The Indianapolis journal. [volume] (Indianapolis [Ind.]) 1867-1904, 1897-07-18
AGE OF THE EARTH.
Lord Kelvin Says 1t Has Been Habit
able 3O,OOO,OOO Years.
New York Herald.


At last we know exactly how old the earth
Is, for Lord Kelvin, the eminent British
savant has, after the calculation Of years
reached the definite conclusion that this
terrestrial sphere has been such for thirty
million years This is not the chimercal
assertion of a theorlst, but the result Of
long and laborious study by perhaps the
man best qualified of all to make an au-
thoritative statement to humanity.
1t is of the utmost Importance to geolo-
gists, many of whom have doubted whether
there was any data on which a definite cal
culation could be based. This doubt Lord
Kelvin has removed, and he gives absolute
events of different periods of the world S
history which he states are perfectly sus-
ceptible to proof sufficient to satisfy the
most carping critic.
Lord Kelvin has just issued a formal
statement in the matter which outlines his
belief and the reasons therefor. In support
of his statement that there must have been
surely as there will be a definite end, he
referred to his REPUTATION of the doctrine Of
uniformity in geology, with IT'S accompany
conducted out of the earth at its present
yearly rate the globe twenty million years
ago would have been q molten, IL not a
gaseous, mass.
Another argument against the huge
lengths of time required by the older geol-
OgistS is sought from the constantly dmin-
ishing velocity Of the earth's rotation, ow-
ing to the tides 1t is shown that thou
sand million years ago the earth was re-
VolVing faster than at present, and conse-
Quently that the centrifugal force was
greater. If the globe had become consoli-
dated when travelling at this faster rate it
would have possessed greater oblateness,
and the length OF it's equatorial radius
would have been six and a half klometers
more than at present. To judge by the
properties of rocks and by underground
temperatures the date of the solidihcation
of the earth was most probably twenty or
thirty million years ago.
The origin of the atmosphere Is then dis
cusSed. AT the time OF soHd1ncatlon there
could have been no free oxygen, so far as
can be seen, and no chemical reaction by
and sunlight must have come into play TO
prepare our atmosphere in the course OF a
few hundred thousand years
A serious geological question is the mode
OF production OF the ocean oeplhs ana the
eminences of the continents. Many phenom-
ena are doubtless due to strain on cooling,
but that does not afford a sufficient eXpla-
nation in this case. Lord Kelvin thinks the
cause is 10 be found in change of density by
disqualification. Perhaps the strongest argu-
mant against unlimited geological time is
afforded by consideration of the heat of the
sun which, according TO the most recent re-
searches and corrections, may have illumi-
mated the earth for somewhere about tWen-
" million years.
Professor Poulton wanted time to find in
vertebrate ancestors for the Verlebrates on
the Cambrian rocks, and Professor Perry
had attempted TO relieve biologists Of the
burden put upon them by physicists, and
once more provide them with an endless
latest geological estimate OF the time re-
quired for the formation of all strata since
the beginning of the Cambrian rocks was
seventeen million years, and he can scarcely
be described as merely a malicious physicist
trying TO curb the aspirations OF the biolo-
gist when he says that this earth could not
have been habitable globe for more than
thirty million years.