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The Indiana field, in which we are now holding
session, and of which we are at the geographical,
governmental and geological center, is not very
generally known and appreciated. It is remarkable,
that owing to adverse conditions, a county
so wealthy in carboniferous content as Indiana
should have remained for years wholly, or almost
wholly, unknown to the mining industry.
The field lies at the northern edge of the Pittsburgh
measures; there is, however, but little
Pittsburgh coal in Indiana and, of course, still
less Redstone or Sewickley, these last two beingvalueless
in this field, nor are any more recent
measures represented.
THE COAL TRADE BULLETIN. 35
GEOLOGY OF INDIANA COUNTY 1
But the lower measures are near or below the
water level throughout the county. This makes
their area less broken and very nearly coextensive
with the district. To-day no better word
than this could be spoken regarding a field, unless
one would speak of quality or possibly of absence
of folding ir faulting, but in the early days, when
pumping was expensive and more rare, a field that
manifested itself only at its anticlinals and that
gave small show for gravity drainage, had to wait
on fields which dipped conveniently at all points,
toward an extended crop line. When diamond
drills were unknown, a field that revealed itself
but rarely was subject to justifiable suspicion, for
PROOF WAS WANTING
that the field was continuous under heavy cover.
A field like that which we are considering, which
under conditions then obtaining, could only be
mined locally, did not suggest the construction of
railroads and the feasible locations, as far as the
geological and geographical conditions constitute
feasibility, were left untouched or barely scratched
for lack of transporting facilities.
It will be observed that nearly all the valleys
of this field open towards the Allegheny river
waterways and consequently they were face to
face from the first with the competition of Pittsburgh
coal at its best. It could not be expected
that Indiana would come to its own, until large
plants were the rule and not the exception, until
strong "coal barons" could be found to make the
necessary investment, and until it became customary
to build roads like the Buffalo, Rochester &
Pittsburgh and Buffalo & Susquehanna railroads,
for the express purpose of obtaining a coal tonnage
to be sold away from Pittsburgh. Indiana
is a big man's field both by character and practice.
It does not fit the small purse. But if
you put a mine in Indiana west of Chestnut ridge,
•Paper read before the Summer Meeting of the Coal Mining
Institute of America. June 28 and 29. 1911.
By R. Dawson Norris Hall, Du Bois. Pa.
even one of drift workings, you can direct your
headings North, South, East and West. If you
are justified in expending $300,000 in a plant on
the bank of a river, where
THE COAL AVAILABLE
within the radius of three miles is represented
by a semi-circle enclosing 9,049 acres, you are
justified in expending $600,000—twice as much—
where the plant is penned in by the hills and the
coal available within the same radius, is represented
by a full circular disk of 18,098 acres.
The conditions in such a case are favorable for
a mammoth construction and large output especially,
seeing that not only in primary development
but in all later stages, the area is right at hand,
not divided by ravines, which not only reduce tonnage
but involve manifold expense.
A mine that just touches water level, that gives
the right, left, forward and backward development
of a shaft, without its disadvantages is an ideal
mine. It endures longer than any other and it
starts development at mushroom rapidity.
It has been suggested that we term coal, sur
rounded by crops on every side, a coal island or
carbon-insula. Similarly the coal of the Indiana
field may be comparably termed a carbo-continent.
The lower series XIII, or Allegheny formation,
is an area of coal, broken not so much by large
gulfs of erosion from its outer margins but by
erosions within these margins, forming what we
may compare to lakes rather than to arms of a
sea and the areas covered by the "coal-less lakes"
are small and narrow and render the
APPROACH TO THE MAIN BODY
the more available. The Chestnut ridge erosion
is, however, somewhat more extensive. The croppings
of the Indiana field are clearly assets and
not debits. Were it not for them, Indiana county
might still pride itself solely on being one of the
premier farming counties of the state, but it
would suffer grievously from the lack of a home
market and of adequate transportation to more
distant marts
I have said enough to convince you, I trust,
tnat Indiana is the place for large plants and to
show you that hard-headed reason is back of this
method of development, not merely corporation
pride or reckless extravagance.
A map of Indiana county, with the various summit
and depression lines of the folding, and with
the contours of the upper Freeport seam showing
the elevation of that seam above sea level, would
indicate what I mean.
These summit and depression lines are quite usually
termed "axes" though a better name is needed