In his seminal and sometimes impenetrable essay "The Work of Art in the Age of Mechanical Reproduction," Walter Benjamin discusses -- among other tricky notions -- the concept of aura. Benjamin defines this quality as the individual, almost mystic halo that an original work of art may possess for a viewer, and that a copy of that work, no matter how faithful, will forever lack (though the more copies you make, the less aura may cling to the original -- the energy escapes without transforming; it simply disappears).What Benjamin doesn't write about, because it bears no relationship to his thesis, is the way a work of art's aura is drained of energy through a very different kind of reproduction -- that of memory -- and how museums can unwittingly enable this bloodletting.We've all had the experience of coming upon a painting in a museum and feeling so seized in its presence we couldn't walk on. Sometimes, perhaps when our fascination is most alive, we have difficulty making out exactly why we're held so fast. Aura is, in this sense, very like a force field, something that keeps us border-checked.Memory, as neurologists and intuitionists have explained, operates by making copies of copies, a game of telephone. We remember not the incident itself, but the last time we remembered it. Errors become introduced. Nothing can stand up in court.If this is an accurate description of our craniums' wiring then why does an original piece of art not strike us with the same power the ninth or the tenth time we encounter it? The obvious answer is that we've changed in the intervening time, not the work. But might there be more to it?I'm not the first nor will I be the last to note that the new consensus on museum design (the “big white box,” proliferating atria, etc.) might be contributing to the destruction of a museum's most important function: the quiet and very personal encounter between a single viewer and a single work of art; but please allow me to be the latest, and with my own direct experience fresh in mind.Not long ago, on a visit to Boston, where I lived for many years before moving to Denver, I popped into the renovated Museum of Fine Arts (MFA) to see what had been wrought by their recent years-long renovation. The renovation was completed in 2010, but I've only had the opportunity to see it for myself just now.Of course I've changed: I was healthy five years ago and now I'm going deaf; I'm also a tourist instead of a native. But the reaction I had to the art -- art I'd formerly loved and studied -- felt violent and entirely unexpected. I was angry at it, every piece of it. In the new Art of the Americas wing -- a 5-story glass enclosing and paving-over of the old exposed courtyard -- I took in all of the stuff I used to smile over and this time I couldn't get past it quickly enough.I stopped before Joseph Blackburn's portrait of Isaac Winslow and family, and whereas in the past I'd have done little more than smile at the stiff academic poses and the unintentionally ridiculous Rocco accents of the snooty group, I now found myself unexpectedly seething with contempt. Who was this haughty character and his equally awful wife? Was the fruit in his youngest daughter's lap -- a symbol of her eventual fecundity -- not disgracefully sexist? Was his pointed right hand not an incredibly awkward gesture, bordering on the amateur? And not the only amateur of Blackburn’s touches …I moved swiftly along, now looking only for the things that had given me pleasure in the past. Years ago, I took a bench across from John Singer Sargent's portrait of Edward Darley Boit's daughters and spent twenty minutes soaking up the eeriness of the piece, the way he'd used darkness in the mysterious egress in back of the girls, and the odd lonesomeness of each character's pose. I'd also been rightly impressed by the pair of blue-and-white Japanese vases that flanked the painting, as they were the same vases depicted inside the frame, over one hundred years in the fathomless backward of time.I felt none of that now. I imagined instead the fatuous laughter of the vases’ heirs congratulating themselves on their clever bequest. I thought of how the odd moment the painting depicted was just another way for Sargent to show-off with his all-too-knowing allusions to Velázquez, and how Boit's fortune -- the fortune that bought the vases and dressed the room and the girls -- was probably got through sinister devices: the exploitation of ill-treated labor, or the selling of ill-gotten goods. I thought about the sad failure of The Commune in that same city a few years prior, or the hideous treatment of Dreyfus in the years to come, product of a root-deep anti-Semitism that had been festering even then. The painting's aura had changed. It repelled me.Of course I knew that this was all ridiculous. The Sargent picture was in reality every bit the masterpiece everyone had said it was, and what's more the girls themselves had donated it with only the best of intentions. But something drastic had happened to my mood in the fifteen minutes between when I cheerfully hopped off the trolley at the museum stop and found myself bitter and weary in the Americas wing. As I exited back the way I had come, giving up on the adventure before I suffered some kind of nervous collapse, I was finally able to rouse up a suspicion of what it might have been. And not surprisingly, it was all to do with money, money and fashion and glass.One of the charms of the old MFA -- indeed, one of the charms of any medium-scale museum -- is the ability of the viewer, when face-to-face with the reality of a work, to feel for the moment as though they're alone with it, as though a kind of communion is possible, to be able to wander down a lonely corridor and suddenly find themselves caught up in a rush. When I first encountered Elihu Vedder's "The Questioner of the Sphinx" for example, I'd been one of the only people in a dim, soberly colored side room off a corridor at the MFA filled with paintings from a similar period but in entirely different styles; Vedder was more interested in what the French and the Italians were doing than the hucksterish American landscape painters or the dour American realists.I remember feeling like a fish with a hook in its jaw except the hook felt good. I remember burning the aura of the thing into the back of my eyes and knowing then that I would always keep it there. It's there still. A ragged pilgrim kneels beside the lips of a half-blurred sphinx (the sphinx still has a nose, so this is “time immemorial” here being depicted). He seems frantically agitated to know -- what? The answer to existence? The secrets of the past? Beside him rests the skull of another pilgrim. Is the story of the skull's old owner the only one to which our traveler will gain unhappy and despairing insight? Is he in some kind of trance?The style is not painterly: like a less-showy Ingres or Gérôme, Vedder has made his figures as classical as he can, by way of drawing attention not to his own hand, but to the scene itself, the mystery.Now the picture is lost in a spot where few will ever think to pause over it, a functional hall between two grand and glaringly lit American galleries, trapped behind protective glass. The first time I walked past it, I didn't see it.The MFA's new Atrium has been christened The Ruth and Carl J. Shapiro Family Courtyard and its hulking indoor presence has exterminated the trees and grass and wildlife that had formerly flourished there. Now there is a big echoing cafe and a help desk and lots of potted plants and a full glass wall overlooking Forsyth Way, a wall that extends 63 feet to the off-white ceiling. As on the ringing and clanging floor of the Mohegan Sun casino as well as some of the nicer botanical gardens, there is also an enormous glass sculpture by Chihuly.This big room, I realized, was why I was in a sour mood, why I saw the cruelty bred of avarice everywhere I set my eye. That, and the recently jacked-up admission price I shelled out when I arrived. That, and the newness and odd anonymity of the design. I looked at that giant glass wall as my adversary then, and I knew exactly why.Ever since Mies van der Rohe designed and built the Seagram building at 52nd and Park, enormous walls of glass have become the way architects signal their total modernity, how they reach to invoke the play of light, the openness of our new world. But it is exactly the openness of our new world that is the problem with the MFA's new design and the fashion for big glass atriums in particular.I thought of the newly redesigned Harvard Fogg Museum I'd visited only the day before. One of the original charms of the Fogg was its smallness and its antiquity. All of the cozy, peripheral galleries had opened onto an indoor courtyard at the center, but it was not an atrium--it still possessed the quality of charm. Whatever their virtues, huge slabs of glass are never charming.Though the Fogg's renovation was subtler than the MFA's, there was still something I didn't care for in what had become of that courtyard. As your eye moved up from the center, just above the balcony over which brave souls might lean to peer down, you suddenly encounter enormous plates of glass rising before you, several stories worth on all four sides. This has the effect -- though unintentional -- of making the whole of the building seem like an object in a vitrine, something you may admire at a distance but ought not to get too comfortable around.It also vastly changes the relationship of gallery goers with one another. If you're looking across an unobstructed balcony, you may glance at another person in passing, but your dominant impulse is to allow them their privacy: this is their day at the gallery and it need not intrude on your own. But glass does a funny thing to us: it frames scenes in the same way this page is framed by your computer screen, or Game of Thrones is framed when you binge-watch it from the couch. I found myself staring across the glassed-in spaces that frame the center of the 3rd floor with no sense of the voyeur's guilty pleasure. Instead I just watched, unashamed, as though I were watching guards walk back and forth across a big TV. The aura of the old Fogg had vanished in the same way it has for the Mona Lisa at the Louvre. Like that too-famous relic, the building we're occupying is now forever at a distance.But that isn't all. The glass of the atriums at the MFA and the Fogg doesn't only corral the mind in a single direction. We ourselves are being watched with a similar boldness from the other side: we are the fish inside the aquarium, and we stare back with equal frankness as though we were actors in a Brechtian tableaux. Atriums can be just as confining as marble, and indeed may be more so: the more your eye is directed up and around, the less it’s focused on the art in front of you, exactly the thing you've presumably come to see.Indoor glass makes that which appears on the other side of it shiny, and so attractive to our gaze. As I crossed through the MFA's Shapiro Courtyard I realized that all the space and the glass at the new addition (more so than in the the new Fogg) had profoundly altered my sense of the art inside. Instead of the intimacy of echoing corridors, I was presented with the spectacle of the architecture, the big space big money can carve out for itself. I was not alone with the art. I couldn't be.Since the 1880s, my sleepy hometown in a forgotten corner of New England has very quietly maintained in its possession one of the best small museums I know. Thanks to mill-owner John Slater's textile money, Slater Memorial Museum is in possession of one of America's largest collections of Greek and Roman casts (all in overwhelming original size) housed in a beautiful Richardson Romanesque edifice, the interior of which was constructed to resemble the galley of an impossibly captious wooden ship.The casts of Laocoön and Nike, Venus and the Dying Gaul (mostly Roman and Late-Hellenic copies of now-vanished Greek originals) entirely disprove -- one by one and as a group -- Benjamin's thesis about the nature of aura. They are copies, yes, but of a kind no longer permitted: direct impressions cast from the originals, now themselves growing yellow and rather storied in the gloom. Growing up among these things -- I played hide and seek there as a child -- changed me forever. They're more a part of me than anything at the MFA or Fogg and because of that they've lost a good deal more of the aura they once held. I've absorbed it and don't see it in them any longer. But for a newcomer, it is decidedly there.(I've never understood coastal people who move to the interior of the country and loudly lament their loss of the sea. I grew up beside the sea just as they did, and because of that I can never miss it: it's everywhere inside my head; when I see it now, it's like looking in a mirror, and the same is true of those wonderful statues at Slater. Wherever I am, there they are.)I mention Slater here because, since it’s an American museum, it has only this decade become connected to the buildings around it by a large glass atrium. The good news for me is that they did a more friendly-looking job of it than the Fogg or MFA. This is probably precisely because they had a minute fraction of the cash on hand.The atrium at Slater has been dropped into the former location of a small alley that used to run between the museum building and the old gymnasium next door. Exteriors to the left and right are now interiors, and so the atrium itself amounts to little more from the outside than a single glass which, given the givens, is probably the only tasteful way the buildings could have been united. Unlike the Fogg and the MFA, Slater really didn’t have a proper event space, a big room separate from the art where fundraisers could be held and large tours could gather. Now it does.To make sure I wasn't merely seeing the place through the rosy lens of nostalgia, I invited a friend, a professor from Brown University, along for the visit. He had never seen such a conglomeration in a city so small and run-down, and he was as awed as I had expected.I, on the other hand, was instantly at ease. My pride at showing off the place was partially hometown boosterism, and how could it not be? As I walked through the old rooms, gently brushing the bigger cobwebs from some of the statues, the important thing for me was not just to clean them off but that I was the one to do it, that I felt enough at home.We can't separate our egos from our valuations of new architecture in old places, and that's probably as it should be. But there's a reason that the converted textile mills of MassMOCA in North Adams are loved by visitors and the glassy, blank-faced MOMA in Manhattan is merely admired. We want to love our museums, to feel for them, and for the aura they possess to brush against our lonesomeness. I know I could do this at the human-scale Museum of Contemporary Art in downtown Denver, the city that’s now my home, with the same certainty that I know I'll never be able to do it at the Institute of Contemporary Art on Boston's Waterfront, even though one was built in 2006 and the other in 2007. One offers space in which to study the art, the other spectacle in which to admire it. One supports and increases the aura of the work inside, while the other opens a great glass emptiness to drain that aura into Boston Harbor. One is auric, the other vampiric.The atrium at Slater is as separate from the old building as it could be and it's reasonably modest. Strolling through it, one does not hear the imagined clink of glasses or the trickle of vacuous laughter. Instead, one walks a few feet toward the old museum's door and steps quickly inside to be alone and not alone, to let whatever auras we encounter color us as much as they can, to see and feel the art._____John Cotter is author of Under the Small Lights, a novel.