For a couple of newcomers, they seemed surprisingly at home.

"After all," said Marvin Sadik, director of the National Portrait Gallery which paid nearly $2.8 million to bring them here, "George picked the site. So, in a sense, it's a homecoming."

Which, indeed, it was last night for George and Martha Washington. After 2 1/2 years of negotiations with the Boston Athenaeum and the Boston Museum of Fine Arts, the long-awaited Gilbert Stuart portraits were where Sadik and others in the Washington arts establishment thought they should have been all along. And today, on the 204th birthday of the country he helped found, America's first president and his lady will begin receiving the family.

Last night some 600 turned out for an All-American picnic marking the Washingtons' arrival. Hastily moved inside when rain clouds hovered ominously above the gallery courtyard, the party didn't suffer at all from the shift. There were hot dogs and hamburgers, beer and pretzels and three flavors of ice cream sundaes for anyone inclined to build their own.

There were a few who lifted a beer in tribute to George and Martha. But most were a little more reverential. Liberated from their oval frames (traces of which still remain on the canvases), the Washingtons were making their Washington debut in splendid rectangular ones made especially for them at a cost of $3,600. The effect elicited no end of astonishment when people realized that the portraits were never finished.

"I always thought that puff of white around George was a cloud, you know, that he was up there with the angels," said Pat Turner, who was accompanied by her husband, CIA Director Sansfield Turner.

For Pat Turner and scores of others in the crowd, school rooms were always "George and the clock -- you watched one about as much as the other." An exception was Stansfield Turner who said he did not remember seeing the Washington portrait in his Illinois grammar school classroom.

"He was a student," explained Turners' wife. "I was a wall-watcher."

Everybody was a wall-watcher last night. "Just the way he's always looked," said attorney Leonard Marks of Washington. "He hasn't changed a bit."

"If I had known he wasn't finished, I'd have tried to get a discount," Sadik cracked to Securities and Exchange Commission Chairman Harold M. Williams. Despite a day that had begun at 6:30 a.m. and included numerous gallery events in addition to the unveiling of George and Martha, Sadik was in high spirits.

"Want to finish them,?" he teased one youngster staring at the portraits. "Get some crayons."

Jeanie Phillips of Alexandria and her son Justin, 6, traded stories about George. "I told him about Washngtons' wooden teeth and he told me about the cherry tree," she said.

Sadik, for one, doubted that Washington's teeth had anything to do with the unsmiling expression on his face. "It was painted at a moment in his political career when he was pretty disenchanted by American politics. He was being attacked on all sides and he was in a grim mood."

Sadik said Stuart probably painted the portrait in one morning -- "He worked very fast and I can't imagine that Washington sat any longer" -- and while no one knows for certain, Martha probably sat for her portrait that afternoon.

Some viewers thought the faint impression of the former oval frame lent a kind of halo effect. Some were struck by the natural flesh tones captured by Stuart. Mary Jane Malone of Alexandria mused that Washington had the look of someone with high blood pressure, but her husband, Owen, an aide to Sen. Henry Jackson (D-Wash.), suspected he's just come in from a brisk ride.

One guest who seemed more blase than the others was Sarah Pollard of Arlington. If her father, Alfred, legislative aide to Sen. Robert Morgan (D-N.C.), chairman of the National Portrait Gallery commission, found it interesting that a couple of unfinished pictures could draw so many people to see them. Sarah, at 6 months, merely yawned.

"It's her second art opening," explained her father.