Clearfield Republican. [volume] (Clearfield, Pa.) 1851-1937, 1874-08-12
THE FoRMA 17oN OF COIL.

ffH Il Oft4h a. . O@' ~ NC%ff~f
Coal, then, according to the modern
is merely transmitted
vegetable soil which accumulated, not
under water but under the trees com
posing primHval forests. These forests
stood on areas which were subjected to
repeated changes Of level in relation to
that Of tho ocean. IL must be under
stood that though the ground beneath
us is popularity regarded as the type of
everything steady and immovable, this
earth Of ours is far from deserving the
character for stability with which il is
thus fondly credited absolute rest is
all but unknown to it. 1t happens that
even at the present day there are GER
tain regions, such as those subject to
volcanic disturbances, whose tenden-
cics are always TO move upwards, like
the more aspiring of our youths, while
there are others, such rs the coral re
gions, which are steauny sinking, iiiss
hoscunf0rtunatcyo youths who have failed
in the voyage of life. SO il was in the
olden time. The coal beds appear to
have accumulated on the latter class OF
areas-areas of depression-geograph-
ical regions which bad tendency to
sink below the level of the ocean. Mud
and silt had collected upon such areas
until the deposits thus formed reached
the surface level of the water and then
came what appears TO have been neces-
sary TO the growth of the coal-plants,
namely, bed of peculiar gray mud.
We do not know why that mud came
there, or whence il was derived. That
il was very different from the ordinary
deposits, the sandstones and shales,
which accumulated in the carbonifeI-
Gus ocean, is shown by the physical
properties which it still possesses, and
which they do not possess--properties
which fit il for the purpose TO which il
is now devoted, of being manufactured
into fre-bricks, whence its common
name of firc-clay. That this gray mud
was the soil preferred by the great
majority of the plants constituting The
carboniierous forests is as obvious rs
that the oak wood of Hereiordshire
and the sunny south will not flourish
upon the cold soils of the Lancashire
uplands. Minute spores, representing
tho seeds of the plants which aiterward
became coal, were noatcd 10 this mud
by wind and water and finding there
a suitable soil, they germinated, struck
root, and soon converted the swampy
area into magnificent forest As the
trees grew they shed successive showers
of their microscopic spores, which often
fell in such vast quantities as TO consti-
tute an important contribution to the
accumulating vegetable soil but a long
with them there fell other and more
bulky objects, such as might,b be expect
ed TO accumulate under semi-tropical
forest, thedead leaves, broken branches,
and prostrated stems, alike contributed
a share to the dccaying vegetable mass.
In the tropical regions Of the present
day such accumulations become rapidly
decomposed, and pass away in gaseous
forms but such does not appear to
have been the case in the earboniferous
agc-at least, not in the same degree.
Even in Lancashire, Notwithstanding
all the influences tending to diminish
the bulk of the vegetable mass
such as atmospheric decomposition
chemical changes occurring during
the later process Of naturalization, and
the pressure of super-imposed rocks
prolonged throughout all subsequent
ages, we have coal-seams six or seven
feet in thickness, while they occur in
America, AS forexamplein the oolitic coal
field on the James river, with the sur
prising thickness of between thirty and
forty feet. Such accumulations of
vegetable soil as this thickness of solid
coal represents, almost exceed comprc-
hension, and must indicate enormous
periods Of undisturbed forest life. But
at length change came over the
sylvan scene the land sank--whether
suddenly or slowly we have no means
of saying The numbers of dead fishes
found on the roofs and upper portions
of some Goals seem to indicate a sudden
rush of pure water over the land, fol
lowed by the quick destruction of the
fishes, poisoned by the bituminous
vegetable mud in which they found
themselves entangled. In other cases
the roof of clean blue shale, devoid of
all appearance of either animal or
vegetable remains, and resting immedi-
ntely upon defined surface of pure
coal, is suggestive of a slower submerg
ence, allowing time for the destruction
and obliteration of all traces of grow
ing vegetation upon its surface. The
extent and duration Of the submerged
stage has varied, as also has, in all
probability, the kind of water under
which il sank. Whether the coal
measures are marine or fresh water
dosposit is still an open question, and
answer to which depends partly upon
the nature of certain bivalve shells
! (Anthracosie) found in connection
with many of the Goals. II is allowed
by the advocates of the marine hypoth-
esis, that the ganoid fishes so common
among the carboniferous beds are MS
likely to be fresh water animals as
marine ones--rthe only living ganoids
with which we are acquainted, being
found in rivers and not in the sea but
the weight Of this argument is mate
rally reduced by the fact that in these
pnleozoic ages all the known fishes
were either ganoids OF placoids and no
one doubts for q moment that the great
mass, even of the former. must have
been marine, otherwise we obtain in the
reiuctio dd dbswdtm that there We're
no fishes in many of the ancient seas.
But there remains yet a more conclu-
sive argument in favor Of the marine
hypothesis. Many of the remains of
fishes found both in the lowermost and
in the uppermost coalbeds are those Of
placoids-ancient sharks, often of large
size--and Of many species These
fishes, which are quite as abundant in
the carboniferous rocks as are the gan
oids, were certainly marine animals,
and indicate in an irrofiagable manner
the marine submergenco Of some at
least Of the coal-scams. But the prob.
abilities of the case suggests the conclu-
sion that the nature of the water would
vary at different localities We fire.
quently meet with long narrow areas
ofsandstone plowing theirway through
coal.scams which continue their uni.
form course right and left of these in
terruptions. We may conclude, with
great probability, that such sudden in
terruptions to the continuity of the
vegetable soil represent ancient creeks
or estuarics which ran in among the
forests, and which, doubtless, received
their drainage in the shape of brooks
and rivers. In such cases, submergcnce,