Far earlier than just about anyone else, Karp recognized that many of New York’s late-Victorian stone and terra-cotta facade ornaments—keystones, plaques, and friezes, even those that embellished tenements and rowhouses—were artworks in their own right. Spurred to action by their wholesale destruction at a time of galloping development, Karp spent several years scooping up the forsaken fragments by himself, before joining forces with a few friends whom he led on clandestine raids of demolition sites. In homage to the immigrant artisans who had created the unsigned ornaments, Karp named the group the Anonymous Arts Recovery Society.

“I was a rubble rouser,” Karp says.

Armed with crowbars and the occasional hand winch, the group rescued some 1,500 artifacts from around the city. When the scavengers’ backyards became overcrowded with the mythological creatures and deities and grotesques they had saved, Karp approached the director of the Brooklyn Museum, Thomas Buechner, who agreed to let the group store the sculptures behind the museum. Karp and his friends soon dropped off some 400 fragments. About a quarter of the objects were destroyed by the elements in those early years.

Then, in 1966, the museum built the Frieda Schiff Warburg Memorial Sculpture Garden to display roughly 200 pieces of stone carving, terra cotta, and ironwork. It grew, supplemented over the decades by Karp and other donors, and became the public centerpiece of the only major repository of the late-Victorian and Beaux Arts architectural ornaments that had once enlivened the city in such startling numbers and variety. The treasures included a roaring zinc lion from the El Dorado carousel in Coney Island and a languorous allegorical figure of Night, carved of granite, from the iconic Pennsylvania Station complex designed by McKim, Mead & White. I asked Buechner recently why he had thought the ornaments were worthy of a permanent exhibition. “It’s like asking me why I think Rembrandt is a good painter,” he replied.

Today, huddled together in a kind of fenced refugee camp behind the Brooklyn Museum parking lot, most of them on rotting wooden pallets, rest scores of Gotham’s most exotic and least appreciated residents. Griffins and sea monsters, gods and kings, most of the inmates of this forlorn encampment spend their days and nights with their weathered faces turned to the heavens. When it rains, water pools in the vulnerable sandstone eye sockets of some and nourishes the green biological growth that clings to others. In winter, water freezes in the bowl-like terra-cotta medallions, imprisoning in yokes of ice the heads of women and animals that protrude from them. It’s a pretty shabby habitat for creatures once displayed so proudly. Ten years ago, the Brooklyn Museum dismantled the sculpture garden during a reconstruction of its rear entrance. And although a reinstallation in 2004 resulted in a far sparser garden of 62 fine artifacts, 275 relics of New York’s lost streetscape still languish in limbo behind the parking lot of the financially struggling institution. But as they enter the second decade of what Karp bemoans as “perilous and baleful banishment,” many may finally be on the move. Over the past few years, the museum has quietly begun deaccessioning—the genteel art-world euphemism for “getting rid of”—large numbers of its city artifacts. In 2006, it transferred some 1,500 terra-cotta pieces, originally from a 19th-century Romanesque-style Brooklyn church, to a foundation in St. Louis. In 2008, the same group took possession of about 200 limestone fragments from the 1910 Gothic Revival facade of a West 57th Street townhouse. And in January, four circa-1920 cast-iron lawn jockeys, manufactured for the 21 Club, were auctioned off at Sotheby’s Important Americana sale. Such transfers are just the beginning of the museum’s broader effort to dramatically shrink its collection of city architectural ornament. Without notifying Karp, curators have been planning to sell more than a third of the remaining collection through a Harlem salvage dealer.