" An experiment with a h2o-crammed glass sphere was executed and al-Farisi showed the additional refractions due to the glass could be disregarded in his design.[74][c] As he pointed out in his Kitab Tanqih al-Manazir (The Revision with the Optics), al-Farisi employed a sizable clear vessel of glass in The form of a sphere, which was crammed with d