GLOSSARY OF MINING TERMS.
[After damp.] The mixture of gases resulting from the burning of fire damp.
Air shaft. A vertical opening into a mine for the passage of air.
Airway. Any passage in the mine along which an air current passes; but the term is commonly applied to that passage which is driven, for ventilating purposes, parallel to and simultaneously with the gangway.
Anticlinal. A fold of strata in which the inclination of the sides of the fold is from the axis downward.
Barrier pillars. Large pillars of coal left at a boundary line, or on the outskirts of a squeeze.
Basin. The hollow formed by a fold of the seam; any large area of included coal.
Battery. In steep-pitching seams, a wooden structure built across the shute to hold the mined coal back.
[Bearing in.] Cutting a horizontal groove at the bottom or side of the face of a breast.
Bed. Any separate stratum of rock or coal.
Bench. A horizontal section of the coal seam, included between partings of slate or shale.
Black damp. Carbonic acid gas; known also as choke damp.
[Blossom.] Decomposed coal, indicating the presence of an outcrop.
Blower. A forcible and copious discharge of gas from a cavity in the coal seam.
Bony coal. Coal containing in its composition slaty or argillaceous material.
Bore-hole. A hole of small diameter drilled or bored, either vertically or horizontally, through the measures or in the coal; usually, a hole drilled vertically for prospecting purposes.
Brattice. A partition made of boards or of brattice cloth, and put up to force the air current to the face of the workings.
Breaker. A building, with its appliances, used in the preparation of anthracite coal for the market.
Break-through. A cross-heading or entrance, used in the bituminous mines.
[Breast.] The principal excavation in the mine from which coal is taken; known also as chamber.
Broken coal. One of the regular sizes of prepared anthracite.
Buckwheat coal. One of the regular sizes of prepared anthracite.
Buggy. A small car or wagon used for transporting coal from the working face to the gangway.
Buntons. The timbers placed crosswise of a shaft down its entire depth, dividing it into vertical compartments.
Butt. In bituminous coal seams, the vertical planes of cleavage at right angles to the face cleavage.
Butty. A comrade; a fellow-worker in the same chamber.
Cage. See [Carriage.]
[Carriage.] The apparatus on which coal is hoisted in a shaft.
Cartridge pin. A round stick of wood on which the paper tube for the cartridge is formed.
Cave-hole. A depression at the surface, caused by a fall of roof in the mine.
Chain pillars. Heavy pillars of coal, lining one or both sides of the gangway, and left for the protection of that passage.
Chamber. See [Breast.]
Chestnut coal. One of the regular sizes of prepared anthracite.
Choice damp. See [After-damp.]
Cleavage. The property of splitting on a certain plane.
Collar. The upper horizontal crosspiece uniting the legs in the timbering of a drift, tunnel, slope, or gangway.
Colliery. All the workings of one mine, both underground and at the surface.
Conglomerate. The rock strata lying next beneath the coal measures.
Counter-gangway. A gangway which is tributary to the main gangway, and from which a new section of coal is worked.
Cracker boss. The officer in charge of the screen room in a breaker.
Creep. A crush in which the pillars are forced down into the floor or up into the roof of the mine.
Cribbing. The timber lining of a shaft, extending usually from the surface to bed-rock.
Crop-fall. A caving in of the surface at the outcrop.
[Cross-heading.] A narrow opening for ventilation, driven through a wall of coal separating two passages or breasts.
[Crush.] A settling downward of the strata overlying a portion of an excavated coal seam.
Culm. All coal refuse finer than buckwheat size.
[Dip.] The angle which any inclined stratum makes with a horizontal line.
[Door boy.] A boy who opens and shuts the door placed across any passageway in the mines to control the direction of the ventilating current.
Double entry. One of the systems by which openings into the bituminous coal mines are made.
Downcast. The passage or way through which air is drawn into a mine.
Drift. A water-level entrance to a mine, driven in from the surface on the coal.
Drill. Any tool used for boring holes in the rock or coal.
Driving. Excavating any horizontal passage in or into the mines.
Drum. A revolving cylinder, at the head of any hoisting-way, on which the winding rope is coiled.
Egg coal. One of the regular sizes of prepared anthracite.
Entrance. See [Cross-heading.]
Entry. The main entrance and traveling road in bituminous mines.
Face. The end wall at the inner or working extremity of any excavation in or into the mines. In bituminous mines the vertical plane of cleavage at right angles to the butt cleavage.
Fan. A machine used to force a ventilating current of air through a mine.
Fault. A displacement of strata in which the measures on one side of a fissure are pushed up above the corresponding measures on the other side.
Fire-board. A blackboard, fixed near the main entrance of a mine, on which the fire boss indicates each morning the amount and location of dangerous gases.
Fire boss. An official whose duty it is to examine the workings for accumulations of dangerous gases.
[Fire clay.] The geological formation which is usually found immediately underlying a coal bed.
Fire damp. Light carbureted hydrogen.
Fissure. A separation of rock or coal across the measures.
Floor. The upper surface of the stratum immediately underlying a coal seam.
Gangway. An excavation or passageway, driven in the coal, at a slight grade, forming the base from which the other workings of the mine are begun.
Gas. Fire damp.
Gob. The refuse separated from the coal and left in the mine.
Guides. Narrow vertical strips of timber at each side of the carriage way in shafts, to steady and guide the carriage in its upward or downward movement.
Gunboat. A car used for hoisting coal on steep slopes.
Head-frame. The frame erected at the head of a shaft to support the sheaves and hold the carriage.
Heading. Synonymous with gangway. Any separate continuous passage used as a traveling way or as an airway.
Hopper. A feeding shute or pocket in a breaker.
Horseback. A small ridge in the roof or floor of a coal seam.
Inside slope. An inclined plane in a mine, on which coal is hoisted from a lower to a higher level.
Jacket. One of the sections or frames of wire mesh of which a revolving screen is made up.
[Keeps.] Projections of wood or iron on which the carriage rests while it is in place at the head of the shaft.
Lagging. Small timbers or planks driven in behind the legs and over the collars to give additional support to the sides and roof of the passage.
Legs. The inclined sticks on which the collar rests in gangway, tunnel, drift, and slope timbering.
Lift. All the workings driven from one level in a steep-pitching seam.
Loading place. The lowest extremity of the breaker, where prepared coal is loaded into railway cars.
Lump coal. The largest size of prepared anthracite.
Manway. A passageway in or into the mine, used as a footway for workmen.
Mouth. The opening, at the surface, of any way into the mines.
Needle. An instrument used in blasting coal, with which a channel is formed through the tamping for the entrance of the squib.
Nut coal. One of the regular sizes of bituminous coal.
Opening. Any excavation in or into a mine.
Operator. The person, firm, or corporation working a colliery.
Outcrop. That portion of any geological stratum which appears at the surface.
Output. The amount of coal produced from any mine, or from any area of country.
Parting. The layer of slate or bony coal which separates two benches of a coal seam.
Pea coal. One of the regular sizes of prepared anthracite.
Picking shute. A shute in the breaker from which the pieces of slate are picked out by a boy as they pass down with the coal.
Pillar. A column or body of coal left unmined to support the roof.
Pillar and breast. The name of a common mining method.
Pinch. See [Crush.]
Pitch. See [Dip.]
Plane. Any incline on which a track is laid for the purpose of lowering or hoisting coal.
Pockets. Receptacles at the lower ends of shutes, in breakers, from which coal is loaded into railway cars.
Post. A wooden prop to support the roof in bituminous mines.
Prop. A timber set at right angles to the seam, in anthracite mines, to support the roof.
Prospecting. Searching for indications of coal on the surface, and testing coal seams from the surface.
Pump way. That compartment of a shaft or slope down which the pump rods and pipes are extended.
Rib. The side of an excavation as distinguished from the end or face.
Rob. To mine coal from the pillars after the breasts are worked out.
Rock tunnel. A tunnel driven through rock strata.
Rolls. In breakers, heavy iron or steel cylinders set with teeth, used for breaking coal.
Roof. The stratum immediately overlying a coal seam. The rock or coal overhead in any excavation.
Room. Synonymous with breast or chamber; used in bituminous mines.
Safety lamp. A lamp that can be carried into inflammable gases without igniting them.
Scraper. A tool used for cleaning out bore holes in blasting.
Screen. Any apparatus used for separating coal into different sizes; usually, the revolving cylinder of wire mesh in a breaker.
Seam. A stratum of coal.
Separator. A machine for picking slate.
Shaft. A vertical entrance into a mine.
Sheave. The wheel in the head-frame that supports the winding rope.
Shift. The time during which a miner or laborer works continuously, alternating with some other similar period.
Shute. A narrow passageway through which coal descends by gravity from the foot of the breast to the gangway; an inclined trough, in a breaker, down which coal slides by gravity.
Single entry. One of the systems by which bituminous mines are entered.
Slack. The dirt from bituminous coal.
Slate picker. A boy who picks slate from coal. A machine used for the same purpose.
Slope. An entrance to a mine driven down through an inclined coal seam. Inside slope: a passage in the mine driven down through the seam, by which to bring coal up from a lower level.
Slope carriage. A platform on wheels on which cars are raised and lowered in steep slopes.
Smut. See [Blossom.]
Split. A branch of a ventilating air current.
Spread. The bottom width of a slope, drift, tunnel, or gangway between the legs of the timbering.
Squeeze. See [Crush.]
Squib. A powder cracker used for igniting the cartridge in blasting.
Steamboat coal. One of the regular sizes of prepared anthracite.
Stopping. A wall built across an entrance or any passage to control the ventilating current.
Stove coal. One of the regular sizes of prepared anthracite.
Strike. The direction of a line drawn horizontally along any stratum.
Stripping. Mining coal by first removing the surface down to the coal bed; open working.
Sump. A basin in mines entered by a slope or shaft, in which the water of the mine is collected to be pumped out.
Swamp. A depression in the seam.
Synclinal. A fold of strata in which the inclination of the sides is from the axis upward.
Tipple. In the bituminous regions, a building in which coal is dumped, screened, and loaded into boats or cars.
Trapper. See [Door boy.]
Traveling way. A passageway for men and mules in or into the mines.
Trip. The number of cars less than enough to constitute a train drawn at one time by any motive power.
Tunnel. An opening into a mine driven horizontally across the measures.
Under-clay. See [Fire clay.]
Underholing. See [Bearing in.]
Upcast. An opening from a mine through which air is taken out.
Vein. Used (improperly) synonymously with seam, bed, or stratum.
Wagon. A mine car.
Waste. Gob; coal dirt.
Water level. An entrance into or passage in a mine, driven with just sufficient grade to carry off water.
White damp. Carbonic oxide.
Wings. See [Keeps.]
Work. To mine.
Working face. A face at which mining is being done.
Workings. The excavations of a mine, taken as a whole; or, more particularly, that portion of the mine in which mining is being done.