The herald., 1922-09-21

prepared BY the National Geographic 60.

"repsred oy the National Geographic s
ciety. Washington. d. c.
Coal Is one OF the vital factors |
modern civilization that is taken IL
granted. 1t is only when the priceless
black stream that flows to our cite
and factories threatens to dry I'D tina
the average person gives thought I
the Importance, magnitude and con
piexity of the coal industry.
The first thing that impresses ON
who studies the coal situation in Amer
lea Is the well-nigh inconceivahle pro
portions OF the nations demands TO
Iuei. The highest point in coal produc
tion was reached In 1918. the last yea,
or the World war. when slightly more
than 6OO,OOO.OOO tons were mined, Bu,
In the year Immediately preceding and
IN ls2O the production was little shor,
OF that amount. So huge Is this figure
that 1t were almost as futile to use
tons as units rs to measure the dis
lance around the earth In inches.
About the only way in which one can
visualize this demand is TO build a
mental bin capable of holding enough
TO meet the national need. If this bin
were made with each of its four sides
measuring a thousand feet, II would
have to be more than 2I,OOO feet high
almost twice as high as Pixies Peak.
Or, II the fuel were put into a coal
pile OF normal slope, with a base of
~ feet, that pile would have TO be
nearly $4,000 miles long-more than
three times around the earth.
A visit to modern colliery In the
anthracite region is an Impressive ex.
perience. Depending on its size and
the labor available. il will bring from
one to two full trainloads of coal up
OUT or the bowels Of the earth every
day, put the coal through the breaker.
where the sheep of fuel are separated
from the goats of slate and culm and
ioao II into the cars ready for market.
Colliery In Anthracite Region.
We shall be safe even if we go down
thousand feet into the earth and
roam about In an underground planta-
uon whose area may be judged by the |
fact that there are So miles of railroad
track in 1t.
There are some things on top of the
ground that will be even more inter. |
esting to us when we 60 below-par-
ucularly the hOisting engine and the
ventilating fan, for without the one we
would not be able to ride back to day.
light, and without the other we would
stand chance of being "gassed" in
times Of peace.
The giant fans fly around with n
nm speed OF mile q minute, two of
them, with third in reserve for emer.
sencies. Ii 1t were not for those fans
the air In the mine would become SO
laden with gas and dust that IL II did
not explode and transform the whole
mine into charnel house. It would
develop choke-damp and suffocate Ms
Every mine has two shafts-tbe
hosting shaft and the air shaft. Tn
order to keep the air in the mine free
enough from gas TO permit miners TO
work In safety, enormous Quantities
or fresh air must be sent down the
'ne shaft and corresponding quantities
sas-iaden, drawn out of the other.
1t may very well he imagined that a {
nine with enough tunneling to call |
or 80 miles of railroad track needs
great deal Of air, and that this air. q
o reach every part, must cross its own q
oath many times. Just as man. cover. a
ng all four sides of every block in n q
aSy. would have to cross his own a
3. In the mines this is accom-. O
"a like railroad crossing by I
ne instead Of at gratie. When n h
Tossing point is reached. there &c a q
unnel opened up through the solid d
ock above the roof of the mine and
through this the air rushes at right n
ngles to its former direction. "
To get the air properly distributed II
10 necessary to make splits, so that I
ne current can be divided and sent In. II
Inherent sections Of the mine. These c,
r splits are doors which permit only h
III OF the air coming their way TO
lss. The remainder must find some W
her way through. m
We step on the cage" or lift. the ct
me superintendent presses button. u,
d the hosting engineer is notified tn
1t we are ready to go down. Sud- tn
My the cage seems to drop; then II In
ms to stop, and the walls of the In,