The star. (Reynoldsville, Pa.) 1892-1946, 1892-05-18
THE SUN WILL CEASE.
A TIME MUST COME WHEN HEAT
FROM THE SUN MUST CEASE.

Measuring Mnn's Days ca Come-The
Great Orb nj Light and f.ife Stay Last
100000 Years, hut Not io.ooo.ooo.
Tho secret Of tho ssu's Heat.
II seems TO be worth while TO collect
together what may be said on the sub
iect of the duration of life ON the globe
Il Is noteworthy fact that the posi-
bility Of the continued existence OF the
human race depends fundamentally
upon the question Of heat n heat, or
what Is equivalent TO heat, does not
last, then man cannot last, either. There
is no shirking this plain truism.
OF course IL is obvious that the avail
able heat generally comes from the sun.
so far IA the coal goes, we have already
observed that as it is limited to quantity
1t can afford no perennial supply.
Doubtless there is in the earth some
quantity of other materials capable Of
oxidation or Of undergoing other chemi-
cal change, in the course of which and
as an incident Of such change heat is
evolved Tho amount of heat that can
possibly arise from such sources is
strictly limited. There Is in the entire
earth Just certain number Of units Of
heat possible from such combinations,
but after the combination has been ef
fected there cannot he any more heat
from this source.
Then rs to the internal heat of the
earth due 10 the incandescent state Of
its interior Here there is no doubt
large store of energy. but still II is of
limited quantity, and 1t is also on the
wane. This heat is occasionally copious-
ly liberated by volcanoes, but ordinarily
the transit of heat from the interior TO
the surface and its discharge from
thence by radiation is n slow process.
II is, however, sufficient for our present
purpose to observe that slow though the
escape may be, ii is necessarily going
on. There is only definite number of
units of heat contained in the interior of
the earth mt this moment and as they
are gradually diminishing, and as there
is no source from whence the loss can
be replenished, there is here no supply
of warmth that can be relied on perma-
nently.
It goes without saying that the well
fare of the human race is necessarily
connected with the continuance of the
suns beneficent action. If the sun ever
ceases to shine. then must it be certain
that there is n term beyond which hui
man existence, or indeed organic ex-
istence of any type whatever, cannot
any longer endure on earth.
But we have grounds for knowing as
o certainty that the sun cannot escape
from the destiny that sooner or later
overtakes the spendthrift. In his inter
esting studies of this subject Professor
Langley gives striking illustration Of
the rate at which the solar heat is being
squandered at this moment. He remarks
that the great coal fields of Pennsylvania
contain enough Of the precious mineral
TO supply the wants of the United States
for 1000 years. If all that tremendous
accumulation of fuel were to be extract
ed and burned in one vast conflagration
the total quantity Of heat that would be
produced would no doubt be stupendous,
and yet, says this authority who has
taught us so much about the sun, all the
heat developed by that terrific coal fire
would not be equal to that which the
sun pours forth in the thousandth part
of each single second.
When we reflect that this expenditure
Of heat has been going on not alone for
the centuries during which the earth
has been tho abode of man, but also for
those periods which we cannot estimate
except by saying that they are doubtless
millions Of years during which there
has been life on the globe. then indeed
we begin to comprehend how vast must
have been the capital Of heat with which
the sun started on its career,
And yet we feel certain that the inces.
SAINT radiation from the sun must be
producing profound effect ON its stores
of energy. The only way of reconciling
this with the total absence of evidence
Of the expected changes is to be found
In the supposition that such is the
mighty mass Of the sun, such the pro.
digious supply Of heat, or what is equiv.
alent to heat that it contains, that the
grand Transformation through which II
is passing proceeds at rate 80 slow that
during the ages accessible to our obser.
vations the results achieved have been
imperceptible. But the energy Of the
system is as surely declining as the en-.
ergy Of the clock declines as the weigh,
runs down.
1t seems that the sun has already dis
sipated about four-ffths of the energy
with which it may have originally beer
endowed. At all events, it seems that
radiating energy at its present rate, the
sun may hold out for 1900, 900 years, OF
for 5000, 900 years, but not for 10000,
b 900 years. Here, then, we discern IL
the remote future limit to the dura
tion of life on this globe. We have seer
that it does not seem possible for any
other source of heat to be available fol
replenishing the waning stores of tn,
iuminary. 1t may be that the heat wa
originally impaired to the sun as tn,
result Of some great collision between
two bodies which were both dark befor,
the collision took place, so that, in fact
the two dark masses coalesced into ,
cd nIxl he Ill