on receiving this, the insurgents vacated the city, and were shortly afterwards entirely defeated by the caliph's forces. A wonderful story is told of the great earthquake which took place in the year 846 A.D. : namely, that in the night, the guards of the Cubbet es Sakhrah were suddenly astonished to find the dome itself displaced, so that they could see the stars and feel the rain splashing upon their faces. Then they heard a low voice saying gently, " Put it straight again," and gradually it settled down into its ordinary state. The power of the caliphs was now upon the wane : the disorders consequent upon the introduction of Turkish guards at Baghdad by El Mo'tassem first weakened their authority; but the revolt of the Carmathians in 877, during the reign of El Mo'tammed Billah, struck the first fatal blow against the House of Abbas. The sect of the Carmathians was founded by a certain Harndan, surnamed Carmat. His doctrines consisted in allegorising the text of the Cor'an and the precepts of Islamism, and in substituting for their exterior observance other and fanciful duties. Carmat was an inhabitant of the neighbourhood of Basora, and his sect took its origin in that place, and soon spread over the whole of Irak and Syria. Under a chief, named Abu Tâher, these fanatics defeated the Caliph el Moktader Billah, and held possession of the whole of the Syrian desert. With a force of more than a hundred and seven thousand men, Abu Tâher took Bakka, Baalbekk, Basra, and Cufa, and even threatened the imperial city of Baghdad itself. The caliph made strenuous exertions to suppress the rebellion, but his soldiers were defeated, and his general taken captive and treated with the utmost indignities. A strange story is told of this struggle, which illustrates the fierce fanaticism and blind devotion of Abu Tâher's followers. A subordinate officer from the Mussulman army penetrated to the rebel camp, and warned the