Astronomy.— The great foundation stone of modern astronomy was laid by Copernicus. He was a Pole, who studied in Italy for some 10 years and then spent the rest of his life quietly as the canon of the Cathedral of Frauenberg, where, after making careful observations, he worked out his theory of the universe. He had already begun to think about it while he was in Italy and the Copernican theory was publicly taught in Rome long before Copernicus' great book was published This work was dedicated with permission to Pope Paul III. Copernicus continued to be until the end of his life a staunch supporter of his friend and patron, Bishop Maurice Ferber of Ermland, who kept his see loyal to Rome at a time when the secularization of the Teutonic Order and the falling away of many bishops all round him made his position as a faithful son of the Churel noteworthy in the history of that time and place. When Galileo insisted on stating Copernicanism as an absolute scientific doctrine instead of a theory, Copernicus' book was placed on the index (though not unconditionally, for its author is spoken of as as noble as trologer* when the word astrologer meant as tronomer) but only until certain passages in which theories were stated as facts should be modified so as to make their theoretic signifi cance clear.
Before Copernicus a number of distinguished clergymen had attracted attention by their astronomical teaching. Bishop Vergilius, the Irish missionary astronomer of the 8th century, taught that the earth was round and freed him self from the charge that his teaching was con trary to scriptures. Albertus Magnus insisted that there were antipodes, taught the rotundity of the earth and other supposedly modern astronomical doctrines yet was always in high favor, was made a bishop, and after his death canonized as a saint. In the 15th century Cardinal Nicholas of Cusa taught that °the earth is a star as the other stars in the heaven.* and that it had a movement of its own and could not be the centre of the universe. Though deeply interested in science and teaching many new and startling doctrines for his time he was made Bishop of Brixen, then Papal Legate to Germany for the reform of abuses, and finally a Cardinal, being a close friend of sev eral popes. The first epoch-making astronomer of modern times was Regiomontanus, who established a regular observatory at Nurem berg. He was summoned to Rome to direct the calculations for the correction of the calendar. His invitation to Rome for this pur pose was within 10 years of the time when Pope Calixtus III is said to have issued a Bull against Halley's comet. The supposed Bull has never been found. Toscanelli who influenced Columbus so deeply was an intimate friend of Cardinal Nicholas of Cusa as well as of Regiomontanus and also of the famous Antoninus, Archbishop of Florence. Antoninus
taught very emphatically that comets are celes tial bodies like others in the heavens and had no effect on the physical or moral conditions of the world. Regiomontanus who was also a priest was a dose friend of Toscanelli's. The relations between the ecclesiastical authorities and Toscanelli are illustrated by the gnomon which he arranged in the dome of the cathedral at Florence, by the shadow of which it is said that he could determine midday within half a second. Cardinal Ximenes of Spain improved this accuracy of determining noon by similar means so that the cordial ecclesiastical rela tions with science were not confined to Italy.
Toward the end of the 16th century Pope Gregory XIII, intent on the correction of the calendar, had an observatory erected in the Vatican Gardens for astronomical purposes, and here the meetings of the mathematicians and astronomers for the reform of the calen dar were held. After this there was always a Roman Observatory directly under the patron age of the popes, either in the Vatican or the Roman College in charge of the Jesuits. When the Jesuits were suppressed or expelled by the Italian government the Vatican observatory was resumed as at the present time when it is under the charge of Father Hagan, S.J., who was for a time at the observatory at George town University, D. C. The Jesuit astronom ers, though the order was directly under the control of the Pope, taking a special vow of obedience to him, have done some excellent original work in astronomy. Nearly every important Jesuit College in the 17th and 18th centuries had an observatory, and secular students of astronomy made it a point to keep in touch with them. Professor Foster in The Quarterly Journal of the German Astronomi cal Society (1890, page 60) said, °Among the members of the Society of Jesus in the past and in the present we find so many excellent astronomers and in general so many investi gators of purest scientific devotion that it is of important interest to their colleagues in science to notice them' The great names among them in astronomy are Father Clavius, to whom the Gregorian reform of the calendar is due; Father Scheiner, the authority on the sun and particularly on sun spots; Father Grimaldi, an authority on the moon, and Father Riccioli, who introduced the lunar nomenclature in use to-day. Three Jesuits, Fontaney, Noel and Richaud, are mentioned by Humboldt in his (Kosmos) as early observers of double stars. In the modern time Father Secchi has been of deep influence on present day astronomy, and Fathers Perry, De Vico and Sidgreaves have done excellent work on government astronomi cal commissions.