Hogarty laughed nervously. “If this is a joke, I don’t understand it.”

“The Nobel Prize for physics in 2072 went to the man who claimed he discovered time travel.”

“A noble prize?” the man said. “Physics?”

“It’s part of metaphysics,” the woman said.

“I know that. How do you get a prize for it, though? What does it have to do with time?”

“It’s all abouttime,” Matt said, “and space. And energy and mass and quantum states and the weak interaction force. You’re scholars?”

The man touched his scars again. “Of course.”

“Didn’t you ever study any of that?”

“It’s like you’re talking Chinese,” he said. “Quan tong states and interacting forces? What does that have to do with Jesus?”

Matt felt behind him, found a chair, and sat down. “Um . . . Jesus is part of God?”

“They’re both part of the Trinity,” he said. “They share attributes.”

Matt pressed on. “And God is everything?”

The man said, “In a way,” and the woman said, “Everything good.”

“So there are partsof everything that can be weighed and measured, rather than taken on faith. That’s what I’m a scholar of.”

Hogarty was thinking so hard you could hear the gears grinding. “But that’s for craftsmen and tradespeople. What is scholarly about things you can weigh and measure?”

“It’s because of the times he comes from,” Martha said. “The measurable world was very important to them.” She pursed her lips, then said it: “The T word. That’s what it was about.”

“Be good, Martha,” he warned.

“We shouldn’t be afraid of saying things,” she said. “Words aren’t magic.”

“You don’t know, child.” He appealed to Matthew. “Young people.”

Matt didn’t want to go there. “Why do you think measurable things aren’t scholarly, scholastic, whatever? The real world.”

Hogarty smiled, on comfortable ground. “You’re joking again. That’s the Devil’s big weapon.”

“The illusion that this world is real,” Martha supplied. “But not everybody thinks that way.”

“Martha . . .”

“God made this world, not the Devil. In six days? The actual world itself isn’t evil.”

“She’s an independent thinker,” the man said, not quite through clenched teeth. “An excellent graduate assistant for you.” Church bells were chiming outside. “Noontime. I have to meditate and break fast. Martha, you will see to the professor’s needs?”

“Of course, Father.”

“Professor, I’ll come by your office Wednesday morning sometime. There will be a faculty meeting in the afternoon. ”

“My office?”

“Martha will find you one. Tomorrow, then.” He left with the haste of someone really looking forward to meditation.

“So . . . how are you going to find me an office?”

“They gave me a list. But four of them are small. I know the one you want.”

“Okay. So who are ‘they’? How come they knew I’d need an office?”

“The administration. I had a note this morning saying I’d be assigned to you, and to expect you soon. Then Father Hogarty came by and said you were here in the library.”

“But the administration, they knew about me yesterday? ”

She nodded. “Somebody knew you’d need an office. Maybe they knew your building was gone.”

All that from the casual encounter with the guard in Building One? It occurred to Matt that it had probably been a robot, too, and he’d been scanned and identified.

So who knew what around here? He was in a database as a scholar, even though he was last employed 177 years ago.

Did that mean someone was expecting him?

He followed Martha up three flights of stairs to a dim corridor. She gave him a brass key. “This is a nice bright one.” She pushed the door open with a creak.

Well, it was bright enough. It should have been in the shadow of the Green Building, but instead he looked down on the roofs of low wooden structures. No sign of the building or its venerable Brancusi sculpture.

But just a couple of days ago, he’d snatched the time machine there and commandeered a cab and come here.

“Professor? Don’t you like it?”

“It’s fine, Martha. I was just looking at where my old office used to be. The Green Building.”

She looked out the window. “It’s not one of those?”

“No, a lot bigger. You don’t have any pictures of what it used to look like here?”

“Of course not. Nothing before Jesus.”

“Because it’s a sin?”

“No,” she explained patiently, “because it was before.”

“All the pictures from before just disappeared?”

“Oh, no. We have Rembrandt and Leonardo and all those men. I like Vermeer best; there are two of his downtown. ”

Not very religious, a reassuring characteristic. “No photographs, though—nothing from my own time?”

“That all disappeared when Jesus came back.”

“What, it just went poofinto thin air?”

“That’s as it is written. Angels took it all away. I wasn’t there, of course.”

Like Billy Cabot’s Avenging Angels? “I have a lot to learn,” Matt said, “before I can think of teaching anybody anything.”

“I can help with everyday things,” Martha said. “Father Hogarty said you won’t be teaching this semester.”

“Glad to hear it.” There was an old metal desk to the left of the window. Matt went through the drawers and found a small stack of paper, two pencils, a dip pen, and a bottle of ink. Next to it, a cylinder of cloth obviously used as a pen-wipe was rolled up around a small knife and two extra pen points.

She picked up the two points and held them up to the light. “Somebody hasn’t been too careful. I’ll bring you a potato.”

“All right. Why a potato?”

“It keeps the points from getting rusty. You stick them into a potato when you’re done for the day.” She had the amused patience of a graduate assistant telling the professor how to turn on his new computer. “You didn’t have pens like this.”

“Actually, I’ve only read about them. Ours carried their own ink around.”

“I’ve seen those. The dean has one, his pen-stick. May I show you how this works?”

“Please.”

She pulled out the old desk chair, which was on wheels that didn’t roll, and sat down carefully. She treated the ink bottle with care approaching reverence, holding it tightly while the top unscrewed with a rusty squeak. She showed him how to dip the pen partway and remove the excess ink by sliding the nib left and right along the rim of the ink bottle. Then along the top of a piece of paper, she wrote, “Jesus died to save us from our sins” in a careful hand. Matt remembered the tollbooth’s crudely lettered BOSTON CITIE LIMMITS / PAY TOLE ONE DOLAR and wondered how rare her talent was.

She stood up and handed him the pen. “Would you like to try it, Professor?”

Not really. He sat down and tried to duplicate her motions. In block letters, he printed THE QUICK BROWN FO, and ran out of ink. The letters were wavering and blobby.

“A brown fo,” she read. “Is that like an enemy?” He completed the line, dipping the pen twice. “It sounds like the start of a parable, or a fable. The fox is quick and gets away?”

“It’s just a nonsense line. It uses every letter of the alphabet. ”

“Oh, like, ‘Jesus up on high rules few vexed crazy queers today.’ ” She laughed behind her hand. “The sister who taught me that in school was reprimanded. So I memorized it.”

“As you told Hogarty. Words aren’t magic.”

“Only some of them, in the right order.” She took the pen from him and wiped it with the cloth. “Always—” Someone knocked on the door. “That would be your midday. ”

She opened the door and a male student handed her a wooden tray covered with a black cloth. “Thank you, Simon. ” She set it on a small table by the door.

“Professors don’t eat with the students. I took the liberty of giving the kitchen this room number, but you might prefer to have it sent to your quarters.”

A long way to Magazine Street, he thought. “We’ll go find your quarters this afternoon,” she said. “I’ll be out of class at three. May I meet you here?”