The Salt Lake herald. [volume] (Salt Lake City [Utah]) 1870-1909, 1900-05-02
TIE SALT LAKE HERALDs WEDNESDAYS MAY 2 1900 =

shock. Among them was the master
mechanic Of the mine
The workings of a coal mine. its
many passages, rooms. pillars, air pas
sageS. etc, are almost a sealed book
to the average layman- AS a rule,
coal mines are mitch alike. and are
worked on the same general plan
Starting from the entrance to the coal
mine q wide passage or tunnel runs
down INTO the ground at a greater or
less slope. Branching off from this
on each side are various passages or
entries as they are called. in old mines
there may Ee from twenty TO thirty
Of these entries on either side Of the
tunnel.
OF these entries are the rooms in
which generally two men work at a
time These are worked in the form
OF a passage toward the entrance of the
mine. As the miners proceed they
exeavs ,e in the form of q. fan. These
rooms are run into the solid wall of
COAL say. about $50 feet The next
entry viii be 400 feet down. thus leav-
ing what is called a pillar Of, say, l50
feet. AS each new room is developed
and the wall between it and the next
room is made thinner an air passage
is made between il and the room near
er the mouth of the entry.
The idea is to work out the coal as
methodically as possible along these
lines. The air is forced through the
mine by an immense fan on something
after the following plan: At the outer
edge of the first TRAVERSE passage or
entry is a gate This is practically
air tight, and IS opened and closed for
the passage Of coal cars or boxes, as
the miners cali them. by a boy. This
is the sole duty of the boy. He does
nothing else all day long, and makes,
as a rule, dollar and half thereby.
Air Passage Cut Through.
The air passage is cut through from
the tunnel on the outside of this door,
or nearer the entrance to the mine
and through it the cir enters the first
room. From this it filters through the
air passage that has been bored
through the solid wall of coal into the
next room, and so on till it gets to the
end OF the rooms running OFF the en-
try. Then it comes back along the
entry toward the tunnel, but here it is
met by another closed door, and con-
sequently passes through another air
passage cut through the wall or pillar
on the lower side of the entry to the
next series Of rooms.
Through these it passes in the same
fashion till it arrives at the last set or
the end of the tunnel Here is an
other air tight door and the air passes
around the back or lower end Of it
and begins its upward passage in the
sans way as it was forced down. till
it arrives at the fan at the outward
end Of the passage. This huge fan is
sucking the air out of the mine at a
tremendous pressure, and as il passes
out Of course more and fresh air must
come in to fiji up the partial vacuum
created.
When the mine has been worked in
this way on the down grade to the end
Of the claim, or as far as it is cOnsid-
cred profitable, the aim is to work
back TO the entrance, mining out the
pillars. The pressure Of the earth from
above squeezes out the coal so that no
blasting has TO be done on the back
ward working. This is the theory Of
the working Of a mine to get all the
coal out of it. but not one in a hun
dred is worked successfully to a finish