Inside Henry Hornbostel's College of Fine Arts building at Carnegie Mellon University, within a sprawling ceiling mural showing history's great works of architecture and sculpture, New York's Hell Gate Bridge looms above the central doorway. A collaborative work by architect Hornbostel and engineer Gustav Lindenthal, the steel-arched bridge with masonry piers accompanies such monuments as St. Peter's Basilica and the Parthenon. At the structure's completion, in 1917, Hornbostel believed that architects collaborating with engineers would bring new aesthetic beauty to major civil-engineering works, allowing such projects to rank with great architecture. That was an emergent idea in the United States at the time, as structures like Hell Gate sought to synthesize engineering and architecture into beautiful form.
Fast-forward to a dual exhibition currently at the Heinz Architectural Center. The Art of Structure includes The Art of Structural Design: A Swiss Legacy, and Felix Candela: Engineer Builder, Structural Artist. Both exhibits are curated by noted engineering historian David Billington (Maria E. Moreyra Garlock collaborated on the latter exhibit), who has criticized Hell Gate for lacking grace. Certainly Horbostel's structure looks positively bovine in comparison to the constructions Billington has gathered at the Heinz Center. But despite the strong case Billington makes for these buildings, the story here is not quite so simple.
Billington, a widely lauded and highly prolific historian of civil engineering for more than 50 years, focuses here (as in many of his articles, books and publications) on structures in the 20th century Modern tradition, especially those constructed of thin-shell, reinforced concrete.
Robert Maillart's (1872-1940) iconic Salginatobel Bridge of 1930, in Schiers, Switzerland, springs blithely from one Alp to the next with a ballet dancer's elegance. His intuitive sense of structure and beauty gave his work a seemingly natural grace and, not incidentally, an utter absence of historical reference. The influential Modernist historian Siegfried Giedion and the Museum of Modern Art became champions of Maillart's designs, a cause for Modernist advocacy that Billington continues to this day.
From Maillart springs a Swiss structural tradition that includes engineers Heinz Isler and Christian Menn, whose more recent works retain a similar weightless elegance. Isler's Heimberg Indoor Tennis Center of 1979, in Bern, Switzerland, looks for all the world like a taut expanse of fabric, though it is actually concrete. Likewise, Menn perpetuates Maillart's legacy of austere restraint in the curving deck and taut cable-stays of 1998's Sunniberg Bridge near Klosters, Switzerland. Similarly, we see Othmar Ammann's George Washington Bridge, in model form, as a paragon of the slender elegance made possible by Ammann's purported engineering genius.
Throughout the exhibit, Billington lauds unity of structure, function and aesthetics. But such achievements are not as straightforward as they may seem.
You'd never know it from this exhibit, but the Salginatobel Bridge became a nightmare of drainage problems, maintenance issues and expensive rebuilds. Historian Henry Petroski, meanwhile, recounts that Ammann's suspension bridges were often dangerously flimsy as first constructed. Only an added stiffening truss -- not shown on the model in the exhibition -- made traversing the bridge safe under heavy winds. In any case, historian Gregory Gilmartin argues that suspension bridges owed their popularity in America not to engineering superiority, but to a Roebling Company construction monopoly.
By contrast, the Hell Gate Bridge is massive because of its mandate to carry multiple tracks of heavy freight trains as a major connector for the Pennsylvania Railroad. Neither its function nor the artistic interests of its time called for the aesthetics of attenuation. For observers at the time, an engineer and architect interested in beautiful bridges were novelty enough.
There is no doubting the excellent engineering of the works on display here, just as there is no doubting Billington's eminence and influence as a scholar. But a viewpoint that sees these works as a special kind of perfection -- rather than the result of particular historical circumstances and compromises -- is just as outdated as Hornbostel and Lindenthal's work must have seemed to Maillart's earliest fans.
The Art of Structure continues through Jan. 17. Carnegie Museum of Art, 4400 Forbes Ave., Oakland. 412-622-3288