Music of Vatican City a result, reformers like Palestrina revised the rules behind Gregorian chanting, which were printed by the Medici Press in Rome; these reforms continued to be followed to the present day. A traditional musical instrument was the pipe organ. After the end of the Papal States the Popes' ability to sponsor composers and musicians waned. However it did not end entirely nor did interest in the subject. Pope Pius X and Pope Pius XII both wrote on the subject. In modern times John Harbison and Gilbert Levine have composed or conducted for the Vatican. Although not of the Vatican a Christmas
Prophecy of the Popes called "Purported prophecies", that the high level of accuracy of the alleged prophecies up until the date they were published, compared with their high level of inaccuracy after that date, is evidence that they were created around the time of publication. The prophecies and explanations given in Wion correspond very closely to a 1557 history of the popes by Onofrio Panvinio (including replication of errors made by Panvinio), which may indicate that the prophecies were written based on that source. One theory to explain the creation of the prophecies, put forward by 17th-century French priest and encyclopaedist Louis Moréri, among