would see them, they are so prominent, and you such an experienced astronomer. And I can tell you that on my journey to Rome I have made good progress in determining the period of orbit of all four of these new moons.’
Grienberger and Maelcote raised their eyebrows and exchanged glances. Clavius only smiled. ‘I think here we are in rare agreement with Johannes Kepler, that establishing their periods of rotation will be very difficult.’
‘But…’ Galileo hesitated, then realized he had made a mistake, and dropped the matter with a wave of the hand. There was no point in making announcements in advance of results; indeed, since he was intent on being the first to make every discovery having to do with the new stars, he should not be inciting competitors to further effort. It was already startling enough to see that they had managed to manufacture spyglasses almost as strong as his own.
So he let the talk turn to the phases of Venus. The Jesuits also had seen these, and while he did not press the point that this was strong evidence in support of the Copernican view, he could see in their faces that the implications were already clear to them. And they did not deny the appearances. They believed in the glass. This was a most excellent sign, and as he considered the happy implications of a public acknowledgment that their observations agreed with his, Galileo recovered from his uneasiness at the power of their devices. These were the Pope’s official astronomers, supporting his findings! So he spent the rest of the afternoon reminiscing with Clavius and laughing at his jokes.
Another important meeting for Galileo, though he did not know it, came on the Saturday before Easter, when he paid his respects to Cardinal Maffeo Barberini. They met in one of the outer offices of St Peter’s, near the Vatican’s river gate. Galileo examined the interior gardens of the place with a close eye; he had never been inside the sacred fortress before, and he was interested to observe the horticulture deployed inside. Purity had been emphasized over liveliness, he was not surprised to note: paths were gravelled, borders were lines of clean cobbles, long narrow lawns were trimmed as if by barbers. Massed roses and camellias were all either white or red. It was a little too much.
Barberini proved to be a man of the world, affable, quick, well-dressed in a cardinal’s everyday finery; lithe and handsome, goateed, smooth-skinned, fulsome. His power made him as graceful as a dancer, as confident in his body as a minx or an otter. Galileo handed him the introductory letters from Michaelangelo’s nephew and from Antonio de Medici, and Barberini put them aside after a glance and took Galileo by the hand and led him out into the courtyard, dispensing with all ceremony. ‘Let’s take our ease and talk.’
Galileo was his usual lively self, a happy Pulcinella with a genius for mathematics. In his interviews with nobles he was quick and funny, always chuckling in his baritone rumble, out to please. The Barberini were a powerful family, and he had heard that Maffeo was a virtuoso, with a great interest in intellectual and artistic matters. He hosted many evenings in which poetry and song and philosophical debates were featured entertainments, and he wrote poetry himself that he was said to be vain about. Galileo seemed to be assuming that this was therefore a prelate in the style of Sarpi, broad-minded and liberal. In any case he was perfectly at ease, and showed Barberini his occhialino inside and out.
‘I wish I had been able to bring enough of them with me to leave one with you as a gift, Your Eminence, but I was only allowed a small trunk for baggage.’
Barberini nodded at this awkwardness. ‘I understand,’ he murmured as he looked through the glass. ‘Seeing through yours is enough, for now, and more than enough. Although I do want one, it is true. It’s simply amazing how much you can see.’ He pulled back to look at Galileo. ‘It’s odd-you wouldn’t think that more could be held there for the eye, in distant things, than we already see.’
‘No, it’s true. We must admit that our senses don’t convey everything to us, not even in the sensible world.’
‘Certainly not.’
They looked through it at the distant hills east of Rome, and the cardinal marveled and clapped him on the shoulder in the manner of any other man.
‘You have given us new worlds,’ he said.
‘The seeing of them, anyway,’ Galileo corrected him, to seem properly humble.
‘And how do the Peripatetics take it? And the Jesuits?’
Galileo tipped his head side to side. ‘They are none too pleased, Your Grace.’
Barberini laughed. He had been trained by the Jesuits, but he did not like them, Galileo saw; and so Galileo continued, ‘There are some of them who refuse to look through the glass at all. One of them recently died, and as I said at the time, since he would not look at the stars through my glass, he could now inspect them from up close, on his way past them to Heaven!’
Barberini laughed uproariously. ‘And Clavius, what does he say?’
‘He admits the moons orbiting Jupiter are really there.’
‘The Medici moons, you have called them?’
‘Yes,’ Galileo admitted, realizing for the first time how this could be another awkwardness. ‘I expect to make many more discoveries in the heavens, and hope to honour those who have helped me accordingly.’
The little smile that twitched over the cardinal’s face was not entirely friendly. ‘And you think these Jovian moons show that the Earth goes around the sun in an analogous manner, as Copernicus claimed?’
‘Well, it shows at least that moons go around planets, as our moon goes around the Earth. Better proof of the Copernican view, Your Grace, is how you can see the phases of Venus through the glass.’ Galileo explained how in the Copernican understanding the phases of Venus had combined with its varying distance from Earth to make it give to the naked eye always the same brightness, which had argued against the idea it had phases, when one had no glass to see them; and how its position, always low in the sky in the mornings and evenings, combined with actual sighting of the phases through the glass confirmed the idea that Venus was orbiting the sun inside the Earth’s own orbiting of it. The ideas were complicated to describe in words, and Galileo felt at ease enough to stand and take three citrons from a bowl, then place them and move them about on the table to illustrate the concepts, to Barberini’s evident delight.
‘And the Jesuits deny this!’ the cardinal repeated when Galileo had completed a very convincing demonstration of the system.
‘Well, no. They agree now that the phenomena at least are real.’
‘But then saying that the explanation is not yet so clear. Yes, that makes sense. That sounds like them. And after all, I suppose God could have arranged it any way He wanted.’
‘Of course, Your Grace.’
‘And what does Bellarmino say?’
‘I don’t know, Your Grace.’
The cardinal’s smile was even a little wicked in its foxiness. ‘Perhaps we will find out.’
Then he spoke of Florence, of his love for the city and its nobility, which Galileo happily echoed. And when Barberini asked the usual question about favourite poets, Galileo declared, ‘Oh, I prefer Ariosto to Tasso, as meat over candied fruit,’ which made the cardinal laugh, as being the reverse of the usual characterization of the two; and thus the interview continued well to its conclusion and Galileo’s obsequious withdrawal. And Cardinal Barberini must have enjoyed it, for that very afternoon he wrote to Buonarotti, Michelangelo’s nephew, and to Antonio de Medici, to say he appreciated their recommendations of Florence’s new court philosopher, and would be delighted to help him in any way he could.
A few days later Galileo was invited to a party organized by Giovanni Battista Deti, nephew of the late Pope Clement III, where he met four more cardinals, and listened to a talk given to the group by Giovanni Battista Strozzi. In the discussion afterward Galileo held his tongue, as he told all his correspondents later, feeling that as a newcomer this was the courteous thing to do. Staying silent was no doubt difficult for him, given his natural tendency towards continuous speech, and also given