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Stand with tackle and polyspaston
    • Setting:
      Room VII
    • Inventor:
      Willem Jacob 's Gravesande
    • Maker:
      unknown
    • Date:
      second half 18th cent.
    • Materials:
      ivory, wood, brass
    • Dimensions:
      550x550x1200 mm
    • Inventory:
      539, 1401
    • Stand with tackle and polyspaston (Inv. 539, 1401)

This apparatus (incomplete) is known as 's Gravesande column, named after its inventor. The "column" is an all-purpose stand suitable for a wide range of mechanical and hydrostatic experiments.

The square base supports a vertical column holding four crossbars, of which four rotate and one slides. A tackle and a polyspaston are suspended from two different crossbars. The tackle consists of two ebony blocks each carrying five ivory sheaves and interconnected by a single cord. With this combination, an effort applied to the free end of the cord can lift a load ten times greater. The polyspaston comprises two horizontal rods each carrying three pulleys connected by a cord. This combination makes it possible to lift a weight six times as great as the effort applied. Provenance: Lorraine collections.