A Columbia University graduate student who was raped and tortured during 19 hours of nightmarish sadism pointed out Monday the man on trial for the attack as the one who drove her to ask for death and try to kill herself.

Her gaze steady and her jaw tightly set, the 24-year-old woman pointed directly at Robert Williams in court Monday when asked whether she saw her attacker in the courtroom.

The woman identified him as she resumed testimony she had begun Friday to describe an almost unimaginable ordeal of searing pain, degradation and fear at the hands of her attacker.

Williams, a 31-year-old ex-convict who had refused to come to court Friday but was forced to appear Monday, stared straight ahead.

His lawyer, Arnold Levine, agreed that the identification hurt the defendant, although Williams has offered no discernible defense.

"It's always damning when a witness identifies your client," he said.

Levine had no questions for the witness after her direct testimony.

The witness described at least seven instances of rape, sodomy and forced oral sex over the 19 hours her assailant was in her apartment in upper Manhattan.

At one point, the woman testified she was able to grab a pair of scissors the man had made her use to cut her shoulder-length hair to an inch long in some spots.

"I tried to stab him in the neck," she testified, adding that she cut two of her fingers on the scissors' blades. "He grabbed my hand and threw me into the corner."

The witness said she tried to stab Williams because "when he started raping me again, I was sure I was going to die."

"I asked him, 'How does this end?' and he said, 'You know how this ends,'" she testified. "I took that to mean he was going to kill me."

During the ordeal, the attacker also forced her to ingest massive doses of painkillers that caused liver failure, and ordered her to gouge out her own eyes with a butcher's knife.

When she refused, she said he twice threw bleach in her face in an attempt to blind her.

"I was burning all over," the woman said. "He threw the rest of the bleach into my face, but I was able to close my eyes in time. I was breathing it in. My lungs were burning.

"I was trying to pretend that I couldn't see so he wouldn't pour more bleach in my face. I was nearly hysterical. I was shaking and crying."

She said that when Williams started to gather up her things, as if preparing to leave, that was the first time she thought, "I might get out alive," and she started to memorize his features and scars.

Williams later twice poured boiling water over her and sliced her eyelids with the knife, the woman said. Prosecutors showed photographs of her scarred eyelids to the jury.

It was after the second scalding that she asked her attacker to kill her.

"I was screaming and crying and in so much pain and agony," she testified. "I said, 'Just kill me. You know you're going to kill me anyway. Just kill me.'"

But the torturer refused, telling her, "No, you're not good enough for that," the witness said.

The assailant again ordered the woman to stab out her own eyes. This time she nodded her head to indicate she would do it.

"I was in so much pain I decided to aim for my neck, and if I died it would be so much quicker than how he was going to do it," the woman testified. She said she fell toward the knife he had propped up in a pile of clothes, but she missed.

She said this enraged the attacker, and "he hit me with something really heavy." She said she believed it was her TV set or record turntable.

The woman said that after slashing her eyelids her attacker began "beating my face, my eye sockets, with the blunt end of the knife," and she screamed until she blacked out.

When she woke, she was alone in her fifth-floor apartment and tied to the frame of her futon sofa bed. Her attacker had started a fire, and soon she smelled smoke. She moved the futon and saw flames behind it.

The woman said she tried but failed to undo her bonds, so she tried to burn them off. The fire "was spreading really fast," but she was able to break free of the futon frame and run out the front door.

Downstairs she found a middle-aged couple who took her to their apartment building superintendent. He helped her get free of the cords and cables she was tied with, and the other man called 911.

The woman said she was hospitalized 2 1/2 weeks in three institutions, including a special burn facility. After months of physical therapy and outpatient burn treatment, her movement and mobility have returned to normal, she said.