Evening capital. (Annapolis, Md.) 1884-1910, 1885-04-08
THE FORMATION OF COAL
How the Earth's Black Dia-
nonds were Created.
Composed Of Many Successive Layers Of
Vegetable Natter

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Templln to the Kansas City mo. Re-
OtesO az Science. occurs this passage:
There would be long period when
the land surface was above the water:
immense forests Of vegetation would
flourish until huge layer OF It was
accumulated, when by some convul-
sion Of the crust Of the earth, or by
gentle-perhaps to human eyes it
would have been imperceptible sub
Sidence, It would be depressed below
the waves and receive. either from
fuviatile or marine sediment, layer
Of earthly material. covering the layer
Of organic matter to depth Of many
feet A reversal Of the process By
which the land was depressed again
elevates the surface above the waters
and again a layer of vegetation would
be produced, to be in turn buried as
the former was. And thus these alter
nate elevations and depresslons con-
tinued till, as we have seen in some
cases. hundred or more beds of vege-
table matter have successfully grown
and been buried. The pressure and
beat to which this organic matter was
subjected after such burial eliminated
the greater portion Of the volatile
gases. and converted it into coal. The
time necessary for the accumulation Of
all the organic matter contained in all
these strata, and in the subsistence
and elevation. and for the deposition
Of the sedimentary materials compos-
Ing the rocky strata interposed between
these coal seams, cannot be estimated
--even approximately. But we are
sure it must have far exceeded all
conceptions of duration that we can
form from our knowledge of human
history. We have no data on which
to base any estimate Of the rate of the
accumulation of sedimentary matter;
except the present rate Of sedimentary
deposition at the mouths Of rivers.
The present average amount OF sedi-
ment carried down by the Mississippi
amounts to enough to cover one mile
square to depth Of 26S feet annually,
or about one cubic mile in twenty
years. At this rate it is estimated
that it would have required about
100000 years to haye carried down
and deposited the amount Of materials
that originally composed the rocks of
the coal measures in the coal fields
noticed above.
The time occupied in the growth Of
the vegetation that formed the various
beds Of coal may be more nearly APP
proximated. FIVE assume the amount
Of vegetation growing on one acre at
1900 pounds. this would give in 100
years 100 tons. This compressed into
coal and spread over an acre Of ground
would give thickness Of one eighth
Of an inch Of coal ii i century, or I0 900
years would be consumed il producing
one foot OF coal This would require,
to produce $50 feet, As found ii some
regions, no less than 100000 years.
But probably the growth Of coal
plants. with the very high temperature
and heavy atmosphere. laden as it was
with carbonic acid that prevailed dur
ing the coal age. would produce &
much larger growth Of vegetation
than we have estimated. and the time
gould be accordingly diminished. But
aoakinr due allowance for this. there is
20 question but the time required FOR
ne growth Of al this vegetable mat
ter che frequent subsidences and ele-
zsions and the accumulation Of the
elementary matter composing The
Dcks Of this formation must have re-
.mirea hundreds 81 thousands il not
n'''ions 0f years
NNe4-aHs4s
a pnppys joke is not very funny
bu1 there j. something wagish about