This elaborate astrolabe was made by the German craftsman Christoph Schissler. His signature, with the place and date of manufacture, is engraved on the back. Carries a single tympanum for latitudes 45° and 48° (corresponding to the Po Plain and Bavaria). There is a rule. The back displays the alidade, shadow square, degree scale, and hour lines. Brought to Florence from Germany by Prince Mattias de' Medici in the first half of the seventeenth century.