Restoration of the Sistine Chapel frescoes of the work. Based on this decision, according to Arguimbau's critical reading of the restoration data that has been provided, the chemists of the restoration team decided upon a solvent that would effectively strip the ceiling down to its paint-impregnated plaster. After treatment, only that which was painted "buon fresco" would remain. According to critics, the inherent problem with this approach is that it relied heavily upon an assumption that Michelangelo only painted "buon fresco", that he was always satisfied with the result at the end of the day, and that in four and a half years spent on the
Sistine Chapel ceiling God, he was swallowed by a "mighty fish". He spent three days in its belly and was eventually spewed up on dry land where he went about God's business. Jonah was thus seen as presaging Jesus, who having died by crucifixion, spent part of three days in a tomb and was raised on the third day. So, on the ceiling of the Sistine Chapel, Jonah, with the "great fish" beside him and his eyes turned towards God the Creator, represents a "portent" of the Passion and Resurrection of Christ. The Jonah figure placed right over the altar activated the Passion