Every New Year's Day - or at least every New Year's Day for the last four years - the National Academy of Sciences holds an open house. So yesterday found a group of exceptionally un-hungover-looking scientists, doctors, politicians and friends trickling in and out of the National Academy of Sciences building.

In a main foyer softened by candlelight, guests wandered sedately about or clustered around a sumptuous buffet table while being serenaded by three violins and an accordian on an upper balcony.

"You know," said Dr. Phillip Handler, president of the academy, "this is the first year we haven't used brass," referring to the music. "Generally I think brass is more in the character of this hall, which I find rather gothic, don't you?"

The crowd, with the exception of such notables as former Sen. William Fulbright, Rep. John Brademus (D-Ind.), Roger Stevens of the Kennedy Center, and Donald Kennedy, head of the Food and Drug Administration, was largely scientific. Perhaps that is why there seemed to be fewer cigarette smokers than usual, and no artificial sweeteners for coffee drinkers.

"Of course there's no saccharine here. My agents are everywhere," noted Kennedy.

On the other hand, Ruth Hanft, deputy asisstant secretary for health policy, wasted not a moment before lighting up her own cigarette. "Yes, yes. People are always telling that in my position I shouldn't be smoking. But to each his own."

Daniel Schorr noted that his role there was "being a spouse," since his wife, Lisbeth, is a member of the council of the Institute of Medicine of the National Academy. However, Schorr did say that in three months he will be starting a weekly syndicated newspaper column.

"It's going to be a Washington column," said Schorr, "where for the first time all the beats I've covered in my life will come together in what I write."

Meanwhile, while piling a plate with ham and cheeses, one Scott Forbush, a retired member of the Carnegie Institution of Washington, noted that "I just don't see as many of my old friends here this year as usual. You know when you've retired from the sciences, this party is always the place you know you will see many of your old friends. Personally, I spent my career in the field of terrestrial magnetism - doesn't that sound awful? However, now that I'm retired, I simply spend my time playing the cello and relaxing bylearning something about molecular biology."