Speaker 1: Hey, welcome to Invention. My name is Robert lamp and
Speaker 1: I'm Joe McCormick. Today we're talking about an invention that
Speaker 1: it's certainly been in the news a bit recently. Um,
Speaker 1: we're talking about walls. Okay, Now, we're not a political show,
Speaker 1: but some of the statements on the nature of walls,
Speaker 1: the purpose of walls, the historical and modern effectiveness of
Speaker 1: walls are unavoidable here and and hopefully, uh, this is
Speaker 1: all gonna be useful by the time we finished this episode.
Speaker 1: You're gonna have, you know, a deeper context regarding the
Speaker 1: nature of walls and what a wall is, uh, the
Speaker 1: next time you were subjected to the news. Now, I
Speaker 1: noticed we've been on a tear recently of extremely ancient inventions.
Speaker 1: I think we did roads and then the wheel, and
Speaker 1: now we're on walls. It's almost like we're just going
Speaker 1: further and further back in time. And so I'm sure
Speaker 1: we'll get back to some some more recent or high
Speaker 1: tech gadgets soon, but definite biographies involved to the thing
Speaker 1: about the more modern inventions. But I do really like
Speaker 1: doing this kind of thing we're doing by like looking
Speaker 1: at the most basic technologies that exist like the wheel
Speaker 1: and the wall, because there's so many interesting ways to
Speaker 1: look at their you know, they're they're multi millennial legacy
Speaker 1: and impact on human culture and history. Now, i'd say,
Speaker 1: in addressing the wall, we are going to be talking
Speaker 1: a little bit about a few interesting tidbits of of
Speaker 1: physical construction. But this isn't gonna be so much an
Speaker 1: episode about like wall materials and all that. You obviously
Speaker 1: that is a very rich subject on its own, but
Speaker 1: I think we're gonna be thinking more about the role
Speaker 1: that walls play in geopolitical history. Yeah, yeah, because certainly
Speaker 1: the history of walls is kind of the history of
Speaker 1: construction and engineering in a broader sense. And we have
Speaker 1: to be clear here too about how we're we're looking
Speaker 1: at walls, because there's there's a very good chance that
Speaker 1: if you're listening to the show right now, you are
Speaker 1: either con hanged within walls or perhaps adjacent to a wall.
Speaker 1: Even if you're just driving down the road. Um, you know,
Speaker 1: you you can probably see some walls right now. Maybe
Speaker 1: you're forming part of a human wall, maybe you're walking
Speaker 1: on top of a mile high wall. Yeah, all these
Speaker 1: are possible, and any of us can build a crude
Speaker 1: wall out of sticks or rocks, etcetera, with only the
Speaker 1: most basic engineering skills. And in a basic sense, I mean,
Speaker 1: this is something that exists in nature. I mean, why
Speaker 1: do we have the idea that certain types of animals
Speaker 1: and maybe some of our ancestors sought out caves for shelter.
Speaker 1: It's because they've got walls and a roof, right, These
Speaker 1: like they limit the the they limit your exposure to
Speaker 1: the weather through a roof especially, but they also limit
Speaker 1: the number of access points through which other animals, say,
Speaker 1: could reach you exactly. So we're largely going to talk
Speaker 1: about walls as barriers around cities and then more to
Speaker 1: the point, as freestanding divisions. And in this we really
Speaker 1: need to think of them. I think I I believe
Speaker 1: a sort of of geoengineering project. Uh. You know, it's
Speaker 1: easier to see this in walls that are created using
Speaker 1: elements from the natural surroundings. Say a wooden fence or
Speaker 1: a beautiful moss covered stone wall in Ireland. You know,
Speaker 1: something that would you really looks good on a calendar,
Speaker 1: But it's less obvious when you behold something like say
Speaker 1: the Great Wall of China or the Peace Lines or
Speaker 1: Peace Walls of Ireland or the Berlin Wall something of
Speaker 1: this nature. But a wall essentially seeks to do what
Speaker 1: the environment does naturally. It's a sheer, vertical rise in
Speaker 1: elevation manufactured to impose a particular cultural, political, or personal domain.
Speaker 1: You know. Well, you can just imagine somebody perhaps you know,
Speaker 1: a far side cartoon caveman, thinking, you know, I wish
Speaker 1: my property were on top of a mountain to keep
Speaker 1: my enemies away. Well, boom, here's how a wall works.
Speaker 1: Now you have a mountain or something that functions like
Speaker 1: a mountain, creating a vertical obstacle between your and somebody
Speaker 1: else's stuff. But there are multiple different ways to think
Speaker 1: about the idea of a wall as protection, and this
Speaker 1: will come out when we talk about the more macroscopic
Speaker 1: wall projects throughout history as we go on. Because there's
Speaker 1: one type of being protected in walls that's literally like
Speaker 1: I need a barrier to like keep people from coming
Speaker 1: in and stealing all my things, or to keep you,
Speaker 1: I don't know, a lion from coming and grabbing me
Speaker 1: while I'm asleep. But on the other hand, you've also
Speaker 1: got the type of protection that is the psychological sense
Speaker 1: of privacy, right that a wall is a barrier that
Speaker 1: people can't see through that allows you to feel like
Speaker 1: you are not constantly being say, observed by your neighbors. Yeah,
Speaker 1: like like a privacy fence in one's backyard. We tend
Speaker 1: not to think of them as walls of wood. I
Speaker 1: will erect walls of wood between me and my so
Speaker 1: called neighbors. No, it's privacy fence, you know, just in
Speaker 1: case you don't want to, you know, walk around shirtless
Speaker 1: in your backyard, which you should. It's your backyard. Do
Speaker 1: what you want or you don't want people steal in
Speaker 1: your genius invention that you're building back there exactly so,
Speaker 1: its stated earlier prehistoric times, before walls, they required humans
Speaker 1: to depend on naturally occurring barriers. You know. Uh, where
Speaker 1: can one position themselves so that they're best protected from
Speaker 1: the elements, predators, enemies, etcetera. And these could these could
Speaker 1: be any number of things, right in addition to vertical
Speaker 1: changes in elevation, Uh that could be uh, rivers, pond streams,
Speaker 1: swampy areas, etcetera. And of course early humans and Neanderthals
Speaker 1: were nomadic. Uh. There was nothing to be gained in
Speaker 1: the creation of heavy duty barriers because you were always
Speaker 1: or at least cyclically on the move. You had no cities,
Speaker 1: You had no domesticated herds or crop fields that needed
Speaker 1: to be cut off from other aspects of the natural world. Um,
Speaker 1: there were also precious few of you to begin with.
Speaker 1: But of course all that changed. Cities gave rise to walls,
Speaker 1: and city states and empires gave rise to even more.
Speaker 1: Wall is a division between the ever expanding, ever advancing
Speaker 1: tribes of humanity. Right, you're correct to point out that
Speaker 1: the wall revolution. I mean, we we don't know when
Speaker 1: the first wall was created, but it would have to
Speaker 1: be linked to the idea I would think of of
Speaker 1: a sedentary lifestyle, like as people stop moving around and
Speaker 1: settle in places, to live in one place and stay there.
Speaker 1: And we do, in fact see some of the earliest
Speaker 1: archaeological evidence of walls in the most ancient of the
Speaker 1: sort of city states of the ancient Near East, for example,
Speaker 1: like there are ten thousand year old walls that have
Speaker 1: been discovered in the city of Jericho. Now, when it
Speaker 1: comes to what we were talking about, the more sort
Speaker 1: of freestanding barrier walls that might mark the border of
Speaker 1: a territory or uh, you know, or something more like
Speaker 1: the Great Wall of China, which will discuss it more
Speaker 1: length as we go on. Among the world's earliest known
Speaker 1: defensive barrier walls, or the walls of ancient Mesopotamia specifically,
Speaker 1: uh some walls constructed in the twenty one century BC
Speaker 1: by the sumer Arian rulers Shulgi and shu Sin. And
Speaker 1: these were constructed in the region that is modern day
Speaker 1: Iraq in order to defend the ancient civilization of Summer
Speaker 1: against attacks of nomadic people's known as the Amorites. And
Speaker 1: so this wall was also known as the Wall of
Speaker 1: the Land or the Amorite Wall. We think that it
Speaker 1: probably reached more than a hundred miles in length, stretching
Speaker 1: between the twin rivers bound that bound Mesopotamia as the
Speaker 1: Tigress and the Euphrates. And while this wall was probably
Speaker 1: meant to protect Sumerian cities, it was not, as we said,
Speaker 1: a city wall. It's kind of a border wall. I
Speaker 1: found one piece of ancient Sumerian poetry in fact, that
Speaker 1: seems to be referring to the wall, or at least
Speaker 1: to a fictional analog of it, and it's translated and
Speaker 1: explained in a book called Reading Sumerian Poetry by the
Speaker 1: scholar Jeremy Black. And in this ancient Sumerian poem, you've
Speaker 1: got the legendary Sumerian king in Merkar, and he's out
Speaker 1: with his army at war, laying siege to a foreign city,
Speaker 1: and he gets all demoralized, feeling he's not having a
Speaker 1: good time, and he arranges to send a message back
Speaker 1: to the mighty goddess in Ana, one of our favorites
Speaker 1: from stuff to blow your mind. She you know, she
Speaker 1: shrieks power through the rebel lands, and he's out at
Speaker 1: war while Innana is residing back in her temple in
Speaker 1: the city of Unugs, a Sumerian city also known as Uruk,
Speaker 1: and so in Makar's message implies that you know, once
Speaker 1: within on his help, his reign had been really great.
Speaker 1: It was great and glorious, and he built powerful, impressive structures.
Speaker 1: But now things have gone bad, and he feels abandoned
Speaker 1: by the goddess and Anna while she sits at home
Speaker 1: refusing to come to his aid to help him accomplish
Speaker 1: glorious things again. And this is Black's translation of this
Speaker 1: passage from the poem The Wall of Unug extended out
Speaker 1: over the desert like a bird net. But here and now,
Speaker 1: my attractiveness to her has ended. My army hangs on
Speaker 1: me as a cow hangs on its calf, like a
Speaker 1: son who hating his mother, leaves his city. My princely
Speaker 1: sister Holy Anna has run away from me to brick
Speaker 1: built Coolaba. So that first line there, that line the
Speaker 1: wall of Unug extended out over the desert like a
Speaker 1: bird net. I love that image, and Black writes that
Speaker 1: this metaphor actually does refer to a real technology, quote,
Speaker 1: a long net of a type used for snaring low
Speaker 1: flying birds, extending out across the open country. Though I
Speaker 1: do find it interesting that here the metaphor for the
Speaker 1: wall is an animal trap, not a defensive structure. Yeah,
Speaker 1: something to snare, and uh, I guess it makes it
Speaker 1: feels maybe metaphorically more imposing, like this is a thing
Speaker 1: in which upon which you die, as opposed to this
Speaker 1: is a thing that stands between the two of us. Yeah.
Speaker 1: Though it's funny because the wall, as invoked in the
Speaker 1: poem is not so much invoked as a literal defensive
Speaker 1: measure that is effective at its purpose. Instead, it's invoked
Speaker 1: as an emblem of the city of Unug's former power
Speaker 1: and prosperity. This is a fictional account being told in
Speaker 1: this poem. Uh the historical context when the poem was
Speaker 1: being read probably meant to call to mind more like
Speaker 1: the more recent and real construction of that defensive wall
Speaker 1: I mentioned earlier, the walls built by the king's Shulgi
Speaker 1: and shu Sin, known as we mentioned earlier, as the
Speaker 1: Wall of the land, and also as the keeper at
Speaker 1: bay of the nomads. That's a good title, nice and formal,
Speaker 1: and that that's that's kind of a recurring theme in
Speaker 1: these older walls. It's a way of keeping out the
Speaker 1: nomadic people's. But no matter how much the author of
Speaker 1: this poem thought of this wall as this great building accomplishment,
Speaker 1: you know that symbolizes the glory and splendor of Invercar's
Speaker 1: former rule, Ultimately the real wall failed to protect Summer
Speaker 1: and the Sumerian civilization. It fell to attacks from multiple enemies,
Speaker 1: the Amorrits and the Elamites. The wall didn't work all right.
Speaker 1: On that note, let's take a quick break, and when
Speaker 1: we come back, we're gonna talk about the Great Wall
Speaker 1: of China. Okay, we're back now on the subject of
Speaker 1: city walls, kind of the the initial precursor to these
Speaker 1: dominion walls. Um To really drive home the importance of
Speaker 1: walls here, the interconnectedness between walls and cities. Uh consider
Speaker 1: that the Mandarin Chinese word for wall, ching is also
Speaker 1: the word for city, so chang shih more specifically means town,
Speaker 1: and the Great Wall of China, which we're about to
Speaker 1: get into here is uh chiang Ching. And they the
Speaker 1: Chinese also had a god of walls and moats. Let's
Speaker 1: not forget that moats are very much in the same
Speaker 1: geoengineering vein here right along with things like trenches and ditches.
Speaker 1: If a wall is a fake mountain, the moat is
Speaker 1: a fake river. Exactly to make a kind of observation. Sorry,
Speaker 1: So the name of this god was shing Wong, and
Speaker 1: it's it's a bit complex, but the god, this city god,
Speaker 1: is sort of a representative spirit and protective deity that
Speaker 1: looks after the city. But it also encompasses deified to
Speaker 1: see city leaders that protect the city via the spirit realm,
Speaker 1: and they also represent the residents of the city and
Speaker 1: dealings with the King of the dead, so of the
Speaker 1: King of the dead comes for residents of the city.
Speaker 1: He's like the immediate contact that sort of thing. Is
Speaker 1: there a reason for that? You know why him? Well,
Speaker 1: it gets kind of it's kind of a complicated history there,
Speaker 1: because with several phases to it. On one hand, there's
Speaker 1: this idea of like veneration of an individual that was
Speaker 1: important to the people UH during their life, and then
Speaker 1: it makes sense that their their spirit would sort of
Speaker 1: hang around and be important after death, part of the
Speaker 1: whole veneration of ancestors. But then also this ends up
Speaker 1: being emphasized at different points by by by China, by
Speaker 1: Chinese rule as well. Now along these lines, in Chinese traditions,
Speaker 1: there's more to a wall than mere physical construction. A
Speaker 1: wall is also kind of a spell that keeps out
Speaker 1: evil forces in addition to say, you know, invaders, physical invaders, nomads,
Speaker 1: northern barbarians. So yeah, let's talk a little bit about
Speaker 1: the Great Wall. So the original wall was built more
Speaker 1: than two thousand years ago, UH during the the Chin
Speaker 1: dynasty UH led by Emperor Chin Xi Wong, who stuffed
Speaker 1: all your mind. Listeners may remember, we've we devoted an
Speaker 1: entire episode UH to to his life and his tomb,
Speaker 1: his undisturbed tomb, which has been legendarily appointed with many
Speaker 1: fine booby traps which we we very much hope are real,
Speaker 1: but we don't know. Yeah, possibly rivers of lead, I believe,
Speaker 1: or of mercury. It was mercury, yes, So anyway, he was,
Speaker 1: he was an imposing figure. He united the seven warring kingdoms,
Speaker 1: and uh, there were these separate walls built by independent
Speaker 1: kingdoms that he then had linked together to protect against
Speaker 1: those marauders, those northern barbarians. And the oldest parts of
Speaker 1: this wall system seemed to date back to the seventh
Speaker 1: century b C. Now, hundreds of thousands of workers uh
Speaker 1: spent ten years uh working on this. We're talking prisoners,
Speaker 1: political enemies, peasants, uh, and then various dynasties would go
Speaker 1: on to work on it some more. But it wasn't
Speaker 1: until the rise of the Ming dynasty in thirteen sixty
Speaker 1: eight that the Great Wall of China as we know
Speaker 1: it today really was brought to full fruition. So how
Speaker 1: great is this wall? Well, it's reported length is widely
Speaker 1: disputed and ranges anywhere from fifteen hundred miles or two thousand,
Speaker 1: four hundred fourteen kilometers to four thousand, one hundred sixty
Speaker 1: three miles or sixty seven hundred kilometers. Uh. You know
Speaker 1: essentially the idea here as it can go from the
Speaker 1: construction from the Gobi Desert to the Yellow Sea. But
Speaker 1: it came about in installments, right, Yeah, So it wasn't
Speaker 1: just one day a great import decided to build the wall.
Speaker 1: They were like, look, we have all these these existing walls,
Speaker 1: let's stitch these together. And also let's reinforce areas. So
Speaker 1: there were areas that they didn't know you only add
Speaker 1: length to it. They added double and triple walls in
Speaker 1: some places to reinforce what was already there. Um and
Speaker 1: and that's why in some areas you have a wall
Speaker 1: that is thick enough to drive a car on top
Speaker 1: if if if you wanted to and had permission to
Speaker 1: do so. Obviously, how do you get permission for that, Well,
Speaker 1: there's a there's a whole system you have to go through. Joe,
Speaker 1: I bet they're stingy with those permissions. I imagine they are. Now.
Speaker 1: I think most people know this anti factoid at this point.
Speaker 1: But as we've discussed on stuff to blow your mind
Speaker 1: before that that old trope that you can see the
Speaker 1: Great Wall of China from space. Not true. I'm not true.
Speaker 1: I mean it's still very impressive, don't be wrong, But
Speaker 1: but no, idea, it is not visible from space. There
Speaker 1: are plenty of things that humans have made that are
Speaker 1: visible from space, but the Great Wall of China is
Speaker 1: not really one of them. Now, I was looking at
Speaker 1: one interesting study about ancient Chinese construction methods, specifically with
Speaker 1: with walls in ancient China, and this is that many
Speaker 1: of them were built with a powerful mortaring material that
Speaker 1: was made with the secret ingredient of sticky rice. Have
Speaker 1: you read about this? No, I'm not familiar with this one.
Speaker 1: So I first came across this because our friend and
Speaker 1: colleagues got Benjamin linked us to a piece on it.
Speaker 1: But I was I was reading about this a little deeper,
Speaker 1: and so basically, here's the deal. So you've got mortar, right.
Speaker 1: Mortar it's the building material that you used to help
Speaker 1: bond stones or bricks or other hard elements together into
Speaker 1: a structure. And mortar goes way back. You use a
Speaker 1: paste like this, even it was used in the Pyramids. Uh.
Speaker 1: Now a common mortar used throughout history is lime or
Speaker 1: slake clime. Uh. Then slake clime is limestone that has
Speaker 1: been heated to a high temperature and hydrated with water.
Speaker 1: But about fifteen hundred years ago, it seems that construction
Speaker 1: engineers in a China discovered a way to make this
Speaker 1: powerful and resilient composite inorganic organic mortar by mixing slaked
Speaker 1: lime with soup or porridge based on sticky rice, and
Speaker 1: together the slaked lime and the sticky rice soup make
Speaker 1: a mortar that is much stronger than other known technologies.
Speaker 1: So there was a study about this in two thousand
Speaker 1: and ten by fu Weei, Yang, Bingjian Jong, and Chinglen
Speaker 1: Ma and it was called study of sticky rice lime
Speaker 1: mortar technology for the Restoration of Historical masonry construction in
Speaker 1: Accounts of Chemical Research in two thous and the research
Speaker 1: identified the most important ingredient as a polysaccharide known as
Speaker 1: a melo pecton, which is an element of starch, which
Speaker 1: is of course found in rice, but is also in
Speaker 1: all kinds of starchy foods like potatoes and corn and stuff.
Speaker 1: And the author's right that when they tested the sticky
Speaker 1: rice based mortar against more traditional lime only mortars, the
Speaker 1: sticky rice based one quote has more stable physical properties,
Speaker 1: has greater mechanical strength, and is more compatible, which makes
Speaker 1: it a suitable restoration order for ancient masonry. Um so
Speaker 1: they suggest we could even use this today if we're
Speaker 1: like restoring ancient buildings that need their bricks stuck together better. Interesting.
Speaker 1: I mean, I hate to waste good, good sticky rice, yeah,
Speaker 1: in in building a structure. But but it sounds convincing. Well,
Speaker 1: this wouldn't be the only case actually where food crop
Speaker 1: based starches have proven useful as a non food adhesive. Apparently,
Speaker 1: potato starch makes a popular kind of wallpaper paste. Have
Speaker 1: you ever read about this? I looked it up there,
Speaker 1: like recipes online for for making your own wallpaper paste outtatos. Interesting.
Speaker 1: I mean, I guess now it makes sense here as well,
Speaker 1: because I have learned from the Fallout games that if
Speaker 1: you have vegetable starch, you can turn that into adhesive
Speaker 1: at a workstation. Really so so so it lines out
Speaker 1: up with the Fallout technology trees. I never knew those
Speaker 1: games are so educational they but that is a great
Speaker 1: kind of ingenuity. Like you take the things you say, well,
Speaker 1: we eat this for breakfast, but what if we also
Speaker 1: used it to hold bricks together. Yeah, yeah, like it's
Speaker 1: sticky in my mouth. I bet we could. We could
Speaker 1: use this if we had to in constructing a wall. Now,
Speaker 1: following the Manchu invasion of the seventeen hundreds, the Great
Speaker 1: Wall of China was largely abandoned as a military priority.
Speaker 1: What's more, maus a tongue um, he ended up encouraging
Speaker 1: the Chinese people to use bricks in other parts of
Speaker 1: the wall or building projects. Uh So a large portion
Speaker 1: of the wall was essentially vanished during all that as well.
Speaker 1: But ultimately the big question here that that one might
Speaker 1: ask is did the Great Wall of China work right?
Speaker 1: Did it like repel invaders from the north right? And
Speaker 1: there's a there's a you know, there's a lot of
Speaker 1: fascinating history and discussion on this topic. I will point
Speaker 1: out that there's an excellent article in National Geographic called
Speaker 1: The Great Wall of China's Long Legacy by Bore Pellaguero
Speaker 1: Alcade and uh it's I'll try to link to it
Speaker 1: on the landing page for this episode, but it's well
Speaker 1: worth checking out. It really goes goes in deep but
Speaker 1: but in a very readable, digestible manner. So the most
Speaker 1: specific threat that the wall was dealing with were again
Speaker 1: the northern barbarians, the neumatic people's uh you know from
Speaker 1: from Mongolia and and so forth, And it was never
Speaker 1: the only protection in place. It's always important to note
Speaker 1: with walls, like it's easy to just have that stark
Speaker 1: image of the wall in your mind. Is this this
Speaker 1: tremendous human geoengineering project. I have made a mountain and
Speaker 1: nunshell cross. But generally there's other stuff going on with
Speaker 1: a wall, be it just a military or certainly there was.
Speaker 1: The Chinese did have military forces, but there were also
Speaker 1: economic policies under various rulers to keep the northern people
Speaker 1: in check. Economic policies what could that amount to ransom?
Speaker 1: Basic essentially yes, like economic stimulus et cetera, making payments
Speaker 1: and saying hey, here's here, you don't want to come
Speaker 1: and invade us, just here take some some of this.
Speaker 1: But this only worked for so long, and then the
Speaker 1: Genghis Khan led the Mongol invasion in twelve eleven captured
Speaker 1: the capital, and in twelve fifteen his son Kubla Khan
Speaker 1: conquered all of China and founded UH, the Yon dynasty
Speaker 1: and UH ultimately the con rule lasted less than a century,
Speaker 1: and following a peasant uprising, the Ming dynasty again uh
Speaker 1: took power in thirteen sixty eight. And again this is
Speaker 1: where the wall as we know it really came together.
Speaker 1: Um according to that National Geographic article. You know, they
Speaker 1: were employing economic means as well um foreign aid to
Speaker 1: keep the barbarians at bay. But this didn't work perfectly.
Speaker 1: Border attacks continued until one when trading posts were built
Speaker 1: on the board, which apparently helped ease tensions. But again
Speaker 1: this is kind of a uh An economic solution, UH
Speaker 1: that is working alongside all of this wall building that's
Speaker 1: going on at the time. Now, this ongoing Mongol conflict
Speaker 1: weakened the Ming dynasty and it fell to another peasant uprising.
Speaker 1: And then under the Ching dynasty, China's northern border expanded
Speaker 1: well beyond the wall, making it even more unnecessary. But
Speaker 1: though it remained a symbol of cultural pride, but a
Speaker 1: relic of the past at the same time. So I
Speaker 1: feel like the Great Wall of China side. Besides being
Speaker 1: one of the most iconic examples of a you know,
Speaker 1: a free standing dominion wall in human history, it also
Speaker 1: has some some potential lessons about the limitations of walls,
Speaker 1: the life cycle of walls, um, you know, and just
Speaker 1: again the nature of walls not working in isolation because
Speaker 1: obviously any wall, they're in their numerous ways to get
Speaker 1: under it, to go over it, to go through it, etcetera. Uh,
Speaker 1: there have to be other things in place with it. Absolutely,
Speaker 1: But then you know, another interesting thing to think about
Speaker 1: when we consider historical walls, barrier walls of this type
Speaker 1: is to think about, um, do we always just accept
Speaker 1: the assumed stated purpose that that were given for why
Speaker 1: they were built. I mean, you can assume that probably
Speaker 1: it was a major reason that the Great Wall of
Speaker 1: China was built that you know, you want, they wanted
Speaker 1: to keep out invaders from the north, to prevent raids
Speaker 1: and attacks and that kind of thing. But there can
Speaker 1: be other things to consider as well. And I wannah,
Speaker 1: I want to bring up the idea of Hadrian's Wall
Speaker 1: to take another look at this. All right, well, let's
Speaker 1: take a quick break first and then we'll come right
Speaker 1: back with Hadrian's Wall. All right, we're back. So another
Speaker 1: famous defensive barrier wall in history is known as Hadrian's Wall.
Speaker 1: Around the year one twenty two, see the Roman emperor Hadrian,
Speaker 1: who ruled from one seventeen to one thirty eight, commissioned
Speaker 1: the construction of a giant wall from shore to shore
Speaker 1: in what is today Northern England, supposedly to protect the
Speaker 1: inhabitants of Roman Britain from tribes in Northern Britain, which
Speaker 1: is present day Scotland, such as the Picks. And this
Speaker 1: was a big project, I mean we are talking about
Speaker 1: going from from sea to see. It was a military
Speaker 1: construction project, taking about fifteen thousand soldiers to build. And
Speaker 1: Hadrian's Wall remains today the longest stone wall in Europe,
Speaker 1: stretching about a hundred and seventeen kilometers or seventy three miles,
Speaker 1: and the way it goes from shore to shore, it's
Speaker 1: not hard to see this is the historical inspiration for
Speaker 1: the Wall in Game of Thrones. Uh. In fact, I
Speaker 1: think that's pretty explicit, right that that that Martin, George R.
Speaker 1: Martin has has mentioned this as the inspiration. Yeah, he's
Speaker 1: he's he's come out and said the White Walkers are Scots,
Speaker 1: just straight up. Now he hasn't said that, but but yeah,
Speaker 1: it's like clearly, the the wester roast Um Wall, the Ice,
Speaker 1: the Wall of ice goes from sea to sea, just
Speaker 1: like Adrian's Now, unlike in the fantasy books, this is
Speaker 1: not a giant, you know, thousand foot tall wall made
Speaker 1: of ice. This wall was about fifteen feet tall or
Speaker 1: about four point five meters we actually, I think it
Speaker 1: was different heights at different areas, but generally about fifteen
Speaker 1: feet tall. And it took about six years to complete building.
Speaker 1: And it remained in some phase of use more or
Speaker 1: less until the end of Roman power in Britain, which
Speaker 1: was in the early fifth century. Uh. Though some parts
Speaker 1: of the wall remain in place, a lot of it
Speaker 1: has fallen into disrepair, and much like the Great Wall
Speaker 1: of China, has been plundered over the centuries for building materials. Yeah,
Speaker 1: because here you have just a wonderful collection of bricks
Speaker 1: or whatnot. Uh, it would it would just be irresistible
Speaker 1: to loot it a little bit. I mean we see
Speaker 1: that with other constructions throughout history. I mean just think
Speaker 1: about the example of the Rosetta stone, Uh, the the
Speaker 1: tablet that it was so instructive in understanding ancient Egyptian
Speaker 1: It was found not in its original location, but it
Speaker 1: reused in building another structure. Well, it's like palam sests,
Speaker 1: you know, reusing priceless literary artifacts of the ancient world
Speaker 1: to write other stuff on. Yeah, or that you don't
Speaker 1: like what's on the canvas, paint over it. I'm hoping
Speaker 1: that the end of Game of Thrones involves a lot
Speaker 1: of like steady looting of the ice wall for use
Speaker 1: in cocktails among the northern people. I thought you were
Speaker 1: gonna say for use and igloes. Well it was too
Speaker 1: I guess that would be more practical iglues and cocktails.
Speaker 1: So there there are some really differing historical interpretations about
Speaker 1: why Hadrian's Wall was actually built, like what purpose it
Speaker 1: served and whether it was effective and to what extent.
Speaker 1: In the words of Hadrian's biographer, the purpose of the
Speaker 1: wall was to quote separate the Romans from the barbarians,
Speaker 1: because that's pretty clear. So they've got a caledone me
Speaker 1: up above the wall and they think, oh, those are
Speaker 1: the barbarians. We got to cut ourselves off from them.
Speaker 1: But modern historians differ about how effective it would be,
Speaker 1: what it was really meant for, and all that. As
Speaker 1: a true military defensive wall, I think it's clear that
Speaker 1: it would serve some purpose, but that it would not
Speaker 1: be a totally effective barrier, and in fact it wasn't there.
Speaker 1: There were times when it failed to stop, say, picked
Speaker 1: raids in an area, even after the wall had been constructed.
Speaker 1: But it would serve some kind of military purpose, like
Speaker 1: the wall would help help you hold a border area
Speaker 1: from advancing raiding parties or armies with fewer numbers of
Speaker 1: troops that would be required without walls, so you wouldn't
Speaker 1: have to like send out a military response to absolutely
Speaker 1: every uh, you know, teeny raid that's going on, like
Speaker 1: every time somebody throws a rock at your border. Right,
Speaker 1: But at the same time, a lot of modern historians
Speaker 1: seemed to doubt the idea that the wall was purely
Speaker 1: or even primarily for like military defensive purposes, and they
Speaker 1: kind of de emphasized this as the motivation for building
Speaker 1: it or as the actual function of it once it
Speaker 1: was built. And if these doubters are correct, what could
Speaker 1: the purpose of the wall be. One common explanation I
Speaker 1: came across is that the wall is not a defensive
Speaker 1: structure as much as a way of controlling traffic, essentially
Speaker 1: to route travelers and traders through military controlled gates where taxes, customs,
Speaker 1: and tolls could be extracted, which would make it essentially
Speaker 1: a fundraising operation. And then well, well no really, and
Speaker 1: this is this is I think a very plausible way
Speaker 1: of explaining things. Uh. This hypothesis is often supported by
Speaker 1: reference to the placement and design of the many big
Speaker 1: gates of the wall and the archaeological record of trade
Speaker 1: and goods on either side. It looks like there was
Speaker 1: a lot of economic commerce going back and forth across
Speaker 1: the wall, and the Empire would have wanted a way
Speaker 1: to make money off of that. Another explanation I've come
Speaker 1: across is that it was essentially a giant make work project.
Speaker 1: So like, imagine you've got a big army, your Hadrian,
Speaker 1: and you've sent an army north to try to conquer
Speaker 1: all of Great Britain or what was what is now
Speaker 1: Great Britain, and they essentially failed. They didn't conquer all
Speaker 1: of Caledonia, they couldn't get up into the highlands. Um,
Speaker 1: so you've got an army after a failed campaign, hanging
Speaker 1: around down in what is now England, in Roman Britain.
Speaker 1: And it's generally, I think a bad idea in ancient
Speaker 1: Rome to have thousands of military men sitting around board
Speaker 1: at an imperial frontier. Uh So, perhaps one explanation is
Speaker 1: that it was just sort of a boondoggle to keep
Speaker 1: the legionaries of the Roman of Roman Britain busy, though
Speaker 1: this last hypothesis is considered unlikely by some. For example,
Speaker 1: the author I'm about to site. So there's an article
Speaker 1: about Hadrian's Wall and a smaller, more northern situated wall
Speaker 1: known as the Antonine Wall in the edition of Current
Speaker 1: Archaeology by the author and Current Archaeology Editor Matthew Simons,
Speaker 1: who has recently written a book for Cambridge University Press
Speaker 1: about Roman efforts to protect the borders and frontiers of
Speaker 1: their empire. And Simon's points out a few things about
Speaker 1: Hadrian's Wall. One of them is that we might be
Speaker 1: thinking about the function of a wall in a way
Speaker 1: that is colored by modern understandings of nation states and borders. Usually,
Speaker 1: though not always, but usually today, if somebody puts up
Speaker 1: a barrier wall around a territory, they're trying to control
Speaker 1: an existing, agreed upon border. So the idea being like
Speaker 1: one nation has drawn a line in the sand and said, oh,
Speaker 1: if this is the border, and then and then there's
Speaker 1: a sense, oh, maybe you're not respecting that border. Now
Speaker 1: I'm gonna build a wall on that line in the sand.
Speaker 1: So now it's it's it's even it's even more clear,
Speaker 1: and you can't get over exactly. But maybe in Roman
Speaker 1: times the purpose of a border wall is not so
Speaker 1: much to reinforce a clear and agreed upon existing border,
Speaker 1: but to create one right to sort of mark off
Speaker 1: territory as clearly yours and Simon's writes that, you know,
Speaker 1: the Romans controlled the southern part of Great Britain, but
Speaker 1: they could not fully conquer the northern part that's now
Speaker 1: Scotland due to strain on military resources. So in order
Speaker 1: to cement control and establish a border, maybe they built
Speaker 1: a wall essentially as a way of saying here we are,
Speaker 1: which would have been at least as important as a
Speaker 1: symbol as it was as a practical barrier to like
Speaker 1: prevent incursions. This brings me back to the idea of
Speaker 1: of walls and Chinese traditions as being not only physical structures,
Speaker 1: but a kind of spell. Yes, you know, because because
Speaker 1: a symbol is a powerful thing, it it communicates an idea,
Speaker 1: and a wall of course has two sides. It can
Speaker 1: communicate one message in one direction, and another in the
Speaker 1: other direction, one for those beyond the wall, and another
Speaker 1: message for those within exactly. And so I was reading
Speaker 1: another article where speaking to n PR, there is a
Speaker 1: woman named Linda Tuttiet who was the chief executive of
Speaker 1: the Hadrian's Wall Trust, and she says that there's quote
Speaker 1: quite strong evidence that the wall was painted white in
Speaker 1: Roman times, so as you can imagine, that would have
Speaker 1: been visible from miles and miles and miles away. So
Speaker 1: it's it's there in this idea, it's there is like
Speaker 1: a symbol, a beacon, a thing for people to see
Speaker 1: and be reminded that this is Rome, right, because they,
Speaker 1: especially to the north, they do not have a map.
Speaker 1: I'm guessing they can't just you know, pull up a
Speaker 1: map on their smartphone or out of their glove compartment
Speaker 1: and say, oh, yeah, this is where the Roman territory begins.
Speaker 1: But making a highly visible white wall like that is
Speaker 1: like making it is making the the the demarcation on
Speaker 1: the map physical in a way that you can see
Speaker 1: miles ahead. Yeah, exactly. So it's meant to stand out
Speaker 1: visually for psychological impact and to bolster that. Also, I
Speaker 1: mentioned the idea of the Antonine Wall the wall that
Speaker 1: not as not as big as Hadrian's Wall, but it's
Speaker 1: a little bit north of it. I was reading an
Speaker 1: article from last year about the research of an archaeologist
Speaker 1: named Luisa Campbell from the University of Glasgow and some
Speaker 1: colleagues of hers, who have found that the wall was
Speaker 1: also brightly painted in its time with yellow and red
Speaker 1: paints and decorated with all these bits of propagandistic sculpture
Speaker 1: to show the power of rome and like. There was
Speaker 1: a lot of emphasis on the use of red paint
Speaker 1: to show like power and bloodiness. So that would again
Speaker 1: this applies to the Antonine Wall, but would make it
Speaker 1: very much like a symbol, a signaling mechanism. Now I
Speaker 1: don't know which of these hypotheses is correct, obviously I'm
Speaker 1: not a historian of Roman Britain, but all of them
Speaker 1: seem at least somewhat plausible to me, Like the idea that, okay,
Speaker 1: it did serve some military purpose in a defensive sense,
Speaker 1: but it also or alternatively may have served mainly like
Speaker 1: a fundraising traffic controlling function to get traders into one
Speaker 1: place where you could tax them, Or that it was
Speaker 1: just a big make work project, or that it was
Speaker 1: mainly about symbolism, and as you mentioned a minute ago,
Speaker 1: that the symbolism could wouldn't just be going one way, right, Like,
Speaker 1: symbolism could be aimed at the people within your territory
Speaker 1: of control as well. Right, Yeah, this is the this
Speaker 1: is the place where are our rule extends to and
Speaker 1: and you are safe within these these walls. Yeah, like
Speaker 1: there there there's definitely a lot of writing about historical walls, especially,
Speaker 1: I know I've read one medieval historian talking about city
Speaker 1: walls in this context being about a sense of security
Speaker 1: versus necessarily like truly fully effective security. Because what you know,
Speaker 1: what do you need to happen in a city? You
Speaker 1: want there to be commerce, You want people coming in
Speaker 1: doing business, trading, you know that, to help make the
Speaker 1: city rich. And so a way to do that is
Speaker 1: to try to create a psychological effect and impression on
Speaker 1: people that this is a safe place to do business.
Speaker 1: And a wall could help do that. Yeah, and the
Speaker 1: idea that yes, the gates are open, but we have
Speaker 1: control over the gates. Uh, this this place is closed
Speaker 1: off and yet open to whatever degree we need it
Speaker 1: to be. Yeah. And again, so I don't feel qualified
Speaker 1: to adjudicate which of these historical interpretations for Hadrian's Wall
Speaker 1: in particular is correct, like which is which was the
Speaker 1: real main purpose of the construction. But I do think
Speaker 1: it's clear that very often barrier walls all throughout history
Speaker 1: are presented as simple and intended function, but in fact
Speaker 1: that they're complex and they may serve many purposes other
Speaker 1: than the explicitly announced one, often symbolic or psychological purposes,
Speaker 1: right and and whatever whatever. And even if they don't
Speaker 1: have the symbolism in mind, like overtly in mind when
Speaker 1: they are designed and built, they'll often take on this
Speaker 1: symbolic power as well. Uh, you know, I I can't
Speaker 1: help but think of some of the more modern examples
Speaker 1: of walls, you know, stuff that we can we can
Speaker 1: relate to with our through modern culture, for instance, the
Speaker 1: Berlin Wall being a primary example of that. Well, I
Speaker 1: mean think of the power of like how come the
Speaker 1: fall of of Soviet or Communist rule in Europe is
Speaker 1: put into a single image in the crushing and destruction
Speaker 1: of the Berlin Wall. You know that that one day, Uh, this,
Speaker 1: this is clearly such a powerful image for people, and
Speaker 1: it's all there on that one wall. Oh yes, plus
Speaker 1: all those wonderful images of the intense UH graffiti creativity
Speaker 1: that went into the one side of the wall versus
Speaker 1: a the starkness that that one encountered on the other.
Speaker 1: And it does feel that it was it was largely
Speaker 1: created UH with that symbolic power in mind, though, the idea,
Speaker 1: I mean, not the the artistic flourishes that were added
Speaker 1: to one side, but just the idea that here is
Speaker 1: a thing to represent the division. Here is a thing
Speaker 1: to to drive home the division while also functionally separating
Speaker 1: people's But then, of course we shouldn't forget that this
Speaker 1: wall was quite literally I think, meant to be effective
Speaker 1: at preventing transit, at least especially one way, like it
Speaker 1: definitely had a had a functional purpose. I mean, it
Speaker 1: was manned and guarded with lethal force. Speaking of which,
Speaker 1: another barrier that comes to mind is the Korean Militarized
Speaker 1: Zone or the d m Z, which of course snakes
Speaker 1: across the width of the Korean peninsula, creating this hundred
Speaker 1: sixty mile long, two and a half mile wide buffer
Speaker 1: zone between North and South Korea. Another barrier border that
Speaker 1: is frequently in the news. Another another one that Dolphin
Speaker 1: comes up is the West Bank Barrier UM. This one
Speaker 1: currently runs along the our myst disagreement line or the
Speaker 1: green line that separates Israel from the territories of the
Speaker 1: West Bank. And another one that is UH I've seen
Speaker 1: making the news recently are the Peace lines or the
Speaker 1: peace walls. UH. These are separation barriers built in Northern
Speaker 1: Ireland to separate Catholic and Protestant neighborhoods, intended to men
Speaker 1: minimize violence between the two groups, especially during the troubles
Speaker 1: from nine. But they're they're still standing. UH. You'll see
Speaker 1: them mostly in Belfast, but there of course is UM.
Speaker 1: In on the subject of of Brexit, there has been
Speaker 1: a lot of concern over this because currently you have
Speaker 1: a what a soft border between the Republic of Ireland
Speaker 1: and Northern Ireland, and um you have in the case
Speaker 1: of a what a hard Brexit, you have the potential
Speaker 1: for that to be a hard border. Again. UM. You know,
Speaker 1: not necessarily a wall in the strictest sense of the words,
Speaker 1: but when we're talking about like the channeling of commerce
Speaker 1: and the controlling of commerce and the UH and and
Speaker 1: so forth, it is it is essentially the wall and
Speaker 1: everything but form. And that sounds like a nasty echo
Speaker 1: of the past. Yeah, but you know, certainly speaking to it,
Speaker 1: two walls like the piece walls that that still stand,
Speaker 1: you know, like they're a constant reminder of what has
Speaker 1: come before and what you know, to some extent still
Speaker 1: resonates within the culture and what could come again. Um,
Speaker 1: you know, I mean, walls are potent reminders, potent symbols
Speaker 1: of division, and very often perceived to be symbols of oppression. Yeah,
Speaker 1: I mean, certainly that's the case if one is trapped
Speaker 1: within walls, if you were within the walls of a
Speaker 1: prison cell or a prison ground, um, you know, you
Speaker 1: can feel the force of those walls, and likewise it's
Speaker 1: communicating something else to the people on the outside, right saying, Uh,
Speaker 1: those that we have deemed appropriate to incarceraate are are
Speaker 1: safely set aside from you. They are they are walled
Speaker 1: off within this prison. Again back to the symbolic and
Speaker 1: psychological power that these barriers so often served. So we
Speaker 1: only mentioned a few walls. Obviously there are there there
Speaker 1: are a number of other historic walls of note. Uh
Speaker 1: number of other walls that are currently used in today's world.
Speaker 1: I hope coming out of this episode and sort of
Speaker 1: trying to deconstruct what a wall is and what it does,
Speaker 1: and what it doesn't do, what it depends on, all
Speaker 1: these other things. For uh that it will you know,
Speaker 1: force us to maybe you know, think twice, think three
Speaker 1: times if we need to, uh, the next time any
Speaker 1: of these barriers comes up, uh in conversation in the
Speaker 1: news cycle. Certainly we can think about the nature of
Speaker 1: walls in discussions of proposed future walls. Um. Again, the
Speaker 1: wall is something that is so universal it is easy
Speaker 1: to just not think about it, to not think about
Speaker 1: what it is and what it is supposed to do.
Speaker 1: A wall is something that's so simple in form it
Speaker 1: it almost asks to be taken very much at face value.
Speaker 1: But given what we know about history, we we should
Speaker 1: do exactly the opposite. I mean, you shouldn't just take
Speaker 1: it at face value. It's actually, uh, this almost kind
Speaker 1: of magical, talismanic kind of thing. Yeah, really coming back
Speaker 1: around to the idea of of a wall as a
Speaker 1: kind of magical spell. You know, we mentioned Game of Thrones,
Speaker 1: but we really didn't get into fictional walls much at all.
Speaker 1: But when we look to literature, films, music, their walls
Speaker 1: pop up quite frequently. I mean, one key example being
Speaker 1: Pink Floyd's uh treatment of the Wall. You can tell
Speaker 1: a lot about a person by what Pink Floyd they
Speaker 1: like best. Do they like the like dark, screaming, depressing
Speaker 1: like the Wall and UH animals kind of Pink Floyd,
Speaker 1: Or do they like the classic rock radio dark side
Speaker 1: of the moon kind of pink Floyd. Or do they
Speaker 1: like the psychedelic, freak out astronomy dominate kind of pink Floyd.
Speaker 1: That's like, that's basically the three kinds of humans. No,
Speaker 1: it's not, that's right. There would have to be at
Speaker 1: least a fourth category for people who don't like pink Floyd. Yeah,
Speaker 1: and maybe there's another category for people who just like
Speaker 1: the song the Warrior Shooting at the Walls a heart heartache, yeah,
Speaker 1: shooting out, Yeah, you know what? That is my favorite
Speaker 1: the Wall song. Absolutely. All right, Well, now it's time
Speaker 1: for us to stop as well. Obviously, we'd love to
Speaker 1: hear from everybody out there, your experience with with walls,
Speaker 1: some of your favorite examples from history and modern times,
Speaker 1: your favorite examples from from film and literature and music.
Speaker 1: All that is fair game. You can find us online
Speaker 1: the mother ship for this particular podcast is invention pod
Speaker 1: dot com. That's where you'll find all the episodes of
Speaker 1: the show that we've put out so far, as well
Speaker 1: as uh a few links out to social media and
Speaker 1: if you if you want to support the show, I
Speaker 1: would say the best thing you can do is to
Speaker 1: rate and review Invention wherever you have the power to
Speaker 1: do so, and make sure that you've subscribed. Big thanks
Speaker 1: to Scott Benjamin for research assistance on this episode and
Speaker 1: to our excellent audio producer TORII Harrison. If you would
Speaker 1: like to get in touch with us directly with feedback
Speaker 1: on this episode, with suggestions for future topics, or just
Speaker 1: to say hello, you can email us at contact at
Speaker 1: invention pod dot com th week very day. You can
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