cables, used for telegraphs,
0:34:11 > 0:34:13telephones and arc street lighting.
0:34:13 > 0:34:18Looking up, you'd have seen a tangled mass of black spaghetti
0:34:18 > 0:34:20blocking out the light.
0:34:20 > 0:34:24Edison knew this dangerous situation had to change,
0:34:24 > 0:34:29and for him to make as much money as he could,
0:34:29 > 0:34:33electricity needed rebranding. It had to be considered safe.
0:34:33 > 0:34:37So Edison is arguing both for the greater safety
0:34:37 > 0:34:42of his DC low voltage system, and for underground lines.
0:34:42 > 0:34:45He can argue that he has a much safer system
0:34:45 > 0:34:49than electric arc light for streets,
0:34:49 > 0:34:52or gas lighting for indoor lighting.
0:34:52 > 0:34:56He doesn't have to worry about fires, or electrocution,
0:34:56 > 0:34:57that all of this is much safer
0:34:57 > 0:35:00because of the system he's created with this underground system.
0:35:03 > 0:35:06Burying every cable was not only very expensive
0:35:06 > 0:35:09but was a logistical nightmare,
0:35:09 > 0:35:13because this was one of the busiest square miles in the world.
0:35:13 > 0:35:16Edison chose this area for a reason.
0:35:16 > 0:35:18Wall Street.
0:35:18 > 0:35:21Rich, important, influential.
0:35:21 > 0:35:24Because for Edison's system to make money,
0:35:24 > 0:35:26all these wealthy customers
0:35:26 > 0:35:29had to be within a mile of his power station.
0:35:32 > 0:35:35And this was because Edison calculated
0:35:35 > 0:35:37the thickest cable he could afford
0:35:37 > 0:35:42would only carry an adequate amount of his continuous direct current
0:35:42 > 0:35:46to customers within this range.
0:35:46 > 0:35:49This was a huge leap forward
0:35:49 > 0:35:51because, for the first time,
0:35:51 > 0:35:56dozens of customers could be supplied by just one power station.
0:35:56 > 0:35:58But there was a big problem.
0:35:58 > 0:36:01Edison's network could never be economical in lighting
0:36:01 > 0:36:04America's new suburbs.
0:36:04 > 0:36:07They just didn't have the concentration of customers
0:36:07 > 0:36:11needed to make building these expensive power stations worthwhile.
0:36:12 > 0:36:14Had we stuck with Edison's way
0:36:14 > 0:36:17of generating and distributing electricity,
0:36:17 > 0:36:20the world would be a very different place.
0:36:21 > 0:36:25We'd have to have power stations scattered around
0:36:25 > 0:36:30no more than a mile apart, even in the centres of our towns and cities.
0:36:30 > 0:36:34And it would be extraordinarily expensive to even provide power
0:36:34 > 0:36:36for smaller communities.
0:36:39 > 0:36:43But someone who held the answers to these problems
0:36:43 > 0:36:45was about to enter the story.
0:36:45 > 0:36:49Someone who would help create the modern world
0:36:49 > 0:36:53and who'd play an integral part in one of the biggest fall-outs
0:36:53 > 0:36:55in scientific history.
0:36:55 > 0:36:57His name was Nikola Tesla
0:36:57 > 0:37:00and he was right under Edison's nose.
0:37:06 > 0:37:10Nikola Tesla was a Serbian inventor
0:37:10 > 0:37:12who was born in Croatia
0:37:12 > 0:37:14and who worked for Edison briefly
0:37:14 > 0:37:18after arriving in New York at the age of 28.
0:37:18 > 0:37:22European, introverted, a deep thinker,
0:37:22 > 0:37:26he was everything Edison wasn't.
0:37:26 > 0:37:28Edison and Tesla could not be more different
0:37:28 > 0:37:32in the way they handled their self, appearance, and their manners,
0:37:32 > 0:37:35and the way that they constructed a public image for themselves.
0:37:35 > 0:37:38Edison couldn't care less about the clothes he had on
0:37:38 > 0:37:41and if he spilt chemicals on his good Sunday suit,
0:37:41 > 0:37:43then he spilt chemicals on his good Sunday suit.
0:37:43 > 0:37:48He was, you know, basically, a very kind of slovenly guy.
0:37:48 > 0:37:50Tesla, on the other hand,
0:37:50 > 0:37:54even as a young man in his mid 20s, is thinking about his appearance,
0:37:54 > 0:37:56how he comes across to people.
0:37:56 > 0:37:58So he cares about his clothes, his manner.
0:37:58 > 0:38:02Indeed, he even cares about how his photograph,
0:38:02 > 0:38:03his portraits are taken,
0:38:03 > 0:38:07and he always wants to make sure he has a nice, three-quarter profile
0:38:07 > 0:38:10so you don't see the fact that he has a bit of a pointy chin.
0:38:12 > 0:38:15The life and death of Nikola Tesla
0:38:15 > 0:38:19is one of the most fascinating yet tragic stories
0:38:19 > 0:38:23of scientific brilliance, cut-throat business,
0:38:23 > 0:38:26and shocking public relations stunts.
0:38:29 > 0:38:32The American public may have been wowed
0:38:32 > 0:38:35by Edison's new direct current power stations,
0:38:35 > 0:38:37but Tesla was less impressed.
0:38:37 > 0:38:43He had a dream electricity could be transmitted across entire cities.
0:38:43 > 0:38:45Or even nations.
0:38:45 > 0:38:48And he believed he knew how it could be done -
0:38:48 > 0:38:53by using a different type of electric current.
0:38:57 > 0:39:01Electrical experts knew that the smaller the current
0:39:01 > 0:39:06sent down a cable, the smaller the losses in it through resistance.
0:39:06 > 0:39:09And so the longer the cable could be.
0:39:09 > 0:39:14Tesla proposed using a method of transmitting electricity
0:39:14 > 0:39:17where the currents could be lowered without a fall
0:39:17 > 0:39:20in the amount of electrical power at the other end.
0:39:20 > 0:39:22It was called alternating current.
0:39:24 > 0:39:27Alternating current is exactly that.
0:39:27 > 0:39:30It's an electric current that alternates
0:39:30 > 0:39:32between moving in one direction,
0:39:32 > 0:39:35then the opposite direction, very quickly.
0:39:35 > 0:39:40As opposed to a direct current, which moves only in one direction.
0:39:40 > 0:39:43Tesla was interested in alternating current because,
0:39:43 > 0:39:47like other electrical engineers in the late 1880s,
0:39:47 > 0:39:51he realised that as you raise the voltage of any current
0:39:51 > 0:39:54that you transmit from point A to point B,
0:39:54 > 0:39:58it's going to be more efficient to have a higher voltage.
0:39:59 > 0:40:03And since the amount of electric power in a cable is its voltage
0:40:03 > 0:40:07multiplied by its current, increasing the voltage,
0:40:07 > 0:40:10meant the current in the cables could be reduced,
0:40:10 > 0:40:14and so losses due to resistance would be less.
0:40:14 > 0:40:17However, you don't want very high voltages
0:40:17 > 0:40:21on the order of, say, 20,000 volts coming into your home.
0:40:21 > 0:40:22So you need to step down the current
0:40:22 > 0:40:25that is being transmitted over distance into your home.
0:40:25 > 0:40:29And to do that, you need a converter or transformer.
0:40:29 > 0:40:34Alternating current allows you to use a transformer
0:40:34 > 0:40:37to make that switch from the high transmission voltage
0:40:37 > 0:40:40to the lower voltage you're going to use at consumption.
0:40:42 > 0:40:46Perfecting the technology to transmit electricity
0:40:46 > 0:40:50hundreds of miles from where it was generated
0:40:50 > 0:40:53would mark a huge step towards the modern world.
0:40:54 > 0:40:57And a wealthy industrial entrepreneur
0:40:57 > 0:41:00was already developing the solution.
0:41:00 > 0:41:03His name was George Westinghouse.
0:41:03 > 0:41:06Westinghouse believed alternating currents was the future,
0:41:06 > 0:41:10but it had a big drawback.
0:41:10 > 0:41:12While it was fine for electric light,
0:41:12 > 0:41:14unlike direct current,
0:41:14 > 0:41:18there was no practical motor that could run on it.
0:41:18 > 0:41:21And no-one believed there ever would be.
0:41:21 > 0:41:23Apart from Nikola Tesla.
0:41:24 > 0:41:26Tesla, as an inventor, liked to say
0:41:26 > 0:41:31that the first thing you need to do is not to build something,
0:41:31 > 0:41:34but to imagine it, to think it through, to plan it.
0:41:34 > 0:41:38And he had what modern-day psychologists would call
0:41:38 > 0:41:40an eidetic memory. He could basically
0:41:40 > 0:41:42remember everything that he saw
0:41:42 > 0:41:45and then visualise it in three dimensions.
0:41:45 > 0:41:48And they often say people that have this skill
0:41:48 > 0:41:50see it about an arm's length away,
0:41:50 > 0:41:53out here, and they see it in three dimensions in that space.
0:41:53 > 0:41:56And all the indications are that Tesla had that ability.
0:42:00 > 0:42:04This is a Tesla egg.
0:42:06 > 0:42:08It's a replica of the one Tesla used
0:42:08 > 0:42:11to demonstrate his greatest breakthrough
0:42:11 > 0:42:16and one of the most important inventions of all time.
0:42:16 > 0:42:18It showed how rotary movement
0:42:18 > 0:42:22can be produced directly from an alternating current.
0:42:22 > 0:42:26Crucially, one that could be generated thousands of miles away.
0:42:26 > 0:42:30This was something that had never been done before.
0:42:38 > 0:42:41When Tesla was working on the alternating current motor,
0:42:41 > 0:42:43he was thinking big.
0:42:43 > 0:42:46He was not just tinkering with one component
0:42:46 > 0:42:49of the motor and saying, "Gee, if I can make that a little bit better,
0:42:49 > 0:42:52"it will work out." He's actually thinking about
0:42:52 > 0:42:56an entire system that involves the generator,
0:42:56 > 0:42:58the wires to the motor
0:42:58 > 0:43:00and the motor itself. He's a complete maverick,
0:43:00 > 0:43:03thinking outside the box,
0:43:03 > 0:43:06doing things very differently to his fellow inventors.
0:43:06 > 0:43:09Tesla's solution was ingenious.
0:43:09 > 0:43:13He fed more than one alternating current into his motor
0:43:13 > 0:43:17and timed them so that they followed in sequence with each other.
0:43:17 > 0:43:20The first alternating current
0:43:20 > 0:43:24energised a coil of wire inside the motor,
0:43:24 > 0:43:26creating an electromagnetic field
0:43:26 > 0:43:30which attracted the motor's central moving part to it
0:43:30 > 0:43:32and then faded.
0:43:32 > 0:43:36The second overlapping current fed the next coil,
0:43:36 > 0:43:40dragging the moving part around further, before it faded.
0:43:40 > 0:43:43And the same for the third coil and the fourth.
0:43:43 > 0:43:47The result was a revolving magnetic field,
0:43:47 > 0:43:50strong enough to make the motor,
0:43:50 > 0:43:52or in this case his egg, spin.
0:43:52 > 0:43:56Tesla designed an entire electrical system around this
0:43:56 > 0:43:59called polyphase transmission.
0:43:59 > 0:44:02This meant a noisy and smelly power station,
0:44:02 > 0:44:05generating lots of useful alternating current,
0:44:05 > 0:44:09could now be situated away from populated areas.
0:44:10 > 0:44:13And for the first time you can build large power stations
0:44:13 > 0:44:15wherever you want. On the edge of town,
0:44:15 > 0:44:17or a waterfall like Niagara,
0:44:17 > 0:44:20and distribute the power over long distances,
0:44:20 > 0:44:22and serve all the people
0:44:22 > 0:44:25in a major city or metropolitan centre.
0:44:25 > 0:44:30Tesla's breakthrough was the last piece of the jigsaw,
0:44:30 > 0:44:33but he still had to convince the world
0:44:33 > 0:44:35that his solution was better
0:44:35 > 0:44:39than the direct current method championed by Edison.
0:44:43 > 0:44:48Edison continued to roll out his direct current system,
0:44:48 > 0:44:51building power stations across New York state.
0:44:55 > 0:44:59But then Tesla met George Westinghouse -
0:44:59 > 0:45:03the man who could make his dreams into a reality.
0:45:05 > 0:45:10In July 1888, Westinghouse made an offer for Tesla's patents,
0:45:10 > 0:45:13which has become part of the mystery and folklore
0:45:13 > 0:45:16surrounding the whole Nikola Tesla story,
0:45:16 > 0:45:20where it's difficult to separate fact from fiction.
0:45:21 > 0:45:26Tesla was paid 75,000 for his alternating current patents
0:45:26 > 0:45:29and offered 2.50
0:45:29 > 0:45:32for every horse power his motors would generate.
0:45:32 > 0:45:35This should have guaranteed him vast wealth
0:45:35 > 0:45:39for the rest of his life but that isn't what happened.
0:45:42 > 0:45:44It's clear to us now that at the time,
0:45:44 > 0:45:47the AC system was a much better method
0:45:47 > 0:45:49of transmitting electric power.
0:45:49 > 0:45:52And you'd think that with Tesla's breakthroughs,
0:45:52 > 0:45:57nothing could stand in the way of the success of AC over DC.
0:45:57 > 0:46:00But one man still believed totally
0:46:00 > 0:46:02in his direct current inventions,
0:46:02 > 0:46:06From the filaments of the bulbs to the switches,
0:46:06 > 0:46:07sockets and generators,
0:46:07 > 0:46:11and he wasn't about to waste millions of dollars
0:46:11 > 0:46:13on changing them.
0:46:13 > 0:46:16Edison.
0:46:17 > 0:46:19The battle lines were drawn.
0:46:19 > 0:46:23Westinghouse and Tesla went toe-to-toe with Edison
0:46:23 > 0:46:26for New York's lucrative lighting contracts.
0:46:26 > 0:46:29Two completely different systems
0:46:29 > 0:46:32battling it out for one ultimate prize -
0:46:32 > 0:46:37the chance to light up America and then the world.
0:46:37 > 0:46:41It would become known as the War of the Currents.
0:46:45 > 0:46:48Both camps tried to undercut each other on cost,
0:46:48 > 0:46:52but Edison believed his beloved direct current
0:46:52 > 0:46:56was better than alternating current because it was safer.
0:46:58 > 0:47:02Touching an Edison cable, with its low voltage,
0:47:02 > 0:47:04was painful but relatively harmless.
0:47:04 > 0:47:06Whereas alternating current cables
0:47:06 > 0:47:10carried a much higher voltage
0:47:10 > 0:47:13and touching them could be deadly.
0:47:13 > 0:47:16So, what Edison was trying to do
0:47:16 > 0:47:22was to again define his DC system as the safe system.
0:47:22 > 0:47:26It's better than electric street arc lights,
0:47:26 > 0:47:28it's better than gas,
0:47:28 > 0:47:31and it's now better than high voltage AC incandescent lighting.
0:47:31 > 0:47:34Right? It's the system that's safe.
0:47:34 > 0:47:38You adopt the Edison system, you can be sure it's safe.
0:47:41 > 0:47:42Edison claimed that AC
0:47:42 > 0:47:46was a more dangerous type of current than DC
0:47:46 > 0:47:50and he highlighted every accident to Westinghouse's workmen
0:47:50 > 0:47:53and every fire caused by short circuits.
0:47:58 > 0:48:01It was a potent message because in the 1880s,
0:48:01 > 0:48:05many people were still terrified by electricity.
0:48:05 > 0:48:09It could shock and even kill in an instant
0:48:09 > 0:48:13and the reasons why still weren't fully understood.
0:48:13 > 0:48:18For many, the idea of piping this invisible killer into their homes
0:48:18 > 0:48:19was utterly ludicrous.
0:48:22 > 0:48:27So the weapon used in the War of the Currents was fear.
0:48:31 > 0:48:34And a little-known electrical engineer,
0:48:34 > 0:48:36Harold P. Brown,
0:48:36 > 0:48:39was about to take the fight against AC
0:48:39 > 0:48:41to a whole new level.
0:48:44 > 0:48:48It was to prove one of the most extreme
0:48:48 > 0:48:51and negative publicity campaigns in history.
0:48:51 > 0:48:56Brown had devised a unique and theatrical way
0:48:56 > 0:48:59of demonstrating the deadly power of AC...
0:49:00 > 0:49:03..and he was eager to share it with the world.
0:49:03 > 0:49:09So, on a warm summer's evening, in July 1888,
0:49:09 > 0:49:12he gathered together 75 of the country's
0:49:12 > 0:49:15top electrical engineers and reporters
0:49:15 > 0:49:19to witness a spectacle they would never forget.
0:49:24 > 0:49:28Brown's plan was extremely macabre.
0:49:28 > 0:49:30He'd paid a team of street urchins
0:49:30 > 0:49:33to collect together stray dogs roaming Manhattan.
0:49:33 > 0:49:36Out on stage, he addressed his audience.
0:49:36 > 0:49:39"I have asked you here, gentlemen,
0:49:39 > 0:49:44"to witness the experimental application of electricity
0:49:44 > 0:49:47"to a number of brutes."
0:49:48 > 0:49:52His demonstration involved electrocuting the dogs...
0:49:52 > 0:49:54with DC and AC power,
0:49:54 > 0:50:01in an attempt to show that AC current killed them more quickly.
0:50:01 > 0:50:04And it wasn't just dogs.
0:50:04 > 0:50:08Brown went on to make public spectacles of killing a calf
0:50:08 > 0:50:09and even a horse.
0:50:11 > 0:50:14And he moved from dogs to larger animals for a reason.
0:50:14 > 0:50:19He wanted to show that the AC form of electricity was so dangerous
0:50:19 > 0:50:23it could kill any large mammal, including humans.
0:50:32 > 0:50:38Brown's animal experiments had persuaded American politicians
0:50:38 > 0:50:42the most humane method of executing condemned criminals
0:50:42 > 0:50:44should be with alternating current,
0:50:44 > 0:50:46generated by Westinghouse machines.
0:50:48 > 0:50:52Edison's lawyers even suggested a new term
0:50:52 > 0:50:56to describe being electrocuted in this way...
0:50:56 > 0:50:58..to be Westinghoused.
0:50:59 > 0:51:02And at precisely 6:32,
0:51:02 > 0:51:07on the morning of 6th August 1890,
0:51:07 > 0:51:10a 45-year-old man, William Kemmler,
0:51:10 > 0:51:12was strapped to a wooden chair
0:51:12 > 0:51:14and two soaking wet electrodes
0:51:14 > 0:51:17were carefully attached to him.
0:51:17 > 0:51:21And as 26 officials and doctors looked on from an adjoining room,
0:51:21 > 0:51:25Kemmler said goodbye to the prison chaplain and waited.
0:51:30 > 0:51:32The execution of William Kemmler
0:51:32 > 0:51:36marked the lowest point in the War of the Currents,
0:51:36 > 0:51:39but it wouldn't quite mark the end.
0:51:39 > 0:51:42Because Nikola Tesla was about to do something
0:51:42 > 0:51:44that had never been seen before.
0:51:44 > 0:51:46Something so wondrous and daring
0:51:46 > 0:51:50that it would live on for ever in the memories of those who saw it.
0:52:14 > 0:52:17Tesla had been developing a method
0:52:17 > 0:52:20of generating very high frequency alternating currents
0:52:20 > 0:52:22and on May 21st 1891,
0:52:22 > 0:52:25at a meeting of top electrical engineers,
0:52:25 > 0:52:27he demonstrated it.
0:52:33 > 0:52:38In an almost magical display of awesome power and wonder,
0:52:38 > 0:52:41and without wearing any safety chain mail or mask,
0:52:41 > 0:52:46tens of thousands of volts, produced by a Tesla coil,
0:52:46 > 0:52:51passed across his body and through the end of a lamp he was holding.
0:52:56 > 0:53:01Tesla's alternating current was at such a high frequency,
0:53:01 > 0:53:03that it passed through his body
0:53:03 > 0:53:06without causing serious harm or even pain.
0:53:07 > 0:53:10His demonstrations showed that if handled correctly,
0:53:10 > 0:53:15alternating current at extremely high voltages could be safe.
0:53:16 > 0:53:20The War of the Currents had been won,
0:53:20 > 0:53:22by Westinghouse and Tesla.
0:53:22 > 0:53:28In 1896, the new power station was completed at Niagara Falls,
0:53:28 > 0:53:30using Westinghouse AC generators
0:53:30 > 0:53:33to produce Tesla's polyphase current.
0:53:33 > 0:53:36Finally, huge amounts of power
0:53:36 > 0:53:40could be transmitted from the Falls,
0:53:40 > 0:53:42to nearby Buffalo and then, a few years later,
0:53:42 > 0:53:48the Niagara plant was providing power to New York City itself.
0:53:48 > 0:53:53And today, almost all of the electricity generated in the world
0:53:53 > 0:53:56is done so using Tesla's system.
0:54:03 > 0:54:07But Tesla's story doesn't end in fame and fortune.
0:54:10 > 0:54:13Although he went on to make significant contributions
0:54:13 > 0:54:16to many other areas of science and invention,
0:54:16 > 0:54:21to save George Westinghouse from ruin, after a stock market crash,
0:54:21 > 0:54:23he gave up his claim to the royalties
0:54:23 > 0:54:26from his polyphase inventions.
0:54:29 > 0:54:34Nikola Tesla was a uniquely talented man and we owe him so much.
0:54:34 > 0:54:36But he was also hugely complicated,
0:54:36 > 0:54:40and sadly, later in life, he became more and more troubled.
0:54:40 > 0:54:42He was fixated with the number three,
0:54:42 > 0:54:45counting it out loud while he walked,
0:54:45 > 0:54:49and he developed strange phobias with germs
0:54:49 > 0:54:52and with women wearing pearl jewellery.
0:54:53 > 0:54:58In many ways, his brilliant mind simply spun out of control.
0:55:01 > 0:55:03As Tesla's life unravelled,
0:55:03 > 0:55:05he withdrew from people
0:55:05 > 0:55:08and found emotional comfort elsewhere.
0:55:08 > 0:55:10He became obsessed with pigeons
0:55:10 > 0:55:14and was regularly seen feeding them here in Bryant Park,
0:55:14 > 0:55:16in the centre of Manhattan.
0:55:16 > 0:55:20He even fell in love with one particularly unusual white bird
0:55:20 > 0:55:22and when it died,
0:55:22 > 0:55:24he was left heart broken.
0:55:35 > 0:55:40As an old man, Tesla was left almost bankrupt and alone,
0:55:40 > 0:55:44living as a semi-recluse in this hotel.
0:55:51 > 0:55:58His last years were spent here in room 3327 of the New York Hotel,
0:55:58 > 0:56:00sad, confused, destitute.
0:56:06 > 0:56:11Edison went on to become an American hero
0:56:11 > 0:56:15and his company would form part of General Electric,
0:56:15 > 0:56:20even today one of the world's biggest multinational corporations.
0:56:21 > 0:56:28In January 1943, the story of Nikola Tesla was coming to an end.
0:56:30 > 0:56:34But looking out across the Manhattan skyline for the very last time,
0:56:34 > 0:56:38he saw a sky lit up with twinkling lights,
0:56:38 > 0:56:42and a million lives transformed by his genius.
0:56:59 > 0:57:02The ability to generate and transmit electricity,
0:57:02 > 0:57:05and the invention of machines to use it,
0:57:05 > 0:57:10have changed our world in ways we couldn't possibly have imagined.
0:57:11 > 0:57:15We can now generate billions of watts of electricity
0:57:15 > 0:57:18every second, every hour, every day.
0:57:19 > 0:57:23And whether we do it using coal, gas,
0:57:23 > 0:57:25or nuclear fission,
0:57:25 > 0:57:27power stations all rely
0:57:27 > 0:57:32on the principles discovered and developed by Michael Faraday,
0:57:32 > 0:57:34Nikola Tesla,
0:57:34 > 0:57:37and all the other early electrical engineers
0:57:37 > 0:57:39from an amazing age of invention.
0:57:39 > 0:57:43We now take electricity for granted
0:57:43 > 0:57:49and have forgotten how magical and mysterious a force it once was.
0:57:49 > 0:57:51But there's something we should never forget.
0:57:51 > 0:57:56Today, without it, the modern world would collapse around us
0:57:56 > 0:58:00and our lives would be very, very different.
0:58:06 > 0:58:10In the next episode, we tell of the electrical revelations
0:58:10 > 0:58:14that led to a revolution in our understanding
0:58:14 > 0:58:16of this amazing force.
0:58:19 > 0:58:23To find out more about the story of electricity,
0:58:23 > 0:58:25and to put your power knowledge to the test,
0:58:25 > 0:58:29try the Open University's interactive energy game.
0:58:29 > 0:58:31Go to:
0:58:34 > 0:58:37And follow links to the Open University.
0:58:59 > 0:59:02Subtitles by Red Bee Media Ltd 2011
0:59:02 > 0:59:05E-mail subtitling@bbc.co.uk