some fifteen years after the event, and in the reign of Al Māmūn, would say; for the siege of Mecca was then, in point of fact, the last which had taken place, under the insurgent, Abu Sarāya, in the year 200 A.H. Had the Apology been written later on, say in the fourth century, the "latest attack" on Mecca would not have been that of Abu Sarāya, but of Soleimān Abu Tāhir in 317 A.H. So also, in illustrating the rapine and plunder of the early Moslem campaigns, Al Kindy mentions, as of a similar predatory and ravaging character, the insurrection of Bābek Khurramy, and the danger and anxiety it occasioned thereby "to our lord and master the Commander of the Faithful." This rebellious leader, as we know, had raised the. standard of revolt in Persia and Armenia some years before, routed an army of the Caliph, and long maintained himself in opposition to the imperial forces; and the notice, as one of an impending danger then occupying men's minds, is precisely of a kind which would be natural and apposite at the assumed time, and at no other.1 Once more, in challenging his friend to produce a single prophecy which had been fulfilled since the era of Mahomet, he specifies the time that had elapsed as "a little over 200 years," and uses the precise expression to denote the period, which one would expect from the pen of a person writing about the era,