Azarquiel School July 4-11, 2010

AL-ZARQALI, Abu Ishaq Ibrahim b. Yaya al-Naqqash al-Tudjibí, known as Walad al-Zarqiyal - whence the Hispanicised form Azarquiel, al-Zarqalluh, al-Zarqal or Ibn Zarqal. Al-Zarqali (sometimes al-Zarqani) and al-Zarqala seem to be classicised Eastern forms not documented in Andalusian sources.
According to Iaq Israeli he was an instrument maker in Toledo. He worked for Sa- cid al-Andalusi (420/1029 - 462/1070) and for king al-Ma'mun (435/1043-467/1075) among others. His patrons lent him the necessary books in which he taught himself astronomy and assumed a leading position in Sacid's group. The Tabaqat (460/1068) mention him as belonging to the  younger Toledan generation (al-adath), but he was active from, at least, 440/1048-49 onwards and his solar observations must have begun between 441/1050 and 446/1055 at the latest.: Abu l-Hasan cAli al-Marrakushi states that he was observing in Toledo in 453/1061. Although no details are extant, these observations are confirmed in al-Zidj al-Kamil fi 'l-Taclim by Ibn al-Ha'im al-Ishbili (fl. 600/1204-05): he attributes to Ibn al-Zarqalluh not only the usual twenty-five years of solar observations but also thirty-seven years of observations of the Moon. According to an anonymous Toledan contemporary, author of a Kitab al-Hay'a discovered by G. Saliba, he appears to have used a large sized instrument. Al-Zuhri  describes a water-clock which marked the date of the lunar month and which was built in Toledo by a certain Abu 'l-Qasim b. cAbd al-Rahman known as al-Zarqal: it is doubtful whether he is referring to the same person.
Ibn al-Zarqalluh left Toledo and went to Cordova either at the beginning of the reign of al-Qadir (473/1081-478/1085) (Ibn al-Abbar), or when Alfonso VI conquered the city in 1085 (postscript by Johannes Hispalensis (?) in a 15th c. MS of the Toledan Tables). In Cordova he was protected by al-Muctamid b. cAbbad (461/1069-484/1091) - to whom he had already dedicated a work in 440/1048-49 - and he continued his observations, with the help of one of his students (Ibn al-Kammad?) until, at least, 480/1087-88. He died in that city on the 8th of Dhu 'l-idjdja 493/15th October 1100 (Ibn al-Abbar).
A classification of Ibn al-Zarqalluh's works should include: