TWENTY-FIVE YEARS ago this Monday, President Richard Milhous Nixon, facing certain impeachment and conviction by a bipartisan majority of Congress, resigned in disgrace over the Watergate scandal.

It is odd for me, a reporter who covered that scandal for two solid years and whose life was dominated by the story, to run into people today who have little or no memory of what arguably was the greatest political scandal in our history. I can forgive college kids who weren't even born when a band of burglars, financed by the Nixon reelection campaign, was arrested in the humid pre-dawn of June 17, 1972, after having broken into the Democratic Party headquarters in the Watergate office building in search of politically sensitive documents.

I can understand if they don't know that Nixon entered into a conspiracy to obstruct justice by ordering hush money paid to the Watergate burglars and by deliberately using the FBI and other federal agencies to thwart the Watergate investigation.

But what really galls me is when people my own age are clueless about all this. Which makes me urge you to run, not walk, to the National Museum of American History to see a remarkable visual chronicle of the turbulent Nixon years.

The show is titled "Photographing History: Fred J. Maroon and the Nixon Years -- 1970-1974" and provides a telling look, not only at images that are, by themselves, historic, but also at images that have never been seen before. Through a happy mixture of persistence, skill and luck, Maroon was able to make a behind-the-scenes portfolio of the men and women who were in the bunker with Nixon during that wrenching time. It is a fascinating look at history by a first-rate shooter: images of a scowling Nixon that look almost like caricature, intimate shots of Nixon honchos John N. Mitchell, Charles Colson and others huddling over who knows what? There are even a few funny shots -- of a decidedly unglamorous Diane Sawyer in heavy black horn rims, working at the time as an assistant to Nixon press secretary Ron Ziegler. Look closely at another shot, of some earnest members of the Watergate prosecution team, and you'll barely recognize a young Hillary Rodham Clinton.

So how did this come about? As with many things in life, indirectly.

When Nixon took office in 1969, Maroon was a sought-after freelance magazine photographer, who had done a number of large layouts on the Kennedy White House for the old Look Magazine. He had hoped to do the same in the Nixon White House, but soon encountered twin roadblocks. Many of his editors displayed little interest in such a story about the dour incoming president, and Nixon himself was loath to have a photographer wandering at will in the White House. Maroon was able to get permission to shoot pictures for a book on the workings of the White House staff (Washington novelist Allen Drury did the text) and that project won him access to shoot behind the scenes at the then-newly formed Committee to Re-Elect the President. The initials were CRP, but almost everyone called it CREEP.

(An interesting technical sidelight. Fred got access, not only on the basis of his skill and reputation for fairness, but also because he was quiet as a mouse. Much of his work was shot with available light on Tri-X film, with M-series rangefinder Leicas, arguably the quietest cameras in the world. Fred's equipment, as well as many of his contact sheets are on display at the museum and provide a fascinating look at how a photojournalist works.)

"While I was working at the CRP in the weeks immediately following the Watergate break-in," Maroon writes in the preface to his show's handsome catalogue, "a discernible pattern developed. I would be allowed to photograph a meeting for ten or fifteen minutes and then I was always asked to leave. I can only imagine what key conversations must have taken place the minute I was safely out of the room."

In subsequent months, as the Watergate scandal unfolded, it became clear to Maroon that his work was an important historical document. He canceled all other assignments so he could cover the drama of the Senate Watergate hearings in the summer of '73.

"In August 1974 my project ended where it began -- in the White House. It was a far cry from the days of 1970 and 1971. During the week leading up to August 8, when President Nixon announced his resignation, uncertainty and apprehension prevailed. And the dramatic moment in the East Room the next day, when the President mustered up the strength and determination to say goodbye to his staff, cabinet and friends, was like nothing any of us expected to experience."

But experience it he did, and Fred Maroon came back with the pictures.

The show runs through Dec. 5.

Questions or comments? Write me c/o Weekend, The Washington Post, 1150 15th St. NW, Washington, D.C. 20071 or via e-mail at fvanriper@aol.com

Next week in this space: Stamps columnist Bill McAllister.