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result could be rendered compatible with the order ofthe celestial orbits, as determined by the five regularsolids. Sizzi argued seriously with Galileo , that the ap-pearance must be fallacious, since it would invalidate theperfection of the number 7, which applies to the planets,as well as throughout all things natural and divine.Moreover, these satellites are invisible to the naked eye;therefore they can exercise no influence on the earth;therefore they are useless; therefore they do not exist.

Others took a more decided, but not less rational,mode of meeting the difficulty. The principal professorof philosophy at Padua pertinaciously refused to lookthrough the telescope. Another pointedly observed, thatwe are not to suppose that Jupiter has four satellitesgiven him for the purpose of immortalising the Medici(Galileo having called them the Medicean stars). AGerman, named Horky, suggested that the telescope,though accurate for terrestrial objects, was not true forthe sky. He published a treatise discussing the fournew planets (as they were called), what they are?why they are ? and what they are like ? concluding withattributing their alleged existence to Galileo ’s thirstof gold. From misunderstanding a passage in Kepler’swritings, he imagined Kepler to be an opponent ofGalileo , and went to the former with his book, anti-cipating a triumphant reception. He was received in away which effectually set him right. Kepler relatesthe interview in a highly characteristic letter to Galileo .Horky begged hard to be forgiven: Kepler made himpromise to see the satellites when he showed them.

Galileo ’s fame, and that of his telescope, meanwhilewere universally increasing. The grand duke beggedto have the original telescope deposited in the museumat Florence; to which Galileo willingly consented. Anold instrument was shown there not many years ago,said to be the same; but some sceptics have called inquestion its genuineness. The grand duke madeGalileo his own philosopher and principal mathema-tician, with a salary of 1000 florins. The truth of hism 4