One 7 1/2-inch brass sector

1720-1760 in Leiden
Anthonius Hoevenaer

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Overhead view of whole object on graduated grey background. One 7 1/2-inch brass sector by Anthonius Hoevenaer, Leiden
Science Museum Group Collection
© The Board of Trustees of the Science Museum

One 7 1/2-inch brass sector by Anthonius Hoevenaer, Leiden, Holland, 1720-1760

Sectors were the ultimate instrument of proportion. Invented simultaneously by Galileo and Thomas Hood at the end of the 16th century, they enabled many calculations to do with scaling and ratios. While Galileo’s sector was aimed at military gentlemen, it included many lines that were not overtly useful. A preoccupation with Platonic solids is apparent. The lines marked with these figures give the length of side of the five regular solids that can be inscribed in the sphere S, and the length of sides necessary for all the solids to have the same volume.


Object Number:
overall - closed: 4 mm x 190 mm x 45 mm, .248kg
  • furnishing and equipment
  • measuring device - instrument
  • furnishing and equipment
  • measuring device - instrument
  • ruler - measuring device
Sotheby and Compan
Permanent collection

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