Horologium Sapientiae was written by the German Dominican Henry Suso between 1328 and 1330. The book belongs to the tradition of Rhineland mystics and German mysticism. It was quickly translated into a range of European languages and (alongside Pseudo Bonaventure's Meditations on the Life of Christ and Ludolph of Saxony's Life of Christ) it was one of the three most popular European devotional texts of the fourteenth and fifteenth centuries. Source: Wikipedia (en)