MEDIEVAL LIFE IN EUROPE 297 plosive, and believed in the possibility of mechanically pro- pelled vehicles, as the following remarkable passage from his writings reveals :— 1 Machines for navigating are possible without rowers, so that great ships suited to river or ocean, guided by one man, may be borne with greater speed than if they were full of men. Likewise, cars may be made so that without a draught animal they may be moved-----as we deem the scythed cha- riots to have been from which antiquity fought. And flying machines are possible, so that a man may sit in the middle turning some device by which artificial wings may beat the air in the manner of a flying bird/ Among the writers of the age we have space only for a few observations on the greatest. The most famous among the earliest was St. Augustine, the Bishop of Hippo. His The City