The World's Columbian Exposition of 1893, held in Chicago, advocated the City Beautiful movement by its own architectural example. But besides the classicized façades of the White City, the exhibition got down to detail in the Palace of Fine Arts, where cast-plaster fragments of classical and historical buildings were displayed along with cast-plaster statues after the antique. The event inspired American institutions, including the Carnegie Museum of Art in Pittsburgh, to create their own cast-plaster architecture exhibitions, which looked like Renaissance vedute, those imaginary urban visions of buildings gathered like neighbors into the same collapsed view.

But by the 1920s, plaster cast collections fell out of fashion, discredited by new museological assumptions favoring originals rather than copies. Not long after, Modernism inflicted the coup de grâce. The collections at the Metropolitan Museum of Art in New York and at the Art Institute of Chicago, among others, were dispersed, and their very existence passed out of collective awareness. A very few still exist, and the Carnegie Museum, with its 140 plaster architectural casts still standing in their original position in the Beaux-Arts Hall of Architecture, has the largest in the Western hemisphere and one of the three largest in the world.

The Carnegie's plaster-cast collection is now the subject of a show—“On a Grand Scale: The Hall of Architecture at 100”—in the Heinz Architectural Center within the museum. The show, which closes Jan. 27, 2008, is really an exhibition squared, an exhibition about an exhibition. It takes us back into time twice, to the mindset of a hundred years ago when the collection was formed, and to each chapter in a condensed architectural history representing stone architecture in plaster. The curator, Mattie Schloetzer, has included contemporary plaster sculpture by British artist Rachel Whiteread to demonstrate the tradition of plaster casting transformed into a contemporary vision.

Receding façades: In the Carnegie's Hall of Architecture, a model of the Parthenon sits in front of a plaster cast of the Porch of the Caryatids from the Erechtheum, a temple on the Acropolis in Athens, Greece.
Richard Barnes Receding façades: In the Carnegie's Hall of Architecture, a model of the Parthenon sits in front of a plaster cast of the Porch of the Caryatids from the Erechtheum, a temple on the Acropolis in Athens, Greece.

Along with a sister Hall of Sculpture, the Hall of Architecture was a gift of Andrew Carnegie. The philanthropist believed in educating the public, and plaster casts were the museum equivalent of mass-printed books for the community lending libraries he also endowed. He was not interested in first editions, or costly original Greek and Roman sculpture, but in the ideas that copies delivered. He was educating the public rather than appealing to connoisseurs, promoting the Emersonian ideal of self-reliance through self-education. “The few who travel much fail to remember that the masses of people travel but little,” he said. In short, Carnegie was bringing the Grand Tour to Pittsburgh.

Winston Churchill famously said, “We shape our buildings; thereafter they shape us.” So when we enter the cavernous Hall of Architecture within the larger Carnegie Museum, we are twice edified. The hall contains large-scale fragments of such masterworks as the Porch of the Caryatids from the Erechtheum on the Acropolis and a 12th century Romanesque portal from the abbey church of St. Gilles, in Gard, France (now the largest cast in the world). Smaller pieces include Ghiberti's Gates of Paradise, from the Duomo in Florence, and the Renaissance pulpits of Santa Croce in Florence and the cathedral at Siena. All are arrayed in a peristyle hall modeled after one of the seven wonders of the ancient world, the mausoleum at Halicarnassus in what is now Turkey. A column and capital fragment of the mausoleum is displayed within the descendant building, which was designed in 1907 by Pittsburgh architects Frank Alden and Alfred Harlow, updated via a Beaux-Arts interpretation.

Alden and Harlow miss no opportunity to instruct visitors, both in the architecture of the surrounding museum and in the hall itself. The architects planned the visit to the hall as a processional: Visitors ascend a broad flight of stairs, as though rising into a temple. The exhibition offers experience, and the experience is elevating. You rise to the occasion. Extrapolating from the nature of the exhibits, Alden and Harlow classicized even the museum's bronze elevator cabs, down to the crown moldings of acanthus leaves.