Indiana State sentinel. (Indianapolis, Ind.) 1861-1865, 1861-04-24

not only in the strata different places and diff
ferent geological horizons, but even in pieces ia
ken from the same bank. According to the spe
cies and nature of the plants which have formed
it. it contains more or less of bitumen, and also
more or less of carbon According to circum
stances which accompanied and followed its form
alton, it is mixed with more orless ofearthy mat
ter, and impregnated with variable quantity of
mineral compounds, especially sulphur and iron.
According to the position of the bed, and the ma
ture of the everything strata il is more or less ex-
posed to atmospheric influence, to percolation by
water, &c, is thus more or less Oxidated, has va
rious degrees of capacity or compactness, and its
chemical elements, combining in different ways,
produces variety of compounds. All these in
huences, and MANY Others have acted, and are
still acting, in different way different parts of
the coal strata and for this reason, it is seldom
that we find the coal a homogeneous matter, to
any great extent, even Of the same bank.
To fully understand the causes of this diversity
in the composition of coal bed it suihces to
examine the formation of peat bog or the ap
pearance and vegetation of its surface, together
with the perpendicular section of bank where
it is cut for obtaining the peat. On the surface
of the bog, at any time of its growth, We find
some parts overgrOwn with kind of pne,f from
whose branches and leaves, pitch constantly ex-
udes and drops in such abundance that it encrusts
the ground, sometimes few inches in thickness.
Near by, the surface is occupied by small and
very shallow ponds of various forms, without
any vegetation whatever. BY the evaporation
and percolation of these waters, (only few
inches deep,) these shallow ponds become en-
tirely dry IN the summer months, and the surface
of the peat thus exposed to atmospheric influence
is decomposed and changed into thin LAYER of
mud Near BY again, the mOssSes have over
run the ground, covering it entirely with a
growth so dense and luxurant that in passing
-,t1 ,,,l
humid mass OF this peculiar vegetation Here
and there tufts of rushes and sedses penetrate
the moss, forming hard woody knots where the
foot can rest securely. At a few PAGES distance.
the ground suddenly becomes compact by the
growth OF small species OF the heath family, the
cranberry, tie cOwbeny, the bOg-dilberry, &c.
At some othor places, the ground is covered by
hchens and becomes very hard; at others still, 1t
is overgrown with grasses, sedges and bushes.
Indeed, there is not. on the whole surface of
peIt bog, space of twenty square feet which
presents the same vegetation and the same ap
peaIance.
In examining the perpendicular section of a
bank OF peat, where it has been cut for fuel, the
same extraordinary variety is observable in its
composition. To SOFT spongious layers of
scarcely decomposed mosses. from one to twelve
inches thick or more succeed, in descending or
der, thin layers OF muddy, black, hardened mat
ter; then a compact thin stratum of interviewer
roOtlets and stemlets of small woody plants; then
branches of half-decomposed grass, everything
trunks and roots of PROSTATE (rarey standing)
pines or tamaracks generally imbedded in black
bituminous, compact peat; and thus, by continu-
and alternative changes to the base of the
bank. In following the same section in horizon
tai direction, or from point to another of the
bank, on the same level, we find just the same
variety of appearances observed upon the
surface. The layers extend in kind of homo
geneousness for few feet, and are then succeed
ed by others of another compound. Thus ithap-
pens that two pieces of peat taken from the same
bank and subjected to chemical analyses, rarely
show the same proportion in their chemical CON-
pounds.
of appearances those observed in the peat.
The top coal, the middle coal, the bottom coal,
terms generally employed by the miners to in
dcate different quality of matter in the same
bank And every miner knows that in following
an entry or gangway, the coal sometimes, either
at once or by gradual transitions, becomes
of better or of poorer quality. And so the
best places of bank are carefully looked for
and the poorest ones thrown away with the rub
bish.
From this we can easily understand how re-
peated analyses of the same coal bank generally
show differences of some kind, sometimes great
differences indeed. When the Breckinridge coal
was first examined it was pronounced free from
sulphur, and leaving scarcely one per cent. OF
ashes. The average of four analyses, reported
page III of the first volume of the Kentucky
geological report, gives 96 per cent. of ashes,
62.40 of volatile combustible matter. In vol. 2,
pages 2ll and 2l2 of the same geological report,
repe Ited analyses of DR.. Peter Indicate 81 40
per cent. of volatile combustible matter and ~ sc
per cent. of ashes. On examing different por
tons of a large piece of this coal (about five
Il Il
the same chemist found considerable difference
in the proportion of the compounds. For exam
pie the proportion of the volatile matter was
found to vary from 50 10 per cent. to IL 20; o
coke from $3.50 to 44.30, and of ashes from tC
1880 per cent.
This can not in any way discredit the Value o.
chemical analyses of the coal, but only show,
how careful one must be in selecting specimen:
for the laboratory. Its evident that the success
depends as much on the quality of the matter al
on the thickness of the bank. There is eertainl,
no country where chemists often calleC
upon to give an opinion about the value of Goa
bells, and where chemical examinations have beer
pursued with more conscientious care, and none
also where many fallacious and deceptive
valuations ON the quality of coal banks have beel
! published. Many proprietors and companies hav
sustained great losses and some have failed Ell
| tirey from this cause alone; because Their Goa
was in Tor as il is when delivered to the market
far inferior to what the chemical analyses had le
them to expect OF course propretors and miner
are ali interested in giving good name to thei
coal, and are all bOasting of having the best Goa
/ in the country When they send specimens o
coal for examination to a laboratory, they pic
up always the best pieces. Ii in the bank, ther
Is. occasionally, thin layer of pure coal, ire
from sui ulphuret, shlles and charcoal OF cours
it is this part which is selected for the chemist
shocing the acreage quality OF the newly opene
coal bunk. 1t is voluntary cheat, which heir
nothing and deceves badly the proprctors them
selves. For, If the true value OF coIl was faTl
ascertained, it would be elsy TO know for wins
purpose it may be used to the best advantage
would be thus possible to find a market even fC
an inferior quality, and measures would be take
accordingly. But when coal has been prC
claimed from chemical evidence. as being of tll
very best quality for every purpose. proprietor
companies send j. indiscriminately to ever
market. m Ike bargains with gas works. iro
furnaces, steamboat landings coal merchants, etc
and incur large outlay for their working. And
after while the coal is pronounced unfit for al
of the purposes for which it is used, il loses
once its good name and is declared good Fl
nothing whatever. Thus the works are stOppe
the money is lost. and coal. valuable. perh1p
for purpose different from those to which it h.
been applied, is abandoned as worthless
How, then, can the average value of a co
bank be fairly estimated BY ali the metho'
commonly employed, by chemical analyses, tria
/ in the FORGE in the furnace. in the CRATE, 81
: any of these tests may prove satisfactory, if on
samples for examination are fairly selected, 4
cording to the following very simple rules:
lst Specimens cannot be taken from the OF
crop of a coal bank, or from its immediate
cinity. When the roof of coal bed is not
solid stone, entry of at least twenty feet is n
= cessary to find the coal in its normal state, and
: judge It's average quality.
" 2nd. Samples of coal for every kind of expe
iment ought to be selected from various places
, = gangway, and taken from different places
! represent the whole thickness of the bank.
even there are within the bank streams of 81
- phuret or layers of shaes too thin to be cas-
!, ceansed or separated by the miner, piece: of {
- coal containing these matters ought to go wi
!; the specimens for examination
Sd. Generally the miners know the coal W
enough from the look. But their opinion is oft
! influenced by personal interest, and consequent
= unreliable Ii an expert is called to examine
= coal, he can make his conclusions in far bet