Peter's Rock in Mohammed's Flood. By Thomas W. Allies. (Burns
and Oates.)—This is the seventh and completing volume of Mr. Allies's thoughtful and learned work on " The Formation of Christendom." It takes in the period from the death of Pope Gregory the Great, to the coronation of Charlemagne by Pope Leo III. on Christmas Day, 800. It is concerned, as the title indicates, with the relations between Christendom and Islam, with the character of Mahommed (of which Mr. Allies takes a very un- favourable view), the attitude of the Popes to the Eastern Empire and to the successive masters of Italy, and finally, with the establishment of the Holy Roman Empire. We differ seriously from many of the historian's conclusions, while willingly acknow- ledging his industry, the wide range of his knowledge, and the general value of his contribution to the history of the time.