Abulfeda (Annal. Moslem. p. 210, 211, vers. Reiske) describes this operation according to Ibn Challecan, and the best historians. This degree most accurately contains 200,000 royal or Hashemite cubits which Arabia had derived from the sacred and legal practice both of Palestine and Egypt. This ancient cubit is repeated 400 times in each basis of the great pyramid, and seems to indicate the primitive and universal measures of the East. See the Metrologie of the laborions. M. Paucton, p. 101 - 195.