The Brooklyn Bridge had several attributes that made it particularly well suited for this sort of endeavor. Its proximity to the port made it highly visible to newcomers who might be likely marks, and its size provided opportunities to show it off while avoiding the law. But perhaps most critical was its considerable fame. "In the 19th century," said Kathleen Hulser, the public historian at the New-York Historical Society, "the bridge was one of the two best-known symbols of America," the other being the Statue of Liberty.

Vendors of the bridge not only counted on the gullibility or greed of their targets; they also appealed to their vanity. Buyers could believe, as Mr. Sifakis put it, that "they had become real men of substance, great capitalists."

"All great monuments will have swindles built around them," he added. "The appeal is to own a piece of the rock."

Even as the nature of the immigrant population shifted, the scam endured. "Up to the 1920's people were still trying," Mr. Nash said. "But it was a hard sale. Immigrants had become much more sophisticated and knowledgeable, and by that time the processors at Ellis Island were handing out cards or booklets saying, 'You can't buy public buildings or streets.' " These shifts explain why the Brooklyn Bridge is the span associated with swindles; the city's other bridges were built after the high tide of gullibility had already begun slipping away.

Long after actual sales of the Brooklyn Bridge subsided, the concept still roused the public imagination and remained embedded in popular culture. In the 1947 movie "It Happened in Brooklyn," Frank Sinatra played a young private home from the war who sang plaintively to the woman he loves: "Don't let no one tell you/ I've been tryin' to sell you the Brooklyn Bridge." Even Bugs Bunny got in on the act; in the 1949 cartoon "Bowery Bugs," an old man is so charmed by the rabbit's tale of the famous bridge jumper Steve Brodie (Brodie's feat, alas, was a hoax) that he agrees to buy the bridge from him.

AND because of the Internet, which has provided seemingly endless new opportunities to propagate frauds, there's life in the old con yet. One particularly memorable attempt to sell the bridge is documented on Scamorama.com, a Web site that presents e-mail exchanges between would-be scammers and their not-so-gullible targets.

In one, a swindler using the name Genevieve e-mailed a target calling himself Vidocq (a pseudonym that should have warned off the scammer, it being the name of a famous French criminologist). In broken English, the scammer presented a convoluted story of riches tied up after a coup in Liberia and tried to entice Vidocq into sending money to help gain release of the funds. Vidocq did his best to gain the swindler's trust, then turned the tables by offering shares in the Brooklyn Bridge. The notion piqued the swindler's interest, and an involved exchange of e-mail messages followed before the scammer finally realized just who was being conned.