The Washington times., 1922-01-15

K 1ATURALLY enough. the globe We
IN live on is Of intense interest to sci.
ence Biologists are studying It tire
lessly, and very recently some entirely
new and extremely interesting facts have
been discovered about our earth.
Mountains float. Their bases rest. many
miles below the surface level Of the earth.
upon yielding masses of inconceivably hot
material
Mountains are high because, cubic yard
for cubic yard. they weigh less then val.
leys.
To illustrate the proposition. take basin
Of mercury and place IN Il several blocks
OF different metals. just alike In cross
section and each weighing one pound Each
will dsplace the same amount Of mer.
cury-will sink. In other words. to the same
depth. But the block Of lighter material
fsay. silver) is taller than the block Of
gold. and so II stands mp higher
II the crust Of the earth were cut by
vertical planes into blocks 100 miles square.
with their bases sixty miles below sea
level these blocks would be OF equal
weight.
We observe however that some Of them
stand higher than others. rising into noun
tains Hence their material must be lighter
than that Of the blocks In low.lying areas
The lighter the stun OF which block Is
made. the taller It stands.
This interesting and novel idea has been
worked out by Dr. William Bowie. chief Of
the division OF geodesy In the United States
Coast and Geodetic Survey. and Professor
John F Hayford Of Northwestern Uni
versity.
The rigid crust OF the earth is q rocky
shell. its thickness reckoned at about sixty
miles. Relatively to the size Of the planet,
II is thinner than the shell OF an egg
The popular notion that the contents OF
this shell are molten and liquid is. how
ever a gross error n that we're true, the
earth would act IKE A liquid globe IN re-
Spouse to the attraction Of the moon and
the sun The thin shell could not hold the
ball of liquid rigid. and we should have
earth tides equal to the tides OF ocean.
As a matter OF fact. the earth is solid
all through to its centre. its core being
held by tremendous pressures to . Rightly
equal to that OF steel.
But when we use the term solid" what
do we mean? Wax Is solid. Tallow can
dies are solid. Taffy is solid. Yet pres.
sure will make them flow. II We 20 down
Gar enough through the earth's crust We
.haIl reach a level where temperature and
other conditions change the material from
a resisting solid to one that Yields 10
stresses and flows.
Apply pressure to gold. copper or lead,
and when they can no longer resist they
now II Is the same way with rocks; we
have seen them do It. In the Culebra Cut
on the Isthmus OF Panama, when the Canai
was dug out. the pressure on both SIDES
nusbed the rocks up from the bottom oil
the excavated prism, greatly adding to the
labor that had to be performed.
The earth's crust in all its parts Is main
tanned in a state Of equilibrinm-a condi
tion which could not exist unless the 100
mile.suuare blocks already mentioned were
~ equal weight. That they are OF equa
weight has been definitely proved b!
veodetic and astronomical observations.
zach block contains 100000 cubic miles
Of material below sea level and weigh'
,hout S, 500, o0o, 900 900 900 short tons.
But Il Is a matter OF everyday observa
ton that on the surface OF the earth ma
terial in large quantities is continually be
ing carried and transferred from one blocl
n another. Mountains are washed ava!
nv rain ana worn away by winds; sed'
mepts In millions OF tons are brought dow
By rivers and deposited along the seashore