Middlebury register. (Middlebury, Vt.) 1886-1937, 1892-11-25
AGE OF THE EARTH.
A FASCINATING STUDY THAT is eLU-
ClDATlNG A GREAT MYSTERY.


The Science oil Geology shows That the
Age Of the World Varies between 3D.
100000 and GSO,OOO,OO Years-How
These Computations Are Made.
AT the recent meeting of the British
association discourse was delivered by
the president. Sir Archibald Gerkie, on
one of the most interesting problems in
modern scicnce--the age of the world
Over century has elapsed since James
Hutton wrote his Theory of the Earth"
which was the first attempt tofOrmulate
chronology of creation in accordance
with the discoveries Of science: since
then knowledge has made vast strides.
and his followers have access 10 mass
of information which he did not possess.
Playfair and Kelvin improved upon his
work and now Gerkie and the school to
which he belongs have gone beyond
them.
Biologists have ascertained that the
rate at which erosion takes place can lie
measured; by applying their scale to the
sedimentary rocks they have formed a
hypothesis as to the time which has
elapsed since erosion began. To put the
proposition in similar language, the sur
face of the globe is constantly wearing
away under the influence of water and
wind. The portions which are worn off
are carried down to the sea or into hol-
lows, where they are deposited and form
sedimentary rocks. If we can ascertain
how long ii takes to form a sedimentarv
rock we can figure out when the progress
of wearing away and redcpOsiling began.
Sir Archibald states that on a reason
able computation the stratified rocks at
tain an average thickness Of 100. 600 feet.
The material of which they consist was
all washed down from high planes, de-
posted and left to stratifv. BY the in
spection Of liver banks il is found that
in places the surface Of the land which
has been carried down as sediment in
rivers ha, heon reduced at the rate of a
foot in 100 years, while in other places,
where the land was more stubborn OF
less flexible, ii has taken 6.eOO years t.
lower the surface one foot. The deposit
must he equal to the dCnudatiOu. Thus
we find thai while some of the sedimen-
tary rocks have grown foot in 13C
years others have taken $500 years tc
rise that height. Thus the period OF
time that was required to build up 100,
600 feet of sedimentary rock has varied
according 10 locality from $1,000 .00(
years to CN0.00O,0J0 years. 1t follow:
that the active work Of creation LASTED
for a cycle intermediate between these
two figures. The cycle varied with end
less succession of periods of disturbance
by volcanic force and glacial action
and the frequent submersion of dry
land, alternating with the emerging Of
continents out of the seas. These may
have retarded the growth of sedimen
tary rocks, but they cannot have accel
Grated it.
a study Of fossils teaches the stead,
uniformity with which the work o
creation proceeded. Since man began
to observe there has been no change il
the forms of animal and vegetable life
a few specie, have disappeared--not on,
new species mas been evolved. Not onl,
do we find the fauna and fora of ancien
Egypt as depicted on monuments which
are probably 5000 or 10000 years ole
identical with those which are found il
that country today, but shells which in
habited our seas before the ice age ant
grew in an ocean whose bed overlay tn
Rocky mountains are precisely the sam
species that are found III the Bay o
Monterey and the waters of the Chesa
peake. Ii is evident that there has beel
no essential change in the conditions o
life since these animals and these vege
tables We're first created, yet how vas
the shortest period which we can assigl
to the gap that divides us from that IT
mote epoch!
Little by little the geolCSist is liftin
the veil which covers the prehistOri
record of our planet The era whic
preceded the age of civilized man, wit
its vast rivers carrying down diluvia
floods to the ocean. and the burstin
forth Of mountain ranges from contraC
lions of the earth's crust has been painte
to the life. But no one has exercised hi
pencil on that preceding age, when tn
forests made way for clumpS of stunte
birch and willow, incessant snowfall
covered the plains, glaciers crept dow
from the north, and gradually a vas
sheet of ice half a mile thick drove inal
kind. with the mammoth and the rein
deer, to those fortunate regions which
like California, escaped the agony of til
= last ice age.
Nor have we any distinct perceptio
Of that subsequent age when the iC
melted or rtceded to the pole, or denS
tropical jungle grew up in the morass,
1t had left, swanps stemning with trol
zeal heat swanned with uncouth b;
. trachian and reptile life, trees of MOI
strous growth shed their shade owe
! shiny pools and black ooze, and in II
distance long mountain ranges who's
fontanel had not yet closed. poured
never ceasing food of lava down the
sides. This is Il page of history whic
is yet to be written, but the materia
[ are accommodating. and the historian wi
5 not be long wanting, San FrancisC
e Call.