ERA OP COPERNICUS, TYCHO BRAIIE, KEPPLER, AND GALILEO. 29 



to the difficulty of obtaining his pension as mathematician to the emperor, through the 

 rapacity of the subordinate officers of government, while the professional astrologers of 

 the court, who flattered the vanity of the great, were magnificently recompensed. Sir 

 Henry Wotton, the English ambassador, finding him in difficulties, invited him to this 

 country ; but Keppler was too strongly attached to his native land to accept the proposal. 

 He thus refers to it in one of his letters : " The fires of civil war are raging in Ger- 

 many they who are opposed to the honour of the empire are getting the upper hand. 

 Shall I then cross the sea, whither Wotton invites me ? I, a German a lover of firm 

 land who dread the confinement of an island who presage its dangers, and must 

 drag along with me my little wife and flock of children ? " At last the fatigue and vex- 

 ation of a fruitless journey to procure payment of his arrears terminated his life at 

 Ratisbon, in the year 1630. The spot where he was buried in the churchyard of 

 St. Peter's cannot now be identified ; but a marble monument, consisting of his bust 

 and the ellipse of Mars, the work of prince Charles of Alberg, has since been erected to 

 his memory. 



The age of Keppler was the era of GALILEO, born at Pisa in 1564, whose discoveries made 

 a profounder impression upon the public mind, and effected more for the system of Co- 

 pernicus, than those of his great compeer, because more open to popular comprehension, 

 though not the fruits of so high an order of intellect. The early part of the seventeenth 

 century was distinguished by the construction of an instrument which rendered objects 

 accessible to human vision in the remoter depths of space, and which speedily added im- 

 portant accessions to the knowledge previously acquired of the visible heavens. A 

 journey to Venice on the part of Galileo in the year 1609, the same year in which Keppler 

 published his commentary on Mars the accidental mention of a fact in a conversation 

 there led to the construction of the telescope, to the accurate survey of the heavens by 

 it, and to the confirmation of those views of the universe which the retired ecclesiastic of 

 Frauenberg had the sagacity to conceive and the boldness to adopt. Having heard that a 

 Dutchman had contrived an instrument that magnified distant objects, the circumstance took 

 possession of the mind of Galileo, and its important application in astronomy was imme- 

 diately perceived. He directed his inventive powers to the construction of such an instru- 

 ment for himself, and ultimately succeeded in perfecting a telescope which, in his own 

 words, could " show things almost a thousand times larger, and above thirty times nearer, 

 to the naked eye." On examining the moon, he at once discovered its analogy with the 

 earth, and detected the fallacy of the Aristotelian physics, which regarded all the celestial 

 bodies as perfectly round, self-luminous, and without any terrestrial tarnish. The lunar 

 surface exhibited plains and mountain ranges, highlands and glens, with the diversity of 

 dark shadows and vivid illumination, which the face of our own globe displays as seen from 

 some towering peak, or from the car of the aeronaut. But a richer harvest awaited him 

 on turning his attention to the planets. Gazing at Jupiter on the night of January 7. 

 1610 a memorable night he saw three small bright stars eastward of the planet, and 

 close to its disk. Subsequent observations revealed a fourth, and ultimately disclosed 

 the fact that Jupiter was before him with a retinue of four satellites, which he named the 

 Medicean stars, from his patrons the Medici. This was a death-blow to that dream of 

 pride which the followers of Aristotle had been indulging for ages ; and one of the chief 

 objections advanced by them to the Copernican doctrine was now demolished. The earth, 

 as their vain philosophy had taught, could no longer be regarded as the most dignified 

 body in the universe, having an attendant moon, and, on that ground, entitled to be the 

 centre ; and, equally, she must resign her right to be at rest, for here was a more dignified 

 body in motion. This revelation of the telescope was as gall and wormwood to the 

 disciples of the ancient creed. They denied, for a time, the existence of the Medicean 



