Nuclear science has provided mankind with immense potential to do good, to treat and perhaps cure some of the most deadly of diseases, to provide virtually free electricity, to investigate the structure of the universe, to examine the most detailed mechanisms of the human body. It has also, of course, provided the world with something else. This is the nightmare of the second half of the twentieth century: a suitcase with an atomic bomb inside it. Once you steal the nuclear material, any physics graduate can do the rest. It’s a timing device with an electrical circuit that fires two explosive charges, which push the radioactive material together fast enough for it to go critical, and boom! And there is no security force on Earth that can prevent some fanatical nutcase from placing this gently in downtown Anywhere. This breakthrough in military technology completely unbalances the situation carefully worked for over the last thirty years by the major nuclear powers. The nightmare is what the result will be.

One of the results of the breakthrough in military technology that happened here, was that I’m speaking to you in English instead of a language close to, say, Dutch. Because this is the site of the Battle of Hastings in 1066. That abbey up there was built to commemorate the event. The battle itself lasted maybe five and a half hours. It was an immensely violent affair full of sweat and fear and blood. Hand-to-hand combat in those days was unbelievably unpleasant because it maimed people rather than killing them. You died of your wounds later. They did most of the good work with this. I’d like you to see what it does to a side of meat. Because in hand-to-hand combat, that’s all a man is.

On a bitterly cold morning on October 14^th, 1066, about 16,000 men began to do that as hard and as desperately as they could to each other in this field here. The Saxon king, Harold, had his headquarters straight up there on the top of the ridge where the abbey is now, and he disposed his men—about 8,000 of them—from over there at the top of that ridge, along the crest of the hill, for about half a mile to the horizon over there as far as you can see. Now, of those 8,000 men, he had about 5,000 professional soldiers—exhausted from a 270-mile march in the previous ten days, backed up by about 3,500 local farmers who’d been given hammers and pitchforks and billhooks to do whatever they could with. They were told, “Come here and do your thing.”

Now, in front of him—in front of Harold—about 150 meters down the hill, arranged also along left to right, were the troops of William the Conqueror. 8,000 men again, but all battle-hardened, well-trained troops. 1,000 archers, 4,000 heavy infantry, and 3,000 cavalry.

Okay. The battle started, went on all morning. Nobody could make any headway going up. The Normans could get nothing against the Saxons, who just stood there and fought into a standstill all the time. Around noon, everybody stopped. They pulled apart. They picked up their weapons. They had something to drink, something to eat. And at about three o’clock they started again. And this time, William sent his cavalry straight up the hill at the Saxon shield wall. It banged up against it and got no further.

And they fought and fought and fought, until finally the Norman cavalry began to pull back, and it was then that the Saxons made their real mistake. The Saxons broke lines and came chasing down here after the Normans. And here, on level ground, where I’m standing, was where England became Norman. Because it was here that the Saxons allowed the Normans the one advantage, that one technological device they had that the Saxons didn’t have. And it was the use of that device that changed the history of the Western world irrevocably.

It’s the way the Normans fought that tells you they were using that device. Look: see the long shield? That’s used to protect the left side of the body, because the rider’s carrying a lance with the other hand, so he can’t fight off an attack. And the only reason you use a lance like that is if you’ve got the device the Normans were using: the stirrup. The Saxons lost because the Normans were fighting from horseback, thanks to the stirrup. Trouble was, you hit so hard, you lost your lance.

As the stirrup went into more general use, the first change it brought about was this: a bit of cloth you could use to help heave your lance back out of the corpse. Sixty years after Hasting, anybody who was anybody was fighting from horseback, wearing more armor to protect themselves, so they were heavier. So while the massive shock of the impact might kill the other guy, it knocked you backwards off your horse. And a fat lot of use you were to anybody in a heap on the ground.

Still, this was such a good way to slaughter people, there had to be some way to make it work. And by the middle of the twelfth century they’d come up with what they thought was the answer. They raised the back of the saddle so the rider couldn’t come off, and strengthened the saddle girth. Unfortunately, that just transferred the shock to the poor old horse. The only answer was a stronger horse that could take all that punishment. And rearing big horses—as anybody who knows will tell you—ain’t cheap.

Now, keeping a man like that supplied with the latest weaponry and horses in a period when there was very little money in circulation needed the kind of wealth that could only come from land and peasants working it. So as you’ll see, the coming of the knight changed the basic structure of society. It also gave birth to the tournament. Now, in all the books they’re shown like that. But in reality they were very different.

Early on, the tournament was a kind of cross between the circus coming to town and a wild free-for-all, where half the time things ended in absolute shambles with whole towns getting burned down. Things got so out of hand, even the Pope tried to ban the fun and games. Yes, these were definitely the days of courtly manners and fair play. But behind all the chicanery and dirty tricks, there were two very good reasons for these affairs, and they both had to do with fighting on horseback. See, the idea of cavalry was a whole new thing. And you needed all the training you could get to use the lance right.

The other reason had to do with the prizes you won. You knocked a guy off his horse at a tournament, and you took everything: his armor, his saddle, his horse, the lot. And that was as good as a free ticket to the upper classes. Because it was only when you possessed all the right equipment and the horses that you got into the big league.

By 1250, the big league was a very exclusive club only the very rich could join.—thanks, in the first place, to the stirrup, and the way it had led to the fully-armored knight on his massive war horse. The aristocrats now made sure the club stayed exclusive. They made knighthood hereditary, and took on permanent family names instead of just being “son of somebody.” And because the armor covered their faces, they needed identification marked to show who they were in battle, so they didn’t get clobbered by their own men. These heraldic symbols completed the separation of the aristocrats from the rest. Immensely powerful and immensely rich, the armor-plated upper crust must have felt that they had absolutely got it made.

By the fourteenth, the knight was a massive, expensive, complex two-ton war machine. And at full gallop he would annihilate anything coming the other way—except, of course, another knight. And then, from out of the valleys of South Wales, came something that was to take away from the armored knight his four centuries of domination like that.

That was the Shakespearean version of this man, Henry V, talking about the day when everybody discovered that it was never going to be the same again for the knight on horseback at the Battle of Agincourt in northern France between Henry and the French on the morning of October 25^th, 1415.

It’s funny, isn’t it, how we all seem to need big-time heroes like Henry. And yet, you read Shakespeare (the heavy stuff), and you come here to Westminster Abbey, and you see the king lying on his tomb and the sword he used in the battle, and you totally lose sight of the fact that, as a young man of 28, well, Henry may have been a dab hand with imagined words, but he would’ve been nowhere in that battle if it hadn’t been for the one thing he had, and his French enemy didn’t—and I don’t mean his princely sex appeal! Let me tell you what happened.

Henry here had… oh… about 8,000 men, knocked out with fatigue from marching nonstop for seventeen days in the rain. About a mile away, across a battlefield of mud, there were 30,000 Frenchmen, half of them fully-armored aristocrats who’d been up the previous night because they’d slept in their saddles because they didn’t want to get their lovely armor dirty. They were an arrogant, overbearing, effete lot, full of “death ’o glory” and “me first!” So when, at about 11 o’clock in the morning, Henry had some arrows shot at this mob in order to get them to do something—anything! Because they’d been standing around arguing the toss about who should be running the French armies since 7 in the morning. And he suddenly upped and charged straight at Henry, straight across a sea of mud, straight onto the stakes that the English had put, point up, in their path. And that was when Henry played his trump card—didn’t you? He called up the secret weapon his grandfather had discovered in the mountains of Wales. And when it came into action, the slaughter was unimaginable.

That weapon was the Welsh longbow, and Henry had over 1,000 of them. In the hands of a master, the longbow would kill at 400 yards. And in three bloody hours the French were massacred.

Many of the French knights had their horses shot from under them to fall in the mud and suffocate as the bodies of their dead companions piled on top of them. When it was all over, the English had lost maybe 500 men, the French 10,000—most of them buried here in a common grave under my feet. The longbow did most of that. It was a terrifying weapon.

And yet, a generation after Agincourt, they couldn’t find enough archers to muster a company, let alone an army. The reason? Well, because that’s the way things go. The reason has nothing to do with Agincourt or war or weapons.

It had to do with food, and it had to do with the fields the food came from and the way the people worked the fields—like these peasants in the Duc de Berry’s Book of Hours. With 90% of the population on the land, any development in agricultural technology would affect everybody. And in the seventh century (700 years before Agincourt), three agricultural inventions came one after the other to fundamentally change people’s lives.

The first was a new kind of plow. See, up until then, the plow in general use had been little more than a digging stick pulled by oxen. It came from the Mediterranean, where it’s still in use today in the Middle East. And it was good enough for the job of turning over the light soil in that area. But up here in Northern Europe, it got you nowhere. Soil is too thick. So when, around 700 AD, this came along, it made a very big impression. It had wheels, it had a knife to cut through the sod, and the plowshare had a curved board attached to it. This new plow would cut through anything. Look!

You see what the knife does? It cuts open the sod and makes it easier for the plowshare that follows. And then the curved board throws the soil up and away to one side, leaving a clean furrow. With a team of, say, eight oxen in front of this, you could farm the thick, rich land up here that no earlier plow could ever have done. It was bloody hard work, but it could be done. So by about 900 AD, this plow was opening up the north really fast, clearing the forests, producing more food. And in consequence the population was rising.

Now, in those days, this would’ve had a team of oxen up front, not a horse. The plow and the oxen were very expensive. Few peasant farmers could afford the whole deal. So they formed cooperatives, each man bringing what he could. And as they began to work close together, they began to live close together in big groups, villages. That’s why villages happened.

So the first invention was the plow. The second came towards the end of the ninth century. The situation was that, up until then, they were using oxen in front of the plow. And if you put an ox harness on a horse, it cuts across under the neck and strangles the animal. The horse collar—that was the second invention—spread the load on the horse’s shoulders, and so now you could use a horse. Now, a horse will do twice as much work as an ox, because it does it faster. So production doubled and the population rose again.

The third invention took them and their horses further afield. Yes, it was the horseshoe. See, with a shoe, you can use a horse in all weathers, over rough countryside, and it’ll carry heavier loads further. So now you had a work animal and a transport animal. And by this time there was plenty to transport, because they were producing so much, they had a surplus.

You see, at the same time as all this, a new crop system came in: the idea of using three fields—the three-crop rotation system it’s called. One field is fallow, so the animals can graze on it and drop manure on it. One field is sown in the autumn with cereals like oat, for example, to feed the horses. And one field is sown in the spring with legumes—peas, beans. Carbohydrates, vegetable protein. This was why they dropped the longbow. Because when you have enough food to sell the surplus for cash, you’ve better things to do on a Sunday than obey the law and practice archery. People went into business, they opened taverns, they even played games. That’s why they couldn’t find any archers: nobody was practicing. They were too full of beans!

Now, this may look very simple and rustic to you, but what you’re looking at is the Medieval peasant equivalent of “thank god it’s Friday!” But all the more so, because they’d never had one before—a day off, I mean. Thanks to the agricultural revolution and the opening up of new land with the plow, there were actually spare goodies a peasant could take to market and sell for that amazing new stuff, money. All over Europe, the Medieval lower classes started doing something absolutely unheard of: they started enjoying themselves. Some of them even started washing.

The reason for all this dynamic activity was because, as Europe recovered from the chaos and confusion of the tenth century, prosperity—if I could just have your attention for a moment—prosperity encouraged trade, and merchants began to travel around selling anything they could get people to buy. Between 1150 and 1300 the population tripled. Towns grew up. So did the number of craftsmen and professions. And so did the paperwork and the bureaucracy.

If you think about it, these must’ve been great days for most of them. Enough cash to buy things with, paying the landlord rent instead of forced labor, justice (perhaps) at the new village law courts, even a little personalized medical treatment. It may have been a bit rough, but it was better than nothing—well, almost. Okay, so a peasant couldn’t get to be a prince, but he could expect his kids to grow up to a better life.

Meanwhile, as the rustic rollicking continued, in the King’s palace it was lead balloon time. I mean, here were all these hayseeds committing the unforgivable sin of not doing their duty, which was to work until they dropped and practice the longbow on Sundays—remember the longbow? It took a lot of practice to make a good archer who’d go out and get himself slaughtered for you, and these idiot’s weren’t getting the practice. It began to look to the kings and princes as if you couldn’t go out and have yourself a nice old-fashioned war anymore.

And then, good old human ingenuity came up with a less demanding way to kill people. Now, to be fair to the Europeans, they didn’t actually invent it. But they took to its immense destructive potential with all the gay abandon of an alcoholic in a brewery. And in case you’re wondering why I’m telling you all this with my pig friends here, it’s because one of the first places they found the principal ingredient for the new terror weapon was in a pigsty. Why? Well, you see, a pig’s home is also his toilet. And you make gunpowder from urine and dung.

Using that kind of muck to get to this lethal powder involved going through a bit of chemistry first. The urine became ammonia, and the bacteria in the dung turned the ammonia into a nitrate. Having mixed the mess with wood ash, and then filtered water through it all, boiling that water produced saltpeter crystals. This powder is a mixture of saltpeter, sulfur, and charcoal. All you do now is apply a flame, stand very far back, and…!

Gunpowder was a Chinese invention. And they had it maybe 700 years before we in the West got our hands on it. And it’s very probable we only got it because the Arabs picked it up in China and brought it back with them, like they did with so many Chinese ideas. It’s very likely that whoever it was who invented gunpowder, he was one of their philosopher-chemists actually searching for the secret recipe for immortality. Ironic, isn’t it? In the main, apart from the odd rocket or grenade, that was how the Chinese used their gunpowder: for fireworks in religious rituals.

Which brings us (for a minute or two) to the business about the Chinese inventing everything, and yet not using it the way we did. This is part of the reason: their view of life.

The thing that surprises us in the West—because we use everything we can get hold of to cause change to happen—is that the Chinese had so much, and changed so little. What I mean by “so much” is this: they had gunpowder (you saw), and look what we did with that. And then, 2,000 years ago, they used to spin magnetic spoons on pictures of the Earth and the sky, and depending which way the spoon pointed when it stopped, they made a political prediction. When we got a hold of that in the form of a compass needle, we used it to conquer the world, to set up empires—aided in our voyages by a Chinese rudder. Chinese looms, capable of making complex patterns like that, helped to set up the great thirteenth-century European textile industries. A thousand years before us, the Chinese had blast furnaces, steel, pistons, cranks, and this—paper.

Part of the reason why, in spite of all this, change didn’t come in China the way it did when all this came to the West was this. Not printing—although they invented that, too. No. This word: Tao (道). It means “the universal way,” “the fundamental order of nature.” The Taoist scholars were a group who looked for some rational order in things, to see how the universe worked, and (because of their investigations) gave China what we would call technology.

And yet, explosive change—the kind we in the West went through when we got hold of what China had invented—didn’t happen here. And to explain why I’m going to have to hit you with a bit more of inscrutable Chinese philosophy. You see, the Chinese believed that the universe was filled with shen, a spirit that was in everything, and that all you could do was contemplate it. Trees, mountains, birds, rivers were all one, and so you couldn’t reproduce a model of the bit of the universe and examine it, because you couldn’t fill it with shen. Now, in the Christian West we reckoned that the universe was made of rational bits and pieces by a rational god, and if you were a rational human being you could make a model of a bit of the universe, and then take it apart to see how it worked, and use what you learned.

The other fundamental reason why change didn’t happen here in China was that: water. You see, about 5,000 years ago, the very first great civilized act of the Chinese was irrigation on a vast scale. And that needed centralized planning, and that needed a bureaucracy. And what a bureaucracy! They pigeonholed everybody, and you stayed in your pigeonhole. I mean, you were a merchant, you saw a bit of technology, and you thought, “Ha! This’ll give me a lead over the other fellow! I’ll rise in the world.” No way. You were not permitted to rise in the world. So you didn’t bother. No incentive, no change. Whereas, in the Medieval West, you had a little money, you got ahead. Profit motive, you know? And that is why we were able to do with technology what the Chinese could never have done—like, for instance, putting gunpowder into one of these. Or, to be more accurate, one of those.

The fact that bell-making was a peaceful religious business didn’t stop thirteenth-century Europeans from grabbing the idea. Look how easy it was to adapt. And the bell becomes a bombard—instant artillery. For the princes and generals, happily, it was business as usual once more.

This picturesque little town called Cividale, near the Yugoslav border, was one of the first places where the exciting new way of killing people was tried out in 1327 by a bunch of passing Germans. Now, early on, the new guns made more bang and smoke than real destruction, and each cannon could only be fired about ten times a day. But a mere mention that guns were on their way was enough to make a town surrender. Well, what more could you ask? In no time at all, everybody wanted one to play with.

Which is why our story brings us here, to a place called Jáchymov in the mountains of northern Czechoslovakia. It was the growing mania everybody had for cannons that built this place and turned it into the sixteenth-century Fort Knox of Europe. You see, few inventions have ever been more greedily seized on than the cannon. And in consequence, the business of making war became ruinously expensive—not in terms of men, they were cheap—in terms of money. And all the way through the late Middle Ages that was the one thing that they were short of: cash. Until, in 1516, here in Joachimsthal (as it was called at the time), the biggest silver strike in history was made out there in the valley. At its peak, Joachimsthal was turning out something like three million ounces of pure silver a year. And they were minting these, here in this building, as fast as the stamping machines would make them. They were called after a shortened form of the name of the town—Joachimsthal—Talers. The modern word “Dollar” comes from “Taler.” And just like the Dollar today, in their time, these Talers would buy you anything you wanted anywhere you went. Well, you can guess what happened. From all over Europe, miners and speculators flooded into this place seeking their fortune up there among the pine trees.

In these mountains the prospectors found no less than 134 separate silver veins, each one richer in the precious ore than the last. Some of the mines had tunnels running seven miles long and shafts going down to 1,200 feet. The cost of the mining operations and water-powered machinery to crush the ore and smelt it was so great that no one individual could afford it. So Joachimsthal became the first great capitalist venture with shareholders forming companies to run the place. And as the water flowed, the mill wheels roared, and the hammers pounded, the owners of these lonely mountain mining villages made money hand over fist.

Ever occurred to you why so much mining so often took place in these high, cold, wet mountain valleys? Trees is one reason. They built everything from trees. The trees provided the fuel for the blast furnaces. And then, when it poured or snowed—which it very often does here—the mountain streams would turn the water wheels that operated every single bit of machinery a mining engineer needed. And the reason we know what kind of machinery they used is this: it’s a book written by the local Joachimsthal town doctor, a fellow called George Bauer. He wrote it under the pen name of Agricola. It’s called De re metallica: “About Metal.” And it was the miner’s bible for 200 years after it was published in 1556.

Look: it talks about everything. Above all, it talked about how you get water out of a mine. Because as they went deeper and deeper, the problem of flooding became a nightmare. They had water-powered systems to handle it, but at the lowest levels the water was pouring in as fast as they drained it.

They had three principal ways of getting it out. One was to use a chain with balls of cloth on it, and the cloth would soak the water up at the bottom and they’d squeeze it out at the top. The other way was to use a standard system of buckets. The third and most efficient way was this. See, here’s the water wheel operating either on the surface or down in the mine, and using a system of cranks to pull piston rods up and down. It’s a suction pump. But look how they had to do it in three different sections. Now, that was because, for some mysterious reason, they couldn’t get the water further up than 32 feet. It would go that far and then it would stop.

Now, with that amount of silver at stake, everybody wanted to find out why. So finally somebody wrote to Galileo. And Galileo put his pupil Torricelli onto it, and Torricelli cracked it. He reckoned that it had something to do with the fact that the air above the surface of the water down in the mine wasn’t heavy enough to, so to speak, help the water up the tube. And he reckoned that if you built yourself a mini-model using heavy mercury in a small tube to represent the real thing—32-foot tube, ton of water—you could study the thing scientifically.

So he wrote all this out in a letter which he sent to his friend Ricci, who lived in Rome. Diagrams, details, the lot. Now, Ricci knew that whatever it was, it involved the investigation of the vacuum. And Rome was far too close to the Pope for that kind of thing. The church said there was no such thing as a vacuum, and if you did, then you could find yourself suddenly dead. So Ricci—clever lad—copies out the one section of the letter that has to do with the guts of it and sends it via a French friend to somebody who is in a position to talk about the vacuum. The letter was sent to Father Marin Mersenne in Paris. And Mersenne was exactly the right man to send it to.

First of all, because he was in Paris and a long way from the Pope. And second of all, because he was a scientific monk with the biggest address book in the seventeenth century. With his contacts, he wanted something fixed, he fixed it. He was known as the “postbox of Europe” because everybody would write to him with their ideas and he’d spread the word around. In this case he mentioned the matter to a friend of his who was going to be passing through the town of Rouen.

Interesting, the business of communications. We take it so much for granted today. I mean, this French postal van—it’s so common a sight as to be almost invisible. And yet, it’s because we can communicate so easily that change happens so fast. Something new? Television tells everybody. And in Mersenne’s time in the seventeenth century, the new postal services made a real impact on the spread of ideas and the changes that happened because people could contact each other. Like in this case, for example.

The message finally got to Rouen in northwest France, to a certain Blaise Pascal, who went out immediately to the nearest glass factory and carried out Torricelli’s experiment. He took a glass tube filled with mercury, and he put his finger over the open end, and then he inverted the tube and put the open end into a dish of mercury. And when it was in it, he took his finger away. And there, inside the tube, was the thing the church said couldn’t exist: a vacuum. What’s more, Pascal agreed with Torricelli that the weight of the air pressing on that mercury there must be the same as the weight of the mercury in the glass tube to keep it standing up here like that.

So if air pressure really existed, was it the same everywhere? He looked around for a mountain, and there were no mountains in Rouen. But his brother in law lived here, where I am now: in Clermont-Ferrand, in the center of France, where there are tons of mountains. So Pascal wrote another letter. And finally, in September 1648, his brother in law did as he’d been asked: he took this lot 4,000 feet up to the top of a mountain called Puy de Dôme—after marking the level, of course, first.

At the top he observed the tube in fog like this, in rain, in shine, indoors and out. And in each place the level stayed stubbornly the same: about three inches below what it had been at the bottom of the hill. So the air pressure up here on the dish of mercury was less because it would only support that much mercury instead of that much. Everybody was delighted. They’d invented the barometer. This is one of those moments in history when, because this has happened, the field’s wide open. You can go in any direction. Vacuum research, meteorology, investigation of gases. But the route we’re going to take happened because a man was on the night shift.

This is a foggy night in gay Paris, 1675, and this is a foggy French astronomer, Jean Picard. On his way home from his observatory, Picard was jauntily swinging his new barometer when, suddenly: [electrical discharge]. Picard was stunned. Zut alors! he thought, and told everybody, and kicked off a century of international insanity. In England, Francis Hauksbee cranked a glass globe ’round and ’round and got this. The more he rubbed his glass balls, the weirder things got. They became strangely attractive. In 1679 he told everybody, so they all started doing it.

Around 1720, Stephen Gray was rubbing a glass tube to make it attractive—well, why not?—when he saw that the attraction went down a thread attached to the tube. In 1745 somebody found a way to store up the mysterious force in a jar full of water. Electricity was now portable. There was no holding the intrepid investigators. The big question now was: what exciting things could you do with sparks?

German ladies of… evident charms… were placed in special chairs connected to a Hauksbee machine. And when a good, stiff charge had been cranked up, young men were invited to try their luck. A fat German investigator called Hausen used the same machine to do similarly electrical things to small suspended boys. A flamboyant French friar called Knowles, who gave private courses in electricity to beautiful women and couldn’t get out of the habit, decided to run a charge through multiple monks to see if the effect would produce an uplifting experience. It did!

Well, it seemed obvious that electricity was good for you. And in 1780, the famous temple of electrical health opened in London. Star of the show: the magnetico-electrico celestial bed where (accompanied by an orchestra) electrified couples who couldn’t have children could, thanks to the inevitable cranking of the Hauksbee generator. You wanted ringside seats, you bought tickets. In spite of all the ballyhoo, the bed failed and its owner went off and sold mud baths. Still, others persevered.

Around 1783, an Italian called Luigi Galvani was poking around with a metal scalpel one day—oh, it’s alright, it’s only frog’s legs; I guess he was fond of frogs—when suddenly the leg lying on a metal plate jerked. Galvanized by this discovery, Galvani announced animals made electricity. In 1800 another Italian—with the electrical name of Volta—got it right. Volta saw that the electricity came from reaction between Galvani’s scalpel and the metal in the plate under the frog. So he built a pile of differing metal plates and got electricity; called it his pile.

Well, now our looneys had Volta’s pile to give them constant electricity, there was no stopping them! Various attempts were made to send current down wires which would cause pith balls to swing. Each wire and ball represented a letter, and a message could be read off the other end. They actually got it going between Madrid and a town 26 miles away. Then came a really zany one. If you put an electrified wire into water, it makes bubbles. So yes, you’ve guessed it: a German doctor used the bubbles to send messages. Things ended in typical chaos when somebody tried electricity with gunpowder.

By the beginning of the nineteenth century, things became very much more purposeful than that. And although an awful lot of innovation and change comes about by accident, by mistake, cheating, fooling around, it sometimes happens because people find something out that sets them thinking. And that’s what happened in this case. In 1820, a rather dull Dane called Ørsted was teaching his students that an electric current going down a wire shouldn’t have any effect whatsoever on a compass needle when, to his utter chagrin, it did. Well, no fool he, Ørsted had immediately made it known that if an electric current going down a wire caused a compass needle to swing, it had to be generating a magnetic field and moving the needle. Poor old Ørsted. I mean, who’s ever heard of him? Michelangelo, yes. Ørsted?

And yet, the fact that an electric current generates a magnetic field is fundamental to the way the world is run today. I mean, take just one thing that happened because of Ørsted. If you wind a live wire ’round and ’round a bit of iron, the magnetic field generated by the current causes the iron to become a magnet—an electromagnet. Now, somebody did that in England in 1825. In 1857, a German took a tuning fork and put it next to an electromagnet, turned it on and off—turned the magnetic field on and off—and caused the tuning fork to vibrate. And then, in 1870, a Frenchman living in America took a diaphragm, put a bristle on the end of it, and then yelled into the diaphragm to make it vibrate, and the bristle jiggled up and down and made a pattern on smoked glass. And the pattern was always the same for the same word.

Now, I say all this because the brilliant invention that came out of it—and it was a brilliant invention—was really no more than putting all those bits and pieces together. Like this: you yell into that cone. That causes a metal diaphragm here to vibrate. Now, that metal diaphragm is within this magnetic field, and as it vibrated kind of drains it, causing the current in the live wire to fluctuate. This fluctuating current fluctuates a wire until it reaches an identical setup where, because it’s a fluctuating current, it makes a fluctuating magnetic field. And that causes another metal diaphragm to vibrate in exactly the same pattern as the first one. And when it does that, it makes a noise in that cone. So what you yell in here comes out there.

Now, that basic idea occurred to two men at the same time. Only, one of them—a Scotsman living in Boston in 1875, teaching deaf mutes—got to the patent office two hours ahead of the other fellow. And that two hour difference is why we say that the telephone was invented by Alexander Graham Bell.

The telephone was only one result of Ørsted’s accident with that compass needle. Another is our ability to scan the universe with this giant antenna, suspended above a reflector that covers an entire valley 500 feet below.

Another is the way this program has been broadcast: on radio waves. Or the way we defend ourselves against attack from incoming missiles with radar. Because both radio and radar work by sending out and receiving electromagnetic signals. And it was Ørsted who found that connection between electricity and magnetism.

It’s ironic that this program should have begun with war—with the bomb in the suitcase and the stirrup, remember?—and end with the means of preventing war through the use of telecommunications, perhaps to bring the peoples of the world closer together into one community. And finally, perhaps, to discover that we are part of an infinitely larger community on the day when a transmitter/receiver, like this one in Arecibo in Puerto Rico, makes contact with the galactic civilization that are almost certainly out there in space.

Meanwhile, as we wait for the great encounter, at a more down-to-Earth level, what will the capacity that telecommunication provides of organizing people do to us?