Speaker 1: Hey you welcome to Stuff to Blow your Mind. It
Speaker 1: is Saturday. It is time for another Vault episode. This
Speaker 1: is going to be Mud Part three, which originally published
Speaker 1: seven thirteen, twenty twenty three. Let's sync right into it.
Speaker 2: Welcome to Stuff to Blow Your Mind production of iHeartRadio.
Speaker 1: Hey you welcome to Stuff to Blow your Mind. My
Speaker 1: name is Robert Lamb.
Speaker 3: And I'm Joe McCormick, and we're back with part three
Speaker 3: in our series on mud. Yes, mud, regular mud wet soil,
Speaker 3: especially of the clay and silt sized particle variety. So
Speaker 3: in previous parts of the series, we talked about what
Speaker 3: mud is, what its physical properties are, the role it
Speaker 3: played in the history of shaping Earth's continents, and how
Speaker 3: life colonized those continents. We talked in the previous episode
Speaker 3: about many animal behaviors that relate to mud. We talked
Speaker 3: about pigs wallowing in mud, Arnold Schwarzenegger wallowing and mud.
Speaker 3: We talked about mud skippers and other animals whose lives
Speaker 3: involve mud in one way or another. But of course,
Speaker 3: mud also plays a big role in human culture and
Speaker 3: human technology, even in the building of many important human settlements.
Speaker 3: So that's what we're going to focus on today mud
Speaker 3: especially as a building material for humans.
Speaker 1: Yeah, yeah, the mud brick especially because you know, we
Speaker 1: could build things out of mud, I guess without forming
Speaker 1: some sort of a brick or you know, something to
Speaker 1: to stack, something to use, but it would be messy,
Speaker 1: it wouldn't be very effective. And that's where the mud
Speaker 1: brick comes into play here, and the ability to turn
Speaker 1: mud into this thing that then can be mass produced
Speaker 1: and used to build a variety of things. Brian M.
Speaker 1: Fagan features several chapters that touch on mud bricks in
Speaker 1: The Negreat Inventions of the Ancient World. In a chapter
Speaker 1: on dwellings with Kate, Spence pointed out that we we
Speaker 1: absolutely can't consider human dwellings and the development and advancement
Speaker 1: of materials and techniques without also taking into account the
Speaker 1: shape of human culture at a given time and the
Speaker 1: environment in which they're constructed.
Speaker 3: The series of episodes has repeatedly just forced me to
Speaker 3: think about the interesting web of back and forth interactions
Speaker 3: between inorganic geological conditions in certain places on Earth and
Speaker 3: the life and culture that arises there.
Speaker 1: That's right, that's right now. On that first count, that
Speaker 1: idea of you know what you know, where are people going,
Speaker 1: where are they living their lives in ancient times. You know,
Speaker 1: as we've discussed before, there are modes of life and
Speaker 1: technology that makes sense if you're settled long term in
Speaker 1: a single area, But other modes make more sense if
Speaker 1: you're nomadic or semi nomadic, as many of our global
Speaker 1: ancestors were. So for nomadic peoples, it might make more
Speaker 1: sense to depend for shelter on some manner of say
Speaker 1: wood frame plus hide tense scenario, or to depend on
Speaker 1: very fixed, even naturally occurring shelters that you could take
Speaker 1: advantage of periodically, such as caves. There's also room in
Speaker 1: this for more permanent structures that seasonal settlements, places that
Speaker 1: you're going to come back to again and again, you know,
Speaker 1: when the seasons allow it, or the you know, crops,
Speaker 1: movements of animals, whatever happens to be the case, and
Speaker 1: then there are going to be you know, other modes
Speaker 1: of temporary constructions that are going to make sense as well.
Speaker 1: But the other main point is that of climate and environment.
Speaker 1: What is possible in a given area from a local
Speaker 1: material standpoint, would for example, makes an excellent material for
Speaker 1: building in ancient times as well as in our own
Speaker 1: modern world. But if it's harder to come by, if
Speaker 1: it has to be imported, et cetera, then it may
Speaker 1: make more sense to use it only for key roles
Speaker 1: such as is for instance, framing, and lean more heavily
Speaker 1: on other materials that are easier to acquire.
Speaker 3: Makes sense. Yeah.
Speaker 1: Now, Spence does note in their chapter that the thing
Speaker 1: about many ancient building supplies is that they simply don't
Speaker 1: survive the passage of time. But we know our ancestors
Speaker 1: used wood and even bones as tent structures between twenty
Speaker 1: five and twelve thousand years ago in Eurasia at Jericho,
Speaker 1: which this book site says at least at the time,
Speaker 1: the earliest evidence of occupation there dated back to before
Speaker 1: nine thousand BCE, and it seems that the earliest houses
Speaker 1: there were built out of quote unquote clay lumps and
Speaker 1: probably also made use of wooden building frames before they
Speaker 1: transition to mud brick buildings. For first first circular in nature,
Speaker 1: and then later they used rectangular designs with multiple rooms.
Speaker 3: So tell me about mud bricks.
Speaker 1: Okay, so mud bricks are pretty fascinating. I didn't expect
Speaker 1: to get so into mud bricks, but this book, and
Speaker 1: then another one I'm going to refer to in a
Speaker 1: bit really get into it and made me appreciate them. So,
Speaker 1: mud bricks are especially useful in arid environments because mud bricks,
Speaker 1: like other forms of solid masonry, are poor conductors of heat.
Speaker 1: Thick walls of mud brick will slow the rate at
Speaker 1: which the exterior solar heat is absorbed into the interior.
Speaker 3: Environment, so they're good insulators if you're living in say,
Speaker 3: a hot desert.
Speaker 1: Yeah. And additionally, structures like this, which are still common
Speaker 1: throughout North Africa, the author notes here, often feature high
Speaker 1: ceilings and small openings set high in the wall to
Speaker 1: encourage airflow. Also flat roofs since there tends to be
Speaker 1: less rainfall to contend with. So it's a design that
Speaker 1: has stood the test of time. It's the building material
Speaker 1: that is stood the test of time. Now, the thing is,
Speaker 1: of course, all buildings in general require upkeep, no matter
Speaker 1: what you're building in them out. Modern buildings upkeep as well,
Speaker 1: But of course mud brick buildings require regular upkeep against erosion.
Speaker 1: That is specific to the nature of mud bricks, and
Speaker 1: we'll get into that more in just a bit as well. Now,
Speaker 1: in the seventy grade Inventions of the Ancient World. It's
Speaker 1: later noted in a chapter with Jeffrey P. Killen that
Speaker 1: mud bricks were also used in the construction of furniture,
Speaker 1: such as among the poorer classes. In ancient Egypt, Wood
Speaker 1: and ivory were materials of the wealthy, while mud brick
Speaker 1: platforms served as beds by night and benches by day
Speaker 1: for common folk.
Speaker 3: As a side note on the subject of ancient Egyptian beds,
Speaker 3: if you've never seen ancient Egyptian the head rests, you
Speaker 3: should look that up. Where instead of pillows, they would
Speaker 3: have sort of a stand for your head to lie on,
Speaker 3: like a rigid stand. I find that really interesting.
Speaker 1: Yeah, we didn't we discuss this in the Invention of
Speaker 1: the Bed episode.
Speaker 3: Yeah, memory Serves.
Speaker 1: We talked about the work of a researcher who was
Speaker 1: like recreating these and testing them out.
Speaker 3: Unfortunately, I don't remember what the conclusions of that were,
Speaker 3: but yeah, very interesting. So imagine instead of a soft pillow,
Speaker 3: you use like a little hard podium for your head
Speaker 3: to lie on.
Speaker 1: Now elsewhere in this book, it also points out that
Speaker 1: extensive town walls appeared in the sixth and fifth centuries BCE,
Speaker 1: often constructed of mud bricks, but with stone facing or
Speaker 1: and or rubble filling. An example of this would be
Speaker 1: the long walls of classical Athens. These were destroyed by
Speaker 1: the Roman general Sula during the first century BCE, and
Speaker 1: they had been rebuilt even before that. So you know,
Speaker 1: it's the nature of fortifications. And then also you know
Speaker 1: that some of the part of it also is the
Speaker 1: nature of mud bricks, which we'll come back to. By
Speaker 1: the third century BCE, mud bricks were a common material
Speaker 1: in the construction of walled cities among various Mediterranean civilizations,
Speaker 1: according to Fagan. Now, one something that also comes up
Speaker 1: in these chapters is that mud bricks would have also
Speaker 1: been used in the construction of what was considered an antiquity,
Speaker 1: one of the seven Wonders of the ancient world, the
Speaker 1: hanging gardens of Babylon or the garden terraces of Babylon
Speaker 1: that are often attributed to the ruler Nebechonezer, who lived
Speaker 1: six oh five through five sixty two BCE.
Speaker 3: Now, when I was a kid, I had a little
Speaker 3: booklet that I read a lot that was about the
Speaker 3: seven wonders of the ancient world, and one of them
Speaker 3: was the hanging gardens of Babylon, And I never understood
Speaker 3: what the deal with the word hanging was. I was
Speaker 3: imagining them like dangling from chains, but what were those
Speaker 3: dangling from? I didn't get the hanging part.
Speaker 1: Yeah, and it seems that a more accurate description would
Speaker 1: be terraced. We're essentially talking about great terraced gardens. So
Speaker 1: I wanted to get into this a little bit more
Speaker 1: because you know, obviously if something's being held up is
Speaker 1: one of the wonders of the age is during this time,
Speaker 1: and it was made out of mud bricks, mud bricks
Speaker 1: being something that you know, you might without knowing much
Speaker 1: about it, you might just think, well, this is a
Speaker 1: simplistic this is an old fashioned form of construction. Well,
Speaker 1: let's look a little deeper. So I picked up a book.
Speaker 1: This is a new book came out just this year
Speaker 1: that we've actually been been in discussions with having the
Speaker 1: author on the show. Even it's such a neat looking volume.
Speaker 1: It's titled The Seven Wonders of the Ancient World, Science, Engineering,
Speaker 1: and Technology by Michael Dennis Higgins. It's a great book.
Speaker 1: It looks at not only what's historically known and or
Speaker 1: alleged regarding these wonders and how it ties into what
Speaker 1: we know about the geology of the regions where these
Speaker 1: wonders were located or thought to be located, but also
Speaker 1: what recreation in the modern world might look like. So
Speaker 1: Chapter three of the book deals with the Gardens of Mesopotamia,
Speaker 1: because while the traditional view Higgins rides is that the
Speaker 1: gardens were set in the walled city of Babylon and
Speaker 1: what is now central Iraq just south of Baghdad during
Speaker 1: the sixth century BCE, there is also growing support for
Speaker 1: the idea that they weren't located here at all, but
Speaker 1: were in Ninevah during the seventh century BCE, in what
Speaker 1: is now northern Iraq near mosul Oh.
Speaker 3: So that would make sense because then I would assume
Speaker 3: that would mean they wouldn't be the gardens of Babylon
Speaker 3: but of Assyria, right because Ninevah was the capital of Assyria,
Speaker 3: but still would have been between the rivers, still would
Speaker 3: have been Mesopotamia.
Speaker 1: Yeah. One thing that that Higgins stresses, and we have
Speaker 1: to keep in mind with the Wonders of the ancient world,
Speaker 1: the seven Wonders of the Ancient World, is that these
Speaker 1: were these this was like a list that was that
Speaker 1: was put together in the Hellenistic world, and the concerning
Speaker 1: things that were often far away. And this is especially
Speaker 1: the case. These were the This, These were the East.
Speaker 1: This was the east most wonder on the list by
Speaker 1: a considerable margin, and it was so far away that
Speaker 1: you could basically say whatever you wanted and it would
Speaker 1: not be questioned.
Speaker 3: I've often thought of the writings about these as kind
Speaker 3: of the Forbes travel Guide of the ancient Greeks, but
Speaker 3: maybe with some shaky sourcing.
Speaker 1: Yeah, because again, the idea of the seventh Wonders of
Speaker 1: the Ancient World are basically a first century BCE creation,
Speaker 1: and in this particular case, they're dealing with something from
Speaker 1: the sixth or seventh century BC. Higgins writes, quote, we
Speaker 1: will never know definitively the where and when of the gardens,
Speaker 1: and it is likely that more than one Mesopotamian ruler
Speaker 1: had remarkable gardens that may have been conflated in stories
Speaker 1: and accounts relayed to the far off Mediterranean world. Higgins
Speaker 1: also had this other great little addition. He says, quote,
Speaker 1: we should perhaps be wary of imposing a modern view
Speaker 1: of garden life. In one panel from the north palace
Speaker 1: of Ashur, Banipal, king of the Neo Assyrian Empire from
Speaker 1: six sixty nine through six point thirty one BCE. The
Speaker 1: king is taking refreshments while listening to music with his
Speaker 1: wife amid luxuriant trees, from one of which hangs the
Speaker 1: severed head of an enemy. So I don't know quite
Speaker 1: what to make of that, but fair enough.
Speaker 3: Well, you like to celebrate your accomplishments, and that can
Speaker 3: take many forms.
Speaker 1: Yes, anyway, onto the bricks. So their role in the
Speaker 1: construction of the gardens would vary depending on where exactly
Speaker 1: this garden would have been. Higgins writes that there are
Speaker 1: five ancient descriptions of the gardens. The most detailed stems
Speaker 1: from Greek writer Deodora Siclis during the first century BCE,
Speaker 1: but he does not identify the actual city where this
Speaker 1: is supposed to be, and he also doesn't name the ruler.
Speaker 1: All he says is that it is a quote Syrian king. Still,
Speaker 1: there are a lot of details mentioned in this account,
Speaker 1: and it specifically mentions bricks. He describes ascending tiered terraces
Speaker 1: full of abundant plat life, made level with the opposing
Speaker 1: battlements of the city opposing as in like they're inside
Speaker 1: the city and they're looking at the you know, their
Speaker 1: opposite an interior wall. So this particular account describes that
Speaker 1: the roofs over a series of galleries were layered with
Speaker 1: stone beams. Then they put down a layer of reeds
Speaker 1: and bitumen. Then two courses of baked bricks bonded by
Speaker 1: cement were put over this. And we'll have more on
Speaker 1: baked bricks in a minute. Then there's a layer of
Speaker 1: lead to prevent moisture from creeping down, and then enough
Speaker 1: dirt and soil on top of all that to accommodate
Speaker 1: the roots of quote the largest trees. So a considerable
Speaker 1: garden project any way you look at it, like definitely
Speaker 1: more involved than anything any of us are doing in
Speaker 1: our backyards. Okay, so I mentioned baked bricks. When it
Speaker 1: come to mud bricks specifically, so Higgins stresses that these
Speaker 1: were mud bricks were the most important building material in
Speaker 1: Mesopotamian cities, and this was especially true of Babylon, which
Speaker 1: had no outcroppings of stone in the immediate area Nineveh.
Speaker 1: On the other hand, up there there was a local
Speaker 1: supply of limestone, so they were able to lean on
Speaker 1: that much more for their construction needs. However, mud bricks
Speaker 1: were still used there because they were traditional and or inexpensive.
Speaker 3: All right, So you could quarry out stone bricks up
Speaker 3: in ninev if you need them, but mud bricks are
Speaker 3: still just cheaper and more efficient in many ways. And
Speaker 3: you know, there were something people were used to using
Speaker 3: and they get the job done.
Speaker 1: Right right now. The process of making the mud bricks
Speaker 1: is also very important here, and I thought very interesting.
Speaker 1: I just never had looked into this before, but in
Speaker 1: this particular, their mud bricks you used throughout arid parts
Speaker 1: of the world where people have settled, but these specifically,
Speaker 1: these would have been sediments washed down the tigris and
Speaker 1: euphrates from what is now Turkey. Then people would collect
Speaker 1: the mud and then they would mix in fresh straw.
Speaker 1: This would give the mud bricks, once they had had
Speaker 1: time to dry, additional strength. And this reminded me of
Speaker 1: our episode on Pie Create Joe about creating building materials
Speaker 1: out of ice and how something had to be added,
Speaker 1: something had to be mixed in there with it to
Speaker 1: give them additional stability.
Speaker 3: What was it? Was it, like, I want to say,
Speaker 3: like chopped up newspaper or straw or sawdust or something
Speaker 3: to that effect.
Speaker 1: Yeah, yeah, so fresh straw would be serving the purpose here,
Speaker 1: and it does seem like it did need to be fresh,
Speaker 1: and we'll come back to that in a second. Then,
Speaker 1: so you have the mud you've added in the fresh straw.
Speaker 1: Then you mold these into more or less uniform brick shapes,
Speaker 1: and then you leave them to air dry. And then
Speaker 1: once dry, you know today you have bricks for building
Speaker 1: all sorts of structures. So this began as mud, but
Speaker 1: it ends up being sturdy enough to build with, right,
Speaker 1: So there are some pros and cons here. So the
Speaker 1: pros the big pro of course, is that these are
Speaker 1: inexpensive and they don't require high temperature, fuel consuming ovens
Speaker 1: to bake them as you have with with baked bricks.
Speaker 1: You can make a ton of them. You can use
Speaker 1: them to build battlements, buildings, et cetera in pretty short order.
Speaker 3: So again they're they're cheap, they're fast building material to
Speaker 3: make them as abundant and they get the job done right.
Speaker 1: And I don't want to imply that, you know, there's
Speaker 1: just a crude mode of construction, Like obviously there's an
Speaker 1: art and a craftsmanship to making them, And I think
Speaker 1: that's key here too, Like the local people knew how
Speaker 1: to make them. There was a tradition of making them,
Speaker 1: and that also allowed them to bust them out in
Speaker 1: massive quantities in a short amount of time.
Speaker 3: Oh yeah, I want to be clear by saying like
Speaker 3: that they're inexpensive, I mean that they're you know, they're
Speaker 3: inexpensive relative to like quarrying or having to fire the
Speaker 3: bricks in an oven. But that doesn't mean that they're
Speaker 3: like junk. I mean this is this is building material
Speaker 3: that serves its purpose and it is efficient, it's smart.
Speaker 1: Now there are cons here. Of course, these are arid environments,
Speaker 1: but it doesn't mean that it doesn't rain. It doesn't
Speaker 1: mean that there aren't floods, periodic flooding and so forth.
Speaker 1: So yeah, they're easily washed away or damage during storms.
Speaker 1: Plus this was impressive. As Higgins points out, the bricks
Speaker 1: at the base of walls of structures draw up and
Speaker 1: absorb water by capillary action. The water evaporates, but quote,
Speaker 1: salts are concentrated and finally crystallized between the mineral grains,
Speaker 1: causing the mud to flake, weakening the base of the walls.
Speaker 1: And he also has this was especially true would have
Speaker 1: been true in Babylon due to the rather brackish ground water.
Speaker 3: Yeah. Okay, so higher salt content in that water, more
Speaker 3: more crystals getting into the bricks. Yeah.
Speaker 1: So, mud brick buildings, while essential for the time period,
Speaker 1: also required a lot of upkeep, and they would eventually fail.
Speaker 1: Mud brick buildings would eventually crumble and fall apart, and
Speaker 1: any resulting bricks would not be reused, nor would the mud.
Speaker 1: Like you couldn't just like you know, essentially wet it
Speaker 1: all down and form new mud bricks out of that mud,
Speaker 1: out of that soil. And it's thought that a lot
Speaker 1: of this had to do with the fact that at
Speaker 1: this point it's all it's old straw mixed in there,
Speaker 1: and it's not going to hold things together as well
Speaker 1: as fresh straw. So you would get fresh mud from
Speaker 1: the river, you would add fresh straw to that, and
Speaker 1: you would just build new new bricks the old side
Speaker 1: the crumbled bricks, et cetera. You would just flatten that
Speaker 1: down as much as possible, and that would service the
Speaker 1: foundation for the new structure. And it's interesting that resulting
Speaker 1: mound of old mud bricks is what we call it.
Speaker 1: Tell this is a rising heap where these would these
Speaker 1: buildings would crumble, they'd have to be flattened. You'd build
Speaker 1: a new one that eventually would crumble and be flattened. Higgins'
Speaker 1: rights that over the millennia, such tells actually lifted the
Speaker 1: base levels of cities up above the plane, making them
Speaker 1: more defendable, making them more desirable as places to live
Speaker 1: and to work and to defend yourself. And therefore the
Speaker 1: pattern would just continue.
Speaker 3: Yeah. And so you can see in the locations or
Speaker 3: ruins of some ancient settlements, especially in the ancient Near East,
Speaker 3: that maybe even no buildings remained, but there's just a
Speaker 3: big mound built up off the ground. Yeah.
Speaker 1: So that's that's that's incredible. So anyway, the problems of
Speaker 1: mud bricks were known, even though they were traditional, even
Speaker 1: though they were inexpensive. Higgins points out that not only
Speaker 1: is Babylon home to some of the early is known
Speaker 1: recorded legal systems, but also some of those laws that
Speaker 1: were recorded concerned building collapses. It was written that if
Speaker 1: a building's collapse caused the death of the homeowner, then
Speaker 1: the builder would be put to death.
Speaker 3: Oh wow, that is a strict building code.
Speaker 1: Yeah, but you know, it makes sense you're building, I mean,
Speaker 1: not to say the eye for an eye nature of it.
Speaker 1: You know, it makes it makes sense so much. But
Speaker 1: just the idea that like, buildings are important and there
Speaker 1: has to be some sort of you know, some sort
Speaker 1: of law in place to make sure things are built
Speaker 1: to code.
Speaker 3: Yeah, maybe not a death penalty, but builders should be
Speaker 3: kept to a high standard. Yeah.
Speaker 1: Yeah. And so you know, again, it was known that
Speaker 1: there could be problems with mud bricks, and it was
Speaker 1: discovered early on that you could transform mud bricks of
Speaker 1: a sort into something harder and less susceptible to erosion.
Speaker 1: Higgins writes, quote, heat changes water bearing clay minerals with
Speaker 1: their slippery playing card structure, into larger, interlocking crystals of
Speaker 1: minerals containing less water, which makes a stronger material than
Speaker 1: is water resistant. He ultimately compares this transformation to kind
Speaker 1: of a sped up and you know, less sophisticated process
Speaker 1: of metamorphism that in like in the ground and over
Speaker 1: geologic time, produces things like marble. And so he writes
Speaker 1: that many of the great Babylonian structures of the day
Speaker 1: would have been made of baked bricks, and these would
Speaker 1: ultimately last so long that they would be reused long
Speaker 1: after the final fall of Babylon to build such cities
Speaker 1: as Baghdad. And we see this in other parts of
Speaker 1: the world as well, like the bricks stand the test
Speaker 1: of time, and then the bricks are scavenged in order
Speaker 1: to build the new cities of an emerging new world.
Speaker 3: But these would have been fire bricks, bricks, yes.
Speaker 1: These would been the fired Yeah, you're not doing this
Speaker 1: with mud bricks at all, But baked bricks are just
Speaker 1: that much more durable. And you know, and it's interesting.
Speaker 1: I was been talking about this with my wife and
Speaker 1: she pointed out that, you know, a lot of the
Speaker 1: bricks we see on houses today, like they're they're purely ornamental.
Speaker 1: They're real baked bricks, but they're not like doing much
Speaker 1: or anything in the way of structural support for the house.
Speaker 1: Your house isn't built out of bricks. It's built out
Speaker 1: of wood framing and all the other stuff. But the
Speaker 1: bricks are there just for ornamental purposes, well, depending on
Speaker 1: the house. But yeah, in a lot of modern uses.
Speaker 3: Yeah.
Speaker 1: Now, Higgins points out that limestone was also used in
Speaker 1: special instances, but this would have been expensive to import
Speaker 1: in Babylon, unlike with with Nineveh. The walls of Babylon, however,
Speaker 1: were also sometimes listed as an ancient wonder in and
Speaker 1: of themselves. They were made of mud bricks, and the
Speaker 1: gates faced with with with baked bricks that were glazed
Speaker 1: with a glass like blue glaze that was then detailed
Speaker 1: with yellow flora and fauna things like lions and all.
Speaker 1: So so these walls would have begun depended mostly on
Speaker 1: baked bricks for their bulk and their protective qualities, but
Speaker 1: then you also had glazed baked bricks that made them
Speaker 1: beautiful to behold and spoke of the you know, the
Speaker 1: glory of the city and its ruler. So Higgins goes
Speaker 1: into a lot more detail in the book about all
Speaker 1: of this, and especially gets into the geology of the region.
Speaker 1: But I think just what we've we've drawn out here already,
Speaker 1: it provides a nice glance at the importance of mud
Speaker 1: bricks in the ancient world, their pros and cons, and
Speaker 1: also how they serve as a necessary predecessor to baked
Speaker 1: brick technology that would basically serve as the next step
Speaker 1: in humanity's ability to take essentially mud and remake it
Speaker 1: as solid earth for our own purposes. And how fitting
Speaker 1: too that this occurred in the shadows of the Ziggurats,
Speaker 1: holy mountains constructed by human ingenuity.
Speaker 3: Now from here I wanted to talk about one specific
Speaker 3: example of amazing mud based construction practices that still exists
Speaker 3: in the world today, and that is the example of
Speaker 3: the mud built skyscrapers of the city of Shibomb. So
Speaker 3: I was reading about this in a number of sources.
Speaker 3: One of the main ones out site is an entry
Speaker 3: in the Encyclopedia of Architectural and Engineering Feats edited by
Speaker 3: Donald Longmead and Christine Garneault, published in two thousand and one.
Speaker 3: So the city of Shibam is located in modern day Yemen.
Speaker 3: It is situated on top of a rock spur at
Speaker 3: the southern tip of the rub Al Khali Desert of
Speaker 3: the Arabian Peninsula and the Rublkali. That name means empty quarter.
Speaker 3: This is an area of approximately one thousand by five
Speaker 3: hundred kilometers covered in sand dunes, with relatively little human
Speaker 3: habitation and plant and animal life compared to other areas.
Speaker 3: It is a hyper arid desert of wind swept dunes
Speaker 3: of sand. So this is near the southern end of
Speaker 3: that area, sort of where it's transitioning into other sort
Speaker 3: of ecoregions. Many of the buildings that still stand in
Speaker 3: the city of Shabam today date back to the sixteenth century,
Speaker 3: though the settlement itself is older. Several sources I was
Speaker 3: looking at said it went back to the third century CE.
Speaker 3: The population of the city in the modern era is
Speaker 3: roughly seven thousand, and most of these people live in
Speaker 3: these mud brick high rise houses. There are more than
Speaker 3: five hundred of these structures inside the city walls. I've
Speaker 3: seen vastly conflicting estimates on the height of the tallest ones.
Speaker 3: The Encyclopedia entry I just cited says that some of
Speaker 3: them are up to twelve stories tall. Other sources say
Speaker 3: the tallest are more like seven stories. I don't know
Speaker 3: what accounts for that difference, but I bet it depends
Speaker 3: on how you're counting the stories. Maybe it's height versus
Speaker 3: the actual number of occupied floors, because I think within
Speaker 3: those buildings the floors are actually quite tall, like the
Speaker 3: ceilings are high, and there will be multiple levels of
Speaker 3: windows within a single floor of the building.
Speaker 1: That would make sense too, based on some of the
Speaker 1: like the design parameters that are that are common with
Speaker 1: with with with this sort of climate and the sort
Speaker 1: of construction material like we referenced earlier.
Speaker 3: Right, because you want a lot of windows situated high
Speaker 3: up so that as hot air rises, it can flow
Speaker 3: out through those windows. So you get high ceilings, windows
Speaker 3: up near the ceiling above where the people are walking around.
Speaker 1: Now, I think people should if it's safe to do so,
Speaker 1: you know, not if you're driving the car, obviously, but
Speaker 1: you should look up images of this because when we
Speaker 1: say mud Rick high rises, or you hear a description
Speaker 1: like the Manhattan of the desert, which I've seen, you
Speaker 1: might you might not fully believe it, but because it
Speaker 1: is very almost unreal to behold. But yes, it does
Speaker 1: look essentially like parts of Manhattan in terms of the
Speaker 1: scope of the buildings and the height of the buildings,
Speaker 1: and the modernity of the buildings, you know, and their
Speaker 1: sort of basic shape and design. This does not look
Speaker 1: like a like like some sort of you know, archaic city.
Speaker 1: It looks at once modern and yet you can tell
Speaker 1: there's something about the building materials that is different. So
Speaker 1: it is this is a remarkable city that is rising
Speaker 1: up out of the desert here.
Speaker 3: Some sources have identified these as the world's oldest skyscrapers.
Speaker 3: I don't know how you make the cut for skyscraper,
Speaker 3: but they are very old buildings and very tall for
Speaker 3: their construction materials, so they are made of mud bricks.
Speaker 3: And yeah, you mentioned the sort of nickname used in
Speaker 3: some Western media, the Manhattan of the desert. As far
Speaker 3: as I know, the city of Shibam was first called
Speaker 3: that in the nineteen thirties. I think that it goes
Speaker 3: back to the British explorer Freia Stark who called it that.
Speaker 3: And speaking of how the city was described in Western
Speaker 3: media in the nineteen thirties, I found an article in
Speaker 3: an old issue of Popular Mechanics from nineteen thirty six
Speaker 3: called mud Skyscrapers of Desert built long before the log cabin.
Speaker 3: So it was just a little paragraph, but I wanted
Speaker 3: to read this because I thought it was funny. So
Speaker 3: it First the caption on the photo says centuries old
Speaker 3: city of Shabomb in southern Arabia is a cluster of
Speaker 3: sun hardened mud skyscrapers that have withstood tests of time
Speaker 3: and weather, and then the body text says mud skyscrapers
Speaker 3: that were hundreds of years old when log cabins began
Speaker 3: to dot the American wilderness still stand in the ancient
Speaker 3: city of Shabomb in southern Arabia, the modern steel skyscraper
Speaker 3: is only fifty years old. Shabomb was a thriving city
Speaker 3: of tall buildings in the time of the Queen of Sheba,
Speaker 3: and it still is a busy desert metropolis today, so
Speaker 3: constructed as to withstand the raids of hostile Arab tribesmen,
Speaker 3: with the windows high above the ground. The Shabamb skyscrapers
Speaker 3: were of mud mixed with straw and maize, dried and
Speaker 3: hardened by the desert sun. And then directly under that
Speaker 3: there's another headline that says insects killed by vaporizer heated electrically.
Speaker 3: But so, as Rob said, if you're able to look
Speaker 3: up images of the city of Shabam, you should because
Speaker 3: it's amazing looking. But if you can't, one thing you
Speaker 3: should understand is that the city itself has a notably
Speaker 3: small and tidy horizontal footprint. It is about half a
Speaker 3: square kilometer stretching up instead of out, and when it
Speaker 3: was recognized by UNESCO's World Heritage List in the nineteen eighties.
Speaker 3: I think it was nineteen eighty two. It was described
Speaker 3: as quote one of the oldest and best examples of
Speaker 3: urban planning based on the principle of vertical constructions. Now, Rob,
Speaker 3: I'm about to divulge something of great relevance to you personally.
Speaker 3: I know you love a skybridge. Well, a lot of
Speaker 3: the mud built high rises in Shibam are linked by
Speaker 3: upper floor floating corridors skybridges made out of mud. So
Speaker 3: I attached some photos here for you to look at.
Speaker 3: It looks, at least at least some of the photos
Speaker 3: I could find, it looks like the skybridges are not
Speaker 3: covered on top. I don't know if they're all like
Speaker 3: that or if it's just some of them, but in
Speaker 3: some of these photos it's like a walkway connecting the
Speaker 3: upper floors of these buildings that has a bottom, of course,
Speaker 3: and then it has walls rising up on the sides,
Speaker 3: but not a roof.
Speaker 1: Wow, this is amazing. Yes, I had no idea, but
Speaker 1: here they are. Yeah, the mud brick skybridges, I'll take it.
Speaker 3: So from what I've read, the design of the city
Speaker 3: with its mud walls all around it. Also, as I said,
Speaker 3: it has walls surrounding the city that are also made
Speaker 3: of mud brick. The design of the city, with the walls,
Speaker 3: the high rises and the sky bridges, is in large
Speaker 3: part defensive in nature. The city was built to defend
Speaker 3: itself against marauders. Now why, like, what would make this
Speaker 3: city in particular a target for such attacks. According to
Speaker 3: some sources, it may have a lot to do with
Speaker 3: frankincense and the Frankensense trade. Frankinson's traders used to have
Speaker 3: routes that crossed the Rubl Khali desert, and Shibam was
Speaker 3: a hub along one of those caravan routes. So there
Speaker 3: was a lot of frankensense trade and as a result,
Speaker 3: a decent amount of wealth associated with that. Now, Rob,
Speaker 3: as you mentioned, mud based buildings are great and that
Speaker 3: they have many wonderful properties, but they do need frequent upkeep.
Speaker 3: The walls have to be replastered on an ongoing basis
Speaker 3: to counteract erosion damage from wind and rain, and they
Speaker 3: also have to be built with the limitations of their
Speaker 3: construction materials in mind. So the mudd high rises here,
Speaker 3: they tend to have thicker walls near the bottom that
Speaker 3: become thinner as the stories go up. So the buildings
Speaker 3: kind of taper inward as they go up higher, and
Speaker 3: this is to reduce the weight load from higher floors
Speaker 3: pressing down on the bricks below, because again the walls
Speaker 3: are partially load bearing, though there are also some internal
Speaker 3: posts like timber posts that help bear the weight of
Speaker 3: the building as well. I was kind of surprised to
Speaker 3: learn that many of the houses here are actually occupied
Speaker 3: only by a single family. So often the family will
Speaker 3: live on the upper floors of the building, and then
Speaker 3: the lower floors are places that are traditionally used for
Speaker 3: storage of food, like grain storage and for livestock.
Speaker 1: That's fascinating, and I guess it would make sense too
Speaker 1: that you'd want to live on those upper floors because
Speaker 1: you would get more ventilation and so forth.
Speaker 3: Now, Shabam lies in a valley at the confluence of
Speaker 3: several waddies. A wady is a ravine or river channel
Speaker 3: in the desert that is dry most of the time,
Speaker 3: but then floods with water during the rainy season. And
Speaker 3: as often happens in desert environments, it can be very
Speaker 3: dry and then suddenly extremely wet when the rain comes.
Speaker 3: You know, so the flood comes in, and that can
Speaker 3: be very dangerous to human settlements, especially settlements made out
Speaker 3: of mud brick. Because of the placement at the convergence
Speaker 3: of these watties, Schabam is vulnerable to flooding and has
Speaker 3: suffered catastrophic flooding damage at various points in history, such
Speaker 3: as in fifteen thirty two. That's when a lot of
Speaker 3: the city had to be rebuilt. And why that's you know,
Speaker 3: as far back as most of the skyscrapers there today date. Now,
Speaker 3: why would you build high rises out of mud here
Speaker 3: instead of just more you know, regular low lane dwellings.
Speaker 1: Well.
Speaker 3: The entry in the Encyclopedia of Architectural and Engineering Feats
Speaker 3: identifies several reasons for the vertical expansion. One is because
Speaker 3: of the area's proneness to flooding. The city is situated up,
Speaker 3: as I said, on kind of a rockspur so it's
Speaker 3: raised up above the floor of the valley, but not
Speaker 3: raised up enough to totally avoid flood damage, and floods
Speaker 3: can threaten it. So one is protection from flooding. Another
Speaker 3: is preservation of horizontal acreage around the city for agriculture,
Speaker 3: because there are date palm groves all around, and so
Speaker 3: expanding the footprint of the city would essentially cut into
Speaker 3: the farmland around it.
Speaker 1: This detail makes for some really beautiful photos though, because
Speaker 1: you see those brilliant green date palms all around the
Speaker 1: outside walls of the city.
Speaker 3: Yes, another reason is the desire to gather families in
Speaker 3: a single building. I guess this means like even large families.
Speaker 3: And then finally to squeeze more of the city inside
Speaker 3: the protective perimeter wall, which again was to defend against
Speaker 3: raiders who might want to attack the city for its
Speaker 3: wealth associated with the Frankinson's trade. Now we've already covered
Speaker 3: how mud bricks are made, but how are these skyscrapers
Speaker 3: in particular put together. Well, they are made out of
Speaker 3: mud bricks as far as I can tell based on
Speaker 3: the normal method. So these would be mud reinforced with
Speaker 3: straw baked in the sun, which is stuccoed over on
Speaker 3: the outside of the buildings with a plaster made out
Speaker 3: of clay and chopped straw. And then this is all
Speaker 3: placed upon a stone foundation. As I said, the mud
Speaker 3: brick walls tend to taper inward and become thinner as
Speaker 3: they go up, because again the walls are partially load bearing.
Speaker 3: The buildings reach heights of forty meters or one hundred
Speaker 3: and thirty feet, and the walls of the ground floor
Speaker 3: are generally between one point three and two meters thick,
Speaker 3: so that's like four to six feet thick. There's a
Speaker 3: lot of it just seems to me a lot of
Speaker 3: energy efficiency in mind in the construction of the city
Speaker 3: because they have all these properties. But also like they
Speaker 3: have the skybridge bridges I mentioned, and that is to
Speaker 3: allow neighbors to visit one another without having to go
Speaker 3: up and down the stairs, you know, go up and down,
Speaker 3: wasting energy going that way. But then also the upper
Speaker 3: floors have this external white stucco to help reflect solar
Speaker 3: radiation and help keep them cool.
Speaker 1: I love I love this detail about the skybridge because this,
Speaker 1: like this lines up with the basic rationale for skybridges
Speaker 1: in the age of skyscrapers, and this sort of you know,
Speaker 1: forward thinking futuristic idea that like, well, life is going
Speaker 1: to be up there now and we need to move
Speaker 1: around up there building to building, and this is an
Speaker 1: example of it not really being a thoroughly futuristic idea
Speaker 1: at all, Like it's it's ultimately a much older, even
Speaker 1: ancient idea at least in places where you had tall
Speaker 1: buildings like this.
Speaker 3: Or maybe you could say been part of a smart,
Speaker 3: progressive technological framework for ages.
Speaker 1: Yeah, yeah, I think so, because I imagine imagine like coming
Speaker 1: to this city centuries ago, you know, and just how
Speaker 1: modern and advanced it would be. Like this was like
Speaker 1: the blade Runner city of the day.
Speaker 3: Now. A lot of the city's architecture centers around helping
Speaker 3: to deal with extreme heat. So one advantage of having
Speaker 3: tall buildings close together is that it really helps to
Speaker 3: provide shade within the city. Buildings also have a lot
Speaker 3: of windows to aid in ventilation, especially near the top,
Speaker 3: letting hot air out. But they also, like the doors
Speaker 3: in these buildings, many of them are carved wooden doors
Speaker 3: that will have like these beautiful geometric patterns carved into them,
Speaker 3: but they will have openings in the wood of the
Speaker 3: doors again to allow ventilation, you know, natural airflow through.
Speaker 3: And also in the city, I was watching one video
Speaker 3: documentary about it that showed the city still having some
Speaker 3: very old old school wooden locks, so like locks on
Speaker 3: doors that you would open by having a wooden paddle
Speaker 3: that has a particular arrangement of pegs poking up off
Speaker 3: of it. So you can reach the wooden paddle into
Speaker 3: the lock hole and you press it up and if
Speaker 3: it has the right arrangement of pegs, it lifts the
Speaker 3: what do they call it, the lifts the little tumblers,
Speaker 3: I guess, and then the lock opens. Some buildings in
Speaker 3: the city also have wooden mashrabias, which are if you
Speaker 3: don't know what that is, sort of like a wooden
Speaker 3: enclosed but ventilated deck area, sort of, I don't know
Speaker 3: the correct way to describe it. Look it up, Look
Speaker 3: up pictures of them. They are these beautiful external features
Speaker 3: that you see on a lot of buildings throughout the
Speaker 3: Islamic world.
Speaker 1: You know, coming back to what you said earlier about
Speaker 1: the setbacks and the design the idea that you know,
Speaker 1: they taper inward and there's kind of a terracing as
Speaker 1: they go up. And of course this applies to more
Speaker 1: than just mud brick buildings, but you know, thicker at
Speaker 1: the bottom, less mass towards the top. You know. This
Speaker 1: this makes me think of setbacks in like a modern
Speaker 1: city environment like New York City, where even when you
Speaker 1: get to the point where you don't need the setbacks
Speaker 1: from a structural standpoint, setbacks end up being desired, you know,
Speaker 1: well for I guess a couple of reasons. One just esthetically,
Speaker 1: but also you put these setback laws in place because
Speaker 1: you don't want to create the just like depths of
Speaker 1: shadow where the sun never shines. You know, you want
Speaker 1: there to be sort of more open sky in these
Speaker 1: these ravines between the skyscrapers. And yet also you know
Speaker 1: you touched on with with this city that you know,
Speaker 1: to a certain extent, those wells of shadow are also
Speaker 1: desired because you want to create to create some additional
Speaker 1: escape from the overbearing power of the sun.
Speaker 3: Yeah, that's right. So I guess again there are trade
Speaker 3: off there. As you know, building, building materials and architecture
Speaker 3: really is a story of trade offs, isn't it. Yeah.
Speaker 3: I don't know if that's a banal observation, I just
Speaker 3: it just occurred to me.
Speaker 1: Well, I think the banal becomes the spectacular when you
Speaker 1: start looking at examples like this that turn our understanding
Speaker 1: of skyscrapers and modern urban environments on their head by
Speaker 1: placing them in in a much older setting, in a
Speaker 1: different environment than we're used to contending with. So it's, yeah,
Speaker 1: such a fascinating model to look at. Now.
Speaker 3: One last thing is I was reading about some threats
Speaker 3: to this beautiful architectural heritage recently due to weather and
Speaker 3: especially due to conflict in Yemen, leading to difficulty in
Speaker 3: performing the upkeep necessary to keep these buildings standing. And
Speaker 3: all that, there was apparently a tropical cyclone in two
Speaker 3: thousand and eight that caused a lot of flooding and
Speaker 3: damage to buildings in Shabam. And also I think there
Speaker 3: are some other settlements in the same region that have
Speaker 3: some similar construction and architecture in them that are also
Speaker 3: under threat due to flooding and weather and just lack
Speaker 3: of ability to perform the necessary upkeep. So I know
Speaker 3: there are some restoration and maintenance projects that are underway.
Speaker 3: I think UNESCO might be involved in something going on there.
Speaker 3: But it would be a shame to see this beautiful
Speaker 3: and ingenious architectural tradition, which is in a way it's
Speaker 3: a tradition that's ongoing because of the upkeep you always
Speaker 3: have to do to keep these buildings alive to see
Speaker 3: that go away.
Speaker 1: So yeah, now we also want to stress though that
Speaker 1: of course this is just one of the phenomenal examples
Speaker 1: of mud brick based architecture you can find throughout the world.
Speaker 1: Like I said earlier, structures made out of mud brick
Speaker 1: are still common throughout North Africa. On North Africa, but
Speaker 1: this one really kind of stood out to us as
Speaker 1: something worth highlighting and just showing what is and was
Speaker 1: possible with mud brick. So, anyway you have a particular favorite,
Speaker 1: or if you've visited a city or an archaeological site
Speaker 1: that features impressive mud brick construction, right in, let us know.
Speaker 1: We'd love to hear from you and we can talk
Speaker 1: about it in a future listener mail episode. Now, as
Speaker 1: for Mud as a whole, our multi part look at Mud,
Speaker 1: I think we're going to go at least one more
Speaker 1: episode here. We're going to come back a little bit
Speaker 1: too mud and warfare. We're going to talk about mud
Speaker 1: volcanoes and who knows what else. There may be another
Speaker 1: mud angle that we don't even know about yet because
Speaker 1: it is yet to emerge through our research, So make
Speaker 1: sure you tune in for that on Tuesday. Imagine a
Speaker 1: reminder that our core episodes of Stuff to Blil Your
Speaker 1: Mind published on Tuesdays and Thursdays, and the Stuff to
Speaker 1: Blil your Mind podcast feed we have let's see listener mails.
Speaker 1: On Mondays, we have short form artifactor Monster Fact on Wednesdays,
Speaker 1: and on Fridays, we set aside most serious concerns to
Speaker 1: just talk about a strange movie on Weird House Cinema.
Speaker 3: Huge thanks to our excellent audio producer JJ Posway. If
Speaker 3: you would like to get in touch with us with
Speaker 3: feedback on this episode or any other, to suggest topic
Speaker 3: for the future, or just to say hello, you can
Speaker 3: email us at contact at stuff to Blow your Mind
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