Manhattan wine merchant William Sokolin can make this boast: He spills no wine before its time.

Last month, while attending the annual $250-per-person black-tie Bordeaux dinner at the Four Seasons restaurant in New York City, he broke a bottle of 1787 Château Margaux—a celebrated Bordeaux wine that he had valued at more than a half-million dollars. But all was not lost. Opportunely, 193 guests were on hand to witness history dribble onto the blue-and-gray carpet of the Pool Room, and enough of them were wine writers to ensure that this would be the most publicized breakage in the spirits world since Eliot Ness took a sledgehammer to Al Ca-pone’s warehouse.

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The bottle, inscribed with the initials Th.J. and discovered behind a Paris cellar wall in 1985, is thought to have been the property of Thomas Jefferson, who wrote the Declaration of Independence and found Bordeaux a happiness worthy of pursuit. Another bottle in the cache, a 1787 Château Lafite, was bought at auction in 1985 by publisher Malcolm Forbes for $155,453, making it the most expensive wine ever sold. Sokolin received the 1787 Margaux on consignment from a British wine firm, and he recently declared it to be worth $519,750, a price he set impulsively after attending an auction and seeing “a footstool that looked like it would fall apart” sell for $290,000.

In the wine trade, Sokolin has a reputation as an unabashed self-promoter who sometimes acts as though his own cork is a bit loose. He has sold a Mexican liqueur for its aphrodisiac powers, advertised a $5 Bordeaux as the equal of Château Mouton-Rothschild and written of his mystical attachment to Jefferson. “I talk to Jefferson,” he says frankly. “But he doesn’t talk to me.” Sokolin has so often sought public attention for himself and his wines that a question of credibility arises when he says the bottle (insured for at least $200,000) broke by accident (in front of the perfect crowd). “You think I did it on purpose, don’t you?” he asks.

In fact, his actions indicate that he didn’t. Only after sitting down at the Four Seasons dinner, Sokolin says, did he remember that the guests of honor were the owners of Château Margaux. Then, he says, “something hit me—why should this bottle be in a dark, dark cellar when it could be at a party for it with Jefferson looking on? I was pulled out of the room like I was magnetized.” He took a taxi to his apartment, retrieved the bottle from a refrigerated vault, rushed back and began showing it around. Sokolin, who played in the Brooklyn Dodgers farm system before inheriting his Madison Avenue wine shop from his father, particularly wanted to show the bottle to Rusty Staub, a former major leaguer turned restaurateur. Although Sokolin claims he had “great hands” as a player, he clumsily bumped the bottle against either the arm of a chair or the sharp edge of a serving table as he headed for Staub. “When it happened,” he says, “I was numb.”

The bottle did not shatter. Perhaps because the old glass was not of uniform thickness, it sustained two large holes but remained intact. As the wine sloshed out, Sokolin rushed from the room, embarrassed, he says, at what he had done. He remembered to take his wine with him but forgot to take his wife, Gloria, a real estate broker. “Somebody had to lend me $5 to get a taxi home,” she says. When Sokolin reached the coatroom, he momentarily put the bottle on a counter, leaving a puddle that restaurant manager Julian Niccolini dipped his finger into for a lick. His tasting note: “Yuck.”

When he got home, Sokolin thought of posterity and froze what remained of the wine in a plastic food-storage container. The bottle went on a living-room table, next to a copy of Liquid Assets, Sokolin’s book on investing in wine. As he paced the room a few days later, speaking sadly of all the TV and newspaper references to him as a “clumsy oaf” and a “boob,” he bumped the table, knocking the book into the bottle, which started to tip but stayed upright as Sokolin dramatically clutched his heart.