Museo Galileo
Virtual Museum
Barrois compass
    • Setting:
      Room VI
    • Inventor:
      François Barrois
    • Maker:
      Franz Schwartz
    • Place:
    • Date:
      first half 18th cent.
    • Materials:
    • Dimensions:
      length 255 mm
    • Inventory:
    • Barrois compass (Inv. 656)

This instrument was made by Franz Schwartz, about whom we have no information. It matches the model introduced by François Barrois in 1598 under the name of Compas Barrois. Consists of two intersecting graduated diopters that take the shape of double proportional compasses or a double folding square. On one leg slides a cursor to which is hinged a graduated perpendicular vane with sights. The instrument served to measure the internal and external angles of a building, construct regular polygons, measure heights and distances, and conduct surveying work. Provenance: Medici collections.