HERBERT R. O'CONOR, GOVERNOR. 1545

"Authorized Person" means any person commissioned by an
official in charge in or at a mine to perform certain prescribed
duties under his authority.

"Communication Device" means any device employed to
transmit intelligence, instructions or warning to persons not
present.

"Crosscut" means a passage driven to connect adjacent
parallel entries or rooms. The term is synonymous with "cut-
through" and between rooms; when driven wide is synonymous
with "break-through".

"Drift" means a horizontal passage-way, or level, or gang-
way, driven from the surface outcrop into the coal bed.

"Duty as applied to a Machine or Device", means the par-
ticular service in which such machine or device is being em-
ployed or intended to be employed.

"Electric Circuit'' means all conductors, including ground
returns, furnishing energy to or receiving energy from electric
apparatus.

"Electric System" means all apparatus and circuits receiv-
ing electric energy or that may receive electric energy from a
common source. Where the source of power is under control
of the mine, such source of power will be so considered as a part
of the electric system. If power is obtained from a central
station not under control of such mine, the phrase shall refer
only to that part of the system which is under control of such
mine.

"Entry" means a passage way in a coal bed which is ap-
proximately level and is used for haulage, traveling way, or
ventilation. In a dipping bed, entries on the strike are known
as "levels" or "gangways" and to the dip are known as
"slopes".

Excavations and Workings: The term "excavations and
workings" includes all the excavated portions of a mine,
whether abandoned or being worked; also all underground
workings and shafts, tunnels, and other ways and openings,
and all such shafts, slopes, tunnels, and other openings in the
course of being sunk or driven, together with roads, appliances,
machinery and material connected with the same below the
surface.

Faces: The term "face" shall mean the advancing breast of
a mine working-place, either of an entry or room.

"Gas" is used in the sense ordinarily employed by miners,
to mean "fire damp", and inflammable gas, chiefly composed of
methane, sometimes accompanied by ethane (C₂H₆) in case
of leakage of natural gas, and explosives when mixed with air
in certain proportions.

"Gaseous Mine" is one in which methane occurs in the mine
atmosphere in such quantities as may become dangerous. If