When one political bible adopts another, there's only one thing for both of them to do: Throw a grand party and invite every news junkie available. And then feed them food befitting a political convention: hotdogs, popcorn and lots of scotch.

The National Journal did just that last night to launch its 1984 publication of The Almanac of American Politics, the 11-year-old biographical and technical testament to politics that no student of Capitol Hill would be caught without. All 1,402 pages of it.

"I use the book all the time to check up on customers and make political conversation," said Germaine Swanson, owner of Germaine's restaurant. She may have been the only nonpolitician or nonjournalist there.

"I use it to deal with my colleagues," said Rep. Don Edwards (D-Calif). "It's better than the biographies in the Congressional Directory. After all, we write those ourselves."

"I'm a member of Congress," said Rep. David Obey (D-Wis.) rather succinctly. "Of course, I use it."

Even the torrential rains couldn't keep NBC's Roger Mudd, ABC's Ann Compton, The Wall Street Journal's Al Hunt and the troops from Newsweek, Time and other Washington bureau staffers away from the popcorn and hotdogs that competed frantically for space among the cluttered desks and terminals at the National Journal office.

"You know, it was the first birthday present my husband gave me in 1979," said Compton.

The almanac was conceived by Michael Barone, a numbers addict who was ecstatic at age 7 when he learned the 1950 census figures were out. By 9 he knew how much larger Des Moines was than Peoria.

And by 28 he knew the vital statistics of every congressional district and representative in the nation. The almanac is coauthored with Grant Ujifusa, and is published biennially in batches of 45,000.

"We decided to publish it because it's the best book going," said National Journal president and publisher John Sullivan. "It tells you everything you need to know about politics. Of course, you wouldn't read it cover-to-cover unless you were a wacko."

"I used it tonight, for instance, to look up some congressmen who were expected to be here that I knew nothing about," said Journal chairman Anthony Stout. "So I could find out information like how many Italian Americans in their district."

Who, for instance?

"I can't tell you that," he said. Naturally.

"Well, where are the free samples?" demanded James Lynn, former director of the Office of Management and Budget.

There weren't any. For $35 any number of guests could take one home with a box of popcorn and an autograph from Barone. For $22.50, the paperback edition was available.

"I think I may be the biggest individual buyer around," claimed New York Daily News bureau chief Lars-Erik Nelson. "I give them out as Christmas presents. My mother likes it."