Galileo replied to this attack in a volume entitled _Il Saggiatore_, or _The Assayer_, which, owing to the state of his health, was not published till the autumn of 1623.[24] This work was written in the form of a letter to Virginio Cæsarini, a member of the Lyncæan Academy, and master of the chamber to Urban VIII.[25], who had just ascended the pontifical throne. It has been long celebrated among literary men for the beauty of its language, though it is doubtless one of the least important of Galileo's writings.
The succession of the cardinal Maffeo Barberini to the papal throne, under the name of Urban VIII., was hailed by Galileo and his friends as an event favourable to the promotion of science. Urban had not only been the personal friend of Galileo and of prince Cesi, the founder of the Lyncæan Academy, but had been intimately connected with that able and liberal association; and it was, therefore, deemed prudent to secure his favour and attachment. If Paul III. had, nearly a century before, patronised Copernicus, and accepted of the dedication of his great work, it was not unreasonable to expect that, in more enlightened times, another pontiff might exhibit the same liberality to science.
The plan of securing to Galileo the patronage of Urban VIII. seems to have been devised by prince Cesi. Although Galileo had not been able for some years to travel, excepting in a fitter, yet he was urged by the prince to perform a journey to Rome, for the express purpose of congratulating his friend upon his elevation to the papal chair. This request was made in October, 1623; and, though Galileo's health was not such as to authorise him to undergo so much fatigue, yet he felt the importance of the advice; and, after visiting Cesi at Acqua Sparta, he arrived at Rome in the spring of 1624. The reception which he here experienced far exceeded his most sanguine expectations. During the two months which he spent in the capital he was permitted to have no fewer than six long and gratifying audiences of the pope. The kindness of his holiness was of the most marked description. He not only loaded Galileo with presents[26], and promised him a pension for his son Vincenzo, but he wrote a letter to Ferdinand, who had just succeeded Cosmo as grand duke of Tuscany, recommending Galileo to his particular patronage. "For we find in him," says he, "not only literary distinction, but the love of piety; and he is strong in those qualities by which pontifical good-will is easily obtained. And now, when he has been brought to this city to congratulate us on our elevation, we have very lovingly embraced him; nor can we suffer him to return to the country whither your liberality recalls him, without an ample provision of pontifical love. And that you may know how dear he is to us, we have willed to give him this honourable testimonial of virtue and piety. And we further signify, that every benefit which you shall confer upon him, imitating or even surpassing your father's liberality, will conduce to our gratification."