ABSTRACT
Nothing is known about the characteristics of the earliest known Maghribi zij, Ibn Abi 1-Rijal al-Qayrawam’s Hall al-aqd wa-baydn al-rasd (beginning of the eleventh century), which seems to have been lost. Two centuries later, Abu Abbas Ibn Ishaq al-Tarmrm al-Tunisi, left an unfinished set of tables which survive in a unique manuscript of Hyderabad, discovered in 1978 by D. A. King. All the aforementioned zijes share a certain number of characteristics among which the authors should mention that their mean motion tables are sidereal, and that they contain tables based on the theory of trepidation that enable the user to calculate the amount of precession for a given date and, thus, obtain the tropical longitudes of heavenly bodies.
