The Mount Holly news. [volume] (Mount Holly, Burlington Co., N.J.) 1891-1942, 1906-06-26
YEARS OF THE EARTH

YEARS OF THE EARTH
THIS WORLD OF OURS COUNTS THEM
BY THE MILLIONS.
Famous Scientists Have Endeav-
ored to Figure Out the Age of the
Planet Upon Which We Live.
The time has admittedly gone by for
attempting to reconcile the facts of
nature" to use a recognized phrase,
with the chronology of the Bible, which
makes the age of the world rather less
than 1900 years.
Indeed, In the Egyptian rooms at the
British museum the visitor can see for
himself objects which go back to an
authenticated period long antecedent
to 1000 years B. c., and great is the
wonder produced on the minds of those
who first make their acquaintance.
In that same department, among the
mummies, there is what is In many re-
spects the most striking of the exhibits
In the department-the body of a man
who belongs to the stone age 1t lies
In an accurate representation of the
peculiarly shaped grave in which 1t
was found, and 1t has been In conse-
Quence somewhat irreverently nick
named by the habitues of the museum
''the man In the pie dish"
The particular interest in that corpse,
which men, women and even children
look upon without the least thought or
suggestion of the fear or horror usual
ly inseparable from death, Is that 1t liz
unQuestionably the oldest exhibit In
the museum, and scientists have been
rather struck by the fact that the au-
thorities of the great institution In
Great Russell street have not, SO 10
say, taken the bull by the horns, boldly
labeled that exhibit as dating from
10000 B. G. Thus with one single
stroke of the pen Bishop Usher's Bib
dcal chronology is multiplied by about
nine, and 1t may be that an even high
er number would be required to satisfy
the requirements of the age of that
particular specimen.
How long has the earth been a planet
capable of supporting not only human,
but all forms of lifef
In an address Lord Kelvin once de
fvered on the subject he gathered to
gether the opinions of various scientific
men which cannot but be of interest
to every thinking being. Darwin, in
his "Origin of Species" stated that,
sin all probability a far longer period
than 800,O000O0 years has elapsed;"
while later on, In the same book, he
wrote: HE who can read Sir Charles
Lyelrs grand work on the Principles
Of Geology which the future historian
win recognize as having produced q
revolution In natural science, yet does
not admit how incomprehensibly vast
have been the last periods of time, may
at once close this volume"
Lord Kelvin himself-then Professor
William Thomson-later made an at.
tempt to calculate the length of time
during which the sun has been burning
at its present rate, and In that connec.
ton he wrote: at seems on the whole
most probable that the sun has not
Illuminated the earth for 100,00O,OO0
years and almost certain that it has
not done so for 5OO,OOO.OOO years. As
for the future we may say with equal
certainty that the inhabitants Of the
earth cannot continue to enjoy the
light and heat essential to their life for
many million years longer unless new
sources, now unknown to us, are pre-
pared in the great storehouse of crea-
ton"
1t is a remarkable evidence of the
acute perception Of Lord Kelvin's
mind, as of the rare provision of his
intellect, that the last words unless
new sources, now unknown to us, are
prepared In the great storehouse OF
creation"-should have been added to
that remarkable sentence.
AS an example of the very extraor-
binary range Of time given to the age
Of the earth, consider the following
statement from Professor Jukes' "Stu-
dents Manual of Geology" He wrote
''Mr. Darwin estimates the time re
Quired for the denudation of the rocks
Of the weald of Kent, or the erosion of
space between the ranges of chalk hills |
known as the north and south downs, |
at 3OO,OO0,O00 years. 1t may be posi- |
BILE. perhaps, that the estimate is a
hundred times too great, and that the |
real time elapsed did not exceed 3,0OO,- |
600 years; but, on the other hand, it is
just as likely that the time which |
actually elapsed since the first com
mencement of the erosion till it was
nearly as complete as 1t now is was
really a hundred times greater than
his estimate, or 3OO,OOO,0OO years."
Professor Phillips in a lecture at the |
University of Cambridge considered
the rate of erosion between the ranges |
OF the north and south downs to be |
rather one inch year than Darwin's
estimate of one inch In a hundred |
years, so that on mere geological |
grounds he reduced the time to about |
a hundredth. Calculating, however,
the actual thickness of all the known |
geological strata of the earth he came
to the conclusion that life on the earth's
surface may probably date back to be
tween 3S.OO0,000 and 100000 years
Professor Sollas of Oxford, working
on new principles applied to the strait.
fed rocks, reduced this time very con
siderably, for he wrote, $50 far as
can at present see, the lapse of time
since the beginning of the Cambrian
system is probably less than 17,0O0, 600
years, even when computed on an as
sumption uniformity, which to me
seems contradicted by the most salient
facts of geology"
What are the data. it will naturally
be asked, on which calculations of this
magnitude are made? Among the
most important are the consideration |
of the underground heat which is con.
stantly being conducted out of the
earth-in other words, the cooling of
the earth-the speed at which the earth
rotates on its axis as well as physical
properties Of rocks at high tempera-
lures.
The loss Of heat by conduction was
Lord Kelvin's first argument for limit
ing the age of the earth. He found that
If the earth had been losing heat in the
past with approach to uniformity for
20,OO0,OO0 years the amount Of heat
lost out Of the earth would have been