The Wheeling daily register. [volume] (Wheeling, W. Va.) 1864-1878, 1874-09-02
The Possibilities. orCOaI Mining

The prospective exhaustion of British
coal mines has induced Il number OF
scientific Englishmen to investigate the
practicability of continuance OF mining
operations to a great distance below the
surface of the earth. Some of the opln-
ions expressed are interesting to at least
portion of the citizens of State so
actively engaged in coal mining ms West
Virginia. As an illustration Of what
has already been done, the statement Is
made that coal is now mined IN certain
pits in Belgium at depth OF four thou
sands feet, and from this fact the con-
cluson is drawn that coal mining could
be proftlbly carried on in Great Britain
ut the same or even greater d"pth
One of the most serious obstacles to be-
encountered is the high temperature
prevailing at very great depth. but 1t
Is alleged that the ratio of increase dlt-
! fers in various localities, and also
diminishes ms distance lengthenS. For
instance, in mine shafts in Cornwall
! it was observed that son the first lOo
I fathoms in depth below the plane OF
! inyariablc temperturc, the increment OF
. tcmpcrature was about one drgrr"
Fahrenheit for each fifty feet in drpth;
! that for the next 100 fathomS it was ut
! the rate of one degree Fahrenheit for
seventy feet, and for the next, or third
( 100 fathomS. at the rate of one degree
Fahrenheit for eighty-tivc feet in depth.
! The increase of Temperature with depth
in metallic mines of Cornwall thus ap-
pears to be a decreasing series, and the
temperature to be reached at some much
greater depth might prove much below
that calculated on the common asSump-
ton that the rate of increment is con-
slant, and amounts to one degree
Fahrenheit for each fifty feet descent. W
The highest temperature Supposed to be-
compatible with continuous healthy
work in coal mining by white labore's
i about eighty degrees Fahrenheit, and
it is believed that by known methods
of ventilation the temperature of work
ing places may be kept at this point
even when the surrounding rocks or
walls are at 100 degrees, or possibly
even more.
Another question considered Is tn"
limit in depth at which coal can exist,
and on this point the conclusions reach
ed have an important bearing on the
origin of petroleum. 1t Is SAID that
experimental facts prove that lat II tenn
pcraturc far below rednc>S, or between
700 degrees and 800 degrees Fahrenheit,
coal is rapidly dccomposed, not ~ in the
rrd-hot gas retort, mainly into intiam-
mablc gases and coke, but into various
solid and liquid hydrocarbons with little
GAS and little coke At much lower
temperatures the same sort of dccomp"sl-
ton also goes ON, but less rapidly, and
these assumptions indicate that at II
maximum depth of 4O,OOOtc"t, coal a.
such cannot exist, and it Is not probable
that-even aided by the superintendent
pressure and in quite dry ScamS-it can
have permanent existence at even halt
that depth. At such great depth rs be-
tween four and eight miles or more,
coal. Mt the temperatures assumed,
would probably be replaced by hydrocar-
bons like native naphtha or petroleum,
1t is indeed, highly probable that such
a process of natural diS:illatiOn, which
has occupied ages in completion, has been
the origin of the mineral oil wells OF the
United States, of the great deposits OF
ozokeritc in the Ignite formations OF
Germany, and ofmany fossil hydr"car-
hons known to science, 1t Is supposed
that some of the British coal fields extend
beneath the North sea for a great dis
lance, but that at depths exceeding four
or five miles it is not coal, but petroleum
that probably fills the seam.
The area of the bituminous coal dis
tricts of the United States Is so immense
that no conceivable increase III the de-
mands made upon them will ever
ncccssitate general resort to very deer
, workings; but the supply ofanthrnrit'
is sufficiently limited to indicate that the
vast interests connected with lis cNtrar'
ton from the earth, transportation /.
: market and consumption Will at some
! future period be deeply interested IN the
problems which are new attracting
serious attention in England.