1867 The catechetical tradition also recalls that there are “sins that cry to heaven”: the blood of Abel, the sin of the Sodomites, the cry of the people oppressed in Egypt, the cry of the foreigner, the widow, and the orphan, injustice to the wage earner.
By the way, here is the Vatican site on the virtual tour of the Chapel, noted by another site today--synchronicity again...http://vatican.com/tour/sistine_chapel_3D