Thus it was determined that each of the three must act as if the other two had already failed. Each must carry out the mission with as much care as if everything depended on him or her alone, for it very well might be true.

But they hoped that all three time machines would work, that all three travelers would reach their separate destinations. Diko would arrive in Haiti in 1488, Kemal in 1492; Hunahpu would reach Chiapas in 1475. "There is a certain sloppiness in nature," Manjam had told them. "True precision is never achieved, is never even possible, and so everything that happens depends on a certain amount of probability, has a little leeway, a bit of room to compensate for lapses and mistakes. Genetic molecules are filled with redundancy and can cope with a certain amount of loss or damage or extra insertions. Electrons moving through their quantum shells have a certain range of unpredictability about their exact location, for all that matters is that they remain at the same distance from the nucleus. Planets wobble in their orbits and yet persist for billions of years without falling into their motherstars. So there should be room for microseconds or milliseconds or centiseconds or even deciseconds of difference between the beginnings of the three fields. But we have no way of experimenting to see just what the tolerances are. We may have far exceeded them. We may have missed by a fraction of a nanosecond. We may have been so far from success as to have made this whole venture wasted time. Who can know these things?"

Why is it, thought Tagiri, that even though I know that within a few minutes I and my dear husband and my precious son Acho will almost certainly wink out of existence, it is Diko that I am grieving for? She is the one who will live. She is the one with the future. Yet the animal part of me, the part that feels emotion, does not comprehend my own death. It is not death, when the whole world dies with you. No, the animal part of me only knows that my child is leaving me, and that is what I grieve for.

She watched as Hunahpu helped Diko up the ladder, then walked to his own hemisphere and climbed.

And now it was Tagiri's own turn. She kissed and embraced Hassan and Acho, and then climbed her own ladder, up to the locked cage. She pressed the button to open it as Manjam and Hassan also pressed their widely separated buttons, as Diko and Hunahpu and Kemal pressed the buttons on their field generators. The lock clicked and she pushed open the door of the cage and stepped inside.

"I'm in," she said. "Release your buttons, travelers."

"Get in position," called Sd.

Tagiri was now above the hemispheres and could see as Kemal and Diko and Hunahpu curled up on top of their equipment and supplies, making sure that no part of their bodies was under the field generator or extending beyond the boundaries of the sphere that the field generator would create.

"Are you ready?" called Sa.

"Yes," answered Kemal at once.

"Ready," said Hunahpu.

"I'm ready," said Diko.

"Can you see them?" called Sa, now talking to Tagiri and to the other three watchers who were in position to see. All of them confirmed that the travelers seemed to be in a good position.

"When you are ready, Tagiri," said Sd.

Tagiri hesitated only a moment. I am killing everyone so that everyone can live, she reminded herself. They chose this, as much as anyone with imperfect understanding can ever choose. From birth we all were fated to die, and so it is good that at least we can be sure our deaths today might bring about a good end, might make the world a better place. This litany of justification passed quickly, and again she was left with the pain that had gnawed at her for the weeks, the years of this project.

For a fleeting moment she wished that she had never joined Pastwatch, rather than to face this moment, to have it be her hand that pulled the switch.

Who else's hand? she asked herself. Who else should bear this responsibility, if I cannot bear it? All the slaves waited for her to bring them freedom. All the unborn children of countless generations of humanity waited for her to save them from the withering death of the world. Diko waited for her to send her out into the great work of her life. She grasped the handle of the switch. "I love you," she said. "I love you all."

She pulled it down.

Did the Lord say that Cristoforo would be the first to see the new land? If he did, then the prophecy must be fulfilled. But if he did not, then Cristoforo could allow Rodrigo de Triana to claim credit for seeing land first. Why couldn't Cristoforo remember the exact words the Lord said? The most important moment in his life until now, and the wording escaped him completely.

No mistaking it, though. In the moonlight seeping through the clouds everyone could see the land; sharp-eyed Rodrigo de Triana had first seen it an hour ago, at two in the morning, when it was nothing but a different-colored shadow on the western horizon. The other sailors were gathered around him now, offering their congratulations and cheerfully reminding him of his debts, both real and imaginary. As well they should, for the first to see land had been promised a reward of ten thousand maravedis a year for life. It was enough to keep a fine household with servants; it would make de Triana a gentleman.

But what was it, then, that Cristoforo had seen earlier tonight, at ten o'clock? Land must have been close then, too, scarcely four hours before de Triana saw it. Cristoforo had seen a light, moving up and down, as if signaling him, as if beckoning him onward. God had shown land to him, and if he was to fulfill the words of the Lord, he must lay the claim.

"I'm sorry, Rodrigo," called Cristoforo from his place near the helm. "But the land you see now is surely the same land I saw at ten o'clock."

A hush fell over the company.

"Don Pedro Gutierrez came to my side when I called him," said Cristoforo. "Don Pedro, what did we both see?"

"A light," said Don Pedro. "In the west, where the land now lies." He was the King's majordomo -- or, to put it bluntly, the King's spy. Everyone knew he was no particular friend to Colўn. Yet to the common sailors, all gentlemen were conspirators against them, as it certainly seemed to them now.

"I was the one cried 'land' before anyone," said de Triana. "You gave no sign of it, Don Cristobal."

"I admit that I doubted it," said Cristoforo. "The sea was rough, and I doubted that land could be so near. I convinced myself that it could not be land, and so I said nothing because I didn't want to raise false hopes. But Don Pedro is my witness that I did see it, and what we all see now bears out the truth of it."

De Triana was outraged at what seemed to him to be plain theft. "All those hours I strained my eyes looking west. A light in the sky isn't land. No one saw land before I did, no one!"

Sdnchez, the royal inspector -- the King's official representative and bookkeeper on the voyage -- immediately spoke up, his voice whipping sharply across the deck. "Enough of this. On the King's voyage, does anyone dare to question the word of the King's admiral?"

It was a daring thing for him to say, for only if Cristoforo reached Cipangu and returned to Spain would the title Admiral of the Ocean-Sea belong to him. And Cristoforo well knew that last night, when Don Pedro had affirmed that he saw the same light, Sdnchez had insisted that there was no light, that there was nothing in the west. If anyone was going to cast doubt on Cristoforo's claim to first sighting, it would be Sanchez. Yet he had supported, if not Cristoforo's testimony, then his authority.

That would do well enough.

"Rodrigo, your eyes are indeed sharp, " said Cristoforo. "If someone on shore had not been casting a light -- a torch, or a bonfire -- I would have seen nothing. But God led my eyes to the shore by that light, and you merely confirmed what God had already shown me."