REVOLVING DOOR.(restaurants)

New York, unlike the great capitals of Europe, has always been a city of reinvention. Manhattan schist excavated during the construction of the subway finds new life as an apartment building on Riverside Drive; meat lockers on Gansevoort Street become expensive shoe salons; an Art Deco bar, abandoned in Murray Hill, is transformed in 1980 when it's relocated, like a Lego block, to a new restaurant in Tribeca called the Odeon.

Evan Blum, who runs the architectural-salvage shop Demolition Depot (and who facilitated the Odeon transfer for Keith McNally), is the city's recycler-in-chief. He is the major dealer in "vintage doors." On the third floor of his warehouse, on 125th Street, below bathtubs and above stained glass, he keeps thousands of them on display: "single French doors," "double French doors," "doors with glass," "rear doors," "entrance doors," "sets of doors." At his shop recently, he said, "They don't look special, but more people have a need for ordinary doors than you could imagine. This is a very important service to New York."

A few of Blum's favorite doors line the shop's stairwell. On the ground floor are two pairs of elegantly inlaid wooden doors from the Palmer mansion, in Chicago ($50,000 for the set), and an Upper East Side town-house door whose iron trimmings were painted bronze in the Second World War to avoid detection during scrap-metal drives ($8,500). Another door, made of wood, with a window of thick frosted glass, leans against a nearby bannister. On it is printed "Office of the Chancellor, Joel I. Klein," in black-and-gold-leaf lettering. Blum calls Joel Klein's door "an artifact of current interest," and, therefore, it is available only for rental. ("I thought people might find it useful for photo shoots," Blum said.) Blum is reasonably sure that he rented it once, briefly and at a "nominal price," but he can't recall when or to whom.

Klein's door comes from the tenth floor (Room 1010, it says) of 110 Livingston Street, in Brooklyn, the former headquarters of the Department of Education, where Klein worked for only two weeks, in 2002, before the department moved to the Tweed Courthouse. Blum picked over the interior of 110 Livingston Street, which was designed by McKim, Mead & ...