to this.' He then returned to Ziyád and said, 'I will do what you ordered.'"[643] The Baṣra school of grammarians which Abu ’l-Aswad is said to have founded is older than the rival school of Kúfa and surpassed it in fame. Its most prominent representatives were Abú ‘Amr b. al-‘Alá († 770 A.D.), a diligent and profound student of the Koran, who on one occasion burned all his collections of old poetry, &c., and abandoned himself to devotion; Khalíl b. Aḥmad, inventor of the Arabic system of metres and author of the first Arabic lexicon (the _Kitábu ’l-‘Ayn_), which, however, he did not live to complete; the Persian Síbawayhi, whose Grammar, entitled 'The Book of Síbawayhi,' is universally celebrated; the great Humanists al-Aṣma‘í and Abú ‘Ubayda who flourished under Hárún al-Rashid; al-Mubarrad, about a century later, whose best-known work, the _Kámil_, has been edited by Professor William Wright; his contemporary al-Sukkarí, a renowned collector and critic of old Arabian poetry; and Ibn Durayd († 934 A.D.), a distinguished philologist, genealogist, and poet, who received a pension from the Caliph Muqtadir in recognition of his services on behalf of science, and whose principal works, in addition to the famous ode known as the _Maqṣúra_, are a voluminous lexicon (_al-Jamhara fi ’l-Lugha_) and a treatise on the genealogies of the Arab tribes (_Kitábu ’l-Ishtiqáq_). [Sidenote: The philogists of Kúfa.] Against these names the school of Kúfa can set al-Kisá’í, a Persian savant who was entrusted by Hárún al-Rashíd with the education of his sons Amín and Ma’mún; al-Farrá († 822 A.D.), a pupil and compatriot of al-Kisá’í; al-Mufaḍḍal al-Ḑabbí, a favourite of the Caliph Mahdí, for whom he compiled an excellent anthology of Pre-islamic poems (_al-Mufaḍḍaliyyát_), which has already been noticed[644]; Ibnu ’l-Sikkít, whose outspoken partiality for the House of ‘Alí b. Abí Ṭálib caused him to be brutally trampled to death by the Turkish guards of the tyrant Mutawakkil (858 A.D.); and Tha‘lab, head of the Kúfa school in his time († 904 A.D.), of whose rivalry with al-Mubarrad many stories are told. A contemporary, Abú Bakr b. Abi ’l-Azhar, said in one of his poems:-- "Turn to Mubarrad or to Tha‘lab, thou That seek'st with learning to improve thy mind! Be not a fool, like mangy camel shunned: All human knowledge thou with them wilt find. The science of the whole world, East and West, In these two single doctors is combined."[645] Reference has been made in a former chapter to some of the earliest Humanists, _e.g._, Ḥammád al-Ráwiya († 776 A.D.) and his slightly younger contemporary, Khalaf al-Aḥmar, to their inestimable labours in rescuing the old poetry from oblivion, and to the unscrupulous methods which they sometimes employed.[646] Among their successors, who flourished in the Golden Age of Islam, under the first ‘Abbásids, the place of honour belongs to Abú ‘Ubayda († about 825 A.D.) and al-Asma‘í († about 830 A.D.).