Chapter 0

[Alexandria, 413 AD]

Sierra walked quickly past the Library in Alexandria, sandals slapping on stones.

No clocks were on its walls. But if there had been an hour hand and a minute hand, in alabaster or some other white mineral that matched the walls, she knew the minute would be pressing the hour, and the hour would be twelve. The Library was at its end–

"Hypatia!"

She turned around. "Synesius, an unexpected pleasure! You should have sent word. Ptolemais to Alexandria is a long way to travel for a surprise visit." She knew he was desperately in love with her, in need of her, especially after the grievous loss of his wife and two boys. She cared about him, but was in love with no one likely alive in this ancient world.

"The winds were kind. I boarded the ship four mornings ago, and here I am."

The sun had just set behind him. Synesius was about the same age as Sierra – he would have been about ten years younger than the original Hypatia. He had been Sierra's student for an intense year, shortly after she had first replaced Hypatia, who had died of a swift fever. Today, Synesius looked older than both of them put together. Dark pouches anchored his eyes, deep creases mapped his forehead.

"What is wrong?" she asked him, though she could think of a dozen things.

"People of my faith are angrier than ever about you and your pagans. I am concerned about your safety."

Sierra scoffed. "Why, if you have such confidence that yours is the one, true, inevitable faith, do you have such anger towards others? Surely, if your faith is right, all others including mine will fade of their own accord."

"Not all of us want to kill you," Synesius replied. "I certainly do not." He blushed, slightly. "Most of us indeed believe that in time the whole world will be Christian. But there are fanatics among us – Nitrian young men – who see their mission as cleansing the world of all impurities, immediately, and these include the purveyors of impure thoughts. Your beauty and intelligence make you the most dangerous purveyor of all. They burn with hatred – I have seen it."

Sierra turned from Synesius and the colors behind him and looked again at the Library. It was bronzed and dignified in this light. "My father did his best to stave off the bloodshed, to contest with ideas not knives, but he lost that battle." She was talking about Theon, who was Hypatia's biological father, not hers. Theon had succumbed to the same fever as Hypatia, which had cut short Sierra's attempt to locate the cure for Socrates's illness. But when Hypatia's death was imminent, Sierra had taken some of Hypatia's DNA, travelled to Athens and the future, and reconstructed her face and vocal chords so that she looked and sounded like Hypatia. Sierra returned and took Hypatia's place.

For the Alexandrian world of 410 AD and all subsequent history, Hypatia had recovered. If she looked slightly different, if her voice sounded off, that was ascribed to grief over the loss of her father and her own close encounter with death. . . .

Unfortunately, that same history had Hypatia dying by vicious assassination in 415 AD. But that was still nearly two years away. Sierra had crucial work to do, but no intention of staying in Alexandria that long. But what, then, was the cause of this visit from Synesius today? Some cloaked danger that her reading of history had not disclosed?

"Your father was a wise man, as you his daughter are wise," Synesius said. "Indeed, you are wiser still – you have an understanding, a perspective, that speaks of centuries, not just years."

"Thank you," Sierra replied. "A high compliment from the Bishop of Ptolemais."

"Yes, a compliment," Synesius said, "but a warning, too. In return for your wisdom and the awe you evoke in people, you court death from the Christian fanatics."

"What would you have me do?"

"Leave with me," Synesius said. "Come with me to Ptolemais. There is nothing here for you now, just scrolls and memories. You can take the memories with you. And the scrolls are dwindling."

"I am devoted to saving them, and to stemming the exodus of scholars from Alexandria," Sierra said. And finding the cure for Socrates, if it exists. She had deliberately come back here near the end of Theon's life, in case he had not learned about the cure until his last years. But she had not counted on Hypatia dying at the same time, and now she was obliged to pursue this phantom cure without their assistance.

"Come with me," Synesius repeated. "You will be safe in Ptolemais. Under my protection. I will care for you."

Sierra reminded herself that, in this age, bishops were not celibate. "No," she said. "The Library requires – and deserves – my attention." But it wasn't just Synesius's desire that she wished to avoid, nor the dwindling holdings of the Alexandrian library that she yearned to protect, nor the possible cure for Socrates that she wanted to find. Alcibiades was long overdue in Alexandria.

"Very well." Synesius lowered his head in acceptance of Sierra's decision. "I will spend the night with my brothers – at quarters generously provided by Marcellinus – and leave for Ptolemais in the morning."

"Marcellinus of Carthage? Your importance has grown since the last time we met. That makes me happy." Marcellinus was not only Proconsul of Africa but speaker for the Emperor himself. But she also knew that Honorius ruled only over half an Empire now, and the weaker, crumbling half at that–

"If only my importance were enough to convince you." Synesius reached into his robe, and extracted a small bundle of scrolls. "These were recently recovered in a house that the Nitrians set on fire. They were written by your father."

* * *

Sierra looked up at the pastel ceiling of her bedroom in the Library late that night, and shook her head, slowly. . . . But if Alcibiades was coming here, why wasn't he here already?

Where was he? She asked herself this question every night, as she lay tossing and turning, waiting for sleep. She could put it out of her mind, barely, sometimes, during the day, but not in the night. She looked at the little digi-locket she had picked up in the future and now kept by her bed. It was a painting – by Jean-Baptiste Regnault from 1791, "Socrates Dragging Alcibiades from the Embrace of Sensual Pleasure". A stern Socrates dragged a young fair-haired man from a blonde woman. Nothing about the picture was right. Socrates of course looked nothing like Socrates, Alcibiades bore no resemblance to the real man, and she in all her disguises had never been blonde. But someone, something, had dragged him away from her. . . .

Was he waiting for the time closest to her advertised death – the time of Hypatia's murder as recorded in history – so that he could show up at the last minute, and be sure she, Sierra playing Hypatia, was here?

A very dangerous game, but she was playing it, too. Attracted like some fluttering insect to this hot Venus flytrap of a place and time. And why?

For Alcibiades? Yes.

For finding the elusive cure for Socrates, if it ever existed – even though Theon, its reported author, was gone? Yes. Even though the biblia Synesius had given her today had proved to be another dead end, containing nothing new, at least on her first, heart-thumping read.

She thought about those scrolls – and then about all the scrolls still left in this Library. She picked up a scroll she had left near the side of her bed. It was by Alcman of Sardis, a seventh century BC Spartan. He and his poetry were known in her future age, but this work was not. It would not survive the final destruction of the Library by the Caliph Omar some two hundred years from this past.

But Alcman and his world of potential readers were the lucky ones – at least some of his work had endured. Most books that survived into the age of the printing press in the West – the world of Gutenberg in the 1450s and the mass copies it would produce – were home free. Certainly everything that had made it into her digital age in the twenty-first century would likely be available to please and inform and infuriate readers for as long as there were humans on Earth and other planets.

But what of those ancient authors whose very names became soot in the burnings of Alexandria? She had encountered many of their scrolls back here. She thought of another poem – Thomas Gray's "Elegy in a Country Churchyard" from the 1700s – and its paean to the "mute, inglorious Miltons" who were buried in the graveyard, great poets and thinkers whose works had never made it to the light of day and publication. How many mute, inglorious Homers and Platos lay in the halls outside her room, not mute and unknown now, but soon and irrevocably to be?

No . . . nothing was irrevocable when it came to time travel. . . .

* * *

She heard familiar footsteps in the hall as she perused an unknown variant of Aristotle's Politics early the next morning – who knows, it could have been a copy of one of the scrolls from Aristotle's famed personal library itself, said to be the seed of this great Library of Alexandria.

The steps were too slow to belong to Synesius. She carefully re-wound and returned the scroll to its compartment.

"Hello," a kind voice said to her. William Henry Appleton looked worn. This was the third trip the great publisher had taken back to Alexandria. But he was here, Sierra knew, on behalf of friendship, not business or scholarship. He was probably the best friend she had, in this or any time.

"When you go back to your family and home on the Hudson this time, you should stay with them," she told him, tenderly.

"I wish I had better news for you, my dear. There is no sign of Alcibiades anywhere. It is as if he entered a realm of invisibility when he left the Hippocrates Medical Center that morning in the future."

Sierra nodded. The unhappy news was not unexpected. "Have you eaten?"

"Yes," Appleton replied. "One of the Library staff was good enough to fetch cheese and fruit for me." He patted his stomach. "I think your staff are getting to know me! The food was quite good!"

"I'm glad," Sierra said. "Why don't you rest?" She gestured to her suite of rooms, which included a sleeping chamber for guests, which Appleton used on his visits. "We can talk more, later."

"Yes, I could do with a little nap." Appleton kissed her on the cheek. "It's funny how I feel so at home with you, even with your new face," he said softly. "Spirit does triumph over flesh, I guess." He retired to her room.

Sierra returned to her scrolls. She looked again at several of the papyri Synesius had provided. Nothing about a cure for any illness of the brain, just scholia by Theon on mathematics.

This cure was like Alcibiades. Neither seemed to exist in this Alexandria.

Where he was now? Dead somewhere in a time that was not his?

The world, of course, still thought that Alcibiades had been murdered in Phrygia, a few years before the death of Socrates. Little did the world know the infinity of alternatives that time travel afforded. . . . Alternities, she thought that some science fiction writer in the future had called them.

The complexities of time travel still taunted her, as always. Mr. Appleton here three times, Alcibiades none – could that have been just another accident of an imprecise time-traveling chair that Alcibiades had attempted to take back here to some time in the past three years? Would he arrive instead a week, a month, a year from now?

She had become accustomed to this world. As Hypatia, she had developed quite a reputation as a logician, a mathematician, a neo-Platonic philosopher. That part had been easy. She had after all already conversed with Socrates and with Plato. She already had had an interest in Pythagoras, Euclid, and the ancient theorists of numbers, inherited from her mother, a professor of mathematics. She already had read many of the relevant ancient treatises and commentaries in her younger days in the distant future. The mathematics were child's play to her, just as the realities of time travel so exquisitely were not.

She even had written several scrolls under Hypatia's name. She wondered: might some of those have been among the treatises she had read years earlier? Maybe that's why she had been attracted to them. Maybe Benjamin Jowett had been right, after all, that it didn't matter who got the credit for your accomplishments.

She returned to Theon's scrolls. Her father of sorts was an optimistic man. He looked for hope. He had no idea he was glimpsing the first grey rays of what would become the deep, Dark Ages. He would have been delighted to discover a cure for any illness. But none were in these writings.

She rubbed her eyes, and wearily picked up another scroll. This one had been badly damaged by the Nitrian fire. It seemed more of a diary than a scholarly commentary, and she had quickly discarded it last night. It apparently had been written a few years prior to Sierra's arrival. It spoke of Theon's boundless love for Hypatia, his fatherly pride in her great work and potential, and–

Sierra slowly unrolled the scroll further. She reread a section that now caught her attention. She traced the words with her index finger, in the ancient style of reading that she had adopted and now often employed without conscious decision:

"A visitor from the East. We had wine by the harbor. We spoke of the brain, and his belief that it was the seat of the soul. We spoke of an illness that could extinguish the soul. How it might be reversed."

There were no further entries like that in the charred scroll. She flicked the black from the tip of her finger.

A thin reed to hang hopes upon, but better than nothing.

* * *

She awoke the next morning and thought about the scroll. Synesius had given it to her. She needed to question him. Her best chance was to try to meet him at his boat in the harbor – possibly it had not yet left for Ptolemais.

She checked on Appleton – he was sleeping soundly. She left him a note, written in English. It said she would be back soon. That is what she intended. But the words looked like lies as soon as they dried on the page.

She walked quickly to the water. She could see in the sky that it was about eight in the morning. She got lucky–

"Hypatia!" Synesius called out to her. He was standing by his boat, chatting with several priests. "You changed your mind and have accepted my invitation!"

"No." Sierra walked up to him, smiling. "I just need to talk to you, for a few minutes."

The bishop frowned. He looked up at the sky, as a man pressed for time in a future millennium might look down at his watch. "Very well. How can I help you?"

Sierra produced the charred scroll. "This contains some text that might be of great value to me. What can you tell me about the person in whose burned house it was found?"

"Very little, I am afraid. He was a wealthy merchant, of the Jewish faith. He valued knowledge, obviously. I do not know why the Nitrians burned his home – I do not know if they killed him. They are fanatics, as I told you. Which is why I worry about you." He shook his head.

"How did you come to acquire this scroll?"

"A younger Jew gave the recovered scrolls to one of my priests."

Someone from the boat called out to Synesius that it was ready for departure.

Sierra squinted at the sun. "Is it too late for me to change my mind, and accept your gracious invitation?"

* * *

Appleton woke, read Sierra's note, and knew how easily "soon" could be "never" when it came to her.

He left Sierra's quarters, in search of his bearings and a midday repast. The Library gleamed in the morning light. This wing of it still looked beautiful, a publisher's dream come true. Green vines, pale yellow flowers, sun-bleached walls, and all of that knowledge within, like the cream inside an Easter egg. He sighed. What could one person do against the fall of night? He knew Sierra was doing all that she could back here. She had told him she put pieces of scrolls in the hands of what passed for funeral directors in this age. "Include them in the tombs, give the departed something to read," she advised them.

She had preserved four copies of the Andros text in this way, that bizarre dialogue of Socrates that had started all of this. She had not listed its true author – her part in setting the plot in motion, her part in making that fiction real. And it had worked. After all, was not Socrates now in the third millennium with Thomas, safe at least for a little while? A miraculous result!

And was not Sierra now here, in the fifth century AD, and not safe at all? A no less miraculous but potentially horrendous result.

But both proof that at least one of her manuscripts had survived more than 1500 years, to be discovered in an excavation in the early 21st century. . . .

How many other texts had she saved from oblivion, by commending them to the safekeeping of shrouds and corpses? It was too late, Appleton knew, for many. History said the legionaries of Julius Caesar had set fire to the Library, whether by accident or intent. Many scrolls had been lost. And a branch of the Library had been destroyed by the evil Bishop Theophilus in 390 AD.

Sierra had told him how that had wounded Theon's heart. She had seen the father of the real Hypatia looking up at his beloved stars many times, mourning his departed books. "How can an astronomer fight the lowness of humanity here on Earth?" Sierra had repeated his lament. But the worst, Appleton and Sierra knew, was yet to come, in the Islamic fires that were now just two centuries away . . . the third and final blow, which would extinguish the Library of Alexandria for all time–

"Not if I can prevent it," Sierra had quietly vowed to Appleton many times.

Appleton long had wondered if that devious inventor Heron had played any role in fomenting those fires. No, not likely – many of his books had died, would die, in those conflagrations, too. The world would have been very different had more of his books and inventions survived. Appleton was a publisher, and it was difficult for him to imagine any publisher or author setting so many of his own books, and so many others, on fire. And yet, had Heron at some point decided, after writing all of those books, that the world would after all be better off without them, or, more to his liking? Appleton reminded himself that Heron of Alexandria was far more than an author and inventor. Heron created not just words and devices but worlds.

Or were the fires perhaps instigated by someone who did not want the world as diagrammed in Heron's texts to happen? Some foe of Heron . . . someone who did not want Heron's worlds, real and imagined, to come into being?

If so, the price was too high. Too many other treatises and plays, works of wonder and beauty, would also be incinerated.

Appleton knew he could likely do little about that. But he was determined not to let Sierra as Hypatia get destroyed by any blaze or lunatic. He would not leave here, this time, without her.

[Ptolemais, 413 AD]

Sierra waited in the shade of the imposing gate on the west side of Ptolemais. Synesius had arranged for the "younger Jew" who had brought the scroll to his priest to meet with her here.

A young man approached and smiled at her.

"You and your smile look familiar," she said, a bit more cleverly than she had intended.

The man's smile increased. "You know my father."

Sierra looked at him, questioningly.

"His was the house that contained Theon's scrolls."

"Oh. I – I did not know he was your father. The Bishop did not mention that. I am sorry. Who was–"

"There are many confidences I do not share with the Bishop. My father's name is Jonah – perhaps that will explain why I look familiar."

Sierra's mouth hung open. "My God – I know Alcibiades saw him in ancient Athens!"

The young man nodded. "You no doubt know some of his earlier life far better than I. My father was Heron's devoted student. He helped Heron and then Thomas with the chairs. Heron grew angry with him. My father could not be sure of Heron's intentions."

Sierra was speechless. "What is your name?" she finally managed. Tears blurred her words. "And Jonah – your father – is he–"

"Yes. He lives. My name is Benjamin."

"Where is he?" Now Sierra cried for joy.

"I do not know." Benjamin looked resigned, awed. "He travels in time."

Sierra nodded. "And your mother? I apologize for asking you so many questions."

"I came to see you today because my father wished me to inform you about whatever you wished to know. My mother died as I was born. She was from an important family in Jerusalem."

"I am sorry," Sierra said again. "How did your father come to live here, in this time and place?"

"He learned of Hypatia's awful fate, some time in his future travels. He thought to warn her – perhaps try to save her, in the same way that Andros in the dialog was proposing to save Socrates. My father learned how the doubles were created. He went to Alexandria in search of Hypatia, and realized she was you–"

"How? We look the same."

"I am not sure," Benjamin replied. "I do not recall my father explaining that to me. Perhaps someone in Alexandria told him. What I do recall is my father said he tried to warn you earlier, or people close to you, not to come to Alexandria. But no one heeded him."

Sierra exhaled, slowly. "Are those your father's words in that burned scroll – about an illness of the brain?"

"No, the words are Theon's. The hand that wrote them is Theon's, is it not?"

"Yes, I am sure Theon's hand wrote those words," Sierra replied. "What I am asking is, did your father speak those words to Theon, which Theon then wrote?"

"I do not believe so," Benjamin said. "I am not sure my father ever met Theon. But he collected anything he could find of Theon's writings, in the present and future. He wants you to have them."

"Why did he not meet me here himself?"

"I do not know," Benjamin replied.

"Why did you not give them to me yourself, after the fire?"

Benjamin looked away. "Forgive me, but I was not sure that I wanted to meet you. You caused pain in my father's life. You may not have wanted that, but . . . I thought it safer that I let the priests give you the scrolls."

"I understand. . . . Thank you," Sierra said, softly, "for coming here today."

"But having met you now," Benjamin said, "I am glad of it."

[Alexandria, 413 AD]

Appleton did not have to wait long. But it was not Sierra who came to him in the Library of Alexandria.

"Mr. Appleton," an approaching voice said quietly, as Appleton sat on one of the Library's sunny patios, eagerly reading a version of Aristotle's Politics he had never seen before. "I barely recognized you in those robes, Mr. Appleton. You look for all the world like a proper Alexandrian scholar."

Appleton looked up and over his shoulder, and nearly jumped out of his robes. "Heron!"

"Please, do not be frightened," Heron said, soothingly. "I mean you no harm."

Appleton rose, and stood his ground. "What brings you here?" he demanded.

"What brings me here?" Heron repeated, a bit less kindly. "This is my city. I have been here, on and off, for centuries. I have been in this particular time, watching you and Hypatia, and tending to other things, for quite some time now."

Appleton's mind reeled. Not surprising Heron was here, of course not, not really surprising at all. "What do you want of us?"

"I want to help Hypatia," Heron replied.

Appleton did not respond.

"There is no need for her to die," Heron continued. "We cannot allow that to happen – she is a great woman."

Appleton still did not speak. Was Heron unaware that Sierra was now Hypatia? "You enjoy saving martyrs. . . ."

"I enjoy betraying death, yes," Heron replied.

"But not when it comes to Alcibiades."

"I saved him, too. Have you forgotten?"

"I also recall well that you almost killed him."

Heron's eyes narrowed. "True. But that was not my plan. And as events turned out, that decidedly would not have been in my best interests."

"But your plan was to lure Sierra Waters back here, in search of a cure for Socrates. Did Theon really write of such a cure? Were you perhaps its source?"

Heron shook his head ruefully. "Would that I was. Our task would be much simpler now. But Theon was the one who told me."

* * *

Sierra returned from Ptolemais the next day. She found Appleton in his room. "See?" she said to him with all the brightness she could muster, "I told you I would be back soon."

"Heron was here yesterday."

"What?!" She spun around and looked out of the doorway, as if Heron was lurking outside. "Are you ok?" She looked back with concern at Appleton.

The Victorian publisher nodded. "It is possible he may really want to help you now."

Sierra rolled her eyes. She spoke to Appleton not about Heron but her meeting with Benjamin. "But now Heron is here? I don't know how much more of this I can bear." She breathed deeply, shakily.

"Come with me, then," Appleton said. He put his hand over hers. "We can leave tomorrow. You'll be safe. Forget Alexandria. Forget Heron."

"Forget about Alcibiades, too? And the cure for Socrates?"

"Listen to me," Appleton said, sternly. "Rome was sacked by the Vandals just three years ago this very month. This world is crumbling around us! You have but to open your eyes to know it!"

"I know about Rome," Sierra said, quietly. "But Alexandria will remain intact a while longer. So will this Library. Hypatia has two more years before she's attacked."

"History is not that precise, not at all, and you should know that by now, too," Appleton muttered darkly and excused himself.

Sierra followed him. "Someone spoke to my father – to Theon – about illnesses of the brain. About a possible cure. Heron was not making that up."

"Heron told me the same," Appleton replied. "Let us then assume that, contrary to his usual habit, he is telling the truth. But that does not mean that there is a cure."

* * *

Sierra promised she would leave Alexandria "soon" with Appleton, without committing to whether that meant weeks or months.

Appleton agreed, because he had no other choice. "Heron did not specify where he was staying, but we should assume he is everywhere. He can interrupt your efforts at any time. He can interrupt your privacy. That alone should make you reconsider–"

But Sierra brushed away his arguments and redoubled her efforts to find the cure. She scrutinized every writing of Theon's she could locate from the time of the charred scroll. Appleton helped. To no avail. If only all of these words on all of these scrolls could be on a computer somewhere, she thought, she could do a proper search. It was a miracle these ancients accomplished anything at all, hamstrung as they were by these words so wedded to paper.

One morning she heard footsteps, when she was reading in her room and Appleton was taking a break by the sea.

"Heron!"

He looked at her through the open doorway and then smiled, sadly.

"When . . . is it, for you?" Sierra asked. "You look older."

"About fifteen years in real time for me, after our encounter in the prison of Socrates," he replied.

"How long has it been for you since you talked with Mr. Appleton, right here?" she asked.

"About two years."

"My God. "

Heron smiled again. "You are supposed to be pagan, take care what you say . . . but, yes, these goals we pursue take time."

Sierra considered Heron's meaning.

"I did not come here empty-handed," Heron said. "I have a plan. May I enter?"

"Yes." It wouldn't hurt to hear it. In fact, the more she knew about Heron – including his lies – the better prepared she would–

"I can get a clone for you," Heron said. "Not really alive. Just like with Socrates. But drugged and walking. To be torn apart at the crucial moment in your stead."

"God almighty!"

"No, you're not convincing as a pagan mathematician at all. Maybe I can get word out to those Nitrians, and that will save you."

"What do you know about the Nitrians?"

"I know the future. And I have met with Synesius," Heron replied.

"How did you–"

"I know just about everything, sooner or later, as you already must know."

"I don't want to leave yet." Not without Alcibiades, who I know will come here in search of the cure, in search of me. But where is he?

"Your words remind me of Socrates," Heron said. "You are reading from the very script he wrote."

Sierra was silent.

"Your search for a cure for the illness of Socrates is a waste of time."

Sierra objected–

"I know about the entry in Theon's diary," Heron said. "I heard the same from his own mouth." Heron put his knuckles to his chin, and shook his head slowly. "The room was crowded. Theon and I were separated. We never had a chance to finish the conversation. He would soon be ill himself. This was shortly before you arrived."

"He wrote the entry before that."

"Yes, of course," Heron said. "But I dared not go back to that time, to question him, and risk dislodging this one thread that we had–"

"That is why I should keep searching now–"

"Don't you think I have searched, and far better than you? Don't you think I know far better than anyone the truth and wisdom that was lost in this burned black hole of Alexandria? Why do you think I told Antisthenes about the possible cure back in the prison that night? Do you think I was really afraid of him? I was hoping, I knew, that my telling Antisthenes would get you and Alcibiades looking for that cure. . . . Ah, what a prime mistake that was! I, of all people, should have known better. . . ." Heron shook his head. "It was an idiot's hope in the first place – if the far future does not have such a cure, how on Earth could they have one back here?"

Sierra looked at him with suspicion and surprise. "Surely you know that the ancients knew some things that the future has yet to rediscover."

"Not as much as you think. Not that." Heron stroked his chin. "And I was responsible for introducing a lot of future knowledge, at least in Alexandria."

"Athens still has a good Library," Sierra said, almost wistfully. "Some of its learned schools endure, though Justinian will close them forever in a hundred years. And Pergamum has some excellent holdings, too. Perhaps they have some of Theon's scrolls."

"Good," Heron said. "Then come with me to Athens. There should be four chairs in that house now. Take yours anywhere in the future you like – I won't get in your way." He had been standing for the entire conversation. Now he sat near Sierra. "Let me take you away from Alexandria."

Sierra stood. "No."

"You would prefer to be ripped to pieces by the Nitrians? Why, when we have an insensate body that can take your place?"

"We can't do that now," Sierra answered. "If my double is killed before 415, that will change history."

"Let me worry about that."

"That's your best response?"

"Maybe Hypatia was murdered in the first place in 413 not 415," Heron said. "But Synesius has been informed about all of this. He will write several accounts of your death and hide them in safe places. They will all say you were murdered by the Nitrians in 415. The date of Hypatia's death will be safeguarded for subsequent history regardless of when they tear your double apart."

Sierra started to reply, then turned her head towards the hall–

"Yes," Heron said. "That would be Appleton the publisher. He wants to leave this place, too. He wants you to leave, as you know. But he will stay here, till his death if he has to, before he abandons you to the Nitrians. If you won't leave here to help yourself, do it to help Mr. Appleton. Please."

Sierra gestured to the hall. "I'll think about it. Now I would like some privacy, if you don't mind." Her nearest weapon, a knife, was unfortunately on the far side of the room, or well beyond her reach. She shuddered, slightly, at the realization of how accustomed she had become to violence. What had Socrates regretfully said about Alcibiades becoming so violent? Now it applied to her–

Heron did not move. "I know noble motives are not the only things that are keeping you here. You want to stay here for Alcibiades."

Did Heron also have the power to read her mind, and know she was thinking about Alcibiades? No, it was only logical, knowing what Heron knew about her and Alcibiades, that Heron would think that. "Do you know what happened to him?"

"You may not like what he has become – it was not my doing."

"Tell me."

"If you agree to leave with me, I will do more than tell you," Heron said. "I will show you."

Sierra shook her head. "Appleton was the last person to see him. I tried to go back to that night in the prison with Socrates, but I couldn't get any closer than nine nights later. There was no trace of anyone by then. You must have restricted the chairs – they don't allow travel now to any time before nine nights after the last evening in the prison of Socrates."

Heron nodded. "We need to keep that night sacrosanct – it is the only way we can make any genuine progress with this time travel. Otherwise, people could keep going back and undoing what we are doing. Socrates would be saved and unsaved and saved and unsaved, forever, in a never-ending loop–"

Sierra realized that Appleton's footsteps had stopped–

Heron caught her expression. "I assure you, I am only trying to help–"

Sierra walked quickly across the room–

But two Roman legionaries were at the door, before the knife was even in her hand.

Heron told them in Latin to take her, but treat her with respect. He addressed Sierra, in the English they had been speaking. "Perhaps this will give you more incentive to come with me. I am reasonably certain that the visitor from the East who spoke to Theon about a cure for the illness of Socrates was Alcibiades."