Reception which these Discoveries met with from Kepler 19 Horky; his Work against the Discoveries of Galileo 20 Simon Mayer 21 Discovery of new Satellites 21 First Enigma of Galileo published 23 His Observations on Saturn and Venus 23 1611. His Reception at Rome; he erects his Telescope in the Quirinal Garden 24 (March.) He discovers the Solar Spots 24 1610. Thomas Harriot discovers the Solar Spots (in December) 25 Professor Scheiner; his Letters on the Subject of the Solar Spots 26 These Letters answered by Galileo 26 Faculæ or Luculi discovered on the Sun's Disc, by Galileo 26 His Observations on Saturn 27 The Subject of floating Bridges discussed 28 Galileo "On Floating Bodies" 28 1613. His Letter to the Abbé Castelli 31 Caccini attacks Galileo from the Pulpit 31 Luigi Maraffi apologises to Galileo for this Conduct 31 Galileo, his Letter to the Grand Duchess Christian 31 1615. (26th of February.) Galileo appears before the Inquisition 31 He renounces his Opinions 33 The Copernican System condemned by the Inquisition 34 1616. Interview of Galileo with Pope Paul V. 34 Letter of Querenghi to the Cardinal D'Este 34 Negotiations of Galileo with Spain 35 1618. Three Comets appear 36 1619. Discourse on Comets by Marco Guiducci 36 "The Astronomical and Philosophical Balance" 37 1623. Galileo, his Work "Il Saggiatore" 37 Accession of Cardinal Barberini to the papal Throne 37 1624. Galileo, his Visit to Pope Urban VIII. 38 His Reception 38 1629. Death of Cosmo 39 Pecuniary Difficulties of Galileo 39 1630. Work of Galileo demonstrating the Copernican System 41 1632. "The System of the World of Galileo Galilei" 42 Influence of this Work on the public Mind 43 Galileo summoned to appear before the Inquisition 44 1633.