Chapter One


The Stranger All of a sudden Galileo felt that this moment had happened before—that he had been standing in the artisans' Friday market outside Venice's Arsenale and had felt someone's gaze on him, and looked up to see a man staring at him, a tall stranger with a beaky narrow face. As before (but what before?) the stranger acknowledged Galileo's gaze with a lift of the chin, then walked toward him through the market, threading through the crowded blankets and tables and stalls spread all over the Campiello del Malvasia. The sense of repetition was strong enough to make Galileo a little dizzy, although a part of his mind was also detached enough to wonder how it might be that you could sense someone's gaze resting on you.

The stranger came up to Galileo, stopped and bowed stiffly, then held out his right hand. Galileo bowed in return, took the offered hand, and squeezed; it was narrow and long, like the man's face.

In guttural Latin, very strangely accented, the stranger croaked, "Are you Domino Signor Galileo Galilei, professor of mathematics at the University of Padua?"

"I am. Who are you?"

The man let go of his hand. "I am a colleague of Johannes Kepler. He and I recently examined one of your very useful military compasses."

"I am glad to hear it," Galileo said, surprised. "I have corresponded with Signor Kepler, as he probably told you, but he did not write to me about this. When and where did you meet him?"

"Last year, in Prague."

Galileo nodded. Kepler's places of residence had shifted through the years in ways Galileo had not tried to keep track of. In fact he had not answered Kepler's last letter, having failed to get through the book ...