Cavalier, earthwork raised in the middle of a bastion, or upon any point of the defence, to command the exterior. In the sixteenth century the besieging armies erected cavaliers around defences to mount cannon upon them. Our siege batteries are the modern analogues of these works (see p. [237], [312]).
Chemise, exterior inclosure of a donjon; the chemise of the donjon consists of a wall which leaves a space of some yards between it and the donjon. A postern with a drawbridge gives a communication between one of the rooms of the donjon and the rampart walk of the chemise (see p. [201]).
Clavicula (Latin), exterior defence, raised outside the gates of a camp, and which obliged those who endeavoured to enter to present their flank to the defenders of the ramparts (see p. [92]).
Covered Way, road formed on the counterscarp and protected by the relief of the glacis (see p. [308]).
Counterscarp, is the casing of the ditch which is opposite to the defence.
Demi-lune, low work, disposed before a curtain between two bastions, separated from the main body of the fortress by a ditch, and possessing two faces and two short flanks (see p. [306]).
Donjon or Keep, chief retreat of the defenders of a strong castle. The donjon was always separated from the defences of the castle, and put in direct communication with the exterior (see p. [169]).
Escarp is that part of a revetment of fortifications which fronts the exterior, from the bottom of the ditch to the parapet or crenelation.
Fausse-Braie, palisade or trench, with parapet, defending the bottom of the ditch, low enough to be masked by the relief of the counterscarp.
Glacis, sloping ground which extends from the counterscarp of the ditch towards the country, and masks the covered ways as well as the escarp.