“The great quest of medieval science was for a perfect copy of Ptolemy’s Almagest, written in Egypt in 147 AD. It was known to have thirteen sections, with the most accurate analysis of star and planetary paths ever achieved, alongside a catalogue of 1,022 starts listed on a scale of magnitude from 1 to 6. It was a key that threatened to unlock the secrets of the heavens.”
Excerpted from: Rogerson, Barnaby. Rogerson’s Book of Numbers: The Culture of Numbers–from 1,001 Nights to the Seven Wonders of the World. New York: Picador, 2013.