Sentence Examples


  • Idrisi, the best known of the Arabian geographical authors, after travelling far and wide in the first half of the 12th century, settled in Sicily, where he wrote a treatise descrip tive of an armillary sphere which he had constructed for Roger II., the Norman king, and in this work he incorporated all accessible results of contemporary travel.
  • When several rings or circles were combined representing the great circles of the heavens, the instrument became an armillary sphere.
  • Eratosthenes (276-196 B.C.) used most probably a solstitial armilla for measuring the obliquity of the ecliptic. Hipparchus (160-125 B.C.) probably used an armillary sphere of four rings.
  • Chap. i.), and it is of great interest as an example of the armillary sphere passing into the spherical astrolabe.
  • Armillary Sphere.
 

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