Search Results: Authors starting with C from Mobilis Books

In the 9th century, the Persian scholar Al-Farghani wrote his Elements of Astronomy on the Celestian Motions (or, Astronomia differentia, also titled Alfragani Elementa Astronomica, because of the lack of authority titles in the pre-Modern period). In part a summary of Ptolomy's Greek Almagest, and in part a scientific tour de force in its own right, the Elements of Astronomy presented a (correct) calculation of the circumference of the earth and the tilt of the Earth's axis. In the 12th century, this Arabic text was translated into Latin, first by John of Seville, then by Gerard of Cremona. The Latin text puts to bed the tired fallacy that particularly Medieval peoples believed the Earth was flat. On this leaf the last line reads: Dicamusque cum puncto sphere terre esset punctus sphere celi necesse fuit ut superficies circuli equinoctii diei divideret superam terre… [And let us say that when the point of the sphere of the earth be the point of the sphere of the sky, it is necessary that the surface… Read More