ABSTRACT
The result of contact, during the Crusades, with the civilization of the East was that the Crusaders learned many useful arts and crafts, which they brought back with them. In particular, the science of fortification, the arts of attack and defence, were understood and practised with far greater elaboration and skill by the ingenious Byzantines and Saracens than by the rough feudal knighthood of Britain or France. In the Norman stone castles the principal feature was the rectangular tower or keep. The master of work would then engage a master mason, who was responsible for the design and erection of the stonework of the castle. Many moated stone manor-houses still survive in England. The attack and defence of fortifications was a highly scientific business, and it was better to have a castle of manageable size, defended by a small garrison of picked and trained men, than one which needed a mob of untrained feudal levies.
