Copernican view of the universe, the spots on the sun. By attentively observing their motions on the sun's disk he afterwards discovered the sun's motion on its own axis, a fatal blow to the Ptolemaic system. Although to science it may be quite indifferent whether Galileo, or Fabricius, or the Jesuit father Scheiner first espied the spots on the sun (for they all lay claim to the discovery), for us it has its importance, because the bitter contention between Galileo and Scheiner on the subject materially contributed to set the stone rolling which, in its fall, was no less disastrous to the moral greatness of Galileo than to the erudition of Rome.
In consideration of the intense interest excited by Galileo's "epoch-making" discoveries, the Roman curia, which still held it to be one of its most important duties to guard mankind as much as possible from precocious knowledge, was of course eager to learn more about them, and above all, of the conclusions which the discoverer drew from them. It must also have appeared of great importance to Galileo to acquaint the Roman savans and dignitaries of the Church with his scientific achievements, for the authority and influence then exercised by them over the free progress of science made their opinions of the utmost moment to him. They must, if possible, be first made to see the premises with their own eyes, that they might afterwards be able to comprehend and assent to the conclusions. Galileo clearly saw this, as appears from a letter of 15th January, 1611, to Vinta[1] (who was then with the court at Pisa), in which he urgently begs permission for a visit to the papal residence. The request was not only immediately granted, but the court placed a litter at his disposal, undertook to defray all his expenses, and directed the Tuscan ambassador at Rome to prepare quarters for him at the embassy and to entertain him during the whole of his stay.[2] Meanwhile, however, Galileo was at-
