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
Mariology of the popes and the veneration of the Blessed Virgin. They made decisions not only in the area of Marian beliefs (Mariology) but also Marian practices and devotions. Popes promulgated Marian veneration and beliefs by authorizing: new Marian feast days, Marian prayers and initiatives, acceptance and support of Marian congregations, indulgences and special privileges, and support for Marian devotions. The formal recognition of Marian apparitions (such as at Lourdes and Fatima) has also been influential. Since Pope Leo XIII, popes have promoted Marian devotion through encyclicals, Apostolic Letters and with two dogmas (Immaculate Conception and Assumption), the promulgation of Marian years (Pius XII,