[85] The history of Mesopotamian rivers is exceedingly complicated owing to the frequency with which they change their beds. Mr. Le Strange (_Lands of the Eastern Caliphate_, p. 70 _et seq._) believes that the Nahr Hindîyeh, which is probably identical with the ’Alḳâmî of Ḳudâmah and Mas’ûdî, was considered in the tenth century to be the main stream of the Euphrates, though even at that time it was not so broad as the Ḥilleh branch. Writing in 1905 Mr. Le Strange speaks of the Ḥilleh branch as being undoubtedly the main stream in modern times, but in 1909 nearly all the water, as I shall describe, flowed down the Kûfah branch (the Hindîyeh canal) and the Ḥilleh branch lay dry all the winter. This, however, will, it is to be hoped, be rectified by the new irrigation schemes on which Sir William Willcocks is at present engaged. [86] It is known as the ’Amalîyeh Mukallifeh. [87] This applies, I believe, only to lands leased from the State, arḍîyeh amîrîyeh. [88] The foundations were, however, traced by Dieulafoy, who has indicated them in his plan: _L’Art ancien de la Perse_, Vol. V. When he first visited Ctesiphon, the east wall of both wings and all the vault of the hall were perfect. [89] It was founded by Anushirwân the Just after he had taken Antioch of Syria in 540. He transported the inhabitants of Antioch to the Tigris and settled them opposite Seleucia in a new city which is said to have been built on the plan of Antioch. Le Strange: _Lands of the Eastern Caliphate_, p. 33. [90] _Sûrah_, XIV. vs. 46. The Arabs called the double town Medâin, the cities, but Ṭabarî uses the name for the eastern city and describes the western as Bahurasîr. I have abridged Ṭabarî’s account of the siege from the text of de Goeje’s edition, Vol. V., Prima Series, under the years 15 and 16 A.H. [91] The White Palace is not represented by the existing ruin on the east bank, which was known to the Arabs as Aywân Kisrâ, the hall of Chosroes. The White Palace was also on the left bank, but about a mile higher up. It had disappeared by the beginning of the tenth century. Le Strange, _op. cit._, p. 34. [92] Bricks stamped with Nebuchadnezzar’s name have been found along the quays, and there was a flourishing Persian Baghdâd on the west bank of the Tigris towards the end of the Sassanian period. The chief authority for the history of Baghdâd is Mr. Le Strange’s admirable book, _Baghdâd during the Abbâsid Caliphate_, which has made it possible to understand the very complicated topography of the town. [93] It is perhaps unnecessary to explain that the Shî’ahs regard ’Alî ibn abî Tâlib, who lies buried at Nejef, as the only lawful khalif. He and his eleven immediate heirs are known as the Twelve Imâms, the twelfth being Muḥammad III al Mahdî, who is credited with having been concealed in a cave at Sâmarrâ whence he will emerge at the end of days and re-establish the true faith.