Leonard - Beneath the Killing Fields: Exploring the Subterranean Landscapes of the Western Front

Bell Chamber

A bell dome-like chamber that can form in a tunnel or dugout when chalk has slabbed from the sides and ceiling.

Blowing

A term used to describe the detonation of a mine charge.

Camouflet

An underground explosive charge primarily employed to destroy enemy tunnels. Camouflet charges do not usually break the surface.

Clay Kicking

The practice of digging through clay, originally devised by sewer diggers. Clay kicking has the added advantage of being near silent and was therefore a logical adoption for tunnelling companies where the geology was relevant.

Light (Decauville) Railway

Invented by Paul Decauville (1846-1922), the railway named after him consisted of narrow gauge tracks mounted to metal sleepers. It was light and manoeuvrable and used extensively during the First World War for the transport of men and equipment on the front lines.

Exteroception

Outwardly orientated perception.

Face

A face is the front of the tunnel where the actual digging was being done, similar to a coal face.

Gallery

A term used to describe a tunnel, usually one that extended towards the enemys positions.

Geophone

A tool used for listening underground. Consisting of two microphones and acting in a similar way to a doctors stethoscope. Sound waves through the ground are magnified and sounds are transmitted to each of the listeners ears, allowing a bearing to be taken on the source of the sound.

Incline

A sloping entrance to a tunnel, usually from a trench and used instead of a vertical shaft. Inclines are often referred to as shafts in war diaries.

Kinaesthesia

The sensation of movement in the body and limbs originating in the muscles, tendons and joints.

Lateral

A defensive tunnel dug parallel to the front line trench. Other, offensive and defensive, tunnels were then dug from the lateral. Sometimes also called a transversal.

Livens Projector

A type of mortar used primarily for delivering gas.

Mine

An explosive charge placed underground.

Pioneer Shaft

An exploratory shaft dug to connect existing features.

Proto Apparatus

Self contained breathing apparatus primarily used in mine rescue.

Proprioception

The perception of the position, state and movement of the body.

Puit

Shaft connecting the surface to a souterraine used to lift up and remove cut chalk blocks from the original quarry.

Russian Sap

A shallow tunnel or deep covered trench that could quickly have the top pulled in to expose a trench, listening post or trench mortar position.

Sap

A trench dug towards the enemy. Also sometimes used to describe a tunnel dug in a similar direction.

Seismomicrophone

An electrically powered sound detector usually linked to a central listening station responsible for a large area of front.

Sensorium

The section of the human brain tasked with the reception and interpretation of the different sensory stimulae. Also a term used to describe the human senses as a whole.

Shaft

A vertical entrance to a tunnel or dugout but often used to describe an incline.

Slabbing

Chalk is often layered in bedding planes and where these are weak large sections can split apart, causing collapses.

Souterraine

A French term meaning underground but often a term used to describe caves or subterranean quarries.

Stollen

A German term for a mine gallery, deep dugout or tunnel.

Subway

A communication tunnel used for the movement of troops to and from front line positions. Subways also often included command and signal centres, accommodation and logistic facilities.

Synaesthesia

Literally the ability for the senses to hear colour or see music and smell shapes. Also synaesthesia is the ability for one sense to trigger another, for example music may trigger a memory associated with it which will trigger the taste buds to remember what was eaten when listening.

Tamping

Tamping is the term given to the fill placed behind a mine charge to avoid the blast funnelling back up the tunnel. Sandbags filled with spoil, or just spoil by itself along with large chunks of chalk, were usually used, piled to the ceiling and extending for several metres. A space was then left and the process repeated again, the number of times dependent on the size of the charge.