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Video transcript

we're standing in the Piazza the square in front of the Pantheon this is the best preserved ancient Roman monument and yet look at the sense of age look at the weathering good the way in which its history is revealed through its surface it's been attacked its original bronze fittings have been ripped off look at the numerous holes for instance in the pediment the tale of all of the different purposes that this building has been put to originally a temple to the gods then sanctified and made into a church now of course it's also a major tourist attraction this is a building that has had just a tremendously complex history and you can see it all over its surface for seeing it very differently than anyone in antiquity would have seen it in fact we're standing many feet higher than we would have been in the ancient world Rome accumulated elevation from the debris of history once you would have stepped up to the porch of the Pantheon now we actually lie down hill and the space in front of the Pantheon was framed by colonnade the colonnade from the other buildings that would have originally surrounded this building would have obscured the barrel on the side and so that we would have only seen this very traditional temple front exactly it would have been something very familiar and a surprise was what happened as you approached the threshold I have to tell you that I'm absolutely in love with those massive columns they're supported by these enormous marble bases they rise up unarticulated without any fluting and then end in these massive fragments of what were the originally marble Corinthian capitals these are monoliths they're single pieces of stone unlike Greek columns they were not segmented they were not cut and they were imported from Egypt which was symbolic of Rome's power over most of the Mediterranean under the Emperor Hadrian who was responsible for the construction of this building so let's go in let's go under the porch let's go through those massive bronze doors we just walked in the strictly rectilinear porch and then the space opens up opens up into this vast circular space the width of the building in the height of the building completely fills my field of vision and it is in a sense an expression of the limits of my sight unlike our Basilica this is a radial building that is to say that it has a central point and radiates outward from that central point but what's fascinating about this building is it's not a traditional radial structure in that the point would be on the floor the central point its focus is midway between the floor and the ceiling and midway between its walls it is large enough and geometrically perfect enough to accommodate a perfect sphere and as soon as you walk in you notice that there's a kind of obsession with circles with rectangles with squares with those kinds of perfect geometrical shapes this is a structure that is concerned with the ideal geometries but it also locates our place within those geometries but the experience of being in this space is anything but static no it's really dynamic in fact and one of the causes of that is if we move our eye up the columns you can see that they're beautifully aligned with the frieze of false windows that are just above them but then all of that does not align with the dome that's right they don't align with the coffers that we see in the dome what that does is creates this feeling that the barrel that the dome rests on is independent from the dome and almost makes it feel as though the dome could rotate that complex visual relationship between the dome and the decorative structures in the barrel remind us that this actual structural system here is dependent on concrete and not these decorative columns that we see on the interior exactly there's thick thick barrel of concrete that supports the dump because the dome pushes down and out Roman architects had to think about how to support the weight and pressure of the dome and one of the things that's doing that are the thick concrete walls of the barrel you know the Romans had really perfected concrete and this is one of the buildings that shows what was possible this is shaping space because concrete could be continuous it could be built upward continuously with wooden forms which would then be removed and could then open this space up in a way that post and lintel architecture never could so concrete could be laid onto a wooden support or mold and could be shaped in a way that you can't do with post and lintel architecture well what what it does is it allows for this vast open uninterrupted space we walk into the space and we feel freed we are given a tremendous amount of freedom in terms of how we move and how we see through this space because of the Roman use of concrete the idea that architecture could be something that shaped space and that could have a different kind of relationship to the viewer it is even now in the 21st century awesome the Emperor Hadrian under whose direction his building was constructed apparently loved the building and loved to actually have visitors come to him here one can imagine him even in the back apse opposite the entrance the Pantheon originally contained sculptures of the Gods the deified Emperor's we think it really was about the divine it was about the earthly sphere meeting the heavenly sphere and also in some way about human perception look how rich the surface is and there would have been much more in antiquity when the coffers probably had gilded rose as we look at the drum we see colored marble we see purples and oranges and blues remember these marbles are taken from around the Roman Empire so this is really an expression of Hadrian's wealth and Hadrian's power this is the empire being able to reach across the globe to draw in these precious materials perhaps the most exciting part of this space is the oculus because it almost seems to defy reason how could there be a home in the center of that dome it doesn't make sense well it's the only light that comes into this space with the exception of some light wells in some of the recessed areas and of course the grill just above the door and the door itself there is one great window and my students for years have asked is there glass and of course the answer is no when it rains the floor gets wet the perfect circle of that oculus the perfect circle of the dome the oculus is critical in the issues that you had raised before this is a building that in some way is a reflection of the movement of the heavens and what happens is light moves into this space from the Sun it projects off in a very sharp circle on the dome and moves across the floor of the building as the Sun moves across the sky and then eventually creeps up the other side of the dome and so this entire building functions in some ways almost like a sundial it makes visible the movements of the heavens and makes them manifest here on earth we've been talking about this building as a great monument of the ancient world but it was admired and copied in the Renaissance and in fact is perhaps the most influential building in architecture in the Renaissance and in the modern era we think about all of the different architects that have referenced this building I'm looking down at the floors and the geometry that you spoke of the circles and the squares I'm thinking about the pavement in front of the Guggenheim Museum on Fifth Avenue in New York actually once you know the path yeah you begin to see copies of it and pieces of it everywhere it's true the dome especially is perhaps the most copied element especially with the oculus you can see that for instance in the National Gallery in Washington you can see it in almost every neoclassical building in Europe and North America but before we leave I'd love to go and pay homage to Raphael who's buried just over there you