Christian church.[403] Neither was there in ‘Amr’s mosque any miḥrâb to mark the qiblah; it was not until the third enlargement of the mosque in A.D. 710 that the qiblah wall was given a miḥrâb. It is further recorded that the orientation adopted by ‘Amr was imperfect, so that the worshippers were obliged to stand askew that they might face truly towards Mekkah while they prayed. The mosque was provided with six doors, two in each wall, with the exception of the qiblah wall, which was left unbroken. The first enlargement of the building took place in A.D. 673, on which occasion an open space, or court, was added to the north. In the second enlargement (A.D. 698-699) the mosque was entirely rebuilt and the ṣaḥn was included within its walls. It appears from these accounts that by the middle of the Umayyad period the development from courtyard-house to sanctuary was complete. Its course had been simple and obvious. All the essentials of the stereotyped form were present at Medînah; the differences were differences in size and splendour, not in kind. The domestic court had become the ṣaḥn; the palm-leaf sheltering roofs against the qiblah wall and in one angle of the court had solidified into the riwâqs; the palm-trunk columns had been replaced by columns or piers of brick (possibly by brick columns at Medînah itself as early as the time of ‘Umar), or, where the spoils of Sasanian and Byzantine lay ready to hand, as at Kûfah or Fusṭâṭ, by columns of marble. The qiblah had been given a visible shape in the miḥrâb niche, and by the close of the Umayyad period the minbar had wholly lost its temporal attributes and had taken its place as part of the necessary furniture of the mosque, though it probably still continued to be a movable wooden structure. Such a sanctuary, but reduced to the modest dimensions of a private chapel (if I may be permitted the phrase), is the mosque of Ukhaiḍir. The fact that its orientation is inexact--Mekkah lies to the south-east of Ukhaiḍir, whereas the direction indicated by the miḥrâb is almost due south--would not have been regarded as of much importance. As has been mentioned, ‘Amr’s mosque had the same defect, and in this respect Manṣûr’s mosque at Baghdâd offers a yet more significant parallel. Ṭabari observes that the mosque in the round city was not properly oriented because it was built to fit the qaṣr, whereas at Ruṣâfah the orientation was right, because the mosque was built before the qaṣr.[404] Precisely the same explanation applies to the Ukhaiḍir mosque. The palace builders were accustomed to square their plans to the points of the compass, and a miḥrâb in the south wall was the closest approximation which could be obtained in an edifice which lay north and south. The mosque was so small that there was no difficulty in applying to it the system of vaulting which reigns over the whole palace, but the massive Mesopotamian vault was unsuited to free-standing columns and the roof of the riwâqs has fallen.