As the voyage of Columbus had brought a new world in the western ocean to the notice of Europe, so Galileo’s discoveries with his telescope brought forth a new world in the skies. Galileo wrote out statements of his discoveries, and sent these, with his new telescopes, to the princes and learned men of Italy, France, Flanders, and Germany. At all the courts and universities the telescopes were received with the greatest enthusiasm, and put to instant use in the hope of discovering new stars. But again the followers of Aristotle, those who were unwilling to admit that anything new could be learned about the laws of nature or the universe, arose in wrath. They attacked Galileo and his discoveries. They would not admit that Jupiter had four attendant moons, although these satellites could be seen by any one through the telescope, and a little later, when Galileo stated that the planet Saturn was composed of three stars which touched each other (later found to be one planet with two rings) they rose up to denounce him. But as yet these protests against the discoverer had little effect. Europe was too much interested in what he was showing it to realize how deeply he might affect men’s views of the universe. Fame was now safely his. Men came from all parts of Europe to study under this wonderful professor of Padua. But teaching gave him too little time to carry on his own researches. So he looked about for some other position that would give him greater leisure, and finally stated his wishes to Cosimo II, Duke of Florence. Galileo had named the satellites of Jupiter after the house of Medici, to which this Duke belonged, and Cosimo was much flattered at the compliment. As a result he was soon after made First Mathematician of the University of Pisa, and also Philosopher and Mathematician to the Grand Duke’s Court of Florence. Settled at last at Florence his work as an astronomer steadily went forward. He discovered that the planet Venus had a varying crescent form, that there were small spots circling across the face of the sun, which he called sun-spots, and later that there were mountains on the moon. He also visited Rome, where he was received with the greatest good-will by Pope Paul V and his cardinals, and where he met the leading scientists of the capital.