“Well then, doc, what I’d like you to do is go over to Trinity Church. There may be some folks over there that need attention, and I believe some of my boys are there too. Would you do that?”

“I’m on my way.”

He went outside onto Liberty and started south down Broadway, glad to have something to do. He’d better call his wife to let her know he was safe. She could call the office. And while she was at it, he suddenly thought, why not call the realtor and tell her they’d changed their minds about that damn Park Avenue building. He didn’t want to live there any more.

It was nearing ten o’clock. What could be taking her so long? Gorham stared at the tower. While the flames were still burning brightly up in the North Tower, the South Tower seemed to have settled into a smokier, more sullen mood. Several times he’d heard explosions from lower down in the towers. Stores of gas or electrical equipment? Or perhaps, he guessed, fuel from the planes might have run down the inside of the buildings, collected again, and suddenly exploded. Who knew? But whatever the causes of these other sounds, it was smoke rather than flame that was to be seen issuing from the South Tower now.

Almost ten o’clock. Surely she must appear any second now.

His cellphone rang.

“Hi, honey, it’s me.”

“Thank God.”

“That was a bit of a journey down.”

“Maggie …”

“What’s up?”

His eyes were fixed on the upper part of the South Tower. Something was happening. The top seemed to be leaning, twisting.

“Maggie, where are you?”

Now the tower seemed to be righting itself, but only because further down, something had snapped or shifted. For suddenly the roof of the great tower was beginning to sink.

“It’s okay, Gorham. I’m down, and—”

“Maggie—”

Nothing. Deadness. The top of the huge tower had started to travel downward. He had never seen anything like it, except in movies, or old newsreels. The controlled demolition of high-rise buildings. It was amazing how they could just sink, like a collapsing concertina. And that was what was happening now. The South Tower was falling in on itself.

But so slowly. He could not believe how slowly. Second by second, as if in slow motion, the tower was traveling down. One second, two seconds, three seconds, four … With majestic, deliberate, measured speed, the top was sinking while, at the bottom, with a slow roar, like a groaning waterfall, a huge, grayish cloud of dust was belching out.

“Maggie.” No voice.