Sistine Chapel ceiling ceiling include the four so-called Major prophets: Isaiah, Jeremiah, Ezekiel and Daniel. Of the remaining possibilities among the Twelve Minor Prophets, the three represented are Joel, Zechariah and Jonah. Although the prophets Joel and Zechariah are considered "minor" because of the comparatively small number of pages that their prophecy occupies in the Bible, each one produced prophesies of profound significance. They are often quoted, Joel for his "Your sons and your daughters shall prophesy, your elderly shall dream dreams and your youth shall see visions". These words are significant for Michelangelo's decorative scheme, where women take their place among men
Restoration of the Sistine Chapel frescoes watercolour, to integrate the pictorial material. These areas are distinctively textured with vertical brushstrokes, not visible from a distance but easily discernible as restoration work when viewed close up. Certain small areas were left unrestored, in order to maintain a physical record of the previous restorations that had taken place, for example, an area left with overpainting and candle wax, and another area demonstrating the attempt to counteract salination with oil. Once the many layers of candle wax, varnish, and animal glue were removed from the surface of the Sistine Chapel frescoes, they became subject to dangers that could not