PHILADELPHIA -- "This is brutal!" said Jim Johnston, regional manager for Ben & Jerry's Ice Cream, as he dug a spade into a rock-hard carton of New York Super Fudge Chocolate. "Our relief was supposed to be here two hours ago."

Johnston, who was constantly interrupted by a coworker's shouts ("One Mint Oreo! Two Cherry Garcia!"), said he hoped to dish out 300 2 1/2-gallon cases during the 12-hour marathon known as The Great American Picnic, the culinary highlight of Constitution Day celebrations here.

As jazz bands played, balloons filled the air and tall ships bobbed in the water. Hundreds of thousands of slightly soggy -- it rained yesterday -- celebrants came to the Delaware River waterfront to toast the 200th anniversary of the Constitution's signing with more than 10,000 gallons of Coca-Cola.

Like many of the companies here, Ben & Jerry's was donating much of the ice cream and would make no money on the event. "For us, it's the exposure for the product," Johnston said.

The ice cream maker was not the only company advertising its wares at Penn's Landing. Gannett, publisher of USA Today, gave away 20,000 copies of the newspaper and countless blue and white helium balloons.

There were also USA Today Teddy Bears wearing USA Today T-shirts, and, a newspaper-toss contest featuring a prize that was the focus of yesterday's celebrations. "Win a condensed version of the Constitution," USA Today employe John McGee shouted at passers-by during a huge gathering along the Delaware River.

Coca-Cola (both New and Classic) hung banners everywhere. The Goodyear blimp hovered overhead. And Philadelphia television stations provided live coverage of the picnic as the city, which was America's largest and richest in 1787, patted itself on the back for throwing a great party.

Along the river, as four jazz bands took turns playing, hundreds boarded the Moshulu, an 84-year-old German warship confiscated by the Allies after World War I. The ship, now docked here as a restaurant, was doing a brisk lunch business (baked stuffed shrimp, $16.95) and selling $3 tickets for last night's fireworks display.

The politicians and VIPs, meanwhile, walked down the pier to the luxury liner Royal Viking Sky, where they dined on corn chowder, sea bass, roast turkey, Pennsylvania red cabbage and sherbet.

Most of those running the concessions, which included 250,000 hotdogs, taco salads, pierogi, snow cones, popcorn, candy apples and funnel cakes, said they were veterans of big outdoor events such as July 4th.

"We drove up from Palmerton, Pa.," said Bonnie Wargo of Smitty's Famous French Fries and Pierogies as the steam from potatoes frying in oil wafted up behind her. Wargo said she got the concession because she works for the man from Kiss Fresh Fruit, who was selling smoothies (blended fruit drinks) across the plaza.

No bicentennial celebration would be complete without the long arm of the federal government, which was here in the form of a U.S. Census Bureau booth. An electronic scoreboard told onlookers that America's population, as of 1:30 p.m., had hit 243,928,744. By adjusting for births and deaths, the machine adds a new American every 16 seconds.