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 various components of the ceiling are linked to this Christian doctrine. Traditionally, the Old Testament was perceived as a prefiguring of the New Testament. Many incidents and characters of the Old Testament were commonly understood as having a direct symbolic link to some particular aspect of the life of Jesus or to an important element of Christian doctrine or to a sacrament such as Baptism or the Eucharist. Jonah, for example, was readily recognisable by his attribute of the large fish and was commonly seen to symbolise Jesus' death and resurrection. While much of the symbolism of the ceiling dates