Can you see me?Can you hear me?How?I could be thousands of miles away,and yet, when you turn on whatever device is bringing my image and voice to you,I’m there.Instantaneously.
How is that possible?
To our ancestors,it would’ve seemed like sorcery.For them, speed of communication was only as fast as the swiftest horse or sailing ships.Our messages travel invisibly at the speed of light.How did we attain such mythic powers?It all began in the mind of one person.A child of poverty of whom nothing was expected.
In fact,if this man had not lived…the world we know might not exist today.Sooner or later,someone would’ve likely figured out some of his discoveries.But if Michael Faraday had never lived,we might still be living as our ancestors did in the 17th century.Unaware of armies of invisible servants awaiting our commands.
This is the story of how we learned to make electrons do our bidding.In a way, it begins with the greatest genius who ever lived–Isaac Newton.
This is Woolsthorpe, Newton’s ancestral home.He walked these fields, tormented by mystery.Newton, the man who figured out the formula for the motions of the planets around the Sun,wanted to know how does the Sun make the planets act that way
without touching them?How do all the apples know how to fall?
Another genius was puzzled by another aspectof the same mystery.
“You see, son?No matter how I turn the compass,the needle always points the same way.Except…””But how?They do not touch.””I didn’t hear a “Thank you,” Albert.”
“I can still remember this.The experience made a deep and lasting impression on me.Something deeply hidden had to be behind things.”
Between the lifetimes of Einstein and Newton,there lived another genius,one of equal stature.The man who solved the mystery that stumped Newton,also laid the foundation for Einstein’s revolutionary insights.And for the way we live now.
In 1791, in a squalid slum in the suburbs of London,Michael Faraday was born.
He showed little promise at school.
“Pray tell us a word that begins with the letter R.Well?”
“Wabbit?”
“The word is “Rabbit.”Once again,and correctly this time.”
“Wabbit?”
“Do you mock me?Have I not told you how to pronounce the letter R?Surely you can at least tell us your name?”
“Michael “Fawaday,” ma’am.”
“Take this ha’penny,and buy me a cane,so that I may give your insolent brother a proper flogging.”
History does not record that Michael Faraday ever attended school again.Faraday took his family’s fundamentalist Christian faith to heart.It would always remain a source of strength,comfort and humility for him.He was sent to work at a bookbindery at the age of 13.By day, he bound the books,and by night,he read them.It was the beginning of a lifelong fascination with electricity.After years of working in the bookbindery,Faraday, now 21,yearned to escapeto a larger world.His big break came when a customergave him a ticket to a sensationalnew kind of entertainment–science for the public.
And it started right here at London’s Royal Institution.
Humphry Davy was not only one of the leading scientists of his day,he discovered several chemical elements,including calcium and sodium.He was also a consummate showman.And primitive demonstrations of electricity never failed as a crowd pleaser.
“May we have the lights lowered, please?I am about to unleash the might of the 2,000 massive chemical batteries stored in the cellar beneath our feet.And now, behold the power of the mysterious force of electrical fluid to illuminate our future.”
Faraday was too busy taking notes to applaud.
Faraday created a transcript of Davy’s lecture.Using the skills he had learned as an apprentice,he bound them into this book.Perhaps such a gift would bring him to the attention of the great man.Maybe this gesture could be a means of escape to a much larger universe.
“Good day, sir.I wish you to deliver this parcel to Sir Humphry.”It was a long shot, anyway.But Faraday hoped something would come of it.And it did.
“Uh, the experiment is ready for you now, sir.”
“Ampere tells me that poor Dulong lost an eyeand three fingers working with this.”
“My eyes!My eyes!”
When a chemical experiment blew up in the face of the world-renowned scientistHumphry Davy,he remembered Michael Faraday,the lad who had gone through such lengths to copy down and bind the transcript of his lecture.
“You have a first-rate memory, young man.And I shall have temporary need of a secretary.”
“Sir, I dream of a life in service to science.”
“I would advise you to stick to the bookbinding.Science is a harsh mistress.Surely, a person of your station and modest means must have a trade.”
“Trade is vicious and selfish.Men of science are amiable and morally superior.”
“I take it I’m the first man of scienceyou’ve ever met.”
Faraday made himself indispensable to Davy.The temporary job became a permanent one,and the Royal Institution became his lifelong home.By day, he assisted Davy in the lab,at day’s end, he climbed the stairs to the little apartment where his beloved bride Sarah was waiting.
Humphry Davy and the chemist William Wollaston were experimenting with a mysterious phenomenon,one with potentially far-reaching implications.
“This is the identical setup to Orsted’s.Now close the circuit, Davy, and watch closely.”
“What could be driving the needle away from the wire?”
“Damned if I know.
“But it’s as if the electric current makes the wire behave like some kind of magnet.Electricity must have something to do with magnetism.”
“Now if we could only get it to turn continuously,imagine what might be accomplished if we could putthese forces to work.”
“After you tidy up, Faraday,you might see whatyou can make of it.”
Davy may have been having a bit of fun at the expenseof his young assistant,but Faraday was on fire.Up to now, electricity had been nothing more than an entertaining novelty toy.It could make a light flash for an instant or turn a compass needle briefly,but it had no practical application.
Faraday immediately set about designing the experiment,devoting every moment of his spare time to the problem.If Faraday succeeded,he would be putting an infinitely large, invisible,and as-yet-undiscovered army of electrons at the command of human whim.
How does a revolution begin?Sometimes it doesn’t take much.A piece of metal,a bowl of mercury,a bit of cork.
“Sarah dear,send your little brother down.I’m about to try something knew,and I want him to see it.
Why don’t you dothe honors, Georgie.”
“There she goes.There she goes!”
This was the first motorconverting electric current into continuous mechanical motion.
Looks pretty feeble, right?But that turning spindleis the beginning of a revolution,one that dwarfs all the shots fired
and bombs ever detonated in the sheer magnitude of its effect on our civilization.Try to imagine all the businesses,
industries, technologies,transformations of the way we live
that have their beginnings in that ecstatic moment in Michael Faraday’s laboratory.
News of Faraday’s invention spread quickly,and suddenly, Davy’s assistant was the toast of London.
Davy didn’t take it well.He had, after all, discovered all those elements.Now people were saying that his greatest discovery was Michael Faraday.Davy made sure that Faraday wouldn’t be making any more headlines anytime soon.
“You sent for me, sir?”
“I have a new challenge for you.I want you to take over our efforts to improve the quality of British optical glass.Those damned Bavariansare running circles around us.”
“Glass?With all due respect, sir,I know nothing at allof glass-making.”
“Then you will learn, Faraday.We all know whata quick study you are.Just analyze the chemical composition of their glass and work backwards to see how they made it.It shouldn’t take you long.”
But Faraday struggled for four yearswithout any success.This is even worsethan the last batch.No matter how hard he tried,Faraday could not figure out what Joseph Fraunhofer had discovered years before.What Faraday failed to grasp was that casting perfect optical glass for telescopes was a craft as well as a science,and the masters in Bavaria kept their secrets under lock and key.Faraday never did learn their secret.He kept a single glass brick as a souvenir of this failure.Years later, it would change the course of his life…and ours.
Davy’s death finally brought an end to this fruitless project,
and Faraday,the boy from the slums,succeeded him as Director of the Laboratory.Faraday used his new authority to do something unprecedented–a series of annual Christmas lectures on science for the young… beginning in 1825 and continuing to this day.
At one of the first Christmas lectures,Faraday enchanted his audience with displays of the new powers that were at his disposal.
“Suppose I want to fire a portion of gunpowder.I can readily do it with the power of electricity.If I receive electricity through this conducting wire,I can then give it to anything I touch.But I must stand on these insulating glass legto prevent the electricity from going away into the floor.
Now I am electrified!”
“Whoa!”
“Do you think I could light this gas jetjust by touching it with my finger?”
“No, don’t do it! No!”
“No! Don’t!”
“Now, mind you, don’t try this at home.”
“And now, my children,you have seen for yourselves how this invisible force of electricity can be made to serve new purposes utterly unattainable by the powers we have now.”
The invention of a motorthat could work continuously,eliminating countless human hours of drudgery,would be more than enough to make you a fortune and land you in the history books.But that’s not how Michael Faraday saw it.He had absolutely no interest in patenting his ideas or personally profiting from them.And as for the history books,he had only written the first sentence of an entry that would be many pages long.
“Mr. Anderson, may I ask youto dim the lights, please?
Gentlemen, I am about to induce a current of electricity
merely by moving a magnet.Please observe what happens
in the gap between the wires when I do so.
Do you see how the current only flows when the magnet is moving?This is the conversionof motion into electricity.”
This was the first generator.From here, electricity would become available on demand.Faraday was continuing to change the world and the way people lived,and then, suddenly,an illness attacked his incomparable mind.
“My dear Schoenbein,I would be very grateful to have your opinion regarding…Regarding…
Dear Schoenbein…Regarding…”
“My dear husband,whatever is the matter?”
“I began a letter to Schoenbeinand could not remember what I meant to say.”
“This is no cause for alarm.You work too hard.- You’re exhausted.”
“No.Sarah, this is different.Horribly different.It’s the third time my memory has failed me in as many days.I fear I’m losing my mind.And what would I be without that?”
“Why, my darling husband, of course.”
When Faraday was 49,he began to battle severe memory loss and depression.His work came to a standstill.And although he never fully recovered,his greatest achievements still lay ahead.Faraday had immersed himself so deeply in electricaland magnetic experiments that he came to visualize the space around a magnet as filled with invisible lines of force.A magnet was not simply the magnetized bar of iron that you could see.It was also the unseen something in the space around the bar.And that something he called a field.
A magnetic field.
Faraday believed in the unity of nature.Having demonstrated the connections between electricity and magnetism, he wondered,were these two forces also connected to a third– light?If he could only show a connection among these three invisible phenomena,one of nature’s most intimate secrets would at last be revealed.
So, what did he do?
He designed an experiment.
Faraday knew that light can travel as a wave.Waves of light vibrate randomly in all directions.But there’s a way to isolate a single wave of light.It’s called polarization.
When light bounces off a reflective surface,like a mirror,it becomes polarized.
Faraday wanted to see if that single ray of light could be manipulated by the invisible magnetic field.
The eyepiece contained a crystalthat acted as a kind of picket fence for light.Light could only pass through it if it was somehow moved by the magnet.
He placed a lantern before a mirror,one that he would only see through the eyepiece if its reflection could pass through the picket fence.If this is hard to understand,don’t feel bad.Scientists could not explain this phenomenon for another 100 years.
Faraday knew that magnetism had no effect on light that was moving through air.But what about when it was moving through other materials?So what kind of material could he use to help the magnet move the light?
He tried hundreds of different transparent chemicals and objects…but saw nothing through the eyepiece.The light was not twisted by the magnet.He tried crystals of calcite,sodium carbonate,calcium sulfate,and still, he saw nothing.He tried acids.Sulfuric acid,muriatic acid,carbonic acid.He tried gasses…oxygen, nitrogen, hydrogen…with no success.The magnetic field induced in these substances could not twist the lightfrom his lamp back into view.
In desperation,he decided to try…the glass brick,the souvenir of his years of bondage to Davy.
It did the trick.The force of the magnet twisted the light so that it could pass through the crystal.
So, what’s the big deal?Faraday had demonstrated the existence of the physical reality that surrounds us,but which no one had ever been able to detect.It was as dramatic a breakthrough as seeing the cosmos for the very first time through a telescope.By showing that an electromagnetic force could manipulate light,Faraday had discovered a deeper unity of nature.He had opened a door for Einstein and all the physicists who came after him to glimpse the interplay of hidden, primal forces in the universe.
Even as he approached the summit of his genius,
he was plagued by depression and doubts about his ability
to retain eventhe simplest thoughts.
“My dear friend, I find a difficulty in answering or even acknowledging properly a scientific letter,for I cannot now hold it at once in my mind.The memory of the parts fail me.”
“P.S. You will be sorry to see the tone of this short note,but my dearest husband is not quite so well as usual,but I hope he will improve.Yours very truly, S. Faraday.”
As a young man,Faraday had risen from poverty,in one of the mostclass-conscious societies the world has ever known,to become the most celebrated scientist of his time.
By age 40, he had invented the electric motor,the transformer, the generator,machines that would change everything about the home,the farm, the factory.
Now, at 60, decades afterthe fertile periods of the greatest physicists,plagued by memory loss and melancholy,he fearlessly probed deeper into the mysterious invisible forces.The world thought that Michael Faraday was a has-been.
Despite his depression,he remained as passionately curious as ever.Having discovered the unity of electricity,magnetism and light,Faraday needed to know how this trinity of natural forces work together.
“♪ this is the way the ladies walk… ♪”
This was nothing new.Children had been playing with magnets and iron filings for centuries.Everyone had always assumed that this lovely pattern was just somethingthat iron did.Faraday knew that electric current turns a wire into a magnet,so he expectedto find related patterns in iron filings around a wire carrying electricity.But where others saw merely lovely shapes,Faraday saw something profound.The patterns were not simply a quirk of iron filings;they existed in the space around a magnet or an electric current,even in the absence of iron filings.The patterns were the traces,the footprints of invisible fields of force,that reached out into the space around anything magnetic.
The compass needle that people wondered at for a thousand years was not reacting to some far away magnetic North Pole.It was detecting a continuous force field that stretched all the way there.Earth itself is a giant magnet.And like any other magnet,its lines of force extend far out into the space surrounding it.They’re everywhere, all around us.They’ve always been.But nobody had ever noticed them before.Nobody human, that is.
Birds are the last living descendants of the dinosaurs.Pigeons and other birds are remarkably good at finding their way around.They can migrate thousands of miles without getting lost.How? Partly by recognizing familiar landmarks–rivers, mountains, stars.Even certain smells can serve as signposts for migrating birds.But birds also have an inner compass.They can actually sense the Earth’s magnetic field.Their brains process magnetic data in much the same way ours process visual data.By sensing the direction of the field,birds can tell north from south.That’s one way North American birds know which way to go when they head south for the winter.The field is stronger near the poles than it is at the equator,a fact that birds use to figure out their latitude.There are also smallirregularities in the field,locations where the field is a little weaker or stronger.Just like a distinctive mountain or river,these magnetic anomalies can serve as landmarks.For thousands of years, humans have used carrier pigeons to send messages to distant locations.It was a crucial method of communication as recently as World War II.When you think about it, we’ve been using magnetic fields to communicate for a long time.We just didn’t know it.
So why does our planet have a magnetic field at all?What causes it?
The answer lies deep inside the Earth.
Liquid iron, circulating around the solid part of the core as Earth rotates,acts like a wirecarrying an electric current.And as Faraday showed us,electric currents produce magnetic fields.And that’s a good thing.Our magnetic field protects us from the onslaughtof cosmic rays, which would be very damaging to our biosphere.Cosmic rays can rip through DNA.Without our magnetic field,the rate of mutation in living organisms would be much higher.Fortunately, most of this cosmic shrapnel gets trapped in the Van Allen belts,donut-shaped zones of charged particles corralled by our magnetic shield.
Knowing that the Earth itself is like a giant bar magnet explains one of the most beautiful sights in the sky,Charged particles from the Sun, the solar wind,are constantly bombarding the Earth.You can think of the solar wind as a kind of electric current.Our planet’s magnetic field channels that current towards the North and South Poles.When it hits our atmosphere,the oxygen and nitrogen molecules in the air glow like giant fluorescent lightbulbs.
When Faraday pursued his last and most profound discovery,the poverty of his childhood stymied him as it never had before.He needed help and found it in one who had come from another world.Michael Faraday had solved the mystery that baffled Isaac Newton.This was how the Sun told the planets how to move without touching them.The Sun does touch the planets with its gravitational field,and Earth’s gravitational field tells the apples how to fall.
All this is a dream.
Unfortunately, that was the prevailing view among his fellow scientists.Faraday was dreaming.They admired his inventiveness and his genius for experimentation,but they regarded his invisible “lines of force” and his ideas about light and gravity as hand-waving,meaning there was nothing solid to back it up.Some openly ridiculed his theories.They needed to see his ideas expressed in the language of modern physics,precise equations.
This was the one area where Faraday’s childhood poverty and lack of formal education actually held him back.He couldn’t do the math.Faraday had finally hit a wall that he could not overcome.
And then, the greatest theoretical physicist of the 19th century came along.James Clerk Maxwell was born into a world of wealth and privilege,an only child of doting middle-aged parents.By his early 20s, he had made a name for himself as a mathematician.While other scientists had cometo think of Faraday as old-fashioned;a great figure of the pastbut no part of the future of physics,James Clerk Maxwellknew better.He began by reading everything Faraday had written on electricity.He became convinced that Faraday’s fields of force were real, and he set out to give them a precise mathematical formulation.
An equation in physics is just a shorthand description of something that can be represented in space and time.For instance, the equation that describes the arc of a pendulum shows that it can never swing higher than its initial height.
When Maxwell translated Faraday’s experimental observation on electromagnetic fields into equations,he discovered an asymmetry.See that bottom one?It cries out for something else.
Great mathematician that he was,Maxwell added a single term to balance it.This tweaking of the equation changed Faraday’s static field into waves that spread outward at the speed of light.
It wasn’t long before we found a way to turn those waves…into couriersfor our messages.
Can you see me?Can you hear me?This is how.
This technology has transformed human civilization from a patchwork of cities,towns and villages into an intercommunicating organism…linking us at light speed…to each other…and to the cosmos.
Nothing is too wonderful to be true,if it be consistent with the laws of nature.
