The age of firearms, however, which brought the death-blow to medieval siegecraft, was long in coming; and meanwhile the progress of the science of attack depended upon the improvement in methods which could be employed only in close proximity to the besieged stronghold, or within a very limited range. Engines for hurling stones or javelins increased in size and strength. Devices were brought into play for scaling or undermining the defences of the town or castle. The attack was directed against the defences rather than against the defenders. A casual stone might do injury to the medieval soldier, or an arrow might pierce between the joints of his harness; but his armour, which became more heavy and more carefully protected as the chance of risk from such missiles increased, made loss of life in the course of a siege a misfortune rather than an inevitable contingency. His first anxiety, therefore, was to make the defensive works which sheltered him impregnable. As the enemy multiplied his designs against the palisaded enclosure, the palisade gave place to the stone wall; as the enemy’s means for prosecuting his attempts increased in power, the wall increased in height and strength; and at last, during the transitional epoch in which firearms gradually superseded the older and more primitive weapons of attack, the wall presented to the besieger a thoroughly guarded front which rendered his medieval siege tactics obsolete, and called for new developments in his craft. The progress of fortification under these conditions will be the subject of the remaining chapters of this book, with special reference to the castle, in the defences of which the military engineers of the middle ages displayed the epitome of their science. Before we proceed, however, to the growth of the stone-walled castle, some description is necessary of the improvement in siege-engines and methods of attack by which its development was governed. It must be kept in mind that the siegecraft of the middle ages advanced upon lines that were by no means new. Its engines, its devices for breaking down or scaling walls and towers, were not new inventions, but relics of Roman military science. With the decay of the Roman power in western Europe, these materials of warfare, unknown to the Teutonic conquerors of Britain, had fallen into disuse. Preserved in the east by the Byzantine empire, the inheritor of Roman civilisation, they became familiar to the barbarians who overran Europe in the dark ages; and their revival in the parts of Europe most remote from the historic centres of Roman influence was due in no small measure to the adoption of traditional siegecraft by the invading tribes which had come into conflict with Byzantine strategy. So far as England is concerned, the first advance in the art of attack was the direct result of the Norman conquest; while subsequent improvement in western Europe generally was primarily due to the knowledge of eastern