This chapter applies the previously introduced Winterthur model to the volvelles of the Wittenberg group of Johannes de Sacrobosco’s Sphaera. Six exemplary copies that contain mostly intact versions of each of the volvelles were investigated following the workflow of the Winterthur model: identification, evaluation, cultural analysis, and interpretation. The Wittenberg group contains four volvelle types, the Eclipse, the Horizon, the Zodiac, and the Heliacal Volvelles. To each of the volvelles the model was applied, to examine them in the context of the books. Additionally, they are compared to their appearance in the six exemplary copies, to analyse the volvelles in every possible state (assembled, assembled incorrectly, and unassembled). Additionally, the text parts that relate to the volvelles within the editions were used in the investigation. In this way it was possible to explore the function and use of each of the four volvelles.