0:00:03 > 0:00:07Every day our lives collide with thousands of things.
0:00:10 > 0:00:13Some seem rather simple, others, we take for granted.
0:00:15 > 0:00:19'But the trappings of modern life and the materials they're made from
0:00:19 > 0:00:21'have transformed the way we live.
0:00:21 > 0:00:24'Giving us comfort, pleasure
0:00:24 > 0:00:26'and power.
0:00:26 > 0:00:29'Behind them is a story of hidden transformations,
0:00:29 > 0:00:32'proof that we live in an age of miracles...'
0:00:32 > 0:00:34This is nothing less than levitation.
0:00:36 > 0:00:40'..where the weak and fragile can become the super strong...'
0:00:41 > 0:00:45'..where parts of the human body can be built by machines.'
0:00:45 > 0:00:48I mean, that feels like science fiction.
0:00:48 > 0:00:52'These are the innovations that have transformed our world...'
0:00:52 > 0:00:54I mean, it's just so audacious!
0:00:54 > 0:00:56I can't believe they actually did it.
0:00:56 > 0:00:59'..the materials that have allowed us to create a world we enjoy.'
0:00:59 > 0:01:01It's already feeling comfy.
0:01:03 > 0:01:05'The visionaries who made it happen
0:01:05 > 0:01:09'turned new materials into miracles of mass production...'
0:01:09 > 0:01:11Look, baby seals!
0:01:11 > 0:01:13'..that define the modern world.'
0:01:13 > 0:01:15Look at that, weow weow weow!
0:01:15 > 0:01:18'I'll be recreating their genius in the lab,
0:01:18 > 0:01:22'and investigating the properties of the remarkable things they created,
0:01:22 > 0:01:25'the everyday miracles that have transformed our homes,
0:01:25 > 0:01:28'our world, and ourselves.'
0:01:30 > 0:01:33Last time, I discovered how advances in modern production
0:01:33 > 0:01:36have transformed our homes.
0:01:36 > 0:01:39This time, I'll be stepping out of the home and exploring
0:01:39 > 0:01:41the everyday miracles that have transformed our experience
0:01:41 > 0:01:42of the world.
0:01:44 > 0:01:48Helping us travel further and faster, to have fun,
0:01:48 > 0:01:51to discover the secrets of the universe,
0:01:51 > 0:01:54and even to better understand ourselves.
0:02:08 > 0:02:11The minute you step outside a whole new world
0:02:11 > 0:02:13of exciting possibilities opens up.
0:02:16 > 0:02:18There's something very human about wanting to know what's over
0:02:18 > 0:02:21the next hill or out to sea, over that horizon.
0:02:24 > 0:02:26And not just to know what's there but to go there yourself,
0:02:26 > 0:02:27to explore.
0:02:29 > 0:02:33My own exploration of the world started in 1986
0:02:33 > 0:02:35when I set off for France on my bike.
0:02:37 > 0:02:40The whole world seemed in reach back then,
0:02:40 > 0:02:43all we had to do was keep pedalling.
0:02:43 > 0:02:46We didn't though, we got the ferry back to Dover
0:02:46 > 0:02:49where I got arrested because I'd lost my passport.
0:02:52 > 0:02:56Looking back, I can see how much I took for granted in my teens.
0:02:56 > 0:03:00Like my bike, an amazing machine that could, in theory,
0:03:00 > 0:03:04take me anywhere in the world.
0:03:04 > 0:03:07What I hadn't realised at the time was how much of the human journey,
0:03:07 > 0:03:10our ability to explore this planet and other planets,
0:03:10 > 0:03:14is down to our ability to transform materials that this planet provides.
0:03:26 > 0:03:29I still love riding my bike today, especially
0:03:29 > 0:03:32because it's packed full of material science innovation which all
0:03:32 > 0:03:37came about relatively recently, which is odd because the bicycle
0:03:37 > 0:03:41seems to me like something that should've been around forever.
0:03:45 > 0:03:48Of course the bicycle hasn't always been with us.
0:03:48 > 0:03:50In fact it hasn't been with us for very long.
0:03:50 > 0:03:51It was this man,
0:03:51 > 0:03:55Baron Karl von Drais, who set the ball rolling in 1820,
0:03:55 > 0:04:00and he invented something called the laufmaschine and this is it.
0:04:00 > 0:04:03It has two wheels, a frame, handles,
0:04:03 > 0:04:07and it was designed to help you get around, but you had to run.
0:04:13 > 0:04:16Hence the word laufmaschine, because lauf is the German for run.
0:04:22 > 0:04:25Designed to support a fully-grown baron,
0:04:25 > 0:04:30the laufmaschine was little more than a wooden bench on wheels.
0:04:30 > 0:04:33It's sturdy frame took the bulk of your weight,
0:04:33 > 0:04:36but you could still only travel at running speed.
0:04:36 > 0:04:41It was nearly half a century before that was bettered, by this,
0:04:41 > 0:04:43the boneshaker.
0:04:43 > 0:04:46In 1870 this was the cutting edge of bicycle design.
0:04:48 > 0:04:52It's made of wrought iron and wood, but critically has pedals.
0:04:52 > 0:04:57The bonus is more speed, but now stopping's the issue,
0:04:57 > 0:04:59so I'm pleased they added at least some rudimentary brakes.
0:05:03 > 0:05:08But it was still far removed from the modern bicycle.
0:05:08 > 0:05:11Although the boneshaker is so much better than what came before it,
0:05:11 > 0:05:13essentially it's still pretty hopeless.
0:05:13 > 0:05:18I mean, it's really heavy! I'm not putting that on, it weighs a tonne!
0:05:18 > 0:05:23It's slow, it's cumbersome, it's difficult to manoeuvre.
0:05:23 > 0:05:28It's just... It looks beautiful but it's not really the thing you want.
0:05:28 > 0:05:31What you want is this...
0:05:32 > 0:05:35..the kind of bike people were riding just 18 years
0:05:35 > 0:05:38after the boneshaker was invented.
0:05:38 > 0:05:41I've got one, it's light, stiff and strong, it's essentially
0:05:41 > 0:05:46a modern bike, but its basic design dates back to the 1880s.
0:05:47 > 0:05:49And the reason it is light, stiff and strong is
0:05:49 > 0:05:54because of the steel tubing and the pneumatic tyres,
0:05:54 > 0:05:57and what made those possible is not so much an innovation
0:05:57 > 0:06:01in engineering or design, it's the emergence of new materials.
0:06:02 > 0:06:05In the mid 1800s, Henry Bessemer discovered how to turn
0:06:05 > 0:06:08iron into high-strength steel on a massive scale.
0:06:09 > 0:06:12That transformed industry and launched a new era of tools
0:06:12 > 0:06:14and machinery.
0:06:16 > 0:06:19Unlike iron, steel could easily be made into tubes,
0:06:19 > 0:06:24though at first they had welded seams and weren't very strong.
0:06:24 > 0:06:28Then, in 1886, a way to make tubes without the seam was invented,
0:06:28 > 0:06:30and so the bicycle had its frame.
0:06:31 > 0:06:33It also had its chain.
0:06:33 > 0:06:37In 1880, industrial steel was used to make a revolutionary
0:06:37 > 0:06:39roller-chain, which also made gears possible.
0:06:41 > 0:06:44But the best was yet to come, the bicycle tyre.
0:06:46 > 0:06:51John Dunlop invented his pneumatic tyre in 1888 to give his son's
0:06:51 > 0:06:54tricycle a comfier ride than its traditional solid wheels did.
0:06:57 > 0:06:58He took rubber,
0:06:58 > 0:07:01made rigid by the process of vulcanisation with sulphur,
0:07:01 > 0:07:04and he used it in a brilliant way
0:07:04 > 0:07:08to create a semi-rigid, air-filled tyre.
0:07:08 > 0:07:11It was an ingenious idea that's been used on pretty much every bike
0:07:11 > 0:07:15made since, and almost anything else with wheels.
0:07:17 > 0:07:20What's amazing is how those simple materials innovations
0:07:20 > 0:07:22utterly transformed the bicycle.
0:07:24 > 0:07:27To show just what a revolution in design the 1880s bike was
0:07:27 > 0:07:30compared to its predecessor, the boneshaker,
0:07:30 > 0:07:33I've brought them both here to Herne Hill velodrome
0:07:33 > 0:07:34for a rather unusual race.
0:07:40 > 0:07:42These racing cyclists are going to help me out...
0:07:44 > 0:07:47..by comparing the boneshaker to its successor.
0:07:53 > 0:07:55Wow, that was impressive, very, very, very speedy.
0:07:55 > 0:07:57So I've got a challenge for you guys.
0:07:57 > 0:07:59I'm just wondering what kind of lap times could you do on this?
0:07:59 > 0:08:01LAUGHTER
0:08:01 > 0:08:04I think you'd be looking at days, rather than seconds.
0:08:04 > 0:08:08Well, if it takes 30 or 40 seconds to do a lap on one of these
0:08:08 > 0:08:11machines it's going to take at least double if not triple,
0:08:11 > 0:08:13maybe more, you know, two or three minutes?
0:08:13 > 0:08:16Trying to set the bar high so that you can then come underneath that
0:08:16 > 0:08:19- and really impress. - LAUGHTER
0:08:24 > 0:08:27Club-racer Nigel is going to ride the boneshaker in a head-to-head
0:08:27 > 0:08:30pursuit against me.
0:08:30 > 0:08:32I'll be on the post-1880s bicycle.
0:08:34 > 0:08:37So we've got a super fit athlete on a boneshaker,
0:08:37 > 0:08:41and me on a bike designed just a few years later but featuring
0:08:41 > 0:08:45pneumatic tyres and tubular steel, not to mention the roller-chain.
0:08:47 > 0:08:49We're starting on opposite sides of the track,
0:08:49 > 0:08:51and we'll try to catch each other up.
0:08:53 > 0:08:54- Are you ready, Nige?- Yeah.
0:08:54 > 0:08:56- Tony?- Ready.
0:08:58 > 0:09:01Go, Nige! Come on! Come on, Nige!
0:09:03 > 0:09:06He's getting up big speed now, getting stability.
0:09:06 > 0:09:09Yeah, it touch more than a minute, guys.
0:09:11 > 0:09:12CLASSICAL MUSIC
0:09:16 > 0:09:17DRAMATIC MUSIC
0:09:21 > 0:09:22CLASSICAL MUSIC
0:09:28 > 0:09:30DRAMATIC MUSIC
0:10:00 > 0:10:01Here he comes.
0:10:08 > 0:10:11It's the most difficult machine I've ever cycled on,
0:10:11 > 0:10:13without a shadow of a doubt.
0:10:13 > 0:10:17- I wouldn't be swapping it for my road bike any time soon.- No.
0:10:20 > 0:10:22Sadly, I can't claim any credit for my victory.
0:10:25 > 0:10:28I owe it all to the revolution in materials that transformed
0:10:28 > 0:10:32the bicycle from a cumbersome novelty to a genuine speed machine.
0:10:35 > 0:10:37With its squishy tyres
0:10:37 > 0:10:41and tubular steel frame, the bicycle was no longer difficult to ride.
0:10:44 > 0:10:47Where just a few years earlier you needed huge thighs
0:10:47 > 0:10:50and a death wish, now anyone could be a cyclist.
0:10:53 > 0:10:56Heavily marketed to Victorian women, it's sometimes argued
0:10:56 > 0:11:00the bicycle played a crucial role in female emancipation.
0:11:08 > 0:11:11In truth, they offered us all new-found freedom.
0:11:15 > 0:11:17Suddenly our social circles increased,
0:11:17 > 0:11:20we could travel three or four times faster,
0:11:20 > 0:11:24and three or four times further than we could by foot,
0:11:24 > 0:11:27and as our horizons expanded we met and married people
0:11:27 > 0:11:29from further afield.
0:11:29 > 0:11:32With the advent of pneumatic tyres and tubular-steel frames
0:11:32 > 0:11:35the nation's gene pool got a major mix up.
0:11:41 > 0:11:44The bicycle was a good idea but it was waiting for the right
0:11:44 > 0:11:48materials to come along, and when they did it took off in a big way.
0:11:48 > 0:11:51I mean, you only have to look at the Dunlop tyre company, right,
0:11:51 > 0:11:55that exploded from nowhere into a global, multimillion pound
0:11:55 > 0:11:58business just on the back of bicycle tyres.
0:11:58 > 0:12:02So the story of the bicycle is good design meeting new materials
0:12:02 > 0:12:03and making history.
0:12:07 > 0:12:09It's a story that plays out
0:12:09 > 0:12:12time and time again in the history of transport.
0:12:13 > 0:12:17When motorcars came along they promised unimaginable freedom,
0:12:17 > 0:12:18even compared to the bicycle.
0:12:20 > 0:12:24This is a Sunbeam motorcar, it was built in 1903 in Wolverhampton.
0:12:26 > 0:12:27It's liberation!
0:12:30 > 0:12:33But, just as with bicycles, there was something missing from the first
0:12:33 > 0:12:37cars that meant they suffered from a rather grave limitation.
0:12:38 > 0:12:39It's quite slow.
0:12:42 > 0:12:44One of the things that limited the speed
0:12:44 > 0:12:48and success of cars like this was the lack of comfort.
0:12:48 > 0:12:52Completely open to the elements, you have to cope with a face
0:12:52 > 0:12:56full of wind, rain, dirt and insects.
0:12:56 > 0:12:59And any faster than 30mph feels like being punched in the face.
0:13:01 > 0:13:04To reach their full potential cars relied on the evolution
0:13:04 > 0:13:07of a material that's often overlooked,
0:13:07 > 0:13:10possibly because you're not really supposed to see it at all.
0:13:11 > 0:13:12Glass.
0:13:23 > 0:13:25Because of glass' transparency and its hardness
0:13:25 > 0:13:28and strength it's the perfect material for a windscreen.
0:13:28 > 0:13:31I mean, look, I can speed along here, I'm not buffeted by the wind,
0:13:31 > 0:13:34I don't have to care about the rain.
0:13:34 > 0:13:37Although, apart from all those great characteristics, it does have
0:13:37 > 0:13:39rather one unpleasant one.
0:13:42 > 0:13:44It shatters.
0:13:44 > 0:13:47So although the first glass windscreens did keep out
0:13:47 > 0:13:52the wind, in an accident they also produced flying shards of glass
0:13:52 > 0:13:54that sliced through motorists like daggers...
0:13:56 > 0:13:58..which wasn't ideal.
0:14:07 > 0:14:12To make viable windscreens we needed a way to transform glass,
0:14:12 > 0:14:16to keep all its benefits, but ditch the lethal hazard.
0:14:16 > 0:14:19There are a couple of ways of making glass safer,
0:14:19 > 0:14:21one is to toughen the outside by rapidly cooling it.
0:14:22 > 0:14:26That's how these were made, they're called Prince Rupert's drops.
0:14:28 > 0:14:31Named after the Bavarian prince who first brought them
0:14:31 > 0:14:33to Britain in the 17th century.
0:14:36 > 0:14:39They're made by dropping molten glass into water.
0:14:43 > 0:14:45And that gives you this sort of droplet shape,
0:14:45 > 0:14:47and does something very interesting to the outside because
0:14:47 > 0:14:51the outside immediately solidifies while the inside is still molten.
0:14:51 > 0:14:54This sets up a series of internal forces
0:14:54 > 0:14:57because as the molten interior solidifies
0:14:57 > 0:14:58it pulls the outside in,
0:14:58 > 0:15:02and that creates compression forces on the outside
0:15:02 > 0:15:06which can withstand quite large forces, including a hammer blow.
0:15:06 > 0:15:08And if you don't believe me,
0:15:08 > 0:15:11and in some senses I don't believe it either because it seems
0:15:11 > 0:15:15so ridiculous that you should hit a piece of glass with a hammer
0:15:15 > 0:15:17and it would survive, but let's give it a go anyway.
0:15:17 > 0:15:20Glass drop, meet hammer.
0:15:28 > 0:15:31It's impressive, but not indestructible.
0:15:33 > 0:15:36If I can disturb the balance between the internal tension forces
0:15:36 > 0:15:40and the external compression forces it'll set up a chain reaction,
0:15:40 > 0:15:43an explosion, and the whole thing will disintegrate.
0:15:43 > 0:15:46So let's see if that works, by just snapping the tail off.
0:15:48 > 0:15:49Oh, yeah, it works!
0:15:51 > 0:15:55As the stress is released countless fractures spread through the drop
0:15:55 > 0:15:59in an instant, creating a cloud of tiny fragments.
0:16:02 > 0:16:05The key thing is that these tiny pieces are nowhere near
0:16:05 > 0:16:07as lethal as the long blades of glass
0:16:07 > 0:16:10that breaking the first windscreens produced.
0:16:15 > 0:16:17There you have it, safety glass.
0:16:30 > 0:16:33For hundreds of years this remarkable form of glass
0:16:33 > 0:16:35had little practical use.
0:16:35 > 0:16:38That is until the age of the car.
0:16:44 > 0:16:48This glass is toughened in much the same way as a Prince Rupert's drop.
0:16:48 > 0:16:53So how it works is that the pane of glass is cooled rapidly
0:16:53 > 0:16:54as it's solidifying.
0:16:56 > 0:16:57But when it does go...
0:17:00 > 0:17:02..all of that in-built tension
0:17:02 > 0:17:05is released in one go and you get this multiple shattering effect.
0:17:07 > 0:17:10And the advantage to that is that the glass turns into tiny
0:17:10 > 0:17:14little shards and each one of them, yeah, could scratch you but
0:17:14 > 0:17:17it isn't a shard of glass that's going to go through an artery
0:17:17 > 0:17:22and so this kind of glass has made car crashes much more safe.
0:17:24 > 0:17:27The windscreen is toughened in a different way.
0:17:30 > 0:17:33Now there's a sheet of plastic sandwiched between two pieces
0:17:33 > 0:17:34of glass in this windscreen,
0:17:34 > 0:17:38and it's that plastic that's holding all the shards of glass together.
0:17:38 > 0:17:40This is the essence of bullet proof glass,
0:17:40 > 0:17:43although in bullet proof glass there's four or five different layers.
0:17:53 > 0:17:55Glass windscreens are an everyday miracle
0:17:55 > 0:17:58that's revolutionised travel around the planet for all of us.
0:18:01 > 0:18:03But that's not the only way glass has helped us
0:18:03 > 0:18:05explore further from home.
0:18:11 > 0:18:14It has also helped us to travel in another sense,
0:18:14 > 0:18:17to reach out further from home than any other material has
0:18:17 > 0:18:21allowed us to do, by exploring the entire universe.
0:18:29 > 0:18:32But once again these great leaps were only made possible
0:18:32 > 0:18:36by manipulating glass, by exploiting its properties
0:18:36 > 0:18:40in numerous ways to drive the evolution of the telescope.
0:18:43 > 0:18:47The power of simple glass lenses was realised 500 years ago.
0:18:52 > 0:18:56In 16th century Venice, Galileo used the light-bending
0:18:56 > 0:19:00properties of glass to make telescope lenses, and with them
0:19:00 > 0:19:04confirmed that the planets all orbit the sun, rather than the Earth.
0:19:04 > 0:19:07He'd revealed our planet was not the centre of all things,
0:19:07 > 0:19:10which made the Catholic Church pretty cross.
0:19:11 > 0:19:14In Holland, shortly after, Antoni Van Leeuwenhoek made
0:19:14 > 0:19:19glass microscope lenses and by examining pond water, pepper,
0:19:19 > 0:19:24and even his own sperm, discovered an unknown miniature world.
0:19:24 > 0:19:27These remarkable properties of glass launched us on a new journey
0:19:27 > 0:19:31of exploration that would eventually overturn our sense of scale and
0:19:31 > 0:19:35give us a totally new perspective on our place in the universe.
0:19:40 > 0:19:43Glass lenses meant the universe was no longer limited
0:19:43 > 0:19:45to what the naked eye could see.
0:19:48 > 0:19:52But to begin with astronomers struggled to make big lenses,
0:19:52 > 0:19:55glass was often tinted and full of bubbles,
0:19:55 > 0:19:59while primitive grinding techniques made it hard to get them the right shape.
0:20:03 > 0:20:06It wasn't until the 19th century that lens technology
0:20:06 > 0:20:09had improved enough to make telescopes that were seriously big.
0:20:14 > 0:20:16But, even as they were being built,
0:20:16 > 0:20:19they'd reached the end of their potential.
0:20:21 > 0:20:24This is the Northumberland Telescope at Cambridge University
0:20:24 > 0:20:27and was once the biggest telescope in the world.
0:20:27 > 0:20:31And despite all this enormous engineering complexity
0:20:31 > 0:20:34it's actually quite a simple object, it's got a large magnifying lens
0:20:34 > 0:20:37at one end and an eyepiece at the other.
0:20:37 > 0:20:41You simply point it where you want to see in the night sky.
0:20:41 > 0:20:45It was a must-have piece of equipment for the gentleman scientist of the day.
0:20:47 > 0:20:51The glass lens at the top of this telescope is huge
0:20:51 > 0:20:53and that's what makes it so sensitive,
0:20:53 > 0:20:56able to peer into the dim distance better than any before.
0:20:58 > 0:21:02But sadly, this is pretty much the size limit for a refracting telescope,
0:21:02 > 0:21:05and what limits it are the properties of the glass lens.
0:21:07 > 0:21:09First, glass is heavy.
0:21:11 > 0:21:14All this engineering stuff around it
0:21:14 > 0:21:17is to support this huge weight, and also to allow you to
0:21:17 > 0:21:22manipulate it so you can point to different parts of the sky.
0:21:22 > 0:21:25But worse still, as the size of the lens increases,
0:21:25 > 0:21:29so does the effect of another unfortunate property of glass.
0:21:33 > 0:21:37Lenses work by bending light, and it's the bending that gives you
0:21:37 > 0:21:41the magnification, but when you bend white light it splits it up into
0:21:41 > 0:21:45its many colours, as Newton showed with his famous prism experiment.
0:21:47 > 0:21:50Look, you can create all the colours of the rainbow,
0:21:50 > 0:21:53and Newton explained why, it's because different colours
0:21:53 > 0:21:57of light travel at different speeds through the glass.
0:21:57 > 0:22:01In a lens this blurring and distorting of colour is called chromatic aberration.
0:22:03 > 0:22:06The bigger the lens, the bigger the problem,
0:22:06 > 0:22:07and the worse the telescope.
0:22:10 > 0:22:13It became clear that although glass had given astronomers
0:22:13 > 0:22:16so much in the form of this telescope,
0:22:16 > 0:22:20to go any further they would have to get rid of glass lenses altogether.
0:22:22 > 0:22:26They turned instead to metal, although glass would
0:22:26 > 0:22:30eventually return to play quite a different role in telescopes.
0:22:31 > 0:22:35There are two ways to magnify an image, one uses a convex lens,
0:22:35 > 0:22:38and the other uses a concave mirror, like this.
0:22:40 > 0:22:44The glass in a mirror like this is only there to give it shape,
0:22:44 > 0:22:46it's the silvered backing that reflects,
0:22:46 > 0:22:49and as it's curved like a spoon, also magnifies.
0:22:52 > 0:22:56For astronomy you can use a polished metal mirror that has
0:22:56 > 0:23:00no glass on top, which means no chromatic aberration.
0:23:05 > 0:23:08This is a reflecting telescope, in which all the magnification
0:23:08 > 0:23:12is done by a polished metal mirror mounted at the bottom.
0:23:13 > 0:23:17This telescope is much more powerful than the one next door
0:23:17 > 0:23:20and that's because its magnifying element, in this case a mirror,
0:23:20 > 0:23:23is much bigger, so it's collecting more light.
0:23:23 > 0:23:27And as well as being free from chromatic aberration
0:23:27 > 0:23:31a big metal mirror is much lighter than a big glass lens.
0:23:31 > 0:23:34And also it's much easier to support down here
0:23:34 > 0:23:38so that gives you the capacity of making bigger telescopes
0:23:38 > 0:23:40with more magnification that can see further.
0:23:43 > 0:23:47With a metal mirror it seemed at first that telescopes could be
0:23:47 > 0:23:50any size you wanted, and by the 20th century some mirrors were up to
0:23:50 > 0:23:552.5 metres across, but at that size a new problem arose,
0:23:55 > 0:24:00it became increasingly hard to keep the mirror in shape.
0:24:02 > 0:24:06For a telescope reflector to work properly it mustn't distort.
0:24:06 > 0:24:09The problem is that most materials expand or contract with
0:24:09 > 0:24:12temperature and deform under their own weight.
0:24:13 > 0:24:15Things get worse as the mirror gets bigger.
0:24:19 > 0:24:23Astronomers' mirrors were made from huge blocks of quartz rock,
0:24:23 > 0:24:25with a reflective layer of metal on top.
0:24:27 > 0:24:30Not even the worst temperature swings could deform solid quartz.
0:24:33 > 0:24:36But in 1928 astronomer George Hale set about building
0:24:36 > 0:24:41the biggest ever telescope mirror, twice the size of any before.
0:24:41 > 0:24:44The trouble was, no-one could make a quartz mirror that big.
0:24:46 > 0:24:48So the race was on to find a material to build
0:24:48 > 0:24:51the record-breaking five metre reflector.
0:24:51 > 0:24:54In the end the answer was glass.
0:24:56 > 0:25:01But this glass didn't come from an optics lab,
0:25:01 > 0:25:04it came from the kitchen.
0:25:04 > 0:25:08In 1915 American cooks had been amazed at the arrival
0:25:08 > 0:25:09of see-through saucepans.
0:25:11 > 0:25:13They'd been invented by the Corning Glass Company
0:25:13 > 0:25:17of New York, using a new weather-proof glass
0:25:17 > 0:25:21they'd developed for railway lanterns, called Pyrex.
0:25:21 > 0:25:24It was made heat-proof by adding a metalloid element called boron.
0:25:28 > 0:25:29Easier to work with than quartz
0:25:29 > 0:25:31and with excellent thermal properties,
0:25:31 > 0:25:35this was just the stuff for Hale's telescope mirror.
0:25:40 > 0:25:43Scaling up operations from their normal kitchenware production,
0:25:43 > 0:25:46the Corning Glass Company took on the task of making
0:25:46 > 0:25:51the monolithic Pyrex mirror using 20 tonnes of borosilicate glass.
0:25:54 > 0:25:59After months of cooling the mirror set off on its 3,000 mile journey
0:25:59 > 0:26:03to California, at a very safe 25mph all the way.
0:26:05 > 0:26:10It took another 13 years to grind into shape,
0:26:10 > 0:26:12briefly interrupted by World War II,
0:26:12 > 0:26:17then in 1949, polished smooth to within two millionths of an inch,
0:26:17 > 0:26:22it was finally winched into position in the giant telescope dome.
0:26:23 > 0:26:27For 30 years the glass mirror coated with metal remained the biggest
0:26:27 > 0:26:29and the most powerful in the world.
0:26:31 > 0:26:35With it astronomers measured the distance to our nearest galaxy
0:26:35 > 0:26:39and discovered quasars, the oldest and most distant objects ever seen.
0:26:41 > 0:26:45Thanks to glass the size of the known universe had grown
0:26:45 > 0:26:47almost beyond human comprehension.
0:26:54 > 0:26:57Glass has allowed us to discover more about ourselves,
0:26:57 > 0:27:01our world, our universe than almost any other material.
0:27:01 > 0:27:02From the lenses of our microscopes,
0:27:02 > 0:27:05to the reflectors of our giant telescopes,
0:27:05 > 0:27:09glass has expanded our horizons more than we had any right to hope for.
0:27:14 > 0:27:19Meanwhile, back in the world of everyday materials our horizons
0:27:19 > 0:27:24had been expanded in a different way by a new material that many describe
0:27:24 > 0:27:28as among the greatest innovations to emerge from the 20th century.
0:27:31 > 0:27:34There's a long history of combining materials to create completely new
0:27:34 > 0:27:39ones, they're called composites, for example wattle and daub, concrete,
0:27:39 > 0:27:42plywood, as well as more exotic combinations of metals and plastics.
0:27:42 > 0:27:45But there's a spectacular new composite which is allowing
0:27:45 > 0:27:49industrial designers to completely reinvent some objects,
0:27:49 > 0:27:50and even change lives.
0:27:52 > 0:27:54It's called carbon fibre composite.
0:27:57 > 0:28:01Nicky Maxwell is 17 and has his sights set on Paralympic glory.
0:28:05 > 0:28:08Nicky has a single below-the-knee amputation.
0:28:09 > 0:28:12His athletic career has been transformed by carbon fibre composite
0:28:12 > 0:28:15in the form of his remarkable,
0:28:15 > 0:28:17high performance running blade.
0:28:19 > 0:28:23But it's not just in athletics where carbon fibre's had an impact on prosthetics.
0:28:26 > 0:28:28This is the first prosthetic that I had,
0:28:28 > 0:28:31you'll notice obviously it doesn't have a foot on it of any kind.
0:28:31 > 0:28:35- Here's one with a foot, though. - This was World Cup 2006.- Oh, right.
0:28:35 > 0:28:37The ankle here is still rigid
0:28:37 > 0:28:39but the foot is made of a rubber that does have
0:28:39 > 0:28:42a bit of flex in it, so it's making your gait a bit more fluid.
0:28:42 > 0:28:46I guess the first time that I got a non-rigid ankle would've been this,
0:28:46 > 0:28:50and inside this foot there are a few different C-shaped curves of carbon
0:28:50 > 0:28:53which enable the foot to compress and bend in different directions.
0:28:53 > 0:28:56- So this has got carbon fibre in it? - So this has got a little bit in it, yeah.
0:28:58 > 0:29:02Nicky's racing leg is made entirely of carbon fibre composite.
0:29:04 > 0:29:07It has boosted his performance beyond all recognition
0:29:07 > 0:29:11with its winning formula of lightness, strength and rigidity,
0:29:11 > 0:29:14all tuned to put the perfect amount of spring in Nicky's step.
0:29:17 > 0:29:21So what does that blade give you that other prosthetics don't?
0:29:21 > 0:29:24Well, fundamentally what you have to appreciate is how much work
0:29:24 > 0:29:27your lower leg, particularly your calf, does when you're walking
0:29:27 > 0:29:30or running, so your calf really, it generates a lot of power.
0:29:30 > 0:29:33So a blade like this, which is effectively a spring,
0:29:33 > 0:29:35it really helps to simulate that.
0:29:35 > 0:29:38So that movement of landing on your foot
0:29:38 > 0:29:40and really pushing off the spring will compress and take in
0:29:40 > 0:29:43that energy and then push back and it gives it back out again.
0:29:47 > 0:29:50With his blade Nicky can look forward to enjoying athletics
0:29:50 > 0:29:53in a way that only a few years ago would have been impossible.
0:29:53 > 0:29:57But this is only one in a long line of applications.
0:29:57 > 0:30:00Carbon fibre composite has become the material of choice
0:30:00 > 0:30:06wherever weight, strength and performance are important.
0:30:06 > 0:30:08Whether that's snowboards,
0:30:08 > 0:30:11tennis racquets,
0:30:11 > 0:30:13or golf clubs.
0:30:14 > 0:30:18And carbon fibre has completely replaced steel in the bodywork of racing cars.
0:30:24 > 0:30:29When the Bloodhound Supersonic car attempts to rocket to a 1000mph land-speed record...
0:30:32 > 0:30:35..the driver will sit in a carbon fibre cockpit.
0:30:39 > 0:30:42And in aeronautical engineering the future's carbon, too.
0:30:45 > 0:30:48The latest airliners use carbon fibre to reduce weight
0:30:48 > 0:30:49and save fuel.
0:30:53 > 0:30:56So what's the secret to carbon fibre's success,
0:30:56 > 0:30:58its light weight and strength?
0:31:02 > 0:31:05This is the stuff that makes carbon fibre composite strong,
0:31:05 > 0:31:09it's individual strands of carbon filaments, incredibly fine.
0:31:13 > 0:31:18Finer than hair, but per weight ten times stronger that steel.
0:31:18 > 0:31:22Doesn't look it, I know, but I've taken a length of it here
0:31:22 > 0:31:24and I'll show you what I mean.
0:31:25 > 0:31:28Let's see if I can get it to take my weight.
0:31:28 > 0:31:34So there's a small strand of it, got a little swing here, here we go.
0:31:37 > 0:31:40Attach that there. Get through there.
0:31:40 > 0:31:42I know what you're thinking,
0:31:42 > 0:31:45I don't weigh very much, but actually I do, surprisingly enough.
0:31:51 > 0:31:55Right, now the lifting legs off the ground, here we go.
0:32:00 > 0:32:03Yes! No problem at all.
0:32:06 > 0:32:08So that's pretty impressive, isn't it?
0:32:08 > 0:32:12I mean, tiny little threads of carbon, finer than my hair,
0:32:12 > 0:32:14holding my whole weight.
0:32:15 > 0:32:18It's incredibly strong, but it does have one defect.
0:32:21 > 0:32:24It is after all a thread which means that although it's very strong in
0:32:24 > 0:32:27this direction as we've seen, if you push it, well,
0:32:27 > 0:32:29it just bends all over the place,
0:32:29 > 0:32:32so if you really want to replace steel and metals
0:32:32 > 0:32:34to make engineering objects out of it,
0:32:34 > 0:32:37you need to find a way of stopping those fibres from bending,
0:32:37 > 0:32:41and the way to do that is to cover it in plastic.
0:32:41 > 0:32:44And a particular kind of plastic works really well called an epoxy,
0:32:44 > 0:32:46and that's what it looks like,
0:32:46 > 0:32:50and we just take a bit of epoxy, and epoxy in itself isn't that strong.
0:32:52 > 0:32:57In fact it's very brittle, unless you reinforce it with carbon fibre.
0:33:05 > 0:33:07You can really have a go at this.
0:33:10 > 0:33:13Take my word for it, it is the business.
0:33:15 > 0:33:19Making a composite component is pretty straightforward.
0:33:19 > 0:33:24This tape has thousands of carbon fibres running along its length,
0:33:24 > 0:33:27once I've wound it around this cardboard tube all
0:33:27 > 0:33:29I have to do is coat it with a layer of epoxy plastic.
0:33:38 > 0:33:41And when that epoxy sets we get this...
0:33:43 > 0:33:45..a tube that's light
0:33:45 > 0:33:46and very stiff.
0:33:47 > 0:33:49But it's not yet strong.
0:33:52 > 0:33:56And the reason for that is because as we wrapped it round
0:33:56 > 0:33:59the mandrill all of the fibres are aligned in one direction,
0:33:59 > 0:34:02so it's strong across the circumference
0:34:02 > 0:34:06but it's not strong in tension which is what happens when I bent this.
0:34:06 > 0:34:09So the way to sort that out is to come back to this.
0:34:10 > 0:34:14If I add another layer of carbon but wrap it in the other direction,
0:34:14 > 0:34:17now the tube is encased in a crisscross of fibres.
0:34:19 > 0:34:22So, when you do that several times back and forth
0:34:22 > 0:34:25you can build up strength in many different directions.
0:34:25 > 0:34:27And in fact that is the key to carbon fibre composites,
0:34:27 > 0:34:29is to work out where your stresses are
0:34:29 > 0:34:33and to align the fibres to withstand the stress in that direction only.
0:34:33 > 0:34:36So you're only putting the material in where you need it.
0:34:36 > 0:34:40And once you've done that several times you end up with
0:34:40 > 0:34:45something like this which is a bit heavier,
0:34:45 > 0:34:47still incredibly stiff, but this time...
0:34:50 > 0:34:52..really strong.
0:34:52 > 0:34:54I think we need to do the standard weight test.
0:34:56 > 0:35:03Let's see if this can take my weight. Yep, no problem.
0:35:05 > 0:35:09That gives designers almost complete flexibility, building in extra
0:35:09 > 0:35:13strength where it's needed but saving on weight where it's not.
0:35:16 > 0:35:19One perfect illustration of that is the new generation of
0:35:19 > 0:35:21high performance racing bikes.
0:35:23 > 0:35:27This is the latest carbon fibre bicycle frame as used
0:35:27 > 0:35:29by professional cyclists in races like the Tour De France.
0:35:29 > 0:35:33It's incredibly light, weighs only 800 grams.
0:35:33 > 0:35:35It's hard to get a sense of what 800 grams is,
0:35:35 > 0:35:39it's sort of the weight of a bunch of bananas,
0:35:39 > 0:35:42so let's see if it's...yeah.
0:35:42 > 0:35:47So that's how light it is, it's head-scratchingly amazing,
0:35:47 > 0:35:52and what the material allows you to do is pare the whole thing down.
0:35:52 > 0:35:55So down here these struts, they look flimsy but they're not,
0:35:55 > 0:35:58they're stiff, they're strong, along here where
0:35:58 > 0:36:03you don't need so much strength you can actually physically deform it.
0:36:03 > 0:36:07It's a wonderful material which gives industrial designers complete flexibility.
0:36:09 > 0:36:14Carbon fibre is fast becoming the ultimate construction material in the everyday world.
0:36:21 > 0:36:25But there are also miracles made possible by much more exotic
0:36:25 > 0:36:29and unusual materials, and one of those is MRI scanning.
0:36:33 > 0:36:36MRI is now a standard diagnostic technique,
0:36:36 > 0:36:40an everyday miracle, but we couldn't have MRI without huge
0:36:40 > 0:36:44magnetic fields, and we couldn't have huge magnetic fields
0:36:44 > 0:36:47without strange materials that allow you to do this.
0:36:49 > 0:36:51This is nothing less than levitation,
0:36:51 > 0:36:54I mean, it's a delight to watch, you'd never get tired of it.
0:36:59 > 0:37:02What makes this levitate are these little grey discs.
0:37:04 > 0:37:06They are known as superconductors
0:37:06 > 0:37:08and it is superconductivity that allows us
0:37:08 > 0:37:12to make the kind of huge magnetic fields required for MRI scanning.
0:37:16 > 0:37:19Superconductivity is all about cooling things down.
0:37:22 > 0:37:23Let me show you what I mean.
0:37:25 > 0:37:29I've got a very long coil of wire here, a light, and some batteries,
0:37:29 > 0:37:33when I connect the whole circuit up have a look what happens.
0:37:33 > 0:37:36When I connect the battery the bulb hardly lights,
0:37:36 > 0:37:39and that's because the resistance of the long coil is so high,
0:37:39 > 0:37:41very little electricity flows.
0:37:43 > 0:37:46But, over here, I have a flask of liquid nitrogen
0:37:46 > 0:37:48and I can cool that coil of wire down.
0:37:58 > 0:38:01As it cools down the light's getting brighter and brighter
0:38:01 > 0:38:03and brighter so the resistance
0:38:03 > 0:38:06to the flow of electricity in the wire is decreasing.
0:38:07 > 0:38:11This lowering of resistance happens in all conductors,
0:38:11 > 0:38:13but get a superconductor cool enough
0:38:13 > 0:38:17and electricity can flow completely freely.
0:38:17 > 0:38:19That's the definition of a superconductor,
0:38:19 > 0:38:21something with no electrical resistance.
0:38:23 > 0:38:28And that makes some very odd things possible, like levitation.
0:38:30 > 0:38:32Inside here are some superconductors
0:38:32 > 0:38:34and they're being cooled by this liquid nitrogen.
0:38:34 > 0:38:39It's about minus 200 degrees in there so it is very cold.
0:38:39 > 0:38:42The track below is magnetic, and that magnetic field
0:38:42 > 0:38:46makes electricity flow on the surface of the superconductor.
0:38:49 > 0:38:53And what that's doing is creating small currents that then create
0:38:53 > 0:38:56a magnetic field, and that magnetic field's
0:38:56 > 0:38:59repelled by this magnetic field on the bottom here.
0:38:59 > 0:39:04So this is a very special effect and it only happens when it's very cold.
0:39:04 > 0:39:07But while it is cold, it will defy gravity forever.
0:39:09 > 0:39:11The current that is created on the surface of the grey disk
0:39:11 > 0:39:13generates a magnetic field,
0:39:13 > 0:39:17and that magnetic field is exactly the same one in the track,
0:39:17 > 0:39:20so they repel each other perfectly, and because it's a superconductor
0:39:20 > 0:39:24with no electrical resistance this will happen indefinitely.
0:39:26 > 0:39:29It's this lack of resistance in superconductors
0:39:29 > 0:39:33that also allows us to make ultra efficient electromagnets.
0:39:33 > 0:39:35Making an electromagnet is pretty easy.
0:39:35 > 0:39:38You just need to wrap wire around something iron,
0:39:38 > 0:39:42this nail will do, and connect the wire to a battery.
0:39:42 > 0:39:49But if I put a current through it, then I magically get one,
0:39:49 > 0:39:55and take it away, and put it back on again, and away.
0:39:55 > 0:40:00To get a really powerful magnet you need more coils of wire,
0:40:00 > 0:40:04but the more coils of wire you use the less electricity will flow,
0:40:04 > 0:40:09like in the bulb, but if the wire was superconducting there would be
0:40:09 > 0:40:14no resistance and really huge magnetic fields could be produced.
0:40:14 > 0:40:16And that's what you find in MRI scanners.
0:40:16 > 0:40:19The coils in these electromagnets are cooled
0:40:19 > 0:40:23to four degrees above absolute zero by bathing them in liquid helium.
0:40:24 > 0:40:27The magnetic field produced is so strong that it's able to
0:40:27 > 0:40:30align aspects of a hydrogen atom in living tissue in the same direction.
0:40:32 > 0:40:35Hydrogen atoms in different tissues will return
0:40:35 > 0:40:38to their magnetised positions at different rates when they're
0:40:38 > 0:40:42briefly disturbed by a secondary field, and by measuring that rate of
0:40:42 > 0:40:45change it's possible to build up a picture of where they are in
0:40:45 > 0:40:49the body, and ultimately to produce a picture of the body itself.
0:40:53 > 0:40:56Our understanding of the stuff our world is made from
0:40:56 > 0:41:00has helped us understand ourselves at the very smallest level,
0:41:00 > 0:41:03and detailed knowledge of how things are put together
0:41:03 > 0:41:06and how they can be imaged, recorded and replayed,
0:41:06 > 0:41:10has started to change the way we can reproduce and manufacture objects.
0:41:18 > 0:41:20For the entire history of making things,
0:41:20 > 0:41:22there have been two key challenges.
0:41:22 > 0:41:25Whether it's a bicycle or a telescope mirror
0:41:25 > 0:41:27you need to find the right material for the job,
0:41:27 > 0:41:30but you also have to work out how to fashion it into the shape you want.
0:41:32 > 0:41:35From striking flint or carving stone or wood,
0:41:35 > 0:41:40or machining and casting metals, that final stage, manufacture,
0:41:40 > 0:41:44has always limited the possibilities of practical design.
0:41:49 > 0:41:52But imagine if you could dream up an object of any shape
0:41:52 > 0:41:55and make it materialise in front of you at the push of a button.
0:41:55 > 0:41:58Well, that idea isn't a fantasy,
0:41:58 > 0:42:00it's what I think will be tomorrow's everyday miracle.
0:42:00 > 0:42:04It's with us now and it's called 3D printing.
0:42:04 > 0:42:07With it comes the promise of a new era in design where we'll be limited
0:42:07 > 0:42:09only by our imagination.
0:42:11 > 0:42:14These are 3D printers, they're rather disappointing-looking
0:42:14 > 0:42:19boxes of various sizes, but what they do is anything but boring.
0:42:20 > 0:42:23What they allow you to do is print objects,
0:42:23 > 0:42:25and how that works is this -
0:42:25 > 0:42:29you create the object digitally on a computer, so here's an example of
0:42:29 > 0:42:34an object created, it's got a three-dimensional form, it's hollow.
0:42:34 > 0:42:37Something like this would be very pretty much impossible to make using
0:42:37 > 0:42:40a mould, but all I have to do here is load the file onto the system.
0:42:41 > 0:42:45And then you press print, and then out it comes, it's marvellous.
0:42:47 > 0:42:50How it works is that the computer will divide this object
0:42:50 > 0:42:52up into different layers,
0:42:52 > 0:42:55and each one of those layers is printed on this printer.
0:42:55 > 0:42:58It doesn't work so differently from a normal 2D printer
0:42:58 > 0:43:01but instead of printing ink it prints plastic.
0:43:07 > 0:43:11I've got some things here which have been made using a 3D printer
0:43:11 > 0:43:12to show you what you can do.
0:43:12 > 0:43:13Have a look at this.
0:43:15 > 0:43:20Now this, it seems like an almost impossibly complex mechanism.
0:43:20 > 0:43:23If you were to try to make this another way, let's say carve it out
0:43:23 > 0:43:27of wood or machine it out of metal, you'd have to be extremely skilled.
0:43:27 > 0:43:30But with 3D printing all you need is the digital file,
0:43:30 > 0:43:33and you press print. And because the printing is
0:43:33 > 0:43:37so precise it can produce almost impossibly intricate shapes, too.
0:43:38 > 0:43:39Or take a look at this.
0:43:39 > 0:43:43This was printed in one piece, it's a piece of chain mail,
0:43:43 > 0:43:48it's got fabric-like qualities, it's exquisite, there are no joins.
0:43:48 > 0:43:51And it's not just plastic, you can print in metal,
0:43:51 > 0:43:54you can print in ceramic, you can print electronics.
0:43:54 > 0:43:57I mean, the possibilities for this technology are really endless.
0:44:04 > 0:44:073D printing is a powerful new technology which has
0:44:07 > 0:44:10the potential to radically change manufacturing,
0:44:10 > 0:44:12but here in Nottingham University there's a group of scientists
0:44:12 > 0:44:15who are using it for something quite different.
0:44:15 > 0:44:193D printing is no less than the ultimate manipulator of materials,
0:44:19 > 0:44:22the ultimate manufacturing tool
0:44:22 > 0:44:25that can be applied to almost anything.
0:44:27 > 0:44:29'Kevin Shakesheff...'
0:44:29 > 0:44:31- Hello.- Hey, nice to see you. - Yeah, you too.
0:44:31 > 0:44:34'..is perhaps the most unusual manufacturer I've met.
0:44:34 > 0:44:36'He's a materials scientist, just like me.'
0:44:38 > 0:44:41Yeah, this definitely looks like a materials science lab.
0:44:41 > 0:44:43- There's a mechanical tester, it must be one.- Yeah, yeah.
0:44:46 > 0:44:49But unlike me his specialism is human flesh.
0:44:54 > 0:44:56Yeah, I feel very envious of biology
0:44:56 > 0:44:59because it has this one Lego block called the cell
0:44:59 > 0:45:02and it can turn into bone, or it can turn into your skin, or it can turn
0:45:02 > 0:45:07into something transparent like an eye, that seems to me sort of magic.
0:45:07 > 0:45:10Yeah, I think that's what really drew me into the subject.
0:45:10 > 0:45:14The key to 3D printing human body parts are a particular
0:45:14 > 0:45:16type of cell called stem cells.
0:45:16 > 0:45:19These cells are in the first stage of development
0:45:19 > 0:45:22and can grow into all different types of tissue in the body.
0:45:22 > 0:45:25The first stage of Kevin's process is to tell stem cells
0:45:25 > 0:45:29which tissue to grow into, and to dictate what shape they form.
0:45:29 > 0:45:32The secret is the physical properties of the material
0:45:32 > 0:45:34the stem cells are growing on.
0:45:34 > 0:45:37What a cell becomes is determined by its environment around it,
0:45:37 > 0:45:41so if we think of a very soft tissue like skin tissue or brain tissue,
0:45:41 > 0:45:44we use something very soft, so we've got materials which
0:45:44 > 0:45:48can mimic the mechanical properties of these tissues.
0:45:48 > 0:45:49And what is that?
0:45:49 > 0:45:52This is actually a material called alginate which
0:45:52 > 0:45:55comes from seaweed, good for growing tissues like...
0:45:55 > 0:45:57Yeah, I love this stuff. Lovely gel.
0:45:57 > 0:46:01Tissues like cartilage grow quite well in that environment,
0:46:01 > 0:46:04but it's not right for bone, it's completely different to bone.
0:46:04 > 0:46:07So then we use a different material type which is much harder,
0:46:07 > 0:46:09if you want to have that,
0:46:09 > 0:46:12and the material itself acts as what we call a scaffold.
0:46:17 > 0:46:20This means that if you make a replacement body part
0:46:20 > 0:46:23out of the right material and lace it with stem cells,
0:46:23 > 0:46:26those cells can become the type of tissue required.
0:46:28 > 0:46:32So we'll go and have a look at the printer which is through in this room.
0:46:33 > 0:46:36Using a 3D printer Kevin can make any shape
0:46:36 > 0:46:38required in the right material.
0:46:40 > 0:46:43The plastic this printer is using makes stem cells want to
0:46:43 > 0:46:47grow into the right type of tissue, in this case for a replacement nose.
0:46:49 > 0:46:52So you're printing things that cells are going to live in,
0:46:52 > 0:46:55for implants in the body,
0:46:55 > 0:46:58and the shape is determined presumably by the patient?
0:46:58 > 0:47:00There are patients who have a tumour in the nose
0:47:00 > 0:47:05and that entire nose structure has to be removed surgically.
0:47:05 > 0:47:07So the idea is you can take a scan of that structure.
0:47:07 > 0:47:09That's the file there?
0:47:09 > 0:47:11This a file that's been created from scanning them.
0:47:11 > 0:47:13So those are the nostrils, right?
0:47:13 > 0:47:14So this is the bottom of the nose.
0:47:14 > 0:47:17Yeah, it's starting from the bottom and working its way up,
0:47:17 > 0:47:20- and that takes a couple of hours to form the final structure.- Wow, yeah.
0:47:20 > 0:47:23But you have that sort of structure there.
0:47:25 > 0:47:29The printed nose is temporary, it provides a scaffold into
0:47:29 > 0:47:32which stem cells can be injected, and because the scaffold has
0:47:32 > 0:47:36the right properties, the stem cells will turn into the right tissue.
0:47:40 > 0:47:42That is quite impressive.
0:47:42 > 0:47:45I mean, that feels like science fiction, I mean,
0:47:45 > 0:47:50so where could we go, I mean how far, like, kidneys, livers, hearts?
0:47:50 > 0:47:53The interesting thing with all of those tissues is you grew them
0:47:53 > 0:47:56yourself when you were an embryo so the cells are there
0:47:56 > 0:47:59and have some instructions to know how to do it.
0:47:59 > 0:48:03The printers are getting very close to being able to achieve
0:48:03 > 0:48:07the overall structure, so if we combine those two together,
0:48:07 > 0:48:12I'm optimistic that we could print all of those structures,
0:48:12 > 0:48:15or certainly components of them, to help patients.
0:48:15 > 0:48:18This gives a whole new meaning to the nose job, doesn't it?
0:48:26 > 0:48:30For me this is one of the most beguiling things about materials,
0:48:30 > 0:48:33you never know what they're going to turn into.
0:48:35 > 0:48:36It's inconceivable that
0:48:36 > 0:48:40when plastics burst onto the scene 100 years ago that anyone would
0:48:40 > 0:48:43have predicted they would lead to printed organs.
0:48:45 > 0:48:49Or that tubular steel would provide the bicycle, or that telescopes
0:48:49 > 0:48:52and the key to the universe would emerge from glass.
0:48:54 > 0:48:59But time and again these everyday miracles impact our lives and our world.
0:49:00 > 0:49:04Sometimes they pop up apparently overnight,
0:49:04 > 0:49:07but sometimes they evolve so slowly that it's only with
0:49:07 > 0:49:10the benefit of hindsight that their impact can be seen clearly.
0:49:12 > 0:49:18My final miracle is just that, something that has evolved,
0:49:18 > 0:49:22drawing in new materials and changing the way that old ones are used.
0:49:23 > 0:49:27This is the river that separates Edinburgh from the north of Scotland,
0:49:27 > 0:49:30from the great cities of Perth, Dundee and Aberdeen.
0:49:30 > 0:49:34For more than 900 years people have been ferried across this river,
0:49:34 > 0:49:36but you don't need a boat now.
0:49:43 > 0:49:45This is the Forth bridge,
0:49:45 > 0:49:49it was opened in 1890 to take trains across the river.
0:49:51 > 0:49:52It still does.
0:49:52 > 0:49:5554,000 passenger trains
0:49:55 > 0:49:59and ten million tonnes of freight cross here every year.
0:50:00 > 0:50:02It's absolutely magnificent.
0:50:02 > 0:50:07I mean, it's just so audacious, I can't really believe...
0:50:07 > 0:50:09I can't believe they actually did it.
0:50:13 > 0:50:17It was a wonder of its age, made possible only
0:50:17 > 0:50:21because of new technology producing high quality steel.
0:50:25 > 0:50:29The huge tubular trapeziums of its structure are made from
0:50:29 > 0:50:35thousands of individual steel plates held together by millions of rivets.
0:50:37 > 0:50:41The steel bridge across the River Forth transformed the Victorian
0:50:41 > 0:50:45transport network, but soon the train wasn't the only way to travel.
0:50:45 > 0:50:47Motorcars were just around the corner
0:50:47 > 0:50:50and people started agitating for a road bridge.
0:50:55 > 0:50:58And this is what they got.
0:50:59 > 0:51:02The Forth road crossing. It's a suspension bridge,
0:51:02 > 0:51:04a completely different type of bridge design.
0:51:04 > 0:51:08The central span is more than 1,000 meters long
0:51:08 > 0:51:11and the road is 50 meters above the water level.
0:51:12 > 0:51:15It's an extraordinary structure, it's so elegant.
0:51:23 > 0:51:25Much of that elegance comes from the material.
0:51:25 > 0:51:29It wouldn't have been possible without advanced steel making methods.
0:51:29 > 0:51:32Our understanding of how to make steel that was both stronger
0:51:32 > 0:51:34but more reliably uniform.
0:51:37 > 0:51:40This bridge is made of steel just like the railway bridge,
0:51:40 > 0:51:42but construction techniques have moved on,
0:51:42 > 0:51:46much larger pieces of steel can now be made.
0:51:46 > 0:51:49It's a wonderful example of how improved materials can give
0:51:49 > 0:51:51designers new opportunities.
0:51:53 > 0:51:56The higher quality steel used in a new bridge made the design possible,
0:51:56 > 0:52:03and weighing in at 40,000 tonnes it uses less steel to the tune of 10,000 tonnes.
0:52:04 > 0:52:09And it took a much reduced workforce a year less to build than the first one.
0:52:19 > 0:52:23Now they're building a new bridge, they're still using steel
0:52:23 > 0:52:26but they're using it in a different way, and they're adding in
0:52:26 > 0:52:31a totally different material - concrete, in vast quantities.
0:52:31 > 0:52:34The incredible thing about this bridge is that they've
0:52:34 > 0:52:35created a mould...
0:52:37 > 0:52:39..and they're pouring in concrete.
0:52:43 > 0:52:45And up it rises from the river bed.
0:52:47 > 0:52:52The third Forth crossing is a completely new design to the other two.
0:52:52 > 0:52:55It's a cable stay bridge, which means that instead of being
0:52:55 > 0:52:58suspended from wires the road section will be
0:52:58 > 0:53:02hung from steel cables attached directly to the concrete towers.
0:53:02 > 0:53:05This is easier to build and means that
0:53:05 > 0:53:08if a cable fails it can be easily replaced,
0:53:08 > 0:53:12whereas if a suspension cable fails the whole bridge is compromised.
0:53:14 > 0:53:18But before the cables go in the towers themselves must be poured,
0:53:18 > 0:53:23a mammoth task overseen by engineer, Jaime Castro.
0:53:24 > 0:53:27So how much concrete are you going to be pouring here?
0:53:27 > 0:53:29Well this tower, and then in each of these towers will be
0:53:29 > 0:53:319,000 cubic metres of concrete.
0:53:32 > 0:53:36Of course concrete itself is nothing new, but you can see here
0:53:36 > 0:53:39how it's being poured around a skeleton of reinforcing steel rods.
0:53:42 > 0:53:44It's a technique that has made concrete the ultimate
0:53:44 > 0:53:47and most-used construction material in the world.
0:53:50 > 0:53:53Reinforced concrete has revolutionised
0:53:53 > 0:53:57the way our homes are built and how our infrastructure is constructed.
0:53:57 > 0:54:01Its versatility comes from combining the huge tensile strength
0:54:01 > 0:54:05of steel with the enormous compression strength of concrete.
0:54:06 > 0:54:09- What's this? - So, that's the concrete barge,
0:54:09 > 0:54:13that's how we get the concrete here, and we pump it through the tower
0:54:13 > 0:54:16until the concrete is actually in centre, until it goes in the top.
0:54:16 > 0:54:18- Nice, nice, can we have a look?- Yes.
0:54:20 > 0:54:24The concrete, mixed on the shore-side and brought out by barge,
0:54:24 > 0:54:28is pumped continuously into the latest section of the mould,
0:54:28 > 0:54:32day and night, until the section is full and can be left to cure,
0:54:32 > 0:54:34when the process is repeated.
0:54:34 > 0:54:37When they're finished the towers will stand
0:54:37 > 0:54:39over 200 meters above the water.
0:54:39 > 0:54:43So we're in a unique position here cos we can see the first bridge
0:54:43 > 0:54:46over there, built more than 100 years ago, and here's
0:54:46 > 0:54:49the second bridge, and now you're building the third bridge.
0:54:49 > 0:54:52- Is this as good as it gets in building technology? - Well, it is now.
0:54:52 > 0:54:56In the future, in 100 years, materials will change,
0:54:56 > 0:54:58innovation will come along, who knows?
0:54:59 > 0:55:03Of course he's right, and even if the same building
0:55:03 > 0:55:06materials are used, the way they're used will doubtless move on.
0:55:08 > 0:55:11The steel that's being used for the bridge deck here is a far cry
0:55:11 > 0:55:15from the steel that's riveted together in the railway bridge.
0:55:18 > 0:55:20So how does this differ to the previous bridges
0:55:20 > 0:55:23in terms of its construction materials and techniques?
0:55:23 > 0:55:25I mean, first of all it's a much higher grade of steel.
0:55:25 > 0:55:29I would say almost 100% stronger than what we have used in the other bridges.
0:55:29 > 0:55:33And I guess you're benefiting as a professional from 100 years
0:55:33 > 0:55:36or more of bridge-building, you can really pare down where you need
0:55:36 > 0:55:40the material, and that reduces costs but also makes it more elegant.
0:55:40 > 0:55:41Yes, it is.
0:55:41 > 0:55:44I mean, if you look at this steel section, we have 12mm steel
0:55:44 > 0:55:48out here, there in the middle you can have up to 100mm, before
0:55:48 > 0:55:52they didn't have those kind of tools in order to differentiate like that.
0:55:52 > 0:55:55If you compare it to other bridges in the world we are stepping up.
0:55:55 > 0:55:58Every single time we do a new bridge we are increasing the quality
0:55:58 > 0:55:59and increasing the strength of it.
0:56:01 > 0:56:04And that's what these bridges show us,
0:56:04 > 0:56:07the everyday miracle that is progress through materials.
0:56:09 > 0:56:12The bare facts reveal a lot.
0:56:12 > 0:56:16The first Forth bridge took eight years to build, the second six,
0:56:16 > 0:56:18the last one will take five.
0:56:18 > 0:56:23At its peak, 4,500 men worked on the first bridge.
0:56:23 > 0:56:26In the latest version the most people working on site
0:56:26 > 0:56:28at any one time is just 1,200.
0:56:30 > 0:56:32And another advance is safety.
0:56:32 > 0:56:37On the first bridge the 98 worker deaths were considered almost inevitable.
0:56:37 > 0:56:41No serious injuries have occurred or are anticipated on this latest build.
0:56:52 > 0:56:56It's astonishing to think that over the past 100 years or so
0:56:56 > 0:56:59our understanding of materials, of what our planet provides for us,
0:56:59 > 0:57:03has not just changed the way we live our lives, but has also
0:57:03 > 0:57:08fundamentally changed the way we see our home, and ultimately ourselves.
0:57:11 > 0:57:15We're a curious species and our mastery of materials has meant that
0:57:15 > 0:57:19we've been able to take our curiosity to hitherto unimagined
0:57:19 > 0:57:23heights, providing unthought-of solutions to age-old problems.
0:57:24 > 0:57:28This bridge across the Firth of Forth is emblematic of the human spirit.
0:57:28 > 0:57:31In a way it tells you all you need to know about who we are.
0:57:31 > 0:57:34We make this stuff and it's hugely impressive.
0:57:34 > 0:57:37Faced with the engineering challenge of crossing a huge swathe
0:57:37 > 0:57:41of water, we've had to understand how to transform materials, and
0:57:41 > 0:57:45that's allowed us not just to build bridges but to explore the world,
0:57:45 > 0:57:48the solar system, the universe, and even inside our own brains.
0:57:48 > 0:57:51It's those brains of course that've conceived new materials to
0:57:51 > 0:57:54make a new bridge, and I can't wait to drive over it.
0:57:54 > 0:57:57I'm so excited, it's going to be beautiful.
0:57:57 > 0:58:00Of course, 30 years ago it wouldn't have been possible to build it, and
0:58:00 > 0:58:04that's the thing about materials, we keep inventing new ones.
0:58:04 > 0:58:08And that allows us to reinvent the future, to go new places,
0:58:08 > 0:58:10to discover new things.
0:58:11 > 0:58:13Who knows where they'll take us next.
0:58:15 > 0:58:18If you would like to explore some of the everyday miracles of engineering and materials
0:58:18 > 0:58:22have a look at the free learning activities on the Open University website.
0:58:22 > 0:58:24Go to...
0:58:27 > 0:58:30..and follow the links to the Open University.