TECHNICAL TERMS.

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Frame Dams. —Beams of timber wedgedtogether for the purpose of draining water.

Firing Point. —When the inflammable gasis sufficiently mixed with atmospheric air asto explode on the application of a lightedcandle.

Fire-line. —A staff with a candle at the end,to fire the carburetted hydrogen on the roofof a mine.

Falls are breakings down of the roof of amine, and frequently injure the workmen verymuch. In many cases they obstruct the venti-lating medium.

Headways. —A passage single or double,driven in the longitudinal direction of the coal,and running parallel to another. The twodrifts between the shafts are called the doubleor winning headways.

jHewers. —Men employed to cut the coalfrom the stratum.

Jenkins are narrow passages cut throughthe middle of the pillars for the purpose ofgetting the coal left in the first working.

Keeper. —An inspector of the hewers, &e.

Low. —Small candles which the miners use,and which are fixed in pieces of clay in orderto hold between his fingers, or stick upon thecoal.