Canadian Historic Sites: Occasional Papers in Archaeology and History No. 17

The Halifax Citadel, 1825-60: A Narrative and Structural History

by John Joseph Greenough

Now, here, you see, it takes all the running
you can do, to keep in the same place.
If you want to get somewhere else, you
must run at least twice as fast as that!

(Through the Looking Glass, Lewis Carroll)

Glossary of Fortifications Terms Used in this Report

Arch: The crown of an arch is the highest or central part; the spring is the point at which the arch connects with the wall.

Banquet(te): A raised path along the inside of a ditch or parapet on which soldiers may stand to fire at the enemy.

Bastion: A projecting part of a fortification, usually pentagonal; one side opens into the main body of the work.

Caponer: A covered structure permitting flanking fire to cover the ditch.

Casemate: A vaulted room, used for a variety of purposes (barrack accommodation, storage, artillery etc.). Frequently built under ramparts (q.v.).

Casemate of defence: A casemate behind the counterscarp embrasured, and mounting guns to cover the ditch.

Casemate of reverse fire: An arched structure behind the counterscarp and opposite a salient (q.v.). provided with embrasures to flank the ditch.

Cavalier: A heavily constructed building, usually higher than the other works, which mounts a battery on its flat roof covering the ground around the fort.

Countermine: A chamber or gallery dug under the glacis (q.v.). containing a charge of gunpowder which may be blown up as an enemy approaches. Also a tunnel dug to obstruct an enemy who is trying to dig under and blow up a wall.

Counterscarp: The outer wall of a ditch, facing the escarp and the fort itself.

Covert way: A road running around the outside of the ditch, protected by its own parapet, used to cover the glacis and to move men and equipment around the fort under the fort's protection.

Curtain: Any wall which connects two bastions.

Demi-bastion: A bastion with two faces and only one side, built in the form of a quadrilateral. One side opens into the fortification.

Dos d'ane: A peaked construction, shaped like a gable roof, built up over an arch in order to shed water.

Embrasure: An opening cut for cannon, either into a wall or the ramparts. Usually cut at an angle to give maximum covering fire.

Epaulment: A mass of earth raised to protect troops from enemy fire.

Escarp (or scarp): The inside wall of a ditch, facing away from the fort.

Flank: Any part of a fort designed to protect another part, usually by being angled in such a way that fire can be directed in a wide arc.

Gallery: (1) An underground passage behjnd the counterscarp, loop-holed for musketry, covering the ditch; (2) the underground passage to a countermine (q.v.).

Glacis: A long, gentle slope leading up to a fortification from the surrounding country, covered by fire from the fortification.

Gorge: Literally, throat. The inside of a bastion or ravelin, facing the interior of the fort; the area not provided with ramparts. Usually at ground level.

Magazine: A heavily built structure in which gunpowder is stored.

Parapet: A low wall built to protect defenders, either from gunfire or from falling off the top of a rampart, cavalier or other raised work.

Place d'armes (place of arms): A widened area in the covert way, usually close to the body of the work, where mobile artillery may be concentrated.

Rampart: A mound of earth piled up for defending a place, capable of resisting artillery fire. It should be wide enough on top to allow troops and guns to pass. In the case of the Citadel, the rampart is the main wall of the work, just inside the ditch.

Ravelin: A triangular work, built outside the ditch and in front of the curtain, with two faces. Frequently flanks the bastions and ditch.

Redan: A simple work with two faces, triangular and open in back, which faces toward an attacker.

Re-entering angle (re-entrant): Any angle pointing toward the inside of the fort.

Retaining wall: Any wall built to enclose and support the face of a body of earth (e.g., a dike, ditch, shoulder or rampart).

Revetment: The retaining wall of a rampart.

Salient angle (salient): Any angle pointing away from a fortification, toward the glacis.

Sally port (postern): An opening in the main body of a fortification, other than the main gate, allowing troops to pass toward the enemy. Usually (and necessarily) very well defended.

Shifting room: There is no accepted definition of this term. For the purposes of this report, the shifting room is a casemate in a magazine, probably used for moving powder and possibly for loading shells with powder.

Terreplein: (1) A level surface on which guns may be mounted (e.g., the top of a cavalier, covered with earth); (2) the surface of a rampart behind the parapet; (3) any sloping bank of earth behind a wall.

Trace: The general ground-plan of a fortification.