Driving down Wisconsin Avenue on Friday, having passed through a downtown Bethesda that has become thoroughly high-risen in its structures and then approaching an equally startling metamorphosis at Friendship Heights, I remarked to my companion that no Washingtonian of, say, 30 years ago would recognize the place.

Yesterday, under improbable circumstances, I met that former Washingtonian. It happened at the Rosslyn subway station about 1:30 p.m. when all the turnstile gates in both directions were flashing a red message: Do not enter.

Since no attendant was in the kiosk, I walked through the emergency gate and was headed for the escalator when somebody who had observed me called.

"How do you get on the train?" he asked, as dozens of people, in both directions, sought to get either into or out of the station. None seemed to want to avoid paying fare. Extralegally, the best advice was for arriving passengers to exit via the emergency gate and for incoming passengers to enter via the same gate and explain the situation to the station attendant at the other end of the trip.

Anyhow, the fellow who asked my advice turned out to be Harold Hicks of Shreveport, La., attending a reunion of military aircraft controllers from World War II and the immediate postwar period. He said he lived from 1950 to 1954 at Andrews Field, now Andrews Air Force Base, in suburban Maryland and now finds "high-rise buildings, traffic, a lot of new buildings" and the subway to be confusing elements, though the latter is useful.

A friend of his, Bill Schuster of Denver, was stationed about the same time at Bolling Field in Southwest Washington. At the time, Schuster said, he considered himself an equal to a Gray Lines tour guide in the knowledge he had for showing guests around town. In today's Washington, he concluded: "I'm a hick . . . . I'm out of date."

Anyhow, by the time our conversation ended, Metro's Rosslyn station attendant, Walt Neishell, showed up and keyed the gates so both incoming and outgoing passengers could pass through. He said the problem had been triggered by a brief power failure during his 30-minute lunch break. On weekdays, but not on weekends, Metro has backup personnel at the busy station.