Sistine Chapel ceiling of the Sistine Chapel. At the outset, the plaster, "intonaco", began to grow mold because it was too wet. Michelangelo had to remove it and start again. He then tried a new formula created by one of his assistants, Jacopo l'Indaco, which resisted mold and entered the Italian building tradition. Because he was painting "fresco", the plaster was laid in a new section every day, called a "giornata". At the beginning of each session, the edges would be scraped away and a new area laid down. The edges between "giornate" remain slightly visible; thus, they give a good idea of
Sistine Chapel ceiling Julius who began the rebuilding of St. Peter's Basilica in 1506, as the most potent symbol of the source of papal power. In the same year 1506, Pope Julius conceived a program to paint the ceiling of the Sistine Chapel. The walls of the chapel had been decorated twenty years earlier. The lowest of three levels is painted to resemble draped hangings and was (and sometimes still is) hung on special occasions with the set of tapestries designed by Raphael. The middle level contains a complex scheme of frescoes illustrating the "Life of Christ" on the right side and the