Went to Rome to defend the Copernican system, then under official discussion, and as a result was formally forbidden ever to teach it. On the accession of Pope Urban VIII. in 1623, Galileo again visited Rome to pay his respects, and was well received. In 1632 appeared his "Dialogues" on the Ptolemaic and Copernican systems. Summoned to Rome, practically imprisoned, and "rigorously questioned." Was made to recant 22nd of June, 1633. Forbidden evermore to publish anything, or to teach, or receive friends. Retired to Arcetri in broken down health. Death of his favourite daughter, Sister Maria Celeste. Wrote and meditated on the laws of motion. Discovered the moon's libration. In 1637 he became blind. The rigour was then slightly relaxed and many visited him: among them John Milton. Died 8th of January, 1642, aged 78. As a prisoner of the Inquisition his right to make a will or to be buried in consecrated ground was disputed. Many of his manuscripts were destroyed. Galileo, besides being a singularly clear-headed thinker and experimental genius, was also something of a musician, a poet, and an artist. He was full of humour as well as of solid common-sense, and his literary style is brilliant. Of his scientific achievements those now reckoned most weighty, are the discovery of the Laws of Motion, and the laying of the foundations of Mechanics. _Particulars of Jupiter's Satellites, Illustrating their obedience to Kepler's third law._ -------------------------------------------------------------------------- | | | Distance| | | T^2 | | Time of | from | | | ---- Satellite.|Diameter revolution | Jupiter, | T^2 | d^3 | d^3 | miles.| in hours. |in Jovian | | | which is | miles | (T) | radii. | | |practically | | | (d) | | | constant. ----------|-------|------------|----------|---------|---------|----------- No. 1. | 2437 | 42·47 | 6·049 | 1803·7 | 221·44 | 8·149 No. 2. | 2188 | 85·23 | 9·623 | 7264·1 | 891·11 | 8·152 No. 3. | 3575 | 177·72 | 15·350 | 29488· | 3916·8 | 8·153 No. 4. | 3059 | 400·53 | 26·998 |160426· |19679· | 8·152 -------------------------------------------------------------------------- The diameter of Jupiter is 85,823 miles. _Falling Bodies._