Irish astronomical tract
Early Modern Irish adaptation based on a Latin translation (Liber de orbe) of a lost astronomical tract written in Arabic by Masha’allah (Māshā’allāh) ibn Athari, a Persian Jewish scholar (fl. early 9th c.). The Irish text appears to be based on a longer, 40-chapter version of the Latin text as opposed to the shorter (27-chapter) and better known version which was first printed in the 16th century and has been attributed to Gerard of Cremona.