Museo Galileo
Virtual Museum
Diptych dial
    • Setting:
      Room II
    • Maker:
    • Place:
    • Date:
    • Materials:
      ebony, ivory
    • Dimensions:
      70x56 mm
    • Inventory:
    • Diptych dial (Inv. 2489)

Dial consisting of an oval ebony box with a decorated and painted lid. Inside the lid are marked latitudes 43°, 45°, and 48°, with three corresponding holes. These latitude values suggest the instrument came from France. The base is fitted with a compass for orientating the dial and hour lines marked on three concentric bands. A string is stretched between the lid and the base. When the box is opened, the string, inserted in the hole corresponding to the selected latitude, casts its shadow on the hour lines. The instrument was already documented in the reign of Grand Duke Cosimo I de' Medici. Probable provenance: Medici collections.