Peaceful fraternity was thus turned into a wild lust for conquest; the Karmathites succeeded in dominating a great part of Arabia and the mouth of the Euphrates, and in A.D. 920 extended their ravages westwards. They took possession of the holy city of Mecca, in the defence of which 30,000 Moslems fell. "For a whole century," says von Hammer, "the pernicious doctrines of Karmath raged with fire and sword in the very bosom of Islamism, until the widespread conflagration was extinguished in blood." But in proclaiming themselves revolutionaries the Karmathites had departed from the plan laid down by the originator of their creed, Abdullah ibn Maymūn, which had consisted not in acts of open violence but in a secret doctrine which should lead to the gradual undermining of all religious faith and a condition of mental anarchy rather than of material chaos. For violence, as always, had produced counter-violence, and it was thus that while the Karmathites were rushing to their own destruction through a series of bloody conflicts, another branch of the Ismailis were quietly reorganizing their forces more in conformity with the original method of their founder. These were the Fatimites, so-called from their professed belief that the doctrine of the Prophet had descended from Ali, husband of Fatima, Mohammed's daughter. Whilst less extreme than the Karmathites, or than their predecessor Abdullah ibn Maymūn, the Fatimites, according to the historian Makrizi, adopted the method of instilling doubts into the minds of believers and aimed at the substitution of a natural for a revealed religion. Indeed, after the establishment of their power in Egypt, it is difficult to distinguish any appreciable degree of difference in the character of their teaching from the anarchic code of Abdullah and his more violent exponent Karmath. The Fatimites