Spend Saturday night on the subway, they said. Find out where people are going and why they're going there. And make sure that something happens. If you need to get mugged to get a story, get mugged.

Those were, more or less, the instructions. Here is what did not happen:

"It was late. As the train pulled into Washington Street Station, the wino clutched the neck of his brown paper bag and lurched through the door. I realized with a quick chill that I was alone, totally alone. Suddenly, as the doors slid shut, a trio of leather-jacketed, acne-scarred youth darted onto the train. The stench of beer and sweat and corruption filled my nostrils. As one of the toughs sprawled insolently across a seat, another flicked his switchblade open and shut in dull, menacing repetition.

"Then he noticed me..."

No muggings, no hijacks, no escaped lunatics. But the Boston subway as Saturday evening entertainment turned out to have its advantages: cheaper than a drive-in, warmer than ice-skating, and more conducive to intimate discussion than a freshman mixer.

At the Harvard Square station, David Hershey-Webb ("pretentious name," he apologized) told me has cut short a planned evening of guitar-playing, singing and coin-collecting in front of the Coop to go to a party at the Commonwealth School, a progressive private school in a Back Bay townhouse. "I went to school there last year, and I'm going to go there again next year," Hershey-Webb said. "This year I'm taking a sabbatical at a Boston public high school so I won't be a private schoolie like her." He pointed to the girl sitting next to him. She did not smile or seem insulted, but acknowledged that she went to Commonwealth and said that her name was Deborah Alkema. Like Hershey-Webb, she had long blond hair and wore jeans but unlike him she sported no Udall button.

Hershey-Webb went on. "The school I'm at now is really terrible. It blew my mind. There are seniors who can't read. If you can't read, you're nowhere. What they do all day is beat people up." Hershey-Webb said he was "trying to reform the place in my own quiet way." So far his campaign had involved writing a letter to the school paper, explaining why "their methods of teaching are wrong, and their attitudes are wrong." "Anyway," he said, "it's an experience, and that's what I wanted." He and his friend got off on the right side of the train at Park Square, and I got off on the left.

At Park Square, a woman was waiting for an Ashmont car with what looked like a stewardess outfit folded neatly over her arm. She said her name was Pat and she was not a stewardess, but a guard for American Airlines. The insignia on her uniform said SECURITY '76.

For the last 16 months Pat had watched boarding passengers walk through the X-ray machines. She liked the job, she said, because there was always something going on and interesting people to see through. Just a few weeks ago, she said, Cliff Robertson had been at Logan. When pressed for an evaluation of Robertson's sex appeal, Pat admitted that only her sister had seen him, and that she hadn't even known who Robertson was. "But a while before that, one of Ford's sons came by," Pat said. "He walked through the machine like everyone else, even though he didn't have to."

Pat craned her neck as a train approached, but it was the wrong one. "Lord, I hate the subway," she said.

Upstairs the platform was almost empty. A uniformed T worker with a bullhorn had just announced to a small band, including a forlorn David Hershey-Webb, that a derailment at Copley Square had broken all Green Line service as far as Kenmore. Above ground, a confused crowd waited for buses. The overland route brought us to Kenmore Square, where another disgruntled crowd milled about. Across Beacon Street, in the Relax-A-Bit coffee house, a streetcar driver sullenly sipped coffee. He looked as gloomy as if he had driven the streetcar off its track himself; perhaps the derailment meant he would have to work late.

I took the stool next to him at the counter and greeted him.

"How'd it happen?" I asked cheerfully.

The man didn't look up from his coffee. "Don't know. Just got on duty now."

"Ahhh. That's what he says," a strange voice said.

I turned to my left and saw a young man with very long black hair and glazed, demonic eyes. He was snickering into his coffee, drops of which dribbled down his straggling beard. "Don't know! Don't know!" he mimicked nastily. He sniggered some more.

The T worker glared at him. Behind the counter the waitress asked the driver how he wanted his steak. "Christ, any way," he said, and wheeled his stool to show his back to both of us.

"Cheer up," the bearded man said. "Everyone makes mistakes."

"I don't know how the fucker could have done that," the man said. "I've been working on this line for 28 years, and I don't see how it could have happened." The old conductor's voice echoed in the tunnel between Copley and Auditorium. In the dimness before us the streetcar splayed incongruously across the width of the tunnel. Emergency workers hovered about it uncertainly, shook their heads, spat, conferred in short spurts of strategy. Occasionally they would seek advice from the telephones that seemed to grow out of the cave walls. In the dark unfamiliar tube the men spoke softly, as if not wanting to disturb an accident victim.

A supervisor came and hustled me back to the station platform. "We won't know why it went off until we get it back on," he said absent-mindedly. "Just tell your readers that service will resume in half an hour or so."

The orange line was quiet and people were glad to talk. A young black man had just come from heavyweight wrestling at the Garden, where he had been impressed by the performance of Bugsy McGraw. "The whole thing is phony," he told me, "But it's great entertainment. I go once a month, and never miss it on Saturday morning T.V."

Charlie, a stout, perspiring private cop who works at Logan, said that his job there was "to guard the stewardesses," and he winked. Then more soberly he said that most stewardesses are respectable married women and that "only 25 per cent or so are quote unquote The Stewardesses." Charlie would like to be a steward for Delta, but he said he is not sexy enough to get the job.

A polite, middle-aged, slow-talking gentleman cornered me to discuss his model train collection. I escaped off the train and down a long dark passageway which led to the red line and a Quincy train.

I got off at Quincy Center, last red line stop. Four or five blocks from the station I came to the Oyster House, fine food and drink. In the dimly-lit bar a dozen customers were enjoying the fine drink. No one ate oysters.

A color movie flickered unwatched across a large screen on the right-hand side of the restaurant. The drinkers sat with their backs to the film, while Al the bartender, a skinny man with tremendous ears, told stories and teased his regular customers. I squeezed onto a barstool between a large Lite drinker and a large Schlitz drinker and asked the name of the movie.

"More of the hippie bullshit," the bartender grinned. "Strawberry Statement, something like that. You ought to know all about it." His ears wagged as he laughed, and the Lite drinker on my left smiled appreciatively.

No offense intended, though. As a peace gesture the bartender gave me a story along with my Bud. "Six or seven years ago it was," he said, "I bet four bucks on the twin daily double at Rockingham. It came through, only for eleven dollars. Eleven goddam dollars! I know a guy who won five grand on a four-horse birdcage." Al said he was so disgusted he just tore the tickets up.

On the screen some clean-cut radicals were holding their arms up against a wall waiting to be frisked. Al and the Lite drinker on my right discussed Hank, an old jockey.

"Wasn't he in the hospital a while back?" Lite asked.

"Yeah, that's right," Al said. "Fell off his horse and got run over."

Lite shook his head. "Where is he now?"

"He isn't," Al chuckled. "He died a week later." Someone called for another Miller and Al strolled down the bar. Pasteurized rock music leaked from the screen.

I left Oyster House in time for the last train to Harvard. Between Wollaston and Park I had the train to myself. Now was the time for the punks to appear, but the train rollicked on peacefully. At Park Station the Cambridge couples began to fill the car, back from the movies, from dancing, from dining out. By the time we reached Harvard Square the train was quite full. The station's usual urine smell was mixed with marijuana and perfume, it being Saturday night.