Wonder who owns that mysterious house with the drawn blinds? Can't remember where President Garfield was shot? Got a question about Georgetown's oyster sandwich saloons, or Dunbar High School's 1927 Senior Prom? Call G.R.F. Key, for 23 years the answer man at the Washingtoniana reference desk in the Martin Luther King Library and, at 94, the city's oldest civil servant.

"They're surprised when they first call or come by," the former professor of science and chemistry at Tuskegee Institute says of the people he helps. "First they don't expect to find a man, then a colored man." He pauses and laughs and adds, "Then an old colored man."

But there he is, from 9 a.m. to 1 p.m. each weekday behind the glass walls on the library's third floor. When time allows, he might elaborate and reflect on the subject in question. But more often it's just a few-word answer -- just the facts, no nonsense, especially if he's busy.

"Baltimore and Ohio Railroad Station was where Garfield was shot," he says with his trademark steady delivery and a deliberate nod of his head. "That was on the southeast corner of Sixth and B streets Northwest, eighteen hundred and eighty-one, yes, sir, you're welcome . . . Washingtoniana Division. Yes, sir, we have all issues of Intelligencer, on microfilm, 15 cents per copy page, you're welcome . . . Yes, madam, you'll find out who lives in that house by looking in Lusk's Assessment Directory."

"He's accumulated a vast knowledge. It's remarkable," says Roxanna Deane, Key's supervisor at this repository of all things D.C.

"I don't want to be cocky but there is nothing I don't know about Washington," he says. "These are just things I know."