ART 1. ] MANUFACTURERS AND MINERS. 73

or agent of each mine shall employ a competent and practical
inside overseer, whose duty it shall be to keep a careful watch
over all the ventilating apparatus that may be placed in said
mine, as well as all the air-ways, all the travelling-ways, and all
the timberings, and to see that all loose coal and rocks overhead
are carefully secured against falling upon any of the miners
engaged at work therein, as they advance in their excavations;
and it shall be the duty of the inside overseer so employed, to
take charge of and keep a careful watch over all things con-
nected with and appertaining to the safety of the men at work in
the mine, and to report to the owner, lessee or agent of said mine
"when and where anything under his charge is unfit for mining
purposes; and it shall also be the duty of the inside overseer so
employed, to take charge of and pay strict attention to all the air
doors used in the ventilation of said mines; and all air doors
used in the ventilation of said mines shall be suspended in such a
manner that they will close of their own accord.

1878, ch. 157.

204. The owner, lessee or agent of every mine in operation
in the said counties of Allegany and Garrett shall furnish at
his own expense all props and all the requisite timber that may
be used in the working of said mines; and as the miners em-
ployed at work therein proceed with the working of their excava-
tions, it shall be the duty of the owner, lessee or agent of said
mines to furnish a sufficient quantity of timber at the place
where the miners are at work; and whenever the said workmen

engaged in the said excavation shall deem it safe and proper to
have any of the props or timbers removed from said excavations,
it shall be the duty of the person so employed by the

owner, lessee or agent, to remove the said props and timbers to
whatever point or place the workmen engaged therein may
require, but no props or timber whatever shall be removed when
such removal may endanger the lives of any of the workmen
engaged therein.

Ibid.

205. Whenever any impure air or gases are known to exist
in any of the mines in the said counties of Allegany and Garrett,
which are likely to endanger the lives of the miners employed