btes 2017

June 12, 2017 § Leave a comment

DMAC 01That was the view from the final evening of BTES 2017, the biannual meeting of the Building Technology Educators’ Society.  Des Moines hosted it, the first time it’s been in ‘flyover country,’ and I enjoyed the chance to co-chair it with rock star colleagues Rob Whitehead and Shelby Doyle.  Over 70 faculty and students trekked to Iowa, and we heard papers ranging from studio and design-build pedagogy to solar analysis of historic buildings and more speculative thoughts on how Poetics and Pragmatism, the themes of the conference, relate to one another.

BNIM Des Moines principal Rod Kruse and ARUP principal Fiona Cousins both gave excellent keynotes on their practices and how they relate to these ideas, and I was honored to join them to give the introductory keynote.  Given the theme, and the fact that we had a large group who had, in the usual way, either just flown over or driven through my adopted state, I thought it was worth giving a bit of an overview of the state’s history and architecture, but also to probe a bit more deeply into what it means to work here, and how the unique history of the place has given us both traditions and writers who offer provocative perspectives on how the physical world and our lives within it interact.  This isn’t the sort of thing that has a natural outlet for publication, so for the record (and since I’ve been working on it for the last month instead of posting…), I thought it would go nicely on architecturefarm.  It follows in two parts [here and here] in the next two posts.

palladian building code

May 7, 2017 § Leave a comment

IMG_6439Reading Palladio on the flight home (because, really, why wouldn’t you).  His Quattro Libri have been excerpted to no end, and there are familiar passages that most course readers focus on (mine included).  But in the bits that usually get passed over, specifically the chapter with the fetching title of “Of stairs, and the various kinds of them; and of the number and size of the steps,” there’s this, which could have been pulled right from the International Building Code:

THE ſteps ought not to be made higher than ſix inches of a foot; and if they are made lower, particularly in long and continued ſtairs, it will make them the more eaſy, because in riſing one’s ſelf the foot will be leſs tired ; but they muſt never be made lower than four inches: the breadth of the ſteps ought not to be made leſs than one foot, nor more than one and a half.

THE antients obſerved to make the ſteps uneven in number, that beginning to go up with the right foot, one might end with the ſame ; which they look’d upon as a good omen, and of greater devotion when they entered the temple: The number of ſteps is not to exceed eleven, or thirteen at moſt, before you make a floor or reſting-place, that the weak and weary may find where to reſt themſelves, if obliged to go up higher, and be able more eaſily to ſtop any thing that ſhould happen to fall from above.

OK, not so much about the uneven steps, but with some minor adjustments to take into account the difference between a Vicenzan foot and an Imperial one, thirteen steps is still, five hundred years later, the maximum number of risers between landings for precisely those reasons; and he’s got the tread to riser ratio right in the sweet spot as well.

castelvecchio

May 6, 2017 § 1 Comment

castelvecchio 04Nine years ago, when I was teaching in Iowa State’s Rome program with my colleague Pete Gochè, we took half of the students up to this part of Italy to see Vicenza and Verona.  Interspersed with Palladio, the other designer you go see here is Carlo Scarpa, who was based in Venice and, like Palladio, did most of his work in the immediate region.  His best-known masterpiece, the Brion Cemetery, is a drive outside of Vicenza, but the Castelvecchio museum in Verona, built into one of these Italian defensive structures that has an impossibly layered and complex history, is just as awe-inspiring.  Like Brion ,Castelvecchio took Scarpa years to complete, and it’s also a composition that’s based on total sensory immersion.  Pete and I were thinking on the fly when we took students around, but in talking through what we were seeing we sort of came to the conclusion that Palladio and Scarpa were perfect foils for one another.  Palladio’s buildings are based on an overall harmonic composition, in which the mathematics of the scheme trickle down and inform all of the details.  Scarpa’s begin with the details, with a very specific sensory experience of light, or touch, or with a focused idea about a material or how two elements come together.  His designs then work outward from those.  I remember looking at his work for the first time as an undergrad and just not getting it–his plans are often mysteriously composed, without any visible sense of composition.  But the first time I stood in the sculpture galleries of Castelvecchio, I remember feeling like there was something for the eye to rest on absolutely everywhere.  The satisfactions of this building come in a thousand different moments, while those of, say, Villa Rotonda come from walking around it, seeing it in perspective and starting to understand how the entire thing holds together as a self-contained piece.  Palladio built architectural fugues, Scarpa built architectural etudes.

castelvecchio 03In our first-year studio this semester, Andrew Gleeson and I talked a lot about architectural rhetoric, how every design problem boils down to an argument about something–materials, composition, light, experience, something.  Scarpa layers these arguments on top of one another, showing in a typical handrail detail, for instance, how the warm wood of the rail itself contrasts with the raw, cold edges of its steel support and with the cold, rough surfaces of the local Veronese stone behind it.  These moments are virtuosic–he’s clearly showing off–but they’re also instructive.  You know exactly where to put your hand, and you see instinctively how the rail is put together.  They’re also, of course, incredibly well composed.  Those elements could go together in a thousand different ways, but much of Scarpa’s notoriously slow process involved iterations, even on the job site, moving and re-composing until the detail not only was right, but also looked right.

castelvecchio 02I’m sure Palladio showed up on a job site or two and changed things around, but the rhetoric of his designs was almost entirely Platonic.  If you get the math right, his plans argue, then the details are inevitable.  This is what Jefferson complained about when designing his Palladian tribute, Monticello–when he changed the size of a window on one side of the house, the door frames on another had to change as well, because the basic argument of Palladian classicism is that the entire building is an integral system.  Scarpa’s rhetoric is exactly the opposite–the entire building is built up in literally hundreds of individual experiences that may be orchestrated, but that don’t depend upon one another in the abstract for their meaning.  Rather, they relate to one another in the way our senses are set up or prepared.  Lining up doorways in a Palladian villa is something you do because the rules of the composition tell you to do it, whereas lining up doorways for Scarpa is a way of hinting to your eyes about what they’re about to experience.

castelvecchio 01There are all sorts of dialogues in Castelvecchio–light vs. dark, new vs. old, honed vs. rough, etc., etc.  And the entire project set up a handful of important principles for historic preservation.  Everywhere the original fabric is treated as an artifact, and Scarpa’s interventions very carefully set themselves off from anything antique.  Concrete, iron, and stone are detailed with healthy shadow gaps that make it apparent what’s been added to the existing building, and the complex layering of old materials is presented at face value, which makes for amazing, lush backdrops like the one above, in the ‘knuckle’ between the sculpture and painting wings where you literally cross a bridge between the two buildings and are confronted with an array of materials and objects–including the heraldic statue with its own stairway and viewing platform, a little architectural gift that provides a break from the slew of galleries before and after.

A fine final jaunt on what’s been a full and inspiring five weeks…

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palladio

May 4, 2017 § 2 Comments

palladio“Vicenza, a city of no very large circumference, but full of moſt noble intellects, and abounding ſufficiently with riches ; and where I had firſt an opportunity to practiſe what I now publiſh for common utility, where a great number of very beautiful fabricks are to be ſeen…”

–Palladio, Andrea. The Four Books of Architecture (Dover Architecture) (Kindle Locations 574-576). Dover Publications. Kindle Edition.

Finishing up my time in Italy with some outright tourism, in particular getting up north to Vicenza, which is to Palladio what Oak Park is to Wright–an outdoor museum, and a lovely town to spend a couple of days.

Palladio is something of an obsession.  Teaching Renaissance architecture last semester, and coming back to it this semester in Big and Tall, there’s a moment in his career of synthesis, where the linguistic project of applying Roman architectural “quotes” and the systematic project of finding a deeper and richer architectural order came together into something that seems very much of the Renaissance and of the Enlightenment.  His treatise is almost entirely practical advice–very little hints at the complex system of musical ratios and proportions he employed to make spaces and elevations that feel literally ‘composed.’  But in blending much of the same practical and philological advice that Alberti and others had already published in his own work, Palladio added a deep rigor to his designs that seems to look ahead to the more complex mathematics of the 17th century.

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Some of this, I think, comes from a near-perfect architectural education.  Until he was 30, Palladio was a stonemason–apparently a good one, but nonetheless a craftsman.  While working for the Vicenzan humanist Gian Giorgio Trissino, probably on the Villa Trissino in Cricoli (above, seen from across a rather jogger-unfriendly traffic circle), Palladio struck up a dialogue with his client and began a twelve-year friendship during which Trissino mentored him and brought him to Rome for the first time to study ancient and (then) modern architecture.  After Trissino’s death, Palladio enjoyed the support of the Barbaro family, who were his gateway into Vicenzan and Venetian society; he became something of the court architect for wealthy families in the Veneto, designing palazzos, villas, and eventually chapels and churches that are, fortunately for tourists on foot, clustered in and around Vicenza.

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The Basilica Palladiana (1549) is his one great civic work, a wrapper around a medieval basilica that, like Alberti’s wrapper around a gothic church in Rimini was an exercise in restyling and in finding a stylistically presentable facade for an existing, less-fashionable structure.  Palladio’s threefold bank of architectural knowledge is on full display here–he handled the technical challenge involved in attaching a rigorously ordered facade to a decidedly irregular chassis, every element of the facade is archaeologically correct (never mind the supposed influence of Michelangelo’s more histrionic inventions), and the composition is absolutely perfect–including adjustments to the corner bays that solve the dogged corner problem almost effortlessly.  By this point he was fluent in stonework, fluent in the proportions and details of classical precedent, and finding his way toward the mathematics that linked, to him and his contemporaries, architecture, music, and a divine celestial harmony.

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What’s most interesting to me in his work, and in writers like Wittkower’s analysis of it, is that there is a different attitude toward this connection to the divine, and to an overarching universal order.  In Gothic building, you often here about the attempt to literally build the theology of Augustine–to replicate as nearly as possible the City of God in the cities of men.  This led to all sorts of numerological devices, and a rigorous order applied to cathedral planning that was based on three ratios–the square, the half-square, and rectangles with a ration of 1:1.414, or the square root of two.  Brunelleschi and early Renaissance architects continued these ordering principles, believing that whatever was numerically ordered would be beautiful and strong–Francesco di Giorgio wrote of this process as guaranteeing fortezza e bellezza.  But Palladio’s treatise has a different tone.  His family of proportions is much more complicated, using ratios that appear throughout the harmonic scale.  Which ratio to use?  While there are rules, there are often two sets of rules–geometric and harmonic (Wittkower explains these thoroughly…), and there’s an implied choice for those designing rooms.  One works best for small rooms, the other for large rooms, and it’s up to the designer to figure out which.   Palladio also appeals to architects to make their own judgments about whether a wall is thick enough to carry its load.  No longer were architects bound by rules that had simply been handed down by authority–either of the ancients, or the divine, or by custom.  Instead, there’s a porto-scientific sensibility to Palladio’s writing.  Try this, and that, and maybe this, he seems to advise.  Use your judgment to determine which one has the best outcome.

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That’s a libelous simplification, but it resonates with with the confidence and the thoroughness of his work.  Villa Rotonda is really a statement about the capacity for humans to actually instantiate a bit of the divine on earth–and not just in liturgical spaces.  This was a giant party house, and yet Palladio felt it was thoroughly deserving of all the interlocked proportions, the mathematical rigor, and the pitch-perfect execution of a temple–thus the dome and the pediments, among other things.

It’s the Palazzi, though, that are the most interesting to me, because they inevitably deal with imperfect sites, were rarely finished, and yet show how this combination of disciplined conception and composition, combined with an understanding of how buildings actually worked and were put together, could create stage sets of cosmic perfection and visual serenity out of the most chaotic urban situation.  Most of his work in Vicenza is on narrow streets, meaning you never get the big elevation view–instead, he used what little depth he had in the facades to create striking rhythms of shadows and highlights.  But the elevations are often perfect anyway (or, in some cases, imperfectly perfect, like where the existing courtyard wouldn’t allow a symmetrical entrance–here, he seemed unperturbed about violating the one cardinal rule of classical composition, and such violations seem to disappear in such narrow fields of view).

valmarama

Here, on Palazzo Valmarana (1580), you can see that even he wasn’t against a few Mannerist games–look at the end pilasters and you can see that he’s replaced them with statuary.  But even here those games happen within such a fully detailed composition that they don’t seem jarring.  In fact, if you stare at this long enough (and there’s very helpfully a nice cafe across the street that will happily serve you a Campari and soda while you do this–note to architectural tourists) you start to realize that what he’s done here is to create two facades–one that’s the full breadth of the elevation, and one that is just the five bays framed by the giant order.  The two of them are compressed on to one another graphically, a trick he’d use in his to church facades in Venice–here’s San Giorgio Maggiore, note the way the two pediments here work like the two interlocked rectangles at Valmarana:

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Anyway, this is all pretty foundational stuff, and to me the most interesting aspect of Palladio is that he bridges this gap between architecture as an aesthetic pursuit and as a purely technical one.  His approach is quasi-scientific, and certainly his compositions start to hint at an order based not in mysticism, but in mathematics.  He was exactly one generation younger than Copernicus, and one generation older than Galileo, and in the geometry and the rich mathematics that underlay his designs I think you can get a sense for the growing realization that a ‘cosmic order,’ far from being ethereal, was about to get very, very evident.

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cesena, ravenna

April 30, 2017 § Leave a comment

cesena interior b+wSlowly winding down a five-week fellowship at the Università di Bologna and catching up on some long overdue tourism.  I spent one day at Cesena, where the University’s Architecture department has a base, and lectured to a nicely enthusiastic crowd of students on our current CHiRG research, which has to do with the technical development of the ‘glass box’ in the 1950s.  In return, I got a fine day out in a small town that deserves more tourist action than it gets.  Cesena, like a lot of small cities in Romagna, was occupied variously by the French, the Lombards, the Papal States, and its own city-state government, and it’s a palimpsest of influences.  Including the oldest public library in Italy, maybe in the world–the Malatestiana Library, finished in 1452 and pretty clearly an influence on Michelangelo’s Laurentian Library, which was started just 70 years later.    Ernesto Antonini, Professor of Architecture there, organized the lecture and generously indulged me with an afternoon at the library and around town.  The piadine in Cesena is, according to the locals, better than anywhere else in Italy, and I’ve seen no evidence to the contrary.  (Think love-child of a quesadilla and a pizza.  Nothing not to like, really).

But then there is also some pure tourism to do, including Ravenna, which I’ve never managed to get to on previous trips.  It’s slightly out of the way, which is why the last gasps of the Roman Empire found it to be a convenient hideout in the 6th century.  The mosaics, as advertised, are spectacular, but it was also fascinating to see well-preserved examples of early Christian architecture of two types–baptistery and basilica–in such close proximity.  Compared with the more vast construction achievements of the empire at its height, and with the more orderly and refined buildings of the Renaissance, this era has always seemed less interesting to me, but then I’ve never seen much of it first hand.  A day of immersion in San Vitale, Sant’Apollinare Nuova, and the Neoniano Baptistery were healthy doses of reconsideration for me, because you can see not only the struggle to match the scale of their predecessors (but without the benefit of concrete by this point, since supplies of pozzolan from Vesuvius were no longer politically possible, and knowledge of the technique seems to have withered entirely), but also to rival what was by then the far superior building culture of the Byzantines to the east.  San Vitale was started a decade before the Aya Sophia, and the similarities in form and structure are clear.  They’re poignant masterpieces–very little of consequence was built on the peninsula for another four centuries after these structures, and they really represent the tail end of Rome’s building culture.

And the mosaics, frankly, aren’t hard to look at, either.

ravenna battistero neoniano 2ravenna san vitale int 1

building machines

April 28, 2017 § 4 Comments

IMG_5898Singing for my supper…and being invited to more speaking gigs in impossibly intimidating rooms.  The University here held a symposium here this week on the role of the Manifattura Tabbachi in Italian culture and Bologna’s history, with contributions from literary and labor history scholars about the larger scope of the Italian state’s monopoly on tobacco (and salt, etc.) in the 20th century.  Who’d turn down a chance to sit in when the venue is a 16th century hall with frescoes by Fontana and a staircase by (maybe) Bramante?

Whether I did justice to it or not is another story.  My fellowship here has revolved around Nervi’s warehouse and production facility for the monopoly in Bologna, and after a semi-official tour organized by Jacopo Ibello’s Save Industrial Heritage organization and some enlightening conversation with scholars and students here I’ve been looking at the processes Nervi used to build the ballete, which is relatively famous as an example of his interest in patterned slabs using ferrocemento formwork.  The Gatti Wool Factory is the most famous of these (and the subject of a particularly good fence-jumping adventure five years ago), but Bologna was his first built experiment in the expressive potential of ferrocemento formwork, and thus of particular interest.

tabbachi expansion joint

It’s a subtle detail, but you can see from the image above that, unlike conventional two-way, or “waffle” slabs, Nervi’s slab design here includes subtle flare-outs of the joists as they approach the girders, an acknowledgement that shear forces within the former are increasing as they pick up more and more load from the slab above.  You can also see that the girders flare out (in section rather than in pain) as they approach the columns, reflecting the same principle.  These aren’t really necessary statically, but they resonate with our understanding of the way the stresses in the frame get collected and transferred –whether you know your two-way slab theory or not, I’d argue that this looks intuitively satisfying in ways that a conventional waffle slab doesn’t.  It’s a nice, thoughtful piece of ornamentation in the Albertian sense–of clarifying how things are actually working and visually emphasizing the story Nervi wanted to tell.

Ferrocemento allowed him to do this, since the formwork pans were produced by bending wire mesh over a clay mold and then troweling the result with lightweight cement wasn’t limited to the straight, flat surfaces of steel or timber forms.  Nervi had used the material with great success in naval experiments during WWII for the Italian Navy, and for the sublime–but incredibly efficient–roof of the Salone B at the Turin Esposizione.

tabbachi pan closeup

So, between my archival trawl a few years ago and the brilliant work of Sofia Nannini, whose thesis here at Bologna this year was on the Tabbachi, there’s enough information to reconstruct Nervi’s process, and–maybe more interestingly–to reconstruct the ‘machine’ he used to form these slabs.  Photos of the construction site show this–brigades of light scaffolding with pans on top, set onto rails that allowed crews to raise them into place, pour concrete over them, and then once the concrete had cured to ‘disarm’ the formwork by lowering it on the scaffold and move the whole system up seven bays, or one week’s curing time.  (English doesn’t have a word for removing formwork, but in Italian it’s disarmare.  Like cantiere, a word that means both “shipyard” and “job site,” this is one of those linguistic oddities that tells you just a bit about different attitudes toward construction between the two cultures…)

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I’ve spent a few days building some very basic digital models that future CHiRG research assistants will (I hope) clean up for me, but enough to get the basic sense for how the machines worked and what they defined about the building form.  Nervi noted in his notes, and elsewhere in correspondence about the Reynolds project that how you think of scaffolding determines a lot about the building.  In this case, the linear process inevitably led to an extruded, but punctuated, form.  But it also imprinted the Tabbachi with a distinctly human scale.  While other engineer-builders like Candela struggled to make their evocative forms relatable in terms of their scale, Nervi’s process always relied on elements–in this case the individual pans–that could be lifted by no more than three or four laborers, a way of keeping his crews small and his costs down.  Today we can read that measure into almost everything he built, which offers an instantly legible grain to his otherwise vast constructions.  If the machine itself reminds me of Brunelleschi, who was trained as a clockmaker and whose cranes and engines for Florence’s Duomo were as impressive to many as the finished structure, Nervi’s end results remind me of Alberti, who pointed out that beauty never arose strictly out of a building’s order, but instead out of how that building’s order was rendered in actual matter, and how that rendering was explained visually through proper ornamentation.  It might just be the surroundings this month, but these sorts of parallels seem stronger and stronger the more I delve into this…

Thanks to Micaela Antonucci, Elisabetta Margiotta Nervi, Jacopo Ibello, Sofia Nannini, and a host of local caffè purveyors for their help in getting this rolling…

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turning a corner

April 17, 2017 § 1 Comment

During last fall’s research trip to Chicago, SOM’s Bill Baker and I got into a conversation about the intractable problem, in architectural detailing, of turning a corner.  You’d think this was an easy thing, but any wall with a thickness makes a 90° turn (or, really, any turn) something of an issue, especially in so-called ‘re-entrant,’ or inside corners.  Especially if you’re anything of a structural rationalist and want to emphasize the importance of your structural grid, because as the layers of the wall sprout out from the column line, the edge line of your elevation and the grid line of your plan start to diverge, with consequences that you can’t fully understand in two-dimensional drawing.

That’s something of a moot point these days, with the ease of digitally modeling in 3-d, but historically it’s been a point of some debate.  If the edge line of the building (the “demise line,” in the more theatrical British term) doesn’t coincide with the structural line, then what do you emphasize?  Do you make the corner lightweight, trying to make it disappear?  This was an established International Style approach–pioneered by Walter Gropius but absolutely employed by SOM in their classic glass skyscrapers.  Inland Steel took a particularly brave stance, making external corners of its floor plates and re-entrant corners of its cladding system.

By the end of the evening, we’d pointed out to ourselves that this wasn’t just a skyscraper problem, and that the corner had produced headaches and inspiration for a few hundred years.  And in the last couple of weeks that conversation has fueled a few detours to find examples of Renaissance architects struggling with this problem–how to express a one-dimensional grid line that gets manifested in three dimensional material.  Or, in Alberti’s words, how the lineaments of a design, which exist only as mathematical entities, get expressed in the matter of design, the actual stuff that buildings get made of.

Here’s the crux of the problem: Brunelleschi’s cloister at Santa Croce (1453):

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You can see what he’s done–the column lines supporting the two arcades both hit on one single point, where the corner column is located.  This is correct in plan, correct in elevation…and totally wrong in perspective, because our eyeballs correctly read that the thrusts of those two arches (which, admittedly, aren’t that much physically because of the nature of the wall, but are still visually how we read the arcades) as trying to topple the column back into the cloister behind it.  It’s a visually weak detail–the column doesn’t have the whoomph (technical term) to resist the visual pressure being put on it.  (Also, the arches collide with one another in a detail that’s visually awkward and undoubtedly cost a few extra florins, as the stonecutters had to figure out the tough three-dimensional geometry of intersecting arcs).

But it wasn’t just arcades that gave Brunelleschi fits.  In the Old Sacristy of San Lorenzo, you can see that he knows there’s a ‘column’ at the internal corner of the main space, but the wall folds it in two, leaving it kind of stuck.  Its counterpart in the background is also clearly not happy:

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Alberti faced the arcade problem in the Rucellai Palace (also 1451)–not open to the public, but you can see this in the Strozzi Palace, designed in the 1480s and clearly patterned on Alberti’s work:

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It’s odd that Alberti would have struggled with this, since his re-invention of the pier and engaged pilaster actually provided a reasonable solution to the problem.  By giving the arches and the architrave above separate vertical elements, his successors discovered that you could have the arches land on their supports, turn the corner on the ‘column’ that now found itself buried in the depths of the pier, and then start fresh around the corner.  Here’s Bramante figuring this out in the cloister of Santa Maria della Pace in Rome:

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There’s still the problem of the trapped column, though, right?  It turns out that if you adhere so strictly to the fairly simple rules that Vitruvius and Alberti codified, there’s no good way to turn this corner–either you end up with a weak corner or you trap a column inside a pier.

The trick turned out to be offsetting the grid by a column’s width and tripling up on columns in the corner, creating a dense area of detail while making the corner structurally and geometrically sound.  Michelangelo figured this out in his redesign of the Farnese Palace’s courtyard:

You can see that the first column in each wall is actually offset from the actual grid, like this (or, you can think of it as Michelangelo shortening the inner bays of the grid to ‘dig out’ the otherwise trapped column):

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This trick shows up all over the place for the next five hundred years–in Schinckel, in Mies, in almost anything designed by an architect obsessed both with order and with the visual effects of expressing that order.  What I like best about this story is that the apparently ‘perfect’ rules of antiquity contained within them inherent contradictions between what the building order ‘wanted’ to be, and what our eyeballs want to see.  And it took some futzing around on the part of Bramante and Michelangelo to figure out how to get our senses and our minds to both be happy with what they’re seeing, even if it required a bit of fiction and chopping out a thin layer of building to get back to the grid we’re expecting.  It’s a classic case of “the lie that tells the truth,” to paraphrase a colleague of mine.  Or, as Vignola put it, right around the time Michelangelo was working on the Farnese,

“Should someone judge this a vain effort by saying that one cannot lay down a fixed rule, since, according to the opinion of all and especially of Vitruvius, it is often necessary to enlarge or to diminish the proportions of ornamental members in order to remedy with art where our vision has been deceived by some occurrence, to him I reply that concerning this matter it is necessary to know how much should appear to the eye…and then proceed in this by certain good rules of perspective, whose practice is fundamental both here and in painting…”