 We've arrived finally at our keynote for the evening. It's indeed evening where On is. So I'll just introduce him real quick. And then after that, we'll have a discussion where we will be joined by our panelists and also Reinhold Martin who has now rejoined us, who will join us in doing a roundup. So On Barak is a social and cultural historian of science and technology in non-Western settings. He's written three books. The first was On Time, Technology and Temporality in Modern Egypt. Actually, that was the second. The first was Names Without Faces from Polemics to Flirtation in an Islamic chatroom. And the most recent, which is titled Powering Empire, How Cold Made the Middle East and Sparked Global Carbonization. So On is a associate professor at the Department of Middle Eastern and African History at Tel Aviv University. He's been an extremely generous interlocutor for me and for many others in architecture and generosity includes being able to know when to listen to other fields and when not. And it's a great pleasure to have him conclude our today's conference. So On, if you're ready, please join us. Yes, so let me share my screen. And in the meantime, thank you Lucia. Where is it here? Yeah, so thank you Lucia and thank you Forrest and thank you everybody for this really stimulating conversation. And Lucia, you will get your Egyptian time because I was allotted 30 minutes but I will speak something like 35. So let's call it 30 minutes Egyptian time. And for those of you who don't get the joke, I hope it will become clearer as I go on. I will talk today about the connection of concrete failure and fossil fuels. My spiel focuses on coal as an input in concrete production, which hopefully pushes our discussion of concrete beyond its singular materiality towards broader energetic and environmental contexts. And also because very much like concrete coal embodies the tension between fuel or energy on the one hand and fossil or stone on the other. Now, as far as I know, the first reinforced concrete structure built in the Middle East and we have a circular economy here because we're kind of closing the circles from where Nimrod took us off. Is this structure, it's this lighthouse built in Port Said, which was then in Ottoman Egypt. Port Said, of course, is the town in the Mediterranean mouse of the Suez Canal. It was completed just one week before the festive inauguration of the canal in August, 1869. Here we see the canal. The canal, of course, was an engineering wonder. It was based on the largest concentration of mechanical energy in history. And it was an acceleration track for global carbonization. At least this is how I call it, the reversal of decarbonization, the worldwide proliferation of fossil fuels. Now, as a man made channel, it shares much with the man made stone that concerns us today. Both are achievements of modernity, which the horizon of climate collapse colors in a less flattering light. This was true when this talk was supposed to be delivered last month, but it actually goes way beyond the recent blockage of the canal. Actually, the ever given incident throws into sharper relief how things worked in the 19th century. We tend to think of the canal as a single static object, but it was always a moving target. The narrow waterway created the bottleneck through each tacking or zigzagging sale ships could not pass without colliding against the banks. And this promoted the shift of shift to steamers, first to side wheelers, which again damaged themselves against the banks and consequently to ships with rear propellers. So the canal and the ship or the infrastructure and the transportation technology created one another in a feedback cycle. The shift to liners, to steamers sailing in straight lines also promoted point to point navigation and therefore the construction of more lighthouses, more reinforced concrete and so on and so forth. So lighthouses help elucidate the importance of concrete, a substance quickly setting or quickly solidifying and therefore very appropriate for building near or in aquatic environments as an infrastructure for global carbonization. Port Said, for example, did not have in its vicinity stone quarries. It was easier and cheaper to transport cement and steel. By the way, I learned from Lucia in Forest's article that when Hamada developed his carbonation equation, he relied on experiments in different buildings, including the Takao lighthouse near Taipei, another lighthouse built in the 1860s or 1870. At any rate, the Port Said lighthouse guides our path spatially and temporally. Spatially draws attention to the maritime aspects of the spread of coal and concrete, a process usually associated with land. From the sea will proceed to the liminal space of the coast and only then to the interior. And temporarily the 1869 lighthouse allows pushing backwards concrete story which we usually begin half a century later. So this allows retracing the joint spread of coal and concrete to begin the story of beyond concrete in a point before concrete and to kind of enter the Anthropocene, not in the usual acceleration of the hockey sticks after 1945, but in the Second Industrial Revolution. And it also allows attending to time itself, the time of coal and the time of concrete, in the Anthropocene. So I have four points and this is the first one. Discussions of fossil fuels usually assume a rapture with previous driving forces, what is called energy transition. And especially a rapture with muscle energy and human labor. Coal-fired steam engines were assumed to be labor-saving devices. So the steamers passing through the canal, for example, did not require the ample manpower of sailors climbing up and down masts to operate an elaborate system of sails in wind-powered vessels. Of course, they did rely on firemen, stokers, coal heavers, and many, many coal miners, but these workers were less visible. They were underground or in the bellies of engine rooms and less visible and thus easier to ignore. And there was also a new split between extracting the energy and deploying it. This is also true for concrete-making and the coal-fired dredgers, which we see here, built to dig the Suez Canal, to build its embankments, to reclaim land, and also for making concrete blocks are a good case in point. These machines were documented with the relatively new technology of photography in the 19th century in images such as these ones sold in world fairs, almost always without people, or at least without the Egyptian workers that worked on or near them. This tripping away of the human from the technological is surely one way of broadening the discussion of concrete towards energy, the energy of labor power, but it is a more general theme, and I will revisit it later. Many of us already touched on it before. At any rate, missing from these images and from most stories about the canal are the thousands of Corvée laborers who died digging the canal and were buried where they fell, becoming parts of the banks, maybe like in these mafia stories about building concrete bridges in New York City. This invisible dead labor that is not reducible to capital is a feature, not a bug of fossil fuel mechanization. Man-made things, evaporating the human element of making them was what coal-fired steam engines did regularly. Man-made waterways, man-made stones, even man-made ice with coal-fired ice makers, the ice used to resuscitate from heat stroke, workers fainting in the engine rooms of steamers passing through the canal in August when temperatures could reach as high as 70 degrees Celsius in the boiler room, all suggests that concrete was a symptom of coal's ability to quickly transform states of matter. So before we attend to the synergy of coal and concrete, it is important to remember that this nexus depended on other older kinds of power, and these kinds of power were often intensified, not surpassed or made redundant. So this was the first point. And the second point now attends to this synergy. Lucia and Forrest identify a critical feedback cycle, and I quote, concrete carbonation and the rise in the Earth's temperature influence each other acycrocally. Today, the concrete construction industry contributes approximately 5% to 8% of anthropogenic CO2 emissions. Thus, the factor K is dynamic in part because it is affected by the change in the nature of the atmosphere, including the change provoked by all of the accumulated concrete production around the world since 1900. Obviously, most of the submitted CO2 comes from something not directly mentioned, the combustion of fossil fuels. And I wonder if the numbers include sand extraction and metal manufacturing, both also depending on coal and then on oil. Historically, the expansion of the metal industry after the mechanization, after its mechanization in the second half of the 19th century in the related introduction of coal power was a precondition for the popularization of reinforced concrete. But if coal was a precondition for concrete, we seem to have a chicken and egg situation here because if we go back to the sea and to the lighthouses, we realize that before coal could become an available energy source for the local production of concrete, concrete itself was essential in making the infrastructures for shipping coal from the British Isles and elsewhere in Western Europe to the colonies. And in the 20th century for the infrastructures for shipping oil in the other direction. In the 19th century, the steam ship was seen as a railway without a track. A means of transportation requiring frequent stops about once per week roughly, unlike sailboats, which could stay long periods in the open sea. Reinforced concrete facilitated the industrialization of the sea, the carbonization that would in turn bring about its own carbonation. And what we see here are maps of lighthouses in leaps of two centuries each. So the 1850s, the 1870s, the 1890s and 1914. Such infrastructures, calling depots, deep water harbors, customs houses, these lighthouses, the Suez Canal, you name it, in short the localization or the making local of concrete production, the key feature in what made reinforced concrete a standard building technique of the 20th century required the proliferation of its energy source coal and vice versa. So to make my intervention here clear, if Lucia and Forrest give us an atmospheric perspective and a cumulative one, I am trying to complement it with a historical perspective and a maritime one. And indeed, this is how the hydrocarbon economy is represented in the 1860s. This is a famous thematic cartography produced by Charles Joseph Menard, the father of, or the grandfather of infographics, stressing so much stressing the maritime nature of the proliferation of the source of fuel that it has to make these choices like expanding the straits of Gibraltar beyond recognition. Okay, so to my third point, the boom town of Port Said, a city newly built in a place devoid of agriculture or drinkable water, offers a good example to the two previous points. The reliance of coal-based infrastructures on human labor, of those building and later operating the canal, and of the synergy of coal and concrete along the nodes of the system. And it exemplifies also a third project, another process, a third point, the rapid urbanization in coastal plains made possible by the synergy of these powers, human labor, coal, concrete, and several other things like sand. One of the characteristics of global carbonization was the expansion of existing port cities like Alexandria, Jaffa, or Beirut to talk about my own neighborhood and the emergence of new ones like Port Said or Tel Aviv. All these new urban centers were connected, new or vastly expanded urban centers were connected via steamer lines, calling stations, lighthouses, et cetera, to the network of global trade and transportation, as well as to other port cities and to interiors, gradually via railways and roads that are increasingly made from concrete, connecting them to cities like Cairo, Damascus, Jerusalem. Now, Palestinian historian Salim Tamari noticed an interesting phenomenon. Until the second half of the 19th century, Levantine, especially Palestinian coastal towns turned their backs to the sea. They allocated separate mosques to sailors, feared sea breeze and build their houses so that windows and doors turned to the east. And of course, they were surrounded by walls and fortifications meant to repel human and non-human invasions from the sea. Until the 20th century, most of the region's population was not concentrated along the coast, but this is changing rapidly here in the Middle East and globally as Amitav Ghosh noticed. So this is a quote from the Great Derangement. I will let you read it, but the crux of it is that before modernity, people feared the sea after it. They started considering it as prime real estate. Concrete's marriage to coal and oil is an important driver of this process. And Tel Aviv, from which I'm broadcasting, is a good example. The so-called white city and Nimrod also kind of prepared the ground here. The so-called white city was one of the first places in Palestine where reinforced concrete was used in mass and actually the silicate bricks built between the concrete columns and covered in white plasters where what gave the city its nickname. Whereas the lighthouses and maritime environments I alluded to earlier were places reinforced concrete did not push for the adoption of new building styles. In coastal cities, this certainly was the case. White porches, corners without columns, strip windows hugging the corner without being interrupted by a column, et cetera. Now, this is not true at all for Tel Aviv, but certainly true for several of its northern and southern neighbors like Beirut and Alexandria. The process there was pushed by a bombardment from the sea, from steam ships, bombardments that initiated or ignited a de-fortification process. But even when stones of old walls were turned to promenades and cornices, they were supplanted with concrete which was also used for breakwaters and wave dissipating blocks. These made docking as well as seabedding easier. And as a side note in the context of concrete's energetics, it is interesting to mention this feature of absorbing the power of external flows like waves or storms, which is evident in many, many other structures. So the Jaffa Customs House, a famous international-style building built in the 1930s comes to mind. It was built exactly to repel these kinds of storms and waves from hitting the city. At any rate, taller sea-facing concrete buildings were part of a new infatuation with the sea, evident in poetry, painting, even a trend of interior wall and ceiling painting of seascapes even in older houses. I have another one. But the main symptom of this new culture was sea-going and the development of a beach culture, the discovery of the beach as it worked. The new tension, a new tension is born in this moment between two attitudes to sea sand. One is commodifying it as a key input for concrete manufacturing, including the idea that concrete would fulfill the modernist idea of a sand and dust-free city, the kind of Corbusierian city, and turn sand from a problem to a solution by absorbing it into roads and walls. The other ideal or the other stands, sea sand as the soft layer of the beach and later as a depleting substance in need of protection from these very extractive impulses. Tel Aviv, the city that sprang from the sands, emblematizes the Zionist ideal of cladding the holy land with a dress of concrete and cement, as a famous poem puts it. Now, the person who brought these materials to the city after Weiss, in fact, which Imrod presented to us, was Meyer Diesenbos, the first mayor who had a business of importing Portland cement, who founded the company for paving roads and salvaging land, who inaugurated the first Jewish seaport and who was also involved in importing automobiles. He thus personally exemplifies the connection of fossil fuels and concrete and methodologically retracing this nexus might go through following such careers. The fossil fuels and concrete driven turn to the sea, including the carbon footprint of daily commutes to these coastal cities on concrete roads from interiors, the resulting sea level rise, sea acidification, the salination of aquifers, the collapse of the Nile Delta, the damage to agriculture and fisheries, the depletion of sand, among many other environmental repercussions, make it clear that the process of carbonization had other consequences for the world and even for concrete structures way beyond concrete carbonation. Okay, and I come to my fourth and last point. If what I've said so far was meant to rethink concrete in a broader ecology of materials, flows and energy sources, I want to take another step in this direction and suggest that perhaps also the temporality of concrete and the question of its durability or failure, the time oscillating between eternity and the century is not singular to concrete, but rather is informed by this broader ecology of which it is part. Now, we tend to think about the connection between deep geological time and human history and also human science on a diachronical level, in which the human historical time is small scale and recent and it is a time standing on the broad shoulders of the macro time or the macro temporality of deep or ancient time. Viewed like this, Hamada's equation reveals a category error. We thought concrete belong to the latter, the latter temporality, but in fact, it is historical, man-made ephemeral. But while this might very well be true, I want to suggest another perspective, a synchronic one stemming from my thinking about the temporality of coal. To do this, we can go back to 19th century Egypt and we will, but there is a better point of departure, especially in this crowd of an architectural school, Louis Mumford's famous statements from techniques and civilization, the clock, not the steam engine is the key machine of the modern industrial age, which I actually want to put on its head. And to do this, we can start again with a very famous point of departure, the kind of most prominent historical discussion of modern clock discipline. Before steam power spreading the British Isles, the protagonists of P.P. Thompson's 1967 article on time discipline could assert their agency about clock time in the 1820s and 1830s in waterwheel powered mills, but far less so under cold. For these laborers, the clock was a means to fight their employers and insist on implementing the agreed upon time is money equation. This was because the fluctuations and irregularities of water power created tensions and labor unrest. When the river was high, workers were forced to stay at waterwheel powered mills beyond the mandatory 12 hour workday. But steam engines offered capitalists a crucial advantage in these struggles. By the year 1830, these machines were mobile enough to compete with water power, which had bound production to river banks. Mobile generators and portable fuels allowed the mills to be moved to urban centers where workers were abundant and thus replaceable. So against the absent flows of water and work time, the regularity of steam power afforded better exploitation of human work. In the following decades, employers in Europe's periphery in cotton mills in colonial Bombay and in the silk sector in Ottoman Bursa, for example, similarly often chose to ignore the clock in their steam mills, whereas workers on their part fought for more regular clock time shifts, but now often in vain. Steam engines trumped clocks and informed whether, where and how time discipline would be imposed. And as we will now see, also what mechanical time actually meant in different places. So let us examine now the introduction of clock time into the Middle East and its relationship to global carbonization. In the year 1870, the first time tables were published in the Egyptian state railways, a process that went along with the centralization of calling in the railway. The introduction of railway time tables was a consequence of an event a year earlier, with which we're already familiar, the shift of the British India traffic to the Suez Canal after the canal's inauguration in 1869. As a competitor to the canal, the railway connecting Cairo, Alexandria and Port Said had to look for ways to reduce costs and increase efficiency. One of the first targets was calling the largest item in the railway bill, especially in a place like Egypt where fossil fuel was imported at great cost. Until 1870, the different sections of the Egyptian railway operated independently, both technically and administratively. This did not allow centralized registration of coal expenditure or a timetable for the entire railway, due to congestions that disrupted planning and because human calling labor was harder to control and synchronize. Now, a locomotive consumed in the 19th century as much as one-tenth of its daily fuel supply, simply hitting itself to the point that it could produce steam to carry its own weight. Therefore, the steam engine combined thrift in time and coal. The train that lingered in different stations wasted more time and more coal than the train that did not wait. Setting fixed times for passenger pickup drew its logic from this new and synergic nexus of time and fuel. Yet the centralization of, yet if the centralization of coal, of calling and the introduction of unified timetables were interdependent, both these processes could be articulated in multiple ways and not only in the forms that were standardized in Europe. And this was partly because that as long as passengers and goods waited in stations rather than trains waiting for them, delays hardly mattered. In both Europe and the Middle East, the interest of the public, I quote, in regularity, speed, safety, and economy often contradicted the financial goals of railway companies. End of quote. And if this was the case in the quoted parliamentary, British parliamentary report from 1872, a year later, when the coal industry brought about a global Great Depression, railway companies were forced to prioritize coal thrift over the public interests in many places and in many fashions. In Egypt, things were much worse. Under a new debt payment regime resulting from the need to repay building the Suez Canal, the railway was forced to hand over most of its revenue, leaving very little for working expenses. It was also subjected to an international board of directors, making it very difficult to manage. All these caused frequent delays. Delays were directly related to coal saving policies. There were economic reasons for keeping a schedule, but not necessarily keeping to it. Engineers argued that lack of efficiency and punctuality standards should apply in a railway whose, I quote, employees are drawn from the uncivilized population in which years of training must be devoted before they become competent workmen who realize what efficiency means. Means in such a colonial railway, the company would continue to employ cheap labor and shut its eyes to failures and delays until its passengers clamored for better service. End of quote. Now, this hierarchy is quite familiar. European modernity was shot through with a temporal hierarchy that arranged different peoples and civilizations along the developmentalist or evolutionary time era where the British gentleman was the paragon of creation. What I'm trying to clarify here is how this orientalist notion of historical time was translated into timetables and clocks and greatly invigorated under steam which gave it a new lease on life in the modern era and vice versa. How minutes and hours were synchronized or asynchronous with notions of historical time. The resulting Egyptian time was first resisted by Egyptian passengers who were comparing their railway performance standards to what they saw in Europe. But in time, Egyptians started finding benefits in the fact that unlike the alienated, impersonal and rigid temporal standards in industrial Europe, their time was more attuned to interpersonal relationships and laxity. And they began to take pride in the fact that the modernist and capitalist fascination with speed and punctuality was tempered in Egypt by an appreciation of slowness and a synchrony. Lola, this is for you. In many of these critiques, time was not money and even the fossil fuels that animate the time should not be monetized or subjected to the logic of the market. In the canal or the railway or in coal mines in the Ottoman Empire, people rejected the stripping off of the human element from technology or from natural resources. What I just demonstrated for the railway is applicable also for other coal-fired technologies, telegraphs, telephones, tramways and also to other forms of temporality. So not only punctuality, but also synchronicity and speed. The differential nature of time manifested itself on different temporal scales. Exactly what excused operating a railway with more linear standards of punctuality was the position of Egypt in a slower and earlier stage of development on a time arrow whose tip was Western Europe. The colonial encounter created a spectrum of punctualities and speeds that made Egypt lax and lethargic in contrast to the punctual and swift British isles. This was a world view accepted not only in the global North, but also in the global South with least earners bought into it just as much as Europeans did. So in a nutshell, coal fossilized 19th century and earlier racial and orientalist cultural and until then ephemeral notions of time and made them durable as principles of machine operation. Sorry, nowadays we tend to consider the time of coal, not with clocks, but in terms of deep geological time captured in the notion the Anthropocene. We usually think of this relationship in terms of emissions from coal, from coal combustion deposited in the atmosphere as greenhouse gas and through the effects of these emissions like concrete carbonation. But it is important to also note the centrality of the underground and of coal and coal searches in the history that produces this framework, the Anthropocene. While the history of geology and stratigraphy, the division of the earth into distinct layers corresponding to different geological epochs is not exclusively a story of coal. This mineral is absolutely central to the development and spread of this epistemology in the 19th century and onwards when doing stratigraphy was above all yoke to the purpose of mapping the underground for finding the first fossil fuel, the first fossil fuel. The term Anthropocene, the time or epoch of the Anthropos when humanity became a geological force supposes a homogeneity of an abstract humanity. Indeed, the many critiques of the term usually revolve around the problem of the decontextualized or depoliticized Anthropos, the fact that blaming all of humanity in the abstract for a climate collapse, it faces the much greater responsibility of capitalist Westerners, plantation owners, Christians, men or feeling the blank. Far less attention is given to the suffix scene, time in Greek and to the temporal dimension of the Anthropocene framework. Yet alongside the abstract, present-less time of Western geology, there existed other ways of conceptualizing deep time. So to revisit our Ottoman Egyptians and their alternative or even counter-tempos once again in translations of French and British stratigraphy into Arabic and Ottoman Turkish, these people associated stratigraphy with the notion of tabakat or generations of Islamic scholars and thus with intergenerational responsibility. Again, celebrating a time anchored in interpersonal relationships. And they so call as a divine deposit as a gift of God, as a gift of God to be distributed to the community's pious or poor. Ottoman stratigraphy inflects deep time, pluralizes the Anthropocene and opens up the best Chakrabarti's question which Lucia and Forrest repeat of connecting historical and planetary time if not reproducing his answer. In fact, Ottoman temporalities offer an alternative way of thinking about the transformation of humans into a geological force. So how should we think together the measurable time of minutes and hours, the time of centuries of human history or concrete failure and the deep time of geology? This task is critical not only because we suddenly realized the geological time bursts into our own history and present but also because the emergence of humanity as a geological force manifests itself in terms of speed. By becoming a geological force, humanity accelerated and in a sense humanized geological time. Geological processes no longer require millions of years to slowly unfold but can take place in a few decades. By the way, geology itself shifted in the process from what was called uniformitarianism, the notion that nature does not make leaps to gradually include elements of what was once called catastrophism. We are the biblical deluge as it were. And what better example of this than concrete in which humans accelerated processes of rock formation and are suddenly discovering the relative ephemerality of their main rocks. David Wallace Wells recently half-joked in The Uninhabitable Earth that we omitted more greenhouse gases since the airing of Seinfeld than in all prior history. This was long after the scientific consensus shown clearly through the screens erected by the merchants of doubt. We know very well what we're doing. Yet the urgency that should result from this realization is differentially distributed across the globe. And I want to suggest that this too has much to do with the history of carbonization and its hierarchical temporalities. The gap between awareness and action on a global scale is related to the way decarbonization entered geopolitics informed by claims from countries in the global south that they have the right to catch up with the post-industrialized global north before carbon neutrality can be discussed or reached. For example, rather than calling for a global redistribution of existing resources. This is the very developmentalist time arrow forged in the 19th century and in the process of carbonization. But as we have seen, the 19th century was also a time when alternative ways for thinking about time, both quotidian and deep, emerged. So what if along with thinking of humanity as a geological force, we deploy such humanized temporalities and humanized energetics and start thinking of nature or geology as saturated with human ethics, with interpersonal care, with intergenerational responsibility. And the list can probably include Felix's beauty or love. But if we realize that we are still in history in some respect, still in the age of coal and even in the 19th century, that we never stopped being modern but that the key technologies and energies that birthed the modern world animated standardization but also of flexibilization, the logics of the market, that renders energy and matter into flows of capital through say energy as GDP or cap and trade policies but also gave rise to sources of resistance to these logics. So these are just some of the questions that's starting before concrete helping going after it and I look forward to your questions. Thank you. Wonderful, thank you. Oh, and that was an incredible journey where we stopped every so often to fuel up on historical narratives. I'm struck by your taking on Lewis Mumford. I've been known to do that myself. And really questioning where it is that we locate the technological in architecture because by saying it's not the clock, it's not the steamship, it's the clock, he means to point to a more abstract form, he means to elevate his discourse. And of course you point out that that abstraction is in no way distinct from resource extraction. So for this final discussion, I mean, I have tons of questions, but I will instead introduce my colleague, Reinhold Martin, who is a professor of architecture at GSAP as well as the director of the Buell Center and the director of several other things. And he has very kindly agreed to join us for the final discussion. We've asked him to direct some larger thematic questions for let's say 10 minutes or so, make some remarks and then force and I will join back in after 10 minutes to help him and all of us, all of the panelists to have a concluding discussion, concluding of course just for this event, but then many more conversations to come. So Reinhold. I'll just add informally, since I've been informally introducing everybody, that really arriving seven years ago now into the architectural world, Reinhold was my initiation into what the Anthropocene means in architecture, I think at a conference, this was a while ago, so I'm actually very excited to have you here because I've since then appreciated very much so how we talk about Anthropocene in architecture. So thanks for joining us. Thanks, sorry about that, as far as I know that that was true, but here we are. Well, thank you for the opportunity and I want to, I think on behalf of everybody here on the screen and wherever we all are in our networks to thank Anbarak for this wonderful concluding talk. And I basically thought that we could pick up some of the conversations that you all have begun. I apologize for having to step away for a PhD exam midstream that caught many of the conversations and to connect a few dots. And I wanted to do that by going back to the beginning of An's talk to the Suez Canal and to see if there's something, there are some other things there, and I'm just, I'm really honestly just curious what you think that we could pursue to help connect. One is to think about how we think about materials to begin with, whoever that we is, whether we are scholars of architecture, our practitioners, engineers, et cetera, the group that's here or others who might be joining in this conversation. One, the suggestions that have been made throughout and I think you just demonstrated, I think very, very elegantly in a sense, how to do this in four points is to think materials relationally, we could say ecologically in the sense as belonging to and to some extent constituted through their relations with other processes, forces, beings. I'm thinking also about Sophia's brilliant kind of intervention earlier on the internal ecosystem that is concrete. And so to return to that inter-ecosystem, first in the chat, I think first you showed very earlier, you showed the section of a reinforced concrete something with the steel bar and the steel rebar in there to show how carbonation works. And so this is where we go back to Suez. One of the other, you mentioned this in your talk also on that one of the other uses of concrete in the canal was as to make blocks for jetties and breakwaters and so on. Those blocks, as I presume, I don't know for sure, I presume we're not reinforced, which is one of the reasons they could go in the water because you wouldn't have the steel exposed in one way or the other. But the steel nonetheless becomes a kind of limiting and both defining factor for a couple of presenters along the way said, well, when I say concrete, I mean reinforced concrete. And then meanwhile, there were, I think Nimrod showed some examples of blocks. I know there are others, Lola works on this, of masonry units, for example, that are made out of cement and aggregate, et cetera, that we would call concrete. So the steel element reminds us that this thing called concrete internally is composite. And so I was wondering if we follow the steel, whether this takes us back to the clocks in the steam engines again, or we wind up somewhere else. And the steel I had in mind initially was the Bartol di statue of Egypt I think it's called Egypt bearing the light of Asia that was proposed for the mouth of the Suez but was never built in Port Said, but did wind up being built in a kind of modified form here in New York Harbor as a statue of Liberty. And the steel frame of that structure and structures like it, the Eiffel Tower, et cetera, from this period, this sort of matrix of relations that you've laid out. Live on in the different cultures, the design cultures and the intellectual communities that have come together here to discuss materials. And they live on, but maybe a little bit differently. I'm using the metaphor, this vitalist metaphor, live on, et cetera, kind of knowingly. So I'm just, I'm kind of wondering if we begin with a discussion of concrete with the steel and recognize steel as itself a bearer of many of the contradictions, as also belonging to the age of coal that remains with us and so on and kind of is haunted by these enfolded temporalities. Do we wind up any place different? Do we need another conference or do we somehow circle back to put it that way? To where we've been all along? I don't know, so on, what do you think steel? I'm showing everybody the light. Yeah, yeah, there we are. This is the original statue originally intended to report Said and eventually built in modified form right here in New York City. All right, I know this is a wonderful question because one feature of the process that I'm describing and actually one point of frustration for many Egyptians is that everything steel comes from abroad and is assembled in situ. So if we start with the steel, concrete is not a local material. So, and I think that makes a tremendous difference. And concrete has this character of being local but being also Western requiring expertise from Europe or elsewhere. So it's kind of dual purpose of being both local and not exactly has to do with its composite nature and the wedding of cement and steel. So I think this is really a way to inflect the conversation in fascinating ways. Yeah, I mean, I guess I had in mind also with the steam ships, the railroads, all of which belong to this ecology of steel that as you showed up with concrete in turn intersects with and depends upon the deep history of coal and its modern geographies in ways that to some extent do map onto one another like in what you said about the railroads. And in other ways don't. And then to kind of bring it fast forward because I don't remember offhand the numbers as far as maybe you remember like steel production contributes some quite comparable degree of CO2 these days. And for in the building economies that we're talking about in contemporary cities, for example, it had been the case and I think it varies case to case that labor costs, one very deterministic but I think probably not entirely inaccurate reason or argument that's often cited for the predominance of concrete construction in the global south and under conditions of so-called development, et cetera is the availability of relatively inexpensive or cheaper or even in the case of the Canal Corvée labor whereas steel is made in factories and shipped and the sort of division of labor operates differently along the networks of steel. And in cities like New York, this was for a long time, the reason that was said, why is New York a city of steel skyscrapers? Well, because of this division of labor, this has changed and even sometimes I appealed to the engineers here for a second, I've known of projects in which the material is changed sort of midstream. They designed a skyscraper initially for steel and the construction cost, labor cost, that equation doing labor, material and transportation changes and suddenly you have a steel building rather than a concrete one or vice versa. The Trump Tower, by the way, is a concrete building, I believe even though it looks like it should be steel. So that economy, that exchangeability, I guess was what I'm getting at also occurs under specific political economic, geographic situated sort of conditions. What doesn't seem to change much is the carbon emissions. So I think this is where your point is taken again that underneath or within and kind of in the seams of all of this is the Anthropocene. So I don't know, I didn't want to dwell too much on that but it seemed, I don't know if anybody else has any. Oh, Reinhold, I was going to say, it's always struck to me that there's an economy of visibility and this is very local to the history of architecture where the 19th century is supposed to have made steel eminently visible. It became this visible supplement to stone in the 19th century, Bosar architecture of La Bruste, et cetera. And then gets subsumed and then gets sort of debated and shaped into forms which are supposed to be properly modern, let's say. As opposed to concrete, whose story is that it was there all along masquerading a stone and only, and is revealed to have been modern all along or something like that, as opposed to steel history, which is, or irons, it's really metal, which is, was trying to show itself off as being a slight modification of Bosar architecture and had to be radically transformed by engineers, had to go outside of architecture in a sense. Does that make sense? Yeah, yeah. In fact, what I had in my, with the jetties and so on is that under those conditions, what is concrete? It's not stone. Otherwise, if there was stone available, it would have been stone. Whereas under this in the skyscrapers, what is concrete? It's not steel. Yeah, yeah. I very much owns bringing up of concrete already as a repair material. I mean, this goes also to Lola. I was like, couldn't you add a little bit of concrete? Yes, it was there all along and it didn't need to be featured heroically even in the lighthouse. That it was, there is an ingredient of repair from the beginning. Yeah, and in the context of these long time scales we've arrived at now at the end, right? I think the feedback loops of the materials have come to the fore and things like steel now are mostly talked about in the context of what percentage of your steel is recycled when you start a project. And that ends up playing out in the dynamics of calculating what your decisions are in a strange and new way, I would argue today, like particularly in the competition between new massive timber buildings versus steel versus concrete. Like there's a new player in the game and that's largely because the equations maybe have shifted slightly though, I would say not very precisely and that lack of precision maybe comes from exactly where it sort of ended on this geological, like how do we bring in geological timescale impacts of what we represent, what you showed in the wonderful image at the end and what Felix showed at the beginning of all the curves of things that are changing rapidly, but like to us sitting here in the next 10 minutes it's still not rapid enough to really bring into the equation that the person at the project site is calculating how much does this building going to cost over the next few years. And I think that time scale is the one that's yet to fold in effectively, I guess, to make those decisions between not just steel and concrete but also just sort of bringing in the other externalities, many of which we I think had very good points made today about, but I'm still at a loss to whether those complexities can really come together. I have just one more quick question. I see Sophia has a question as well. I just on the time scale question for on, and then we can go to Sophia. I just wanted to add, since this was a, in terms of circling back to the beginning and clearly the three of you are in sync in terms of puritization, the hundred year timeframe is a meaningful one, but you did refer and others did to what's sometimes called the Great Acceleration and other moments of change, of a temporal speeding up and maybe they're even slowing moments of slowing down that mean something to us both historically and in terms of the urgencies of the present. So is there something to be said? Okay, if we go back to the hundred year timeframe about prioritizing that vis-a-vis concrete and then over the Great Acceleration, for example, or should these be seen in some sort of rhythm or something like that? Yeah, can I add to that? I'll just piggyback into that question for on. You seem, your argument reminded me of arguments by historians of like Christophe Bonet's argument, for example, that there's incredible hubris to calling the Anthropocene. And I mean, you've made this argument in print too. Of naming a certain age as the human age and that we should not resort to geological times, not resort to that, to two different temporalities because it's narcissistic. My sense is that in architecture, this has the effect, it's also narcissistic, of course, but in a certain sense allows architects to self-anthropologize and to, it's meant as a critical gesture that says look at what you will build in millennia, it will have this effect. So I think architecture considers itself a uniquely sort of impactful discipline on the earth or something like that. So are you saying that we should not, are you recommending we don't refer to alternate, let's say geological temporalities or are you simply trying to rescue, let's say 19th century temporalities such as the Ottoman time, which is also 19th century, but more sociable or more attuned to social distortions. Yeah, so to all of these questions, you know, part of the literature and the Anthropocene is organized around a competition for the starting point, the industrial revolution, post war, the discovery of fire, the agricultural revolution, you name it, but I think it's much more useful if the Anthropocene or whatever we want to call it is a hyper object in Timothy Morton's phrase, then it's something that has multiple points of entry and it is not something that is organized around a single beginning. So I think that I'm not trying to move away from or to do away with the time of geology, I'm trying to kind of critique it from within and inflect it from within and synchronize what is kind of being purely diachronic to show that there are various kind of inflections of deep time of geology. And I think also practically or politically, this is now the Anthropocene is the only game in town it doesn't make sense to replace it with the capital or scene or plantation or scene or whatever scene, but rather to pluralize it and to kind of absorb all of these things inside it also as a way to kind of promote what you are doing to kind of bridge between scientists, even if they are geologists and humanists or people kind of thinking of politics and politics is a human thing. Fantastic, great. Great, yes. So Sofia had your hand up, I don't... Yeah, this has been tremendously fascinating and one of the things I was thinking about following on Ones talk is so a couple of kind of theories of temporality have been floating around these conversations over the course of the day. I know Chakrabarty's been brought up a few times and I was thinking about the way in which Chakrabarty talks about how the Anthropocene is this moment in which humans have intervened into or interpenetrated into geological history and he actually uses a geological metaphor in talking about this, right? So Chakrabarty says that we've overcome this rifting or faulting between human time and deep time and I find this incredibly problematic because I don't think that there really was a rift in the first place. But one of the things that I was thinking about following on what Ones just said is that perhaps a better model for this relationship between the time of human experience and the time of geological periodization or geological epics comes from someone that Luchian forest site, right? Ryan Hart Kosele, who talks about what he calls stratigraphic time, you know? And the notion that natural history is something that gets interbedded with human history, right? And so your reference of the 100 years as this moment in which we tried to naturalize the century as a unit seems important to that issue as well now. Yeah, exactly. Yeah, I mean, I think it speaks to the rate of change from. Yeah. No, and I can add to that that, you know, Koselec in many places in Noizite and in other, for example, take this famous kind of description of what happens to revolution which enters politics as it kind of exits the circulation of seasons. But again, like with the tree that Luchia started us off with, it's a post-seasonal in or it could be a post-natural temporality also in the sense of extending rather than just breaking with. So I think this kind of Koselecian time and treatment of time is very fruitful and we should all kind of revisit and excavate his writings for these bridges between the natural, you know, the human and the planetary which Dipesh Shackabarti as synchronizes in an unfortunate way. One thing that's interesting is that we've seen several examples so far today of an architecture which wants which calls for an interpretation of accumulation of material accumulation. Certainly this was true of Ateya's shell buildings which are shells and therefore appropriate for just storage of piles of stuff, but you don't need an architecture. If you need to store piles of stuff, you can either make a cylinder where it adopts the volume or you could just make a pile and you put a roof on top and that this was very quickly imported into the same kind of diagram as the geology but it wasn't geology, it was the market. It was the fluctuation of the price of grain. So there's ways in which I think architecture gets at least in the 100 year period in which we're describing things. The architecture of reinforced concrete gets put in the service of either visualizing accumulative temporality or not. And I think Reinhold, this would make it very different from steel. Like steel would be the standard object that gets multiplied and sent and is self-similar everywhere it goes as opposed to accepting the case of the Statue of Liberty of course, which is not self-similar. But in the case of concrete, you really give the designer the opportunity to either represent a cumulative notion of time one where time, temporal passage is represented as material accretion or not. But this would seem to make it the last 100 years, very different let's say than the years before. And it strikes me that this also makes it very different from the Anthropocene where we're, so that would be, I guess I would want to know from own, do we let that enter the sheer material visualization of the temporal accumulation? Do we let that enter or be one of the entry points into the Anthropocene or do we just say, well, this is a sort of ideological scrim that architects are telling themselves in order to represent dominant temporal modes. Are those necessarily separate? Okay, Tushé, good, yes. So the architectural indices of entry point, architects are designing entry points into the Anthropocene. Yeah, you know, one of the things, the reason I was asking about the so-called grid acceleration though, I know many reasons, but one would be to think about how we think about puritization. I think this conversation is helping in that, including the discussion you just were having, Sophia and on about Kasalic, rather than as, compartmentalization or some sort of mechanical stepping from one time zone to another in a way. And more like a kind of pulsation or of rates of change, of stasis, of force. So for example, in the now canonical, early scientific articles that define these things like Anthropocene and grid acceleration, I think it's in the Stefan Kritsen literature somewhere, I forget. They have all these graphs, it's like 16 or 18 little graphs, they all look the same, we all go like this. And many of them make a lot of sense and correlate in terms of, you know, deforestation or whatever, I mean, ecosystem loss, et cetera. But then one of them has to do with the number of McDonald's that there are in the world. And it's, first of all, it's striking to me, this is, and they flip side of the discussion about beauty the other day at the other panel. The degree to which something that seems utterly extrinsic and extra scientific in a sense to this conversation is necessary or at least judge a useful placeholder for something else that is not captured in the other graphs that are defined, other more logical correlations. Now, it's not to say this isn't logical, but the logic is different. So that's, it's kind of in that spirit that I'm kind of asking about the steel concrete dialectic that if we, with the 100 years and with the pulsation, you know, what does it look the same from that point of view when you discuss other, when this whole discussion is refracted through other material complexes? Is the common denominator still gonna be cold? Probably in most cases. Does it matter if there's some sort of subtle inflection in terms of the energetics and or the natural history of these materials, you know, for the bigger picture that we're collectively trying to paint? I don't know, Lucia, yours? Yeah, that's a great point. Just thinking, I think the McDonald's is the steel model. It's a consumptive model. The reason they have that probably. Yeah, it stands for tied to consumption, to tie to an idea that we all eat the same thing and so indeed the idea that steel goes everywhere paints a picture of architects and designers as consumers of a product that comes to them as opposed to the concrete mode, which is one where, although we have just been describing for now two conferences that it does take an industry to make the cement and that's extractive and it attracts monopoly and everything. There is a market for it, there's control. Still the person building their concrete home at home with steel found on the ground considers themselves not to be a consumer but to be a builder of something. So those would seem like when I was thinking that the tree model is being subsumed under this or whether it's, you know, whether, as you said, if concrete is an extension of the tree, the tree model that we would have to have now is that any tree that you take to build something you have to imagine that you're gonna, somebody's gonna plant another tree in order for the exchange to work. So to me, the concrete extension works slightly better than the, like to me, Reinhold the steel is the McDonald's. Yeah, yeah. But I wanna add, I wanna do to McDonald's what I tried to do to time of coal and concrete because I think this kind of infatuation with McDonald's has its roots in the Benjamin Barber kind of a world versus Jihad. Yeah, Mcworld, right, right. Which your colleague, Timothy Mitchell, inflected with the notion of McJihad. In other words, you know, McDonald's branches couldn't be more different in different places in the world. In many of them, you can buy meat. The reason they would be on one of these hockey sticks. So I think we need to kind of pluralize McDonald's as much as we, as, you know, exactly like we need to pluralize concrete and coal and so on and so forth. And the other thing, the other thought about what you're saying Reinhold about, about the great acceleration. And that's why I mentioned this joke by David Wallace Wells. Maybe 1945 isn't late enough. Maybe we need to kind of look at what's happening in the 1990s. So we can't really choose. It's also a question of responsibility, right? We can't kind of excuse from responsibility those political actors who would find it more comfortable to begin the conversation or the entropocene in one point or the other. It's all of the above, I think. Well, one way to think about that is that the tendency, especially in our field, the architecture and it's a light feels to want to quantify things that have to do with the earth, you know, deforestation to quantify that and to tie that to a periodization is very strong. And we've been doing it now. We're doing it in our paper and Reinhold just did it with steel. And it sounds like you're calling in a way owned for a quantification of just more human phenomena, which would inevitably lead to the diversification. And even the theorists of the great acceleration have done this. They have said, well, there was a great acceleration, although you can still find places in which you would have made your own, you know, made and had your own breakfast or something like that. So it sounds like just the sheer emphasis on the human reception of these material phenomena would do that. I think there's still one comment. Well, I was just gonna say in the, there are humans and there are humans and then in the spirit of differentiation and, you know, we wanna begin by recognizing with that differentiation comes struggle. I read that to be, you know, more than between the lines of your point about labor in the very beginning there. So what's interesting to me about how we periodize, this is a little bit analogous to the Kaselek. What Kaselek does, a decidedly anti-revolutionary historian, you know, this is somebody who's writing in a sense against those historiographical traditions that want to, in one way or another, remember the revolution even if it's, you know, in its failures, the war, you know, another name for the great acceleration, especially with architectural historians because reconstruction after the Second World War is so important in spreading, you know, and kind of the growth of various modernist idioms and so on, that we could just call it post-war. And that is, would, is in some sense a Mumfordian characterization as well to the extent that Mumford is a kind of historian or thinker who spends time with the implements of war as to some extent generative or productive of human relations as well as reflective of these kinds of struggles. And so if we replace the struggles, or supplement, let's not say replace, but supplement the conflicts that come with Anthropocene thinking, which I think, you know, I don't know if we're agreeing on this, but my sense is that Chakravarti shies away a little bit from this when he drifts towards natural history. He leaves behind some subaltern studies, good solid Gramscian, you know, kind of counter hegemonic thinking is to ask, you know, how does what we call post-war look different when thought of as in the one hand as continuous with this 100 year history that you're trying to lay out. It's just war by other means. In other words, concrete is war by other means after the war, when you're counting the carbon and or discontinuous in terms of what, you know, either accelerates and or changes in other ways. So because this is for historians, especially for those of us who deal with the built environment, a regular, it's almost a cliche that the various wars, you know, interrupt construction and they produce new technologies and therefore. Yeah, but there are events in moments maybe relative to the material, to the plots, the many plots of the accelerations. Most of those accelerations don't register these individual events or revolutions. And so the question is, how does something that spans the century in active revolution when it's, although seemingly a great acceleration relatively slow compared to most things that cause revolutions, I would argue. But that, I guess the context I said in, what's the hand? I'm just following you guys leading. If anyone wants to meanwhile respond to your question in the chat. No, I was just gonna frame that as a question in the context of how do we situate that in the modern evolution of, well, the great acceleration is one term, but the positivist framework of sustainability and the 1990 Earth Summit and how we've tried to create, you know, Donnella Meadows and systems theory about how can we model all these complex things and are there ways to be reactive to all these dynamics of dynamics? And part of me says no, but I think rhetorically we have to say, yes, I guess. I mean, that's what I'm wondering in the context of the different time frames on you've presented whether we have a strong weight to claim there should be a change in a shift in thinking, right? Because generally I don't see where in history we have made a significant change in behavior due to such a slow and incessant shift in the underlying driving mechanisms that would cause the change, I guess. Like even for coal, like the fact that coal is still used, right? There's so many reasons it shouldn't be and you've plotted out this wonderful history of how it continues to be. And I think that within that hybridizing that with these redefining time scales and recognizing what is a rapid rate of change, I think is where there may be a pathway to a different kind of argumentation, but I don't know if you agree. I mean, I don't have an answer. I have a way to kind of make the story more complex because I think what the temporal conundrum that we're including to is also relevant to how we think of energy. So coal is on the rise in total sums of the mission, but on the rapid decline as kind of as part of the pie. So I think the abstraction of energy and this kind of dual nature of how we think of energy and the introduction of statistics to our thinking of energy is very similar to what, to how we think of time. And I think this is one of the ways that or one of the junctions that your concrete is kind of raising. That's very helpful actually. One of the most humbling parts of this project for me and working with Forrest has been to notice how much the narratives given by popular history make it into the presentations of scientists, scientists who are quantifying time in a legitimately precise way, even whether they're talking about millennia or whether they're talking about their experimental increments. Inevitably, some large scale periodization that a historian has made makes it into the introductory paragraph. Since the dawn of time pyramids have done this and as the architectural historian who is taught to disclaim that they are not a scientist, that they only are telling narratives and that insofar as they talk about centuries, those are not exactly a hundred years of course. It's a very humbling problem to encounter. How does one change the way one tells a history when faced with historians with scientists who would very gladly change how they talk about periodization and correlate their own timekeeping, very precise timekeeping to some larger narrative. So the way you just described it on was very helpful, which was that it seems like accounting and risk and energy go together. And this is the story of 100 years of concrete is of course not really about 100 years. It's not really about geolateral time. It's about the advent of this probabilization in all forms of ways in timekeeping and in also construction. Let's say just dumb it down super to the most level. I see- Yeah, exactly. And as an engineer, I'll just confirm that I would be 100% as a believer in time driving everything, but it's exactly that kind of narrative to rethink how the steam engine and energy is actually feeding back and changing that where perspective can help technical thinkers also reimagine what the problem really they're working on is and what the driving forces are. I think that's equally important to the historian recognizing sort of how technologists are leveraging history itself. I mean, I think that's what, you know, Lewis Mumford when he said the clock is what matters, he's trying to account for probability. He's trying to account for those managers who are using clocks to decide whether how the built environment is made. I think your retort, which is actually the steam engine did that work. The steam engine coal did that work, but it's still a time of temporal probabilization. I see that Sophia has written in the chat. Yeah, yeah. Meritization is a parallel process in geological timelines and sociocultural divisions. Yes, excellent. Okay, so I will invite our panelists. Sophia, that will count as your parting thought. Or feel free to jump on with another one, everybody. If you want to give live an alternate parting thought, and I want to- The marathon Zoom is coming close to- Thank you all so much for your amazing talk and for, you know, being such a good intellectual companion all this time in this particular instance. And thank you to all of our panelists. Thank you, Reinhold, for joining us in the concluding. And thank you to everybody who's staying at plates to be with us. So any concluding thoughts from our participants, we should let people go. It's Friday. Really, it's very hard to be part of a conference where the modes of research and of data presentation are so different and people are coming from such different places, but I thought that we did have some threads. So, I don't know, I'm pretty pleased. At least with the number of questions that are unresolved, that cohere as unresolved questions. Please just jump in if you have any parting thoughts. Yeah, any thoughts. But I'm sure everybody doesn't want to start off on the debate. Or we could just thank you all. Yes, we could just thank you. So, we'll give a moment of silence in case somebody has a really burning thought they want to. And it better be burning. Besides happy Friday. All right, in the afternoon. Well, in that case, I get to thank Lucia for putting up with me, I guess. And to all of you for also enduring the long Friday presentations. It was wonderful. Again, can't imagine it coming together better. And everybody did a wonderful job of responding to each other. So, thank you so much. Yeah, thank you so much. We really, now we have to rewrite the paper. We can't take the paper away. Also to the audience, our paper's coming out in a volume edited by aggregates, which is titled Evidence, Narrative, and Architectural History. Unfortunately, it won't have any of the changes that we would make now that we know. Oh, yes. Particularly after presenting it this morning, we're realizing that we're re-saying some of the things that we learned needed to be modified more from the last conference. But we appreciate everybody's comments and responses to some of the points we were trying to bring forward. This is the privilege of having an ongoing project. And we, so we will, there will be a YouTube video of this event. And then we will, we also have a link to the video, which was the Princeton event. And we hope to reconnect with everybody on the other side. Thank you and have a good Friday afternoon or night. I hope. Yes. I think it's late in the afternoon. And don't forget your mothers and to Lola who's, you know, braving this about to become a mother. Happy Mother's Day to all the mothers out there.