164

LAWS OF MARYLAND.

CHAP. 124

as to obtain in cases of emergency a second way for egress
from the workings. No part of said workings shall at any
time be driven more than three hundred feet in advance of
the aforesaid passageways, except entries, airways, or other
narrow work, but should an opening to the surface be pro-
vided from the interior of the mine, the passageways afore-
said may be made and maintained therefrom into the working
part of the mine, and this shall be deemed sufficient compli-
ance with the provisions of this Act relative thereto; said
two passageways shall be separated by pillars of coal or other
strata of sufficient strength and width.

Overcast to
be provided.

Section 209 D of Article 1 and Section 164 C of Article 12.
Where necessary to secure access to the two passageways
required in any slope mine where the coal seam inclines and
has workings on both sides of said slope, there shall be pro-
vided an overcast for the use of persons working therein, the
dimensions of which shall not be less than four feet wide and
tive feet high. Said overcast shall connect the workings on
both sides of said slope, and the intervening strata between
the slope and overcast shall be of sufficient strength and thick-
ness at all points for its purpose ; provided, that if said over-
cast be substantially constructed it shall be deemed sufficient.

Machinery to
be kept in
a safe
condition.

Section 209 E of Article 1 and Section 164D of Article 12.
The machinery used for lowering or raising the employees
into and out of the mines and the stairs used for ingress and
egress shall be kept in a safe condition, and inspected once
each twenty-four hours, by a competent person employed for
the purpose ; and such machinery and method of its inspection
shall be approved by the Mine Inspector.

Number to be
lowered or
hoisted at
any one time.

Section 209 F of Article 1 and Section 164 E of Article 12.
No greater number of persons shall be lowered or hoisted at
any one time than may be permitted by the Mine Inspector,
and notice of the number so allowed to be lowered or hoisted
at any one time shall be kept posted up by the operator or
superintendent in conspicuous places at the top and bottom of
the shaft, and the aforesaid notice shall be signed by the Mine
Inspector.
VENTILATION.

Ventilation.

Section 209 G of Article 1 and Section 164 F of Article 12.
The operator or superintendent of every coal mine, whether
shaft, slope or drift, shall provide and hereafter maintain
ample means of ventilation for the circulation of air through
the main entries, cross entries and all other working places to
an extent that will dilute, carry off and render harmless all
noxious or dangerous gases generated in the mine, affording
not less than one hundred cubic feet per minute for each and