Cigar in one hand, vodka and consomme' drink made from a special mix in the other, Milton Berle was being Milton Berle.

"You're too tight," he informed the crew of photographers snapping away at Sid Caesar, Steve Allen, Jayne Meadows, Andy Williams and Lorne Greene at a reception last night in honor of NBC's donation of 20,000 programs from 1948 to 1977 to the Library of Congress. "I bet I'm not in it. You want a wide shot?" And on he went, directing and advising and kibitzing.

"I never drank before last week. Then someone gave me a taste of this," he said, lifting the drink.

Corrupted at age 77?

Berle responded with a leer broad enough to reach the last house in the littlest town with the weakest TV signal.

As the photographs continued in the Dirksen Building reception, Berle never stopped.

"I knew it was a sham!" he fired at NBC Chairman Grant Tinker, grabbing a photogenic film canister "symbolically" representing the NBC donation. A Berlean wink and then another followed.

"There's nothing in it!" Berle prepared to hurl the canister across the room.

And the show, part nostalgia, part lunacy, went on.

"I'm excited," Steve Allen said of the evening, which included a dinner for 200, including leaders of the House and Senate, in the Capitol's Statuary Hall. "Of course, I'm easily excited."

A cable network recently ran a skit of Allen and Meadows', he said. "The Annual Prickly Heat Telethon. I heard from a lot of young people who said it was better than most of what they're seeing these days."

But if the new isn't so good, just tune in on the old. Sid Caesar recently finished taping introductions to 65 episodes of "Your Show of Shows" that will be released for syndication this fall. "I introduce it personally because it's very personal to me. It's your life, it's your whole life, and it's something very, very dear to me. It was the golden age in the fact it was live -- no tape, no cue cards. You had to really do it. If you didn't get a laugh you went on very quickly. You were always aware something could go wrong -- that added another dimension. Now it all comes in a nice little package with the laughs.

"I lecture to kids a lot. They want to know! They really don't know what live is. Ninety-five percent of the audiences don't see any live entertainment. They don't have a sense of the immediacy. With live TV, you have to be prepared. You have to be prepared for life, and live TV teaches you to be prepared for life."

Lorne Greene, whose face was as tan and sleek as well-oiled wood, was wearing the evening's sole tuxedo. The victim of a sartorial communications slip, he said, "I didn't know they'd changed their minds about tuxedos."

His NBC past, like Caesar's, lives on. "When 'Bonanza' started, I thought, 'We may last three months, if we're lucky.' Fourteen years later . . . "

Fourteen years later, in 1973, the show finally left the air, but it has been running ever since in syndication.

"The BBC just bought it for the fourth time, and the head of BBC publicity in London called me up and said, 'Why did they buy it?' I said, 'Have you seen the show?' He said, 'No.' I said, 'I'll tell you a secret. I don't know if I can explain it to you without using a four-letter word. It's a four-letter word and it's spelled L-O-V-E. That's what 'Bonanza' is about -- love of family, love of animals, love of environment."

If it all seemed something like a trip down Video Lane, that's in the nature of the medium.

"People think when they used to see you on TV and you're not on that you're retired or dead," said Andy Williams, who added that all it means for him is that music variety shows are out of fashion.

"They've been replaced by things like MTV. Time goes on and music changes and television changes. We had our time in the sun, and new people came along and did their thing. It doesn't mean we are old and we're dead and it doesn't mean we aren't doing anything. I still sing a lot, it's just not on television. There isn't any real need for me or Frank Sinatra [on television] but you still work a lot."

The NBC donation is the first network gift of its kind.

"We're not in the business of saving as much as we are in the business of offering entertainment," said Tinker, another well-tanned man.

Over the years, some shows have been lost, although Robert Saudek, chief of the Library's motion picture, broadcasting and recorded sound division, thinks less has vanished than some television doom-sayers claim.

"That which has disappeared surfaces very often," he said. "What it takes is detective work. Steve Allen said some of his 'Tonight' shows have been burned in order to get shelf space. I said I'd like to look into that one because it might just be a rumor. The rumors happen because of the archivists who are in charge -- it relieves them of the responsibility of looking."

"It's mostly later stuff that got lost -- people didn't realize its importance," said Bud Rukeyser, NBC executive vice president for corporate communications. Once programs were taped, they could be taped over, and sometimes were.

"Actually, last week's 'Cosby Show' is missing," said Tinker.

Just kidding.