The Scranton tribune. [volume] (Scranton, Pa.) 1891-1910, 1896-08-21

occupation. The greatest dangers in the
operation are found where the seam has
an exceptionally strong roof. In sush a
case "suuceze' or general settling Of
the superintendent strata Is probable.
and this can only be prevented by the cree
tion of heavy timber 'shanties" or "cogs'
built OF timber IN log cabin style and the
interior filled with rock, and the breaking
of the roof at intervals by the use of dy-
Mantle. If the roof is not excessively
strong, It breaks of It's own weight inside
of solid pillars. In case of a strong roof
and soft firc-clay floor squeeze has
n tendency TO press the pillars down into
the soft bottom and thus weaken them,
and at the same time materially decrease
the height of the opening, Under such
conditions the pressure of the large mass
OF hanging roof must be relieved quickly
by breaking it.
Good mining consists in recovering the
largest possible percentage of coal in th2
seam 1T the least possible danger ana eN-
pense. Good mining only VIII result in
the production of coal at prices that Will
warrant the profitable working of the
mine. Poor mining, and under this head
comes the injudicious robbing of pillars.
means not only probable danger to the en-
ployes, but the partial if not the total ruin
of the mine. The operator. with n large
amount of capital invested in the opera
tion (sometimes as much as S3o0,OOo to $780,
CCo). Is not the man to encourage the in
judicious robbing of pillars. He wants
the pillars taken out. for they represent
approximately one-half the available coal,
and he wants them taken out systematic
ally and judiciously So they are taken
out, and the coal supply is not wasted.
In some cases. even with the most ap-
proved methods of mining, "squeezes'
occur before the pillars are touched for
final robbing. Such squeezes are gener-
ally due to abnormal conditions existing
in the strata, and they make the future
first work, and final robbing of pillars
more expensive. The usual way of treat
ing such cases Is to leave at regular in
tervcals, one chamber unworked thus
forming binding pillar three times as
large as ordinary. These pillars are nat
urally "robbed' in the final mining. Then
again, the mine may be worked in regular
order. and no special care be necessary
to prevent squeeze" Tho general con-
ditions for several years may be favorable.
Suddenly conditions change through some
purely local cause, entirely unforeseen,
and trouble results. The trouble may be
local to the point where the cause occurs,
but frequently it spreads so as to take in
large portion If not all of the mine and
the pillars originally left. no matter how
large, are found inadequate.
Thus it will be seen that "robbng pill
lars" Is simply one of the legitimate oper-
Gtions In working a coal mine, and an
operation that If not carried out would
brand the operator as a careless, wastetul
business man. He would not be true to
his own interests those of his employees
or the community at large. In his own
| case he would lose the sale of coal that
can be mined cheaper than that taken In
the first working. In the second place he
| would deprive his employees of employ
ment and the chance to mine the coal
| that can be easiest cut by them. In the
| third place he would waste a vast quan-
| tty of Il commodity to which the COM
| munity or consumer has certain rights,
| and which, when produced. adds material
| ly to the comfort of the nation.