[Music] oh oh here this is that is a top just there ah no this is fine faster what a view I'm back um I was last year 25 years ago 25 years ha let's summon our own your left Mihama oh look at this here we are how would you like it that's okay let's do this is what I remember this is our ancient heritage laid out before our very eyes [Music] scotland's landscape has an epic and violent past hidden in these mountains and Glen's is the history of the planet I'm gonna show you how this
landscape was used by a bunch of brilliant maverick eccentric scientists to solve the greatest mysteries of the earth [Music] and following in the footsteps of these pioneers we blaze the trail where no one had been before they showed vision and determination to piece together baffling evidence and uncover the forces that shape our world Wow that's so on it's all right there if you know what to look for threatened into the Scottish landscape is the story of the entire planet [Music] [Music] toradol in the northwest Highlands of Scotland the most ancient landscape in Britain wow this
is so reward it feels like the hands in the air for centuries people have looked at this landscape and wondered how long it's been here and how it was formed [Music] it wasn't until the 1750s that the answer began to emerge from meth and superstition towards a new view of the earth based on science one man had a revolutionary new idea that changed everything changed the way we thought about the planet even but the way we thought about ourselves [Music] [Music] the man who started the Scientific Revolution grew up in Scotland's captain Eddie [Music] James
Houghton was to become the founding father of geology as a young man the hills around his home city made him curious about Harry the earth was formed pardon you still often come up here and he would have made a fantastic travelling companion in many ways it was funny he was body he was a bit rude he liked his whiskey he liked his woman and he loved debating new ideas in 1747 Hutton was a young medical graduate with an unusually broad interest in the whole natural world when he studied the origins of a landscape he found
that the accepted authority wasn't science but theology and Hutton was starting to think about the earth there really only was one geology textbook and that was this the Bible but I love a little s edition from heart this time is it gives a date for when God created the earth in the seas before Christ 4004 not just in 4004 BC but actually on Saturday the 22nd of October 4004 BC Hutten believed in God but unusually for a man of his time he wasn't committed to a literal interpretation of the Bible he believed that God had
created a world that had a system of natural laws [Music] but he then particularly dwell on these ideas instead he did what many students do he got drunk he was also getting seriously distracted by the ladies who was that that would prove his downfall it was hot ins relationship with one particular woman that seems to have led to heartache his banishment from his beloved Edinburgh Hutten had got his young lover miss Eddington pregnant this was a scandal she was rushed away to London to give birth to limit the damage to his family's reputation Haughton left
Edinburgh at the age of 26 he was forced to make a new life on a small disused family farm in southern Scotland puttan wrote that it was a Cossack country but everything conspires to break my heart [Music] but it was this remote farm that would trigger his brilliant insights about the planet oh that's a sly houses farm but what a landscape I mean it's leaking when swept and pretty soggy today I sell a notic in a place we feel as if you would devise a major new theory but there's a system but that is exactly
what Hutton did first heed the tongueless rain-drenched landscape into a profitable working farm one of the doctor jobs he constantly faced was to dig and clear drainage ditches Denise Daly Walton Farms nearby and knows what he was up against well the purpose of this stitch was to carried the water off the fields yeah but I've see what's happened is it over time or the sediment or the tops or has run off the field and it just is actually blocked this up yeah this is Goldust in terms of cultivated land wasted in these ditches [Music] every
year Hutton clear these drainage ditches and every year the rain washed the precious topsoil office fields into the ditches and carried it downstream let's bond relative Hutton's land was the start of a long journey for all that soil washed away from his fields the water flows down into large and larger streams and in rivers and of course where the water flows this time salted mud follows eventually being dumped in the sea this incessant erosion of the land seriously can sound hot because he realized that all the soil was washed away than eventually to be nothing
to grow crops and ultimately people would starve puttan looked at this erosion and realized that must happen not just in scotland but across the whole planet it appeared that God had made a world it stripped farms of a good soil eventually if this continued there would be an utterly barren landscape but to be honest puttan just didn't buy that in his heart that made no sense that God would let his people starve and in his head it made no sense that the earth would irreversibly weird away to nothing he was convinced that I had to
be a way to make new land cotton still only 34 and working in isolation had come to completely reject the conventional view of the earth [Music] he just couldn't accept that the world had been created by God at a single stroke and remained unchanged his radical thought was that God must have designed a planet that could rebuild itself the question was how could new land be formed Hutten spotted something in the landscape around this farm that gave him his first clue would have seemed castle that's all over the place if you look at this rock
face you see there's distinct layers of rock all of them subtly different hundreds of them what Hutton realized was that these bands of sediment were laid down at different times flush then from rivers and deposited one on top of the other just builds up over time year after year slowly compacted into Rock Hutton's greatest idea and I guess it seems so obvious now is that the creation of one and the destruction of lying I'm not sudden and dramatic events of Endymion biblical past but snow and imperceptible actions that are going on all the time they're
going on right now [Music] the idea that land was created from the rubble of the past was a startling new way to see the landscape and this sedimentary rock formed from layers of mud and sand laid down in rivers and seas as found everywhere from the White Cliffs of England south coast to America's grand canyon Hutton had made his first breakthrough he was now sure there was a great system driving the earth after 15 years on the farm Hutton was about to start a new chapter in his life one that would test his ideas and
push him to even greater discoveries at the age of 41 his years of exile were over he returned to the city of his youth it was the time of a Scottish enlightenment Edinburgh was the intellectual capital of the world Hudson made the most of being back all over town he debates and drinks but the greatest minds of his era [Music] you know you can see why these gatherings were ideal for Hutton his personality an excellent deep thinker and deep drinker let's open you can reveal atmosphere was perfect from two eras big idea manger even all
those bonhomie wasn't enough to paper over the cracks and Hutton's theory [Music] Hutten knew that not all the rocks he could see had been laid down in layers of sediment [Music] if the earth system continually recycled on land what other ways could rocks be formed [Music] Hutten still had a large piece of the jigsaw missing he got his inspiration from another great mind of the Scottish enlightenment his friend and arguably more famous James James Watt [Music] fellow Scotsman James Watt was an accomplished inventor famous for making steam engines more efficient who's James was harmless enough
heat that would perryland are still revolution nuttin heard a thing about machines and he was fascinated by what steam-powered contractions Hutten saw that heat gives steam-engines enormous power he began to wonder if he powered the planet maybe heat within the earth was a force that could change and renew the landscape perhaps the center of the earth contained a mighty heat engine scientists in the 1700s hadn't seen active volcanoes but they thought there were only small isolated bye puttan was a fast person to imagine that the center of the earth was a molten ball he saw
volcanoes as the vents of a giant fundus deep in there he believed that less fondness had the power to create new land land that was born if he could prove that much of the landscape had started out molten then he would have discovered another way in which the earth could continually renew itself [Music] the trouble was that if a lot of the rock started of maltin why were they all so different if they had the same origin and surely they would look the same if you're trying to define genius then I guess it would be
about making remarkable connections that no one had ever considered before but time and time again he got his ideas from farm ditches from local classrooms steam engines and perhaps his cleverest piece of lateral thinking was when he hears about an accident and a glass bottle Factory [Music] next one glass artist Siobhan Healy is going to help me recreate an incident they caught Hawkins attention at the glass factory in Edinburgh the workers accidentally left a batch of molten glass in the kiln too long we've got two piles of broken glass we'll treat one normally and use
the other to recreate the accident so this is ready just that says up to a top temperature it'll go completely molten at that temperature and that goes like liquids so this one who was in the other one yeah the slow one yeah this one's going to be substantially longer in this program because everything will be exactly the same apart from the rate of cooling the reason Hutton was so interested in the result is because he knew that molten glass would behave in the same way as molten rock Wow so that is what nine hundred degrees
feels like fantastic yeah you just want to touch it and it's the last thing my fingers would do but Oh gotcha [Music] we've cooled the two samples at different rates the results are dramatic this one here is what this is the vitrified piece of glass so this is the one that could really fast quenched real fast let's see a right fits beautifully transplant me - look at that but this complete deafness is a molten rock when it's solidified really slow so you can actually see the crystals in here look at them little angular crystals and
their texture is completely completely different [Music] crystals are formed inside the glass of rock when atoms stick together it takes a long time for clusters of atoms to grow big enough to be seen when glass cools quickly the crystals are very small and the glass is clear but when the workers left a glass to cool down over a long period large crystals were created cotton had an explanation for the many different rock types we see on the Earth's surface very slow cooling creates large crystals faster cooling creates smaller crystals like in this granite and rapid
cooling creates tiny crystals like in volcanic basalt well we've done is alter how fast the molten glass killed we've created two completely different materials from it hot and grasped that a whole variety of rocks could have started off as molten and as they solidified under different conditions their appearance and look would change this meant that he could have formed far more of the Earth's surface than previously thought and it convinced Haughton that there really was a vast internal heat engine at work Hutten had come up with two fundamental ways that land could be created sedimentary
rock could form when weather rain frost and when the Rudy the soil [Music] rivers carried the sediment to the oceans it was compressed to form new rock [Music] and the second idea that a hot core in the center of the earth could create molten rock which cooled to become land he had a clear vision of a nerve that destroyed itself in an endless cycle [Music] his idea is so so beautiful and amazingly for something that was conceived 250 years icer ago it's nearly all right it's a big coherent impressive idea and this concept of the
earth as a system continually self-renewing well fuse so warden the big question was back then was the world ready for it Hutton had to be persuaded by friends to go public with his ideas he was worried about how they would be received but in 1785 he presented his theory of the earth as a system to the Royal Society of Edinburgh imagine the scene in front of some of the greatest scientists of the age the outsider Hutton prepares to present his radical theory of the earth he's a terrible speaker that he he talks in a broad
Scots accent and he's incredibly nervous what's more he's got this this nagging feeling that he doesn't yet have enough evidence from the field to back up his theory and he knows that what he's gonna say is really controversial his ideas go against all the religious orthodoxy of the day in the event his worst fears are realized a presentation bond the gentlemen of the royal society rejected Hutton's theory out of hand was for the god-fearing Haughton he was accused of being an atheist [Music] one of the biggest upsets was about this stuff granite it's hard to
believe that this could cause even mild disagreement but it produced the most almighty stink the accepted wisdom was that granite was the first part of the earth to be created by God nothing could be more solid than the Lord's foundation stone seems solid enough that Hutton was claiming that that's hard stuff which seemed so ancient and immutable was actually the prime example of a young rock which had once been almost liquid he was saying this was born Morton to claim that granite had started out molten challenged the whole biblical view of creation two hundred and
twenty years ago less was heresy Partin needed to find some evidence from the field at the age of sixty and he should have been at home with his pipe and slippers cotton pet betrayal he headed northeast from Edinburgh into the wild he'll country of Blair Apple and pasture [Music] traveling in the 1780s was a wee bit different to what it is today it's gonna take me a couple hours to go from head in front of Blair Apple to saving sailors but but Hutton they would have taken him for three days on horseback his search for
stones would routinely give him saddle sores he once wrote Lord pity they are slits Claggett as attached to the head the hunt for stones the despite a sore ass didn't put them all [Music] on the 16th of september 1785 Putin traveled along this track in Glenn tilt [Music] he Miss Cruikshank is a game trooper on the Ethel with Steve they've got hell of an office it's one of the best offices in the world as far as I'm concerned hundred forty-seven thousand acres of office so far was coming up here in 1785 it wouldn't be much
different not much different you would be reading the same sort of Eclipse equipment as unwitting no yeah the tweeds really only the designs teams making worse camouflage than the landscape and I am not so sure knock it off with some beer with it Hutten chose to explore glen tilt because two of Scotland's great rivers meet here [Music] the river D runs over a bedrock of pink granite the reberty has a bedrock of grace and stone where the rivers met Hutson hope the granite and sandstone would also meet they contact the meeting place is right there
in the river and that's as for Hutton was going far and if he could find where the two rocks met maybe he would find evidence that granite had floored as a molten liquid into the sandstone as Hudson made his way along the river he could see the grace answered frustratingly close to never quite touching the pink granite [Music] then button arrived at these Rapids this is the bed thank us [Music] one [Music] heightened must have been just so pleased to see it you can see there the gray rock that's the layered rock and then in
front of us here you this pinky off which is there the granite and here especially over on the other side you can see it's old mix then if you you come and leg actually there look there now you see the pink rock and the gray rock told muddled end and that that's the bridge used to be a bridge over here no there's no easy way to get across well [Music] this is the rock Hutton was looking for the cracker over here look at this this is a beautiful red granite this is the gray layered rock
sandstone you can see how the granite is getting injected itself forcefully into the sandstone this is a brilliant but look this is just mud pits down here so irregular it's get like Italian a spoon or something lovely you know it's crystal clear here that the granite came from molten rock it's getting injected in all directions it's this way it's this way over there let's good up there it's across that way it's like a geological battlezone these rocks showed that a landscape had changed it had not as the Bible said remain unchanged since creation molten granite
was proof of a giant heat engine in action this discovery in Glenn tilt was a great moment for Hutton [Music] it's the Cana thriller every geologist is after it's why I too am fascinated by the rocks all around us you know the core to being a geologist accessibility to to read the landscape but it's really how to explain it to someone else you just get used to it it's kind of intuitive it's kinda like a course as well because suddenly you can't really I don't know enjoy a landscape without thinking what is that how is
it forms that sound still what I always get told off what I want holiday for a wrap for working but I'm looking at a landscape when my wife says stop geology's and it's not working and I say I'm just I'm just looking but it's true I think I Jolla just can't look at what's her own to not think how was that for [Applause] from his observations in scotland james hutton had proved much of his theory of the earth as assistant rocks were molten and cooled they were eroded and built up again [Music] puttan was not
yet satisfied he set off once more [Music] this time he was in search of clues as to how long this planet cycle of the Europe had been going on for was there are thousands of years old as the Bible said or was it much much older in 1788 Hudson headed to siccar point on the barracks at cost just a few miles from his old farm you know that's a man April normally the seas around here can be treacherous but we've got a beautiful calm sunny day which is pretty much the weather that Hutton had when
he came here by boat to friends to try and convince some of his theories of the earth what Hutton was on the lookout tom date to be the most celebrated geological find in history Hutton knew this cost well what intrigued them was the different angles of the rocks on the cliffs [Music] it's in vertical layers along part of the coast but in you that further north the angle changed completely the layers were horizontal [Music] autumns curiosity made him take a closer look [Music] it's so good to be here I mean I guess I guess it
looks like a pretty normal piece of rocky foreshore the most people but but this place is its geological ghoul I mean quite simply that it's the most important geological say on the planet you've never learned to look at it but that's a huge story - it's all here an epic tale of geological violence it takes you out to see it - to get your iron but Hutton Hutton knew instantly what it seemed nothing less than the bottom death of Paul Warren's [Music] what's remarkable is that Hutton could see all of this not on a giant
cliff but a five foot high section of rock in these horizontal and vertical layers of rock he saw one long geological cycle piled on top of another these layers of vertical gray rock started off his slot ease of sand and mud sloped off an ancient land mass and deposited in the ocean the belt up on the seabed as horizontal sheets inch by inch over millions of years but although they started off horizontal all that was about to change because the ocean started to close what Hutton couldn't have known the we've since discovered is that continents
move slowly across the globe and this is why the rock layers are vertical and don't lie flat [Music] over millions of years a continent slowly and relentlessly drifted toward Scotland the seabed crumpled pushing the layers of bedrock operate higher and higher until the decay pills and mountains and their erosion started again rivers and rain wearing them on top of the operate grills fresh sediment gradually built up and solidified into new flat layers puttan didn't know exactly what caused the formation at siccar point his brilliant insight was to realize it must involve gradual processes that happened
not in biblical time but in deep time stretching back immeasurably was rate and we now know how old these layers of rock are s gray rock is around 425 million years old and this red rock is about 345 million years old the gap between the two is 80 million years and that is ultimately Hutton's most important legacy an appreciation of deep time the timeline of a planet uh Tonetta phrase that he used he said no vestige of a beginning no prospect of an end in other words a timelessness in which small gradual changes can achieve
almost anything [Music] here at siccar point james hutton realized that one ancient rock formation could sit on top of another this process must have taken an inconceivable length of time he had no idea of how long indeed he never offered an exact same skill he could only imagine the cycle of the effort had gone on endlessly Hutton's recognition of deep time was an extraordinary breakthrough every better significant in his way his Darwin's theory of evolution or Einstein's theory of relativity as with all these great scientific advances it was difficult for people to believe ideas in
geology well in science for that matter kind like a relay race where the baton gets passed from hand to hand hopefully each turn the button gets passed along the ideas get more solid and more accepted but in the case of Hutton that baton gets seriously dropped along the way [Applause] [Music] 60 years after hotends death Britain's most respected physicist tried to calculate age of the earth [Music] a Scottish scientist so successful we could afford a luxury yacht like this it states introducing a very definitely kind of scientist William Thompson better known as Baron Kelvin of
logs he was a a colossus of world signs he's best known for the temperature skill degrees Kelvin that's him he was he was everything that honey wasn't he was deeply embedded in the academic established the forceful articulate a real Sherman Kelvin was a brilliant scientist supremely confident his own ability he rejected Hutton's theory of the earth as a system of endless change they have had to have an age even if it was far older than the Bible said Kelvin thought the hunter and his followers what unscientific his main problem was the claim that the earth
showed no vestige of a beginning in no prospect of an end and that it was in a kind of perpetual motion in other words he thought that geologists were trying to break the laws of physics it was time to smash that idea to pieces Kelvin wars are Sherman and he had a dramatic way to show the earth must be losing energy all the time my head here we have our 15 kilogram cannonball it's a lot heavier than it looks all right so what do we do so I want you to stand in position and we'll
bring the cannonball up dr. Stewart Reed from Glasgow University shows me why Kelvin was convinced that Hutton's theory of endless change in the earth was from-- and then just holding with your hands this cannonball is a pendulum car Severn spilling it on such a way I'm bring it right up to your north here we go when I let the pendulum go to swing back towards me if it hits me my head will end up like the melon okay here we go [Music] [Music] why exactly is this not training me then you know it's not possible
for the cannon ball to end up swinging higher than when you let go of it because it can't gain energy from nowhere and a natural fact that's losing energy excessive friction in the rope because of the air resistance as it's moving back and forth and so the amplitude is decreasing as it's swinging you can see that [Music] for Kelvin this demonstrated a planet just like the pendulum must lose energy over time the earth cannot be in a cycle of change that would never slow never stop you know it's a simple but effective demonstration of the
the real problem that Kelvin had with hotness theory the perverse notion that the Alpha is constantly creating destroying then recreating it suffers over and over again forever in fact the earth should be constantly losing energy just let this pendulum will eventually come to a halt eventually based on the principle that everything has to start and stop Kelvin was sure that they have had a beginning an age was about well really they never gave a precise age of the earth and Kelvin wasn't gonna let him get away with that grand claims needed to be backed up
by harmed figures and he Lord Kelvin was the man to get them he was gonna take on the most audacious and controversial question of the era Lord Kelvin was gonna calculate the age of planet Earth [Music] this is a lump of granite and we're gonna try and melt now grant it melts about 1,200 degrees Celsius several tens of kilometers down beneath our feet and we are going to try and melt it here with that with a blowtorch takeaway Carol meanwhile I'm gonna film it with a thermal infrared camera she's going to try and capture the
heat and already I can see the soaring up so 280 300 degrees Celsius Oh spray us sure Kelvin believed that earth started off Morton it's hard to look at I saw thousands about thousand degrees Celsius below the melting point of rock was Kelvin start point to calculate the age of the earth he took this as the temperature of the planet when it was created and there it has 1200 degrees Celsius Oh oh yeah [Music] this is molten rock good Kelvin argued that the planet couldn't steam molten forever we stopped a second so this is this
is no just basic physics once something's heated up we can't stay hot has to cool down from his experiment Kelvin knew how long it took small objects to cool down if he's scaled of his figures to calculate how long it would take an object the size of the planet to cool down then he would have the exact age of the earth for years Kelvin continued to tweak and refine his calculations he finally put the age of the earth between 20 and 40 million years although we now know the calculations are accurate Lord kelvins figures had
an enormous impact he provoked intense debate about the age of the earth and upset nearly everyone and versus Kelvin most things who have seen the statue he's at a traffic corner on his head and he was ridiculed too when he published his age of the earth the church hated it because it made the earth tooled fellow scientists they hated it because they are too young it just wasn't enough time for Darwin's theory of evolution to happen and ask for Hutton's heat engine well on kelvins timescale that was a non-starter Lord Kelvin had made a crucial
error [Music] his calculation was based on the idea that the earth had cooled a completely solid state but as we now know the Earth's interior didn't just cool like a lump of wall to the vault parts of it Steve Morton just as Hutton imagined but couldn't prove Calvin might have been wrong but his age of the earth stood for almost 50 years ray until 1898 when the rocks themselves revealed the truth [Music] a few years before Kelvin died there was a major breakthrough scientists discovered the source of energy deep within the planet that has helped
keep the earth molten far longer than Kelvin could have imagined radioactivity this is a pretty ordinary lump of granite from a Scottish Highlands it was clicks you're hearing a path to goes up had an offense sheet at the front of those Geiger counter and they're coming from a tiny amount of radioactive uranium contained in the rock I tend to think of radioactivity as mine me but it's actually a natural phenomena a powerful energy source of spin around this is the buff on the sources radioactivity is one of the key forces that makes hot ins theory
correct I'd love to meet Hutton and over a wescam said a warm fire tell me all the things we've discovered since he's been gone top it out less would be really active 'ti I mean the energy of radioactivity in the heat that it generated has kept parts of the planets interior and water as part of hotness heat engine which has allowed the Earth's office to be constantly recycled and rejuvenated but there's another reason why I'd love to tell them about radioactivity and that's because as well as explaining his heat engine it's been responsible for telling
us just how old the planet [Music] we can now look at the most ancient rocks on our planet and discover their true age I've returned to Turin in the Northwest Highlands [Music] I'm hoping to find the olders rocks and Breton up here I want to find out just how old Scotland is and radioactivity will give me the answer [Music] I'm heading into the backcountry with fellow geologist John Wheeler and Ian Miller when you can see it's kind of swarthy can't yes [Music] this hell is 50 times older than the era of the dinosaurs it's one
of the earliest parts of our planet [Music] wow this is spectacular isn't it look at this I mean this whole outcrop is just can a vain after being after availa that's white beautiful white wrong this rock is called Luisi and ice this is gonna rock heaven for me I mean it's just textures the shades the colors of us Louisiana nice this beautiful gorgeous and here let's just cut across it stops but what's even more fascinating more mind-blowing than just how gorgeous it is is that this rock could be part of the very far bedrock of
Britain here we go this is like the dark sailor geology cool yes much as I love this rock we need to take a sample so we can measure its age okay that's pretty good is it let's get nasty though the snow is really coming in but we've got it got the rock we wanted and it's a beautiful piece of Louisiana nice and apart from just looking gorgeous this is a question am i holding in my hand a fragment one of the oldest bits of Britain I'm going to find out we've got to get it to
the love let's get off this boat [Music] so this is it this is my rock it is the blind nose to find a hole just piece of Scotland [Music] the key thing and we have to do first off is to smash the hell out of this rock we do this in this machine here the ground up rock contains a radioactive crystals and so that's what I rocky started like that's what is known and somewhere in here now we're going to examine those crucial crystals using an electron microscope so it's creating a vacuum that's treating a
backing and say your sample that you collected we've managed to extract a large number of zircon crystals the zircon crystals are time capsules they're full of radioactive uranium which breaks down into lead at a regular rate you can actually see the shape of the crystal was quite a nice that's really beautiful the proportion of uranium and lead left in the zircons will reveal the age of the rock [Music] the machines spit so an extraordinary bunch of enough morsel lots of numbers lots of my gosh lots of lots of yeah many many numbers there ranging from
of about 2000 2500 up to a little bit over 3,000 million years old these ages are just unfeasibly old I mean 3000 129 million years this is astonishingly amazing you know the fact that it's between two point six and three billion years old is truly remarkable I mean this thing has been around for two thoughts of the age of the planet the earth is 4.6 billion years old and the notion that a lump of Scotland is almost 3000 million years old well what would heighten emitted her [Music] the rocks of toradol were created and the
very first continents on earth were being born the ancient landscape of Scotland is a witness to billions of years of geological change it was one pioneer who made this vision of a landscape possible james hutton made one of the greatest leaps and human thought when he looked at a landscape he saw what no one else had seen before he was a foster grasp the true vast age of the earth and it was that discovery more than any other that's allowed us to piece together the complex story of the life of our planet [Music] next time
I'll follow in the footsteps of the Gong ho geologist he uncovered Scotland's volcanic past and the unsung hero you can actually see it starting to go up there we solved the mystery of what makes continents move across the surface of the globe [Music] [Music] [Music] you
