The revolution of 750 A. D. was heralded and followed by earthquakes, which were no doubt regarded as omens. The Dome of the Rock, standing on sure foundations, appears to have escaped any serious damage, but the Aḳṣa Mosque was ruined, the west wall falling--according to later accounts[466]--about 746 A. D., and the east wall about 755 A. D. We may probably understand by these statements that the great apse and the atrium of Justinian’s church, not being founded on rock, were overthrown; and the mosque was still in ruins in 770 A. D. The restoration was begun by El Manṣûr, the second of the khalifs of Baghdâd, and was mainly carried out under his son and successor El Mahdy, after 775 A. D. The fourteenth-century account of this restoration states that El Mahdy made the building “shorter and broader”; and El Muḳaddasi, describing it two centuries after its restoration, says that “the more ancient portion remained like a beauty spot in the midst of the new, and it extends as far as the limit of the marble columns; for beyond, where the columns are of concrete (or plaster), the later building begins.” This account seems clearly to apply to the present Aḳṣa Mosque, which, as de Vogüé perceived,[467] was “preceded by a Christian church, of which the ruins were the nucleus for the Arab constructions.” For there is a marked contrast between what is called the “transept,” or south part of the mosque, and the ruder work of the northern nave and aisles. The building was made shorter by the disappearance of the great atrium on the west, and broader by building the nave on the north. The only subsequent alterations of plan were those of the Templars in the twelfth century. They added a great refectory to the west, on the site of the south part of the original atrium, with a fine Norman porch still standing on the north, and a long vestry on the south Ḥaram wall just east of the church.