This volume is primarily a catalogue of books containing the full music of the Mass made between the Bohemian Revolution and the Battle of the White Mountain. Two principal religious factions were active in Bohemia and Moravia during this period. The larger, the Ultraquists, took communion in both bread and wine. The Roman Catholics followed the practice of using bread only. While graduals are important sources for the liturgy practiced by both factions, many of them are also of great interest artistically and historically. Some of the more beautiful books were produced for use by the literary societies, later incorporated as guilds, which were responsible for the music in their churches. The information the books contain about the membership of the guilds gives important information about contemporary social structure. The quality of the art and the evolution in the iconography can be appreciated in the volume's 50 color plates.