Harun was not, indeed, the first prince who made arrangements for translations from the Greek and the Syriac. In this he had been preceded, as already mentioned, by the Omaiyide prince, Khalid, the alchemist. But during the reign of Harun the business of translation was carried on to a much greater extent than it was under his predecessors, the Khalifs Mansur and Mahdi, during whose time translations were undertaken from Greek into Syriac, from Indian (Sanscrit) into Persian, but not yet into Arabic. The translators were mostly Christians and Jews. Theophilos of Edessa, the Maronite translator of Homer and of other Greek classics into Syriac, was an astronomer and an historian. Both he and the physician Georgios, son of Bakhtyeshun, from the university of Jondshapur, were Christians. Nubakht, the astronomer of the Khalif Mansur, was a Magian (Zoroastrian), Yahya bin Maseweih, Harun's physician, translated medical works. Hajaj bin Yusuf bin Matta dedicated his first edition of the elements of Euclid to Harun, and the second to Mamun. As the family of the Barmekides played an important part, not only in politics, but also in literature, until its chief members were annihilated by Harun's orders, a brief notice of them may here be given. Khalid bin Barmek was the son of a priest at the fire temple of Nevbehar in Balkh, and became in course of time vizier of the first Abbaside Khalif, and was retained in that office by the second Khalif, Al-Mansur, and by the third, Al-Mahdi. He died A.D. 780. Yahya, the son of Khalid, not only himself became the vizier of Harun, but also his two sons, Fadhl and Jaafar. Yahya was very liberal, and gave away sometimes considerable sums of money for very small services, or, indeed, for no service at all. After his son Jaafar had been executed, Yahya was thrown into prison, along with his other son, Fadhl, at Old Rakka, where he died in A.D. 805, at the age of seventy or seventy-four.