The morning news. [volume] (Savannah, Ga.) 1887-1900, 1891-11-30
The Age of the World.

Assuming that the average rate of denu-
dation in past geological ages did not ma
terielly differ from what it is at present,
aud that the total quantity Of s.ratified
rock would, il uniformly spread over tho
whole globe, form a layer 200 feet in thick
ness, we have a total period of 1000 multi
piled by 900 multiplied by four, or "a 900, 900
years. This, however. only represents the
time necessary to deposit the rocks which
have been formed by denudatIon from
older rocks and these again from rocks Of
still greater antiquity. Assuming that the
existing stratified rocks have thus passed
three times through denudation and de-
position, we have a period of Y, 200, 600
years. DR.. Haughton calculating from the
observed thickness OF the rocks down to the
miocene tertiary, and assuming period OF
S,6l6 years for each foot deposited on the
ocean bed, finds, for the age of the st nti-
fed rocks a period of !, 1926, $50 900 years
Assuming the rate of denUndation. however,
as ten times greater in ancient times than
at present, and adding one-third for the
period since the miocene tertiary, he arrives
at final result of 200,0O0.000 years. Dr.
Croll doubts the validity of Prof
Haughton's assumptions especially the
total thickness he assumes, namely, IN, 300
feet. or over thirty-three miles. A. r. Wal
| lace, adopting DR.. Raughton's thickness, but
assuming the sediments to be deposited
dlOlB u DoLt VI eulTLy ullI63 htGe rOuDQ C0e
| whole coast line of the globe, finds with au
assumed liquidation of one foot in 5000
years period of 2S,000,000 years. This,
| however, on DR.. Croll's assumption of refo. =
nation and denudation repeated severa
times, would be merely fraction Of the
| time required. DR.. Croll further shows
| from the evidence Of remarkable faults
| in various parts of the world, with down
throws" ranging from 8, 900 to 10000 feet,
| the enormous amount of solid rock which
must have been denuded of the surface OF
the earth during the progress OF geological
history. He estimates that three miles of
rock have boon removed since the beginning
of the old red sandstone. This would iudi-
cate period Of 100000 years. Assum-
ing that the period before the old red sand
stone was equally long we have 10000, 00O
years as ths minimum duration of gen.
logical time" These enormous periods of
time do not, however, seem to satilfy the
demands of the biologists and the sup
porters Of the Darwinian theory. Judging
from the fact that almost the whole Of the
tertiary period has besn required to convert
the ancestral eohippus into true horse, u
Prof. Huxley believes THAT in order
to have time for the much greater change
of the ancestral ungulata into the two
| great odd toed aud even toed divisions (of
| which change there is no tracs, even among
the earliest eocene memmalsl we should re-
| Quire larger portion, If not the whole OF
the meSozoic or secondary period" and still
| longer periods are demanded for the evolu-
ton of other animals, 80 that on the
| lowest estimate we must place the origin OF
the mammalia far back in paleozoic times. y
| Mr.. Wallace speaks of possible periods OF
1000, 900 and even 50O.O00,000 Of years.