It was easy to imagine a lens grinder in the course of his work holding up two lenses, one in front of the other, to see what would happen. He was surprised he hadn’t done it himself. Although, as he had just discovered, it didn’t do much. He could not immediately say why. But he could investigate the phenomenon in his usual manner. At the very least he could look through different kinds of lenses in various combinations, and simply see what he saw.

There was no wind this Friday afternoon, and the ferry’s crew rowed slowly along the Canale della Giudecca and onto the open lagoon, headed for the fondamente at Porta Maghere. The captain’s ritual cursing of the oarsmen cut through the cries of the trailing seagulls, sounding like lines from Ruzante. You girls, you rag dolls, my mother rows better than you do—

“Mine definitely does,” Galileo pitched in absently, as he always did. The old bitch still had arms like a stevedore. She had been beating the shit out of Marina until he had intervened, that time the two had fought; and Galileo knew full well that Marina was no slouch when it came to landing a punch. Holding them apart, everyone screaming …

From his spot in the ferry’s bow he faced the setting sun. There had been many years when he would have spent the night in town, usually at Sagredo’s pink palazzo—“The Ark”—with its menagerie of wild creatures and its riotous parties. But now Sagredo was in Aleppo on a diplomatic assignment, and Paolo Sarpi lived in a stone monk’s cell, despite his exalted office, and all the rest of Galileo’s partners in mischief had also moved away or changed their night habits. No, those years were gone. They had been good years, even though he had been broke—as he still was. Work all day in Padua, party all night in Venice. Thus his rides home had usually been on a dawn barge, standing in the bow buzzing with the afterglow of wine and sex, laughter and sleeplessness. On those mornings the sun would pop over the Lido behind them and pour over his shoulders, illuminating the sky and the mirror surface of the lagoon, a space as simple and clear as a good proof: everything washed clean, etched on the eye, glowing with the promise of a day that could bring anything.

Whereas coming home on the day’s last barge, as now, was always a return to the home fire of his life’s endlessly tangled problems. The more the western sky blazed in his face, the more likely his mood was to plummet. His temperament was volatile, shifting rapidly among the humors, and every histrionic sunset threatened to make it crash like a pelican diving into the lagoon.

On this evening, however, the air was clear, and Venus hung high in a lapis lazuli dusk, gleaming like some kind of emblem. And he was still thinking about the stranger and his strange news. Could it be true? And if so, why had no one noticed before?

On the long dock up the estuary he debarked, and walked over to the line of carts starting out on their night journeys. He hopped on the back of one of the regulars that went to Padua, greeting the driver and lying on his back to watch the stars bounce overhead. By the time the cart rolled past Via Vignali, near the center of Padua, it was the fourth hour of the night, and the stars were obscured by cloud.

With a sigh he opened the gate that led into his garden, a large space inside the L formed by the big old house. Vegetables, vine trellises, fruit trees: he took a deep breath to absorb the smells of the part of the house he liked best, then steeled himself and slipped into the pandemonium that always existed inside. La Piera had not yet entered his life, and no one before her could ever keep order.

“Maestro!” one of the littlest artisans shrieked as Galileo entered the big kitchen, “Mazzoleni beat me!”

Galileo smacked him on the head as if driving a tomato stake into the ground. “You deserved it, I’m sure.”

“Not at all, maestro!” The undeterred boy got back to his feet and launched into his complaint, but did not get far before a gaggle of Galileo’s students surrounded him, begging for help with a problem they were to be tested on next day in the fortifications course at the university.

“We don’t understand,” they wailed contrapuntally, though it appeared to be a simple problem.

“Unequal weights weigh equally when suspended from unequal distances having inversely the same ratio as the weights,” Galileo intoned—something he had tried to teach them just the previous week. But before he could sit down and decipher their teacher Mazzoni’s odd notation, Virginia threw herself into his arms to recount in officious detail how her younger sister Livia had misbehaved that day. “Give me half an hour,” he told the students, picking up Virginia and carrying her to the long table. “I’m starving for supper, and Virginia is starving for me.”

But they were more afraid of Mazzoni than they were of him, and he ended up reviewing the relevant equations for them, and insisting they work out the solution for themselves, while eating the leftovers from their dinner, all the while bouncing Virginia on his knee. She was light as a bird. He had banned Marina from the house five years before, a relief in many ways, but now it was up to him and the servants to raise the girls and find them a way in the world. Inquiries at the nearby convents, asking for prenovitiate admissions, had not been well received. So there were some years yet to go. Two more mouths, lost among all the rest. Among thirty-two mouths, to be exact. It was like a hostel in Boccaccio, three stories of rooms all overoccupied, and every person there dependent on Galileo and his salary of 520 florins a year. Of course the nineteen students boarding in-house paid a tuition plus room and board, but they were so ravenous he almost always fed them at a loss. Worse, they cost time. He had priced his military compasses at five scudi each, with twenty more charged for a two-month instructional session, but considering the time it took from him, it had become clear that he made each sale at a loss. Really, the compasses had not turned out as he had hoped.

One of the houseboys brought him a small stack of letters a courier had brought, which he read as he ate and tutored and played with Virginia. First up was another letter from his sponge of a brother, begging for money to help support him and his large family in Munich, where he was trying to make it as a musician. Their father’s failure in that same endeavor, and the old dragon’s constant excoriation of him for it, had somehow failed to teach his brother Michelangelo the obvious lesson that it couldn’t be done, even if you did have a musical genius, which his brother did not. He dropped the letter on the floor without finishing it.

The next one was worse: from his sister’s unspeakable husband Galetti, demanding again the remainder of her dowry, which in fact was Michelangelo’s share, but Galetti had seen that the only chance for payment was from Galileo. If Galileo did not pay it, Galetti promised to sue Galileo yet again. He hoped Galileo would remember the last time, when Galileo had been forced to stay away from Florence for a year to avoid arrest.

That letter too Galileo dropped on the floor. He focused on a half-eaten chicken, then looked in the pot of soup hanging over the fire, fishing around for the hunk of smoked pork that ballasted it. His poor father had been driven to an early grave by letters just like these, and by his Xantippe ferreting them out and reading them aloud fortissimo. Five children, and nothing left even to his eldest son, except a lute. A very good lute, it was true, one that Galileo treasured and often played, but it was no help when it came to supporting all his younger siblings. And mathematics was like music in this, alas: it would never make enough money. Five hundred twenty florins a year was all he was paid for teaching the most practical science at the university, while Cremonini was paid a thousand for elaborating Aristotle’s every throat-clearing.