Evening star., 1932-04-08
MOUNTAINS BUILT
BY CONCLUSIONS
INSIDE OF EARTH
Arthur Holmes, English GeoI-
ogist, Disputes Old Theory
of CooIing-off Process.
INTERIOR OF LIQUID
HAS thighs AND LOWS"
Age of Rock Deduced, Academy of
Sciences Told, by Lead From
Disintegrated Radium.
BY THOMAS r.. HENRY.

Mother Earth is getting livelier as
she grows older.
The eternal hills, resulting from her
internal activities, are mere striplings,
relative to the geological time chart.
These facts were stressed before the
night by Arthur Holmes, noted English
geologist, in presenting evidence for
new hypothesis of geophysical mechan-
les to explain the phenomena of noun
tain building. Shiftings of oceans and
continents, anomalies Of gravity and
changes in the length of the day.
DR.. Holmes pictured an earth with
solid crust about 60 miles thick float
ing upon a liquid but extremely rigid
substratum. which is disturbed by con-
slant convention currents" due to mi
mute amounts of uranium, thorium and
other radioactive. heat-producing ele-
ments in its composition. These pro-
duce highs and lows" in the sub
stratum. just as do convection currents
in the air. The thin, solid layer of
crust Is sentitive to these disturbances.
registering its responses by mountains
and ocean deeps.
Former Theory Disputed.
Mountain building has been gen.
orally considered in the past, DR.. Holmes
said, as due to the gradual cooling of
the globe and consequent shrinking.
Under this theory, mountain ridges are
like the ridges on the skin of an apple
which has lost its moisture. But, he
pointed out, the relative age of the
mountains and the rate of their for
nation at different periods show this
explanation Is inadequate For at least
500 100000 years the crust of the earth
has been cool enough to support life,
DR.. Holmes pointed out, yet examina-
tion Of the radioactive material in the
rocks shows the mountains contain very
little Of the crust material dating from
this earliest period.
The age of rocks, he explained, can
be dedueed with considerable accuracy
from the amount of the particular kind
of lead which is the final product of the
disintegration of radium contained In
them. Throughout the geological eras,
from the pre-Cambrian to the present,
there has been a steady increase in
the number OF frequency of births of.
mountain systems.
Now, DR.. Holmes explained the great
mountain chains of the earth fall con-
ing an extended circle around the North
Pole and the other around the South
Pole. There are numerous breaks in
both systems.
Starting with the North American
Rockies. he pointed out, the mountain
system does not continue southwark to
JON the Andes, but turns eastward to
PICK up the Appalachians, then swings
across the Atlantic, crops out in the
Sierra Nevada mountains in Northern
SPAIN, then picks up the Alps and con-
tinues across Asia. The southern sys-
tem, he said, consists of the Andes
the Atlas Mountains of Northern
Africa, parts of the Himalayas, the
mountain chain of New Guinea and
the great mountains of the Antarctic
continent.
Mountain -Inclosed Sectors.
Thus, the earth is divided roughly
INTO two mountain-incloSed sectors. a
northern and southern. This is about
what would result, he said. if two cent
ers OF convection disturbance are as
Sumed to exist In the earths sub
stratum approximately in the centers of
these sectors. AS a compensation for
the mountains there would be great
ocean deepS such as have recently been
found by submarine expeditions
DR.. A. F. Veldex-Meinez, Dutch geo
physicist, who has Just returned from a
submarine expedition to explore the
great Bartlett Deep of the West Indies
and to determine the extent and direc-
ton of so-called gravity cracks" run
ming around the earth, commented that
DR.. Holmes theory might afford an
almost perfect explanation of these
anomalies
Dr.. Holmes showed by a mechanical
model just how such a mountain svs-
tenn as the Alps could be produced bv
mole in the sub-stratum underneath
1t such as might have been produced
by convection current with the re-
sultant folding of the surface rocks like
layer of cloth which Jams while being
pulled through a.hole in a board table.
Internal Source of Heat.
If the earth was simply living on its
original heat which it had when it was
torn away from the sun, Dr. Holmes
said, only about 30,000,000 years could
have elapsed since its crust became
solid. But the discovery of radioactive
minerals very widely distributed in its
rocks shows that there is an internal
source OF heat which allows at least
800 100000 years since the thin crust
cooled to the crystallization point.
Examination of the cruStal rocks, he
said, shows so much radium that, if the
same proportions held through the en-
tire mass, the earth would be gaining
heat at about 10 times the rate it is
losing it. If this were true, the globe
long since would have become too hot
for life, SO geologistS are forced to the
conclusion the radioactive elements
must largely be concentrated in the
thin crust itself, with only very minute
amounts in the subStratum. There,
however. the conditions of pressure are
so different a liquid state is maintained