Juniata sentinel and Republican. [volume] (Mifflintown, Juniata County, Pa.) 1873-1955, 1878-06-05

1
under the northern drift. A fne-grained
sandstone, known as the argillacious. ont.
crops west of this, and is ranked by Michi
gan biologists with what is called Marshall
sandstone-it is composed of limestone and
shaies. This group in many other coun-
tries presents coal seams, but in this FORM
alton 1t is perfectly void of seams of coal.
while in its shales perfect specimen. of ma
rine fossils and coal plants are found. This
"knob sandstone" forms the floor of our
coal beds and marks the eastern line of
them. East of them all rocks outcroppine
above the surface dip westward under them
and are geologicslly beneath them. A gray
Eastern sandstone of a course-grained ma.
ture, is noticed on the eastern margin of
the great Indiana coal field, ranging from
~ to 100 feet in thickness. 1t has the
characteristics of what English geologists
denomlnate 's conglomorate or milestone
grit" Spaces exist between the massive
sandstone base and coal, which are occu.
pied By beds Of shale. Occasionally Q
stratum of limestone of an impure nature,
mingled with tire-clay and sandstone-per-
feet casts of sigillarias, calan,ites, ferns and
other beautiful and perfect specimens, which
geologists love 70 study and admire, are
found in these shales, while the limestone
furnishes marine fossils of subcarbonifer-
Gus character. The specific gravity of the
coal OF Indiana is much less than that of
the Appalachian system. A much less
geological disturbance, combined with an
elevation of temperature aud the light pres
sure the fields are subjected to, SAYS Prof.
Brown, would have tendency to diminish
its gravity below that of the bituminous
system, although similarity exists between
the seams of each field, and that in all prob
ability before the upheavai of the " Miami
Axis" and the Carboniferous and Deyonian
strata were divided they were united.
We would like to enlarge on the Eco
nOnlical Geology" of the State, but time
and space will not permit, hence We will
glance casually at her natural facilities,
from geological standpoint.
There are between 8 600 and Z 900 square
miles embraced in the coal fields of Indiana,
all of which is bituminous yet from the
peculiar properties it presents it is divided
into two classes (if you will allow me to
express it In that way) known as s'the free
burning - and the "coking GOALS" The
first class is in blocks and is found at the
base of the coal measures in seams three to
five feet thick. These seams are often sep
arated with a course of shales, fire-clay and
sandstone ranging from twenty to thirty
feet in thickness. A bituminous shale,
named by the miners I" black slate," forms
a roof over them, while a light-colored clay
usually is found underlying them. Perfect
lines OF lamination are presented, caused
by vertical fracture, which indicates that
the formation had been made of successive
layers, resembling hardened asphaltum, and
have no tendency TO harden with heat
Small fragments of charcoal are found, in
which fbers of wood are found almost per-
lcCliN prcScINtu. L MS CiICOdi. Utiug uu-
biruminized, causes very little smoke to be
produced until half consumed, and on COM
bustion resembles that of anthracite, leav-
ing about four per cent. of ashes. Very
little sulphur or phosphorus is found in 1t,
and il has no tendency TO run together into
cakes, hut the blocks maintain their origi-
nal shape until consumed, giving it the
peculiar properties necessary for the smelt-
ing of ores, and almost equal to charcoal in
the production OF pig iron. The upper
Goals are highly bituminous, producing
much smoke, clinkers and ashes. Camel
coal is also found in several counties in the
State. In fact, vast amount Of wealth lies
hidden beneath the soil of Indiana, waiting
for the hand of enterprise to reach down
and lift it up among the developed wealth
of the country. Large and rich varieties of
iron ore are found at the base of the coal
measures, mingled with beds of shales in
the form of nodules several feet in thick
ness. ITO be continued.l
F. p. Fl.