In a world suddenly turned sideways, Dolores Gunderson`s grip was failing her.

Gunderson, 56, lay on the inclined floor of an `L` car, clinging to the legs of the seat that she had been sitting in only moments before as the Lake- Dan Ryan rapid transit train rounded the corner at Wabash Avenue and Lake Street. The front end of the twisted, toppled train car was resting on one of the beams supporting the track superstructure; the other end of the car had fallen onto the pavement below.

"The car was sort of dangling," Gunderson, who has since retired as an advertising agency employee, recalled recently. "I had been sitting at what was the front end--the end that was being held in the air by the beam."Before long, a savior in blue appeared.

"A policeman came in through what was the top end of the car," she said. "I had been hanging onto the legs of the chair. It was like hanging onto the side of the mountain. I was getting awfully tired--I was sort of numb --and I started to slide down.

"He wanted to take me out through the top, but I was afraid to go that way. So he held me and, ultimately, the two of us sort of slid to the other end of the car. He was so cute. I never knew his name, but he was trying to comfort me, kissing me on the cheek and telling me everything was going to be all right.

"Then he told me, `We`ve got to stop meeting like this.` "

By the time authorities had sorted things out that fateful Friday afternoon, Gunderson`s brief and unscheduled trip down the aisle would prove to be part of a longer date with destiny.

To most everyone who was in Chicago at the time--and to many across the country--the basics are more or less familiar: Feb. 4, 1977; four cars of an elevated train that tumbled 20 feet off the track; 11 dead, 183 hurt; the worst elevated train accident the Chicago Transit Authority has had.

But now, a decade later, tragedy has been transformed into mere history

--a "remember when . . ." that people bring up over beers and then push aside for something more pressing.

To those who were on that train, however, and to those who witnessed its fall, almost all of the incident remains vivid. Some, like Gunderson, remember moments of horror and humor. Some recall details improbably minute amid chaos of such magnitude. Still others, including several contacted for this article, choose even now to keep their thoughts private.

A reporter at the time called the crash a "freak of physics"--a peculiar combination of forces that created a catastrophe out of what in other places, at other times, would have been a routine derailment.

Far more freakish, though, is the fact that one of the few people in Chicago who could have understood what was happening saw it all.

An electric-train enthusiast since childhood, Donald MacCorquodale on Feb. 4 was putting in volunteer time as a public relations man for the Central Electric Railfans` Association. With an office in the building at the northeast corner of Lake and Wabash, the group, among other things, publishes a catalogue of books pertaining to electric trains.

A man in Argentina had sent an urgent order for a General Electric book called "Electrification," and since it was about 5:20 p.m., MacCorquodale had missed his building`s last mail pick-up. At the southeast corner, though, there was a mailbox with a 7 p.m. pick-up.

"Let`s put it this way," said MacCorquodale, who is now 42 and curator and vice president of the Fox River Trolley Museum in South Elgin as well as a marketing consultant. "The `L` train got to the mailbox about 60 seconds before I did--and I had to wait for the light to change." Despite his expertise, MacCorquodale did not speak to reporters that day. He reserved his comments for investigators.

While waiting, he said, he heard the rumble of a train and looked up. Perhaps, he thought, it was one of the new 2400 series of cars that the CTA was testing on the Lake-Dan Ryan line.

"Instead," he said, "I saw this." The eight-car train had bumped the rear of a Ravenswood train on the tracks ahead.

"Apparently after bumping the train ahead of him the motorman panicked and turned his controller to power. He had the full tractive force of all these `L` cars behind him, so you got the effect of a watermelon seed being squeezed.

"The train was lodged against the back of the Ravenswood, and it alternately rocked outward and then back inward about three times, and each time it drew this tremendous arc."

Gunderson, who was sitting inside the second car, recalled: "We were being whipped back and forth, like at the end of a whip almost. The car was being shaken like a toy. That`s when I fell to the floor and somebody

--accidentally, of course--stepped on my head."

MacCorquodale said: "On the fourth rocking motion, (the first four cars) just went all the way over and fell into the street. It was an almost slow-motion event. It was not a split-second event. You could really see all of this happening.

"Throughout all of that I can tell you there was sort of this feeling of unreality, that it just wasn`t happening."

A technical detail brought the reality of it to MacCorquodale: "On the roof of the 2000 series of cars, which were the lead pair on the train that fell off, there is an air-conditioning hatch. Seeing that hatch come into view made me realize that `My God, it`s coming over, and there`s no chance that it can stay up there on that track.`

"After the train fell, there was this very strange experience of almost complete silence. After this tremendous uproar of the train hitting the street, it was almost deathly quiet."

Inside the third car, which hit flat on the pavement instead of balancing on the support beams, Kathryn Garrison was wearing a fur coat that her husband, Stan, had bought for her a couple of years earlier in Greece. "This is the thing that she always believed saved her life," said Stan Garrison, now 59 and a recent widower. "It was the thickness of the fur."

Ray Komorowski and Peggy Del Vecchio were young, in love and riding in the first car.

"I had never been on that train, and was afraid of going around that turn," said Ray, now 32 and an engineer. "She always said, `There`s nothing to be afraid of.` And the one out of a million times there was, I happened to be on that train."