GLOSSARY OF MINING TERMS(A)

A.B. Meco-Moore The A.B. Meco-Moore was a joint development of Anderson Boyes and the Mining Engineering Companies, hence the name. The first genuine cutter-loader machine developed to perform two operations simultaneously on a longwall face and therefore did away with any need for blasting.

A-Force to hole a board into an adjoining board unintentionally, (N.East).

Abandonment plans plans required by law to be deposited with the authorities upon the closure of a coalmine, or section of a mine. They must be durable, and show the workings in relation to surface features and record information with respect to orientation, contours, scales, boundaries, faults, etc. The plans must also show the last recorded workings for the safety of any future operations.

Abutment an area of unworked coal or of consolidated waste bounding a working area and which carries the strata over the workings. Also zones of stress concentration resulting from excavation e.g. along the sides of roadways and in front of the coalface.

Adit a more or less horizontal entrance to a mine usually constructed such that water will run out of it; a walkable outlet from the mine workings to the surface. Sometimes a dipping tunnel following the seam down from its outcrop. Also known as a day-level, day-eye or day-hole.

Advanced head or Advanced heading a heading in advance of the coalface often known as a ‘pilot heading’ or ‘advanced gate’.

Advancing Face – see Face

Aerophor Breathing Apparatus The Aerophor was introduced in 1910. The apparatus supplied oxygen from a liquid air source. The liquid air container and regenerator were carried on the back, and the breathing bag was worn on the chest. The overall weight of the apparatus was about 40 lbs.

Afterdamp a mixture of non-inflammable gasses left after an explosion or fire in a coalmine. It usually has a high carbon monoxide (CO) content and is very low in oxygen. Afterdamp was responsible for more deaths among miners than were actually physically injured due to the explosions. Also known as ‘azote’, (N.East).

Agent In pre-nationalisation days the chief official of a large coalmine or group of mines under the same ownership was known as an Agent.

Air the current of air circulating through and ventilating a mine.

Air bagging, -see Bagging

Air box, a square wooden tube used to convey air into the face of a single drift, or shaft in sinking.

Air bridge, -see Air crossing.

Air course, an underground tunnel or passage used solely or mainly for ventilation.

Air coursing, a system of ventilation introduced in about 1760, in which the air current was directed through all the underground roadways of the mine before going to the upcast shaft. The system necessitated the building of stronger stoppings, brick was now being brought into use, and better fitting doors.

Air crossing, a bridge constructed to allow the return airway to pass either under (undercast) or over (overcast) the intake airway. The air crossing must be made airtight to avoid the mixing or short-circuiting of either of the two air-currents. It should also be constructed in such a manner as to by able to withstand the results of an explosion. Also called an ‘air bridge’.

Air doors, -see Doors.

Airdox, an appliance for breaking down coal by the release of high-pressure air at the back of a shothole.

Air head, a drift of small dimensions used for ventilation. (S.Staffs.).

Air-leg support, a compressed air appliance that consisted of a steel cylinder and an air-operated piston that enabled one man to support and advance a heavy drilling machine during drilling operations.

Air-lock, a casing at the top of an upcast shaft to minimise surface air leakage to the ventilation fan.

Air sampling, the taking of air samples at predetermined points throughout the mine workings for later analysis in the laboratory.

Air shaft or Air pit, a shaft used wholly, or mainly, to ventilate a mine. Old shafts were often used as an additional upcast or downcast air passage.

Air slit, -see Stenton

Air splitting, refers to ventilation and the practice of splitting the intake air current into a number of individual air circuits, each one ventilating a certain district of the underground workings, and each one of the splits having a separate intake and return.

Airstream helmet, a type of helmet used in modern mining. The helmet has a small fan, which pulls air up the back of the helmet through a filter. The air is redirected down the front onto the face of the wearer.

Airway, an underground tunnel (or roadway) commencing or terminating at a shaft or outlet to the surface, or any roadway used for the passage of air.

Alighting station, a platform where men leave a man-riding belt.

Amain, Waggons or tubs are said to run amain if they get by accident over an incline bank head without the rope being attached; or through the rope becoming detached or broken, (N.East).

Anchor, iron bars of various shapes and sizes used to lock the wheels of coal tubs.

Anchor prop, a prop, set at an angle between the roof and floor, on the coalface to act as an anchor for the main and tail ropes, when manoeuvring short and longwall cutting machines.

Anchor station, a device, usually hydraulic, which prevents uncontrolled movement of the delivery or return end units of a conveyor.

Anderton shearer-loader, an adaptation of the Anderton longwall cutter in which the jib of the cutter was replaced by a shearer drum which was capable of cutting a web of variable depth. The machine, introduced in 1952, rode on top of an armoured conveyor and needed a prop-free-front for working. The first shearers cut coal in only one direction. The machine was then flitted back along the face, loading any loose coals by using a plough deflector. Later models were capable of cutting coal in both directions and became bi-directional, and were known as ‘bi-di’s’.

Andra, a heading driven in a diagonal direction with respect to the cleat, neither ‘end’ nor ‘bord’. (Yorks.).

Ankerite, an iron magnesium carbonate mineral found in some coal cleats.

Anthracite, a high rank bituminous coal, a natural smoke-less fuel. Also known as ‘Stone’, ‘Kilkenny’ or ‘Crow coal’.

Antitpopal ventilation, ventilation by a current of air travelling in the opposite direction to that of the flow of the coal out of the mine.

Arc Shearer, a coal cutter that cuts at any required angle, but usually horizontally and/or vertically. (S.Staffs.).

Arch girders or Arches, a length of ‘H’ rolled steel joist, bent to a semi-circular shape. Two or more sections would be fitted together by using bolts and fishplates to make up an arched shaped roof support for the roadways in a mine. - see also Rings.

Arles or Earles, a ‘golden handshake’ or bounty paid to miners on joining to work in a mine in times of short supply of labour, binding the miner to that mine, pre 1844, (N.East).

Armoured Flexible Conveyor (AFC) or Snaking Conveyor. The A.F.C. was developed in Germany by the Gewerkschaft Eisenhutte Westfalia during W.W.2. A few units were tried out in Britain shortly after the war and by the sixties they were being installed on all the major longwall faces in Britain. Designed to carry a coal cutter, cutter-loader or to guide and hold a plough against the face. The A.F.C. is used on a prop free front and by using horizontal hydraulic rams, attached to powered supports, can be advanced (snaked over) behind the machine as it progresses along the face thereby preparing the face for the machine's immediate return run. The A.F.C. was also used on hand-filled faces. A heavy duty chain-type conveyor, the A.F.C. was nicknamed the ‘Panzer’ short for Panzerforderer by the miners.

Arms, upright props, also called ‘uprights’.

Arse flap or Arse loop, a loop attached to the winding rope in which a man sat when carrying out repair work in the shaft. If it was fitted with a board to sit on it was known as an ‘arse flap’. (Yorks), (N.East).

Ascensional ventilation or Antitropel ventilation, a system for ventilation in a mine in which the intake air is directed to the lowest point in the mine workings then ascends along the faces to the main return. The uphill flow of the air is assisted by it being heated as it travels along the faces and through the mine workings. This system is advantageous in gassy mines as firedamp also tends to flow upwards.

Ash content, the percentage of incombustible material in coal. That portion of a laboratory sample remaining after heating under standard conditions to a constant weight, i.e. until all combustible matter as been burned away.

Auxillary fan, a fan used in conjunction with air ducting to increase the ventilation to a section of the mine.

Awn, a cleavage or cleat in the coal at 45º to the main and butt cleats. The ‘long awn’ and ‘short awn’ are intermediate cleat directions, nearer respectively to the ‘bord’ and ‘end’ directions, i.e. < and > 45º to the main cleat.

Azote, -see Afterdamp.

Back to list of Pit Terminology