Fortress: A History of Military Defence

armoured Army artillery assault attack bailey bastion became began besieged bomb bomb-proof bombardment breach Brialmont built cannon caponier casemate Castle century citadel coast defence Coehorn concrete construction counterguard counterscarp covered crownwork cupolas curtain detached detonated developed ditch Douaumont earth earthwork effect enemy engineers entrance escarp excavated explosive feature feet fire flanks fleet Fort Widley fortification fortress forts French front garrison German glacis gorge ground Gruson hornwork howitzers Ian Hogg Imperial War Museum infantry iron Japanese Krupp land Liège line of defence lunettes machine guns Maginot Line masonry metres Mike Jarvis mortar mound mounted musketry obstacle outer outworks parallel parapet plans plate polygonal Port Arthur projectiles protected rampart ravelin rear face redoubt reinforced roof Russian salient angle saps shell ship shot side siege slope structure Superior Slope surrounding tenaille terreplein thick tower troops tunnels turret Vauban wall weapons yards