BBC Shock and Awe : The Story of Electricity

On the 14th August 1894,

an excited crowd gathered outside Oxford's Natural History Museum.

This huge Gothic building was hosting the annual meeting

of the British Association for the Advancement of Science.

Over 2,000 tickets had been sold in advance

and the museum was already packed,

waiting for the next talk to be given by Professor Oliver Lodge.

His name might not be familiar to us now,

but his discoveries should have made him as famous

as some of the other great electrical pioneers of history.

People like Benjamin Franklin,

Alessandro Volta,

or even the great Michael Faraday.

Quite unwittingly, he would set in motion a series of events

that would revolutionise the Victorian world

of brass and telegraph wire.

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

a world dominated by silicone and mass wireless communication.

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

through broadcasting and computer networks,

and how we finally learnt to unravel and exploit electricity

at an atomic level.

After centuries of man's experiments with electricity,

a new age of real understanding was now dawning.

These tubes are not plugged in to any power source,

but they still light up.

It's electricity's invisible effect,

an effect not just confined to the wires it flows through.

In the middle of the 19th century,

a great theory was proposed to explain how this could be.

The theory says that surrounding any electric charge -

and there's a lot of electricity flowing above my head -

is a force field.

These florescent tubes are lit purely because they are under

the influence of the force field from the power cables above.

The theory that a flow of electricity could, in some way,

create an invisible force field, was originally proposed

by Michael Faraday, but it would take a brilliant young Scotsman

called James Clark-Maxwell, who would prove Faraday correct -

and not through experimentation, but through mathematics.

This was all a far cry from the typical 19th century way

of understanding how the world works,

which was essentially to see it as a physical machine.

Before Maxwell, scientists had often built strange machines

or devised wondrous experiments to create and measure electricity.

But Maxwell was different.

He was interested in the numbers, and his new theory not only revealed

electricity's invisible force field, but how it could be manipulated.

It would prove to be one of the most important

scientific discoveries of all time.

Maxwell was a mathematician and a great one

and he saw electricity and magnetism in an entirely new way.

He expressed it all in terms of very compact mathematical equations.

And the most important thing is that in Maxwell's equations

is an understanding of electricity and magnetism as something linked

and as something that can occur in waves.

Maxwell's calculations showed how these fields could be disturbed

rather like touching the surface of water with your finger.

Changing the direction of the electric current

would create a ripple or wave

through these electric and magnetic fields.

And constantly changing the direction

of the flow of the current, forwards and backwards,

like an alternating current, would produce a whole series of waves,

waves that would carry energy.

Maxwell's maths was telling him that changing electric currents

would be constantly sending out great waves of energy

into their surroundings.

Waves that would carry on forever unless something absorbed them.

Maxwell's maths was so advanced and complicated

that only a handful of people understood it at the time,

and although his work was still only a theory,

it inspired a young German physicist called Heinrich Hertz.

Hertz decided to dedicate himself to designing an experiment

to prove that Maxwell's waves really existed.

And here it is.

This is Hertz's original apparatus

and its beauty is in its sheer simplicity.

Heat generates and alternating current that runs

along these metal rods, with a spark that jumps across the gap

between these two spheres.

Now, if Maxwell was right,

then this alternating current should generate an invisible

electromagnetic wave that spreads out into the surroundings.

If you place a wire in the path of that wave,

then at the wire, there should be a changing electromagnetic field,

which should induce an electric current in the wire.

So what Hertz did was build this ring of wire, his receiver,

that he could carry around in different positions in the room

to see if he could detect the presence of the wave.

And the way he did that was leave a very tiny gap in the wire,

across which a spark would jump if a current runs through the ring.

Now, because the current is so weak, that spark is very, very faint

and Hertz spent pretty much most of 1887

in a darkened room staring intensely through a lens

to see if he could detect the presence of this faint spark.

But Hertz wasn't alone in trying to create Maxwell's waves.

Back in England, a young physics Professor called Oliver Lodge

had been fascinated by the topic for years

but hadn't had the time to design any experiments

to try to discover them.

Then one day, in early 1888, while setting up an experiment

on lightning protection, he noticed something unusual.

Lodge noticed that when he set up his equipment

and sent an alternating current around the wires,

he could see glowing patches between the wires,

and with a bit of tweaking,

he saw these glowing patches formed a pattern.

The blue glow and electrical sparks occurred in distinct patches

evenly spaced along the wires.

He realised they were the peaks and troughs of a wave,

an invisible electromagnetic wave.

Lodge had proved that Maxwell was right.

Finally, by accident, Lodge had created

Maxwell's electromagnetic waves around the wires.

The big question had been answered.

Filled with excitement at his discovery, Lodge prepared

to announce it to the world, at that summer's annual scientific meeting

run by the British Association.

Before it, though, he decided to go on holiday.

His timing couldn't have been worse, because back in Germany,

and at exactly the same time,

Heinrich Hertz was also testing Maxwell's theories.

Eventually, Hertz found what he was looking for...

a minute spark.

And as he carried his receiver to different positions in the room,

he was able to map out the shape of the waves

being produced by his apparatus.

And he checked each of Maxwell's calculations carefully

and tested them experimentally.

It was a "tour de force" of experimental science.

Back in Britain,

as the crowds gathered for the British Association meeting,

Oliver Lodge returned from holiday relaxed and full of anticipation.

This, Lodge thought, would be his moment of triumph,

when he could announce his discovery of Maxwell's waves.

His great friend, the mathematician Fitzgerald, was due to give the opening address in the meeting.

But in it, he proclaimed that Heinrik Hertz had just published astounding results.

He had detected Maxwell's waves travelling through space.

"We have snatched the thunderbolt from Jove himself

"and enslaved the all prevailing ether", he announced.

Well, I can only imagine how Lodge must have felt

having his thunder stolen.

Professor Oliver Lodge had lost his moment of triumph,

pipped at the post by Heinrich Hertz.

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

though he didn't know it at the time, will lead to a whole revolution in communications over the next century.

Maxwell's theory had shown how electric charges could create

a force field around them.

And that waves could spread through these fields like ripples on a pond.

And Hertz had built a device that could actually create

and detect the waves as they passed through the air.

But, almost immediately,

there would be another revelation in our understanding of electricity.

A revelation that would once again involve Professor Oliver Lodge.

And, once again, his thunder would be stolen.

The story starts in Oxford, in the summer of 1894.

Hertz had died suddenly earlier that year,

and so Lodge prepared a memorial lecture with a demonstration

that would bring the idea of waves to a wider audience.

Lodge had worked on his lecture.

He'd researched better ways of detecting the waves,

and he'd borrowed new apparatus from friends.

He'd made some significant advances in the technology

designed to detect the waves.

This bit of apparatus generates an alternating current

and a spark across this gap.

The alternating current sends out an electromagnetic wave,

just as Maxwell predicted, that is picked up by the receiver.

It sets off a very weak electric current through these two antennae.

Now, this is what Hertz had done.

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

The weak electric current passes through the filings,

forcing them to clump together.

And, when they do, they close a second electric circuit

and set off the bell.

So if I push the button on this end...

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

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

It's like magic.

BELL RINGING/ELECTRICAL BUZZING

If you could imagine a packed house,

lots of people in the audience, and what they suddenly see is,

as if by magic, a bell ringing.

It's quite incredible.

BELL RINGS

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

but it certainly still created a sensation among the crowd.

Lodge's apparatus, laid out like this,

no longer looked like a scientific experiment.

In fact, it looked remarkably like those telegraph machines

that had revolutionised communication, but without those long cables

stretching between the sending and receiving stations.

To the more worldly and savvy members of the audience,

this was clearly more than showing the maestro Maxwell was right.

This was a revolutionary new form of communication.

Lodge published his lecture notes on how electromagnetic waves

could be sent and received using his new improvements.

All around the world, inventors, amateur enthusiasts

and scientists read Lodge's reports with excitement