astronomy: the astronomical treatise was the Siddhanta which came to be known to the Arabic writers as the Sindhind, it was translated by Ibrahim al-Fazari and opened up a new interest in astronomical studies: some little time afterwards Muhammad b. Musa al-Kharizmi combined the Greek and Indian systems of astronomy, and from this time forth the subject takes a prominent place in Arabic studies. The great Arabic astronomers belong to a later generation, such as Abu Ma'shar of Baghdad, the pupil of al-Kindi, who died in A.H. 272 (= A.D. 885), known to the Latin mediæval writers as "Abumazar," and Muhammad b. Jabir b. Sinan al-Battani (d. 317 A.H. = A.D. 929) who was known as "Albategnius." The Indian work on arithmetic was even more important as by its means the Indian numerals were introduced, to be passed on in due course as "Arabic" numerals, and this decimal system of numbering has made possible an extension of arithmetical processes and indeed of mathematics generally which would have been difficult with any of the older and more cumbersome systems.
Al-Mansur, after founding Baghdad in A.H. 148 (= A.D. 765) summoned a Nestorian physician, George Boktishu', from the school at Junde-Shapur and established him a court physician, and from this time there was a series of Nestorian physicians connected with the court and forming a medical school at Baghdad. George fell ill in Baghdad and was allowed to retire to Junde-Shapur, his place being
