Beneath Dupont Circle, Mark Chase sits in an octagonal glass booth and looks beyond his reflection at the columns of commuters passing through his subterranean world.

Not too long ago, Chase recalls, he was behind the wheel of a Washington Metrobus, fighting traffic and defending himself against occasionally violent passengers. Last year, with 14 years of seniority in the system, Chase, 37, qualified for one of Metro's coveted positions, a kiosk attendant, and went underground.

"To me this is like dying and going to heaven," he said.

The kiosks offer relief from road and rail. Many of them shelter older or injured employes, Metro officials say. But station attendants favor their jobs for more than comfort. They describe themselves as the grease in the Metro machine, the human antidote to automation, and they take pleasure in easing people's passage through the system. Sometimes, they say, the job can be more demanding than passengers understand.

"A lot of people think that this is an easy job, and it is in certain respects. Sometimes we sit down here and it looks like we're not doing much," Chase said. "But then, in a 15-minute span, we've done eight hours of work," he adds, and the next hour of activity underscores his point.

Chase spins in his swivel chair to attend to a small crowd of confused, impatient travelers at the door to the kiosk and the window at the opposite end. The questions repeat themselves like songs on a Top 40 radio station.

"How do I get to National Airport?" asks a young man laden with luggage. "How do I purchase a fare card?" a middle-aged woman clutching a collection of maps inquires. "What is the fare to Foggy Bottom?" two teen-aged girls en route to Georgetown wonder.

The answers require no hesitation, but the crowd grows. Most of the information the Metro riders require is spelled out before them in black and white, red, yellow, and blue, but they regard Chase as a simpler or more reliable source.

They complain when the turnstiles reject their Farecards -- and walk away embarrassed when he tells them they must add more fare. Few passengers argue with the verdict of Chase's computer, which reads the magnetic strip on the Farecard and tells him its history.

Periodically, Chase glances at a panel of video monitors that enable him to keep an eye on the platforms and the tracks. He must respond instantly if someone wanders into harm's way.

The responsibilities of Metro's 295 station managers are to keep the equipment functioning at the system's 64 stations and to assist passengers. Some managers might fall short of the public's expectations, but others go beyond the call of mere obligation, employes say.

"We have two {types}: what we call the kiosk manager and the station manager," said William H. Burriss, a 52-year-old former bus driver who was working at the Arlington Cemetery stop this week.

"The kiosk manager sits in that chair. If somebody wants something, he sits and he points. The station manager is on top of everything that's going on in his station. The best to be is the station manager," Burriss said.

His voice echoes faintly in the empty corridor. When the throngs of tourists subside, the cemetery stop is one of the quietest on the line. Some of the more senior atten ants elect to work there to escape the bustle that marks other posts.

At the Pentagon station, Willie Houchens is busy being a station manager. It is midday, and crowds of uniformed military personnel press through the turnstiles on their way downtown to attend the dedication of the Navy Memorial. A train is late, a Farecard machine is malfunctioning, and half a dozen people are having problems entering or leaving the platform with their cards. In a matter of moments, Houchens calls for a backup train, summons a technician and writes out a trip pass for a passenger whose problem defies a quick solution.

From time to time, he will give stranded passengers money out of his own pocket to ride a train. People often forget their money at home, he notes, and others leave in the morning with just enough money to get to and from work. Helping them is part of the job, he says, and the people he helps invariably pay him back.

Houchens, whose bad back forced him to give up his driver's seat, would rather be busy than bored. He still shudders at the memory of long shifts spent in relative silence at the Courthouse and Judiciary Square stations.

"You would read every sign, every book the company would put out. You'd know them by heart. By the end of the day, {the station} got smaller and smaller and smaller. To me, it felt like a jail," he said.

Metro rules prohibit attendants from reading novels or watching television in the kiosks, employes say. But one of them concedes that during the late hours, when only the squeal of train brakes punctuates the quiet, he escapes into fiction.

Metro workers say the job includes its share of indignities. Disgruntled passengers commonly unleash their frustration on the man or woman in the booth, who is expected to defuse the situation rather than respond to personal insults, they say. And often, passengers complain about attendants when the problem at hand is beyond the attendants' power to remedy.

Paul Davis, who was working the morning shift at McPherson Square, remembers the rider who struck him with a carpenter's saw. "He lost his dollar bill in a vendor and he kept insisting that I was going to give it to him." Davis escaped serious injury.

Company regulations sometimes get in the way, attendants say, and they must improvise to move passengers along. One station manager displays a cache of lost or discarded Farecards, many of them still valid, that he hands to stranded passengers, he says.

"We bend the rules an awful lot. If we went strictly by the book, there would be people backed up every morning," the attendant said.

Station attendants are paid just less than $30,000, 5 percent less than drivers and train operators, plus overtime. They say the greatest satisfaction on the job comes from meeting strangers, however briefly, and helping them on their journeys. Asked to recount their most memorable experiences on the job, they tell of retrieving lost purses and turning scowls into smiles with a friendly word.

And then there is the occasion when an able station attendant can make all the difference. David Merriwether remembers the day five years ago when a blind man with a guide dog passed his booth at Judiciary Square. The dog and the man tumbled over the edge of the platform, and Merriwether, who was keeping a close eye on his monitors, rushed to their rescue.

Merriwether cut the power before either touched the deadly third rail and before a train pulled into the station.