The Sistine Chapel, erected by Pope Sixtus IV from 1473-1481 and famous for its Renaissance frescoes, is the Papal chapel in the Vatican Palace. Ruskin refers to its shallow barrel vault with frescoes by Michelangelo from 1508-12. Michelangelo, who regarded himself primarily as a sculptor, was unhappy at being required to paint and there is a sculptural quality in the painting. The vault presents a panorama which balances pre-Christian prophets against pagan sybils, the composition bound together by nine histories and four spandrel pictures from the Old Testament, bordered by Christ's ancestors and male nudes. Ruskin discusses the ceiling frescoes in Modern Painters II ( Works, 4.306) and in 'The Lamp of Truth' ( Works, 8.73). In terms of the pictures it contains he rates it with the Camp Santo at Pisa and the Scuolo di San Rocco in Venice as one of the three most precious buildings in Italy ( Works, 11.403).