When the three "art handlers" mounted the painting "Rubens Peale With a Geranium" in Lobby D of the National Gallery of Art yesterday -- two holding it and one screwing in the supports -- it was business as usual for handler Gary Webber.

"It's a routine installation," said Webber, who can mount a Degas on the wall before you can say "Picasso" or vice versa. "There's nothing unusual about this hanging except there's cameras and all kinds of strangers watching."

And lights. And National Gallery Director J. Carter Brown calling it a "superstar" American painting. And the fact that this 28-by-24-inch picture cost the gallery $4.07 million at a Sotheby's auction last week -- the most expensive purchase of an American painting to date. Today marks the painting's first public viewing.

"The auctioneer puts you through the tortures of the damned until the hammer falls," said Brown, who was present at the auction. The $4.07 million figure, he said, was a relative bargain: "It could have gone very much higher," said the director after yesterday's picture-hanging ceremony. "There were rumors that the thing would go $5- to $6 million."

Brown, who had asked for donations after last week's purchase -- his tongue-in-nonprofit-cheek -- said he has not received any offers, but "the mails take a while at Christmastime."

One reason the gallery saved a million or two, said gallery Deputy Director John Wilmerding, was that Ambassador at Large Daniel Terra, owner of the Terra Museum in Illinois, and Ruth Stevenson, who owns the Amon Carter Museum in Fort Worth, didn't take part in the bidding. Terra and Stevenson are also trustees of the National Gallery and "both generously stepped aside . . . Had they not been on the board, they certainly would have bid for it," Wilmerding said.

Why this American painting? The 1801 painting, Rembrandt Peale's portrait of his brother Rubens, the subject's hand on a potted geranium, is certainly masterful. But $4 million masterful?

"This picture has been on our want list ever since I've been associated with the institution," said Wilmerding. "It's the first time a painting in this category has come up for public auction."

"This picture goes so closely with that whole Jeffersonian idea of a new republic, an interest in science," said Brown. "That tell-it-like-it-is American forthrightness . . .

"It's such a wonderfully human document," he continued. "I think it has tremendous appeal; it's a very lovable picture. Part of it is you feel Peale was relaxed, he was painting his own brother, he wasn't doing a stiff official portrait for which he was being paid hard cash, which would trigger all his self-consciousness."

In fact, said Brown, referring to Peale's portraitures, "Rembrandt Peale doesn't turn out to be a very interesting painter. But when you catch him like this, recording someone he obviously cared about . . . There is a lot of love in that picture and I think that's part of what gets communicated."