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GAL, which he had done, as he says in a letter to Kepler, dated in 1597, many years before. The reputation of Galileo had extended far beyond the university which he adorned. Princes had honoured his lectures with their presence, and Gustavus Adolphus had been his pupil while in Italy. After the expiry of the period of six years of his engagement at Padua, he was re-elected for a similar period with an increased salary of three hundred and twenty florins. In 1604 he observed the remarkable star which excited so much interest, and which he proved to be situated beyond the boundaries of our system. In 1606 he was again appointed to the chair in Padua, with an augmented stipend of five hundred and twenty florins; and so great was his popularity that he was obliged to lecture in the school of medicine, from which, though it contained one thousand persons, an adjournment to the open air was frequently required. The year 1609 was a remarkable one in Galileo's life. Cosmo, grand-duke of Tuscany, invited him to the chair which he had previously occupied in Pisa, and while he was arranging with his patron to have the title of mathematician and philosopher to his highness, and a salary to enable him to carry on his researches without the drudgery of teaching, he was induced to visit a friend in Venice in April or May, 1609. During this visit he learned that Prince Maurice had been presented by a Dutchman with an instrument which made distant objects appear nearer the observer. This Dutchman was John Lippershay, who possessed a telescope so early as the 2nd October, 1608. A letter from James Badorere in Paris confirmed this report, and Galileo having, after his return to Padua, discovered the principle of its action, and constructed a telescope with a spectacle glass at each end of a leaden tube, the one convex and the other concave, he was enabled, by looking through the concave glass, to see objects magnified three times. This little instrument, the size of a modern opera glass, he carried in triumph to Venice. Crowds of the principal citizens flocked to his house to see it. The doge of Venice coveted the magical toy for the senate, and when Galileo had gratified their wishes, they gave him his chair at Padua for life, and raised his salary to one thousand florins.

After Galileo had completed a telescope which magnified thirty times, he lost no time in applying it to the heavens. He discovered the mountains and cavities of the moon; the round discs of the planets as distinct from the appearance of the stars; forty stars in the Pleiades; and the stars of which several nebulæ were composed. On the 7th January, 1610, he discovered three stars near Jupiter, which he found to be satellites like our moon; and on the 13th he detected the fourth satellite—discoveries which were also made by our countryman Harriot on the 17th October of the same year. These discoveries, though opposed by the prejudices of the age, excited great interest in the scientific world, and were fortunately appreciated by the great as well as the wise. The grand-duke of Tuscany observed the new planets along with Galileo at Pisa, and not only gave him a present worth more than a thousand florins, but induced him to resign his chair at Padua, and take up his residence at Florence, with a salary of a thousand florins. In this favoured situation Galileo made many new discoveries. The ring of Saturn was the most important of these. In July, 1610, he described the planet as triple, such as—⬭O⬭ or o⁐o—the central one being larger than the other two. These two small ⬭s are obviously the ansæ or handles of the ring, and the large one the body of the planet. This imperfect observation, however, he is supposed to have greatly improved, for we have lately seen among his papers in the Tribune of Galileo at Florence, a drawing of the complete ring upon which the body of the planet rests, instead of being partially inclosed in it. We think there is satisfactory evidence that Galileo never saw Saturn's ring as in that drawing. If it is not a forgery, and has been actually drawn by himself, it must be a conjectural one, in order to explain the two o s on each side of the body of the planet. His next discovery, made at the end of December, 1610, was the crescent form of Venus, which exhibited all the phases of the moon; and about the same time, if not earlier, he discovered the spots on the sun (independently discovered by Fabricius and Harriot), by the observation of which he found that the sun revolved uniformly upon its axis in about twenty-eight days. M. Arago having tried to prove that Fabricius was the discoverer of the spots in the sun, Baron Plana has sent us an elaborate memoir, read at the Academy of Turin on the 15th March, 1860, placing it beyond a doubt that Galileo had really discovered the spots on the sun about the month of July, 1610, and therefore before Fabricius. Having long contemplated a visit to Rome, he went there with his best telescope early in 1611, and in the Quirinal Gardens, belonging to Cardinal Bandini, he showed the spots of the sun and his other discoveries to the numerous cardinals and prelates, who hastened to do him honour. After his return to Florence he carried on a controversy with Scheiner on the cause of the solar spots, which he also had independently discovered. In 1612 he observed Saturn perfectly round, and without the ansæ—a phenomenon which greatly perplexed him. In the same year he published his "Treatise on Floating Bodies," a work of great merit, which involved him, as all his discoveries did, in harassing disputes with the Aristotelian philosophers. The sceptics of the day took part with Galileo against the monks and the Aristotelians, and a contest arose, in which he wielded against them with terrible effect the weapons of sarcasm and of ridicule. Galileo may be regarded as having begun the combat by a letter to the Abbé Castelli, in which he maintains that the scriptures were not meant to teach philosophy, and that neither the Copernican nor the Ptolemaic system could be reconciled with the Bible. As if in reply to this letter, a Dominican monk of the name of Caccini attacked the philosopher from the pulpit, and roused him to a defence of his opinions, by addressing a powerful letter to the grand-duchess of Tuscany, the mother of his friend and patron. His argument was unanswerable, and its effect irritating to his opponents, because damaging to their cause. To meet it by the force of reasoning was impossible, and the civil power was the only court of appeal when prejudices were to be flattered and truth to be betrayed. An appeal to the inquisition was the obvious policy of the church. Lorini, a dominican monk, had already called its attention to Galileo's letter to Castelli; and Caccini, bribed with the mastership of the convent of Minerva, settled at Rome, in order to collect the evidence against Galileo. There is reason to believe that Galileo was cited to appear at Rome about the end of 1614. At all events he went to that city, and was lodged in the house of the Tuscan ambassador, and soon after was summoned before the inquisition to answer for the passage maintaining the motion of the earth, and the stability of the sun, with having taught it to his pupils, and tried to reconcile it with scripture. These charges were easily substantiated, and on the 25th of February, 1616, he was called upon, at the risk of being imprisoned, to renounce his opinions, and pledge himself neither to teach nor publish them. Having accepted both the renunciation and the pledge in the presence of Cardinal Bellarmine, he was dismissed from the bar of the Holy Office. Thus saved from the fury of his enemies, Galileo did not conduct himself with prudence. The inquisition had resolved to condemn the Copernican system as a dangerous heresy. They placed Copernicus' great work, and Kepler's abridgment of it, in the list of prohibited books; and it is believed that Galileo remained in Rome for the purpose of frustrating this scheme by his influence and conversation. Pope Paul V. nevertheless received him graciously, and assured him that he might consider himself as safe while he occupied the papal chair.

A reward for discovering the longitude at sea having been offered by Philip III., Galileo proposed the method of finding it by observing the eclipses of Jupiter's satellites, and offered to leave his country and his family in order to perfect the method at Seville or at Lisbon. His wishes, however, were not gratified, and there is reason to believe that the grand-duke, unwilling to part with him, threw difficulties in the way.

This disappointment, severe as he considered it, was to some extent compensated by the elevation, in 1623, of his friend the Cardinal Maffei Barberini to the pontificate, under the name of Urban VIII. Several years before this event Galileo had involved himself in disputes about the three comets of 1618, which he erroneously considered to be only meteors in our atmosphere; and, in reply to the attacks which were made upon him, he published, in 1623, his "Il Saggiatore," or the Assayer, which he dedicated to the pope, and which has been greatly admired for the beauty of its style. Urban had been the friend both of Galileo and Prince Cesi, the founder of the Lyncæan academy. The accession to the papal chair of Urban was therefore hailed by the liberal party as the commencement of a more enlightened policy; and, at the instigation of Cesi, Galileo, though an invalid, went to Rome in the spring of 1624 to congratulate his friend on his elevation to the chair of