The watchman and southron. [volume] (Sumter, S.C.) 1881-1930, 1922-04-22
The Unknown j.;
Sea Bottom

Explorers and geoSraphcrs who
have been signing for new lands to
conquer may find their best field
/. OF endeavor. pardoXically. in the
sea. Now that the United States
Navy has perfT cted a device for
measuring the depths Of water by
sound waves without going through
the tedious process of lowering
sounding lines ii should be possible
to add greatly to the relatively
water portion of the earth. The
little we know about the under
region is brought out in the follow
Importance OF this little explored
ing bulletin issued from the Wash
ington. D. c. headquarters Of the
National Geographic Society:
.'Whcn il is realized that nearly
threc-fourths of the surface Of the
globe consists Of water it is rather
remarkable how little we know OF
the vast surface of the solid sphere
which lies under this screen OF
liquid. The greater portions of our
continents are mapped even 10 the
smallest details. and our harbors
ard the shallow waters closely off
shore are fairly we'll charted; but
once the edges of the continental
shelves are passed the features OF
the sea bottom are represented only
by q few somewhat vague contour
lines laid down between rather in
frequent points Of soundings.
Not Sure Of Greatest Depth
I'VE know without doubt that
the highest point on the earth is
the peak Of Mt. Everest which e%-
tends above sea-lcvcl for 29,002
feet-or 3S feet less than 1-2
miles. On the other hand we
can only speak OF the deepest abyss
yet discovered for one great pit.
hidden in the depths Of the ocean,
has scarcely established its title
to first place in recent years when
it has been surpassed by a deeper
one; and it can hardly be believed
that the deepest Of all has yet been
discovered.
School children were taught a
few years ago that the deepest de-
preston in the earth's surface was
near the Fiji Islands and that it
! was 30.133 feet deep. Since then
the deepest hole on earth has been
successfully kermadec Deep.
northeast of New Zealand. 30,9Sp
feet: Nero Deep. southeast OF
Guam. .1,616 feet; and the present
! holder OF the record. Philippine
Deep, cast of the Philippine Islands
32.0S9 feet. This greatest known
depth therefore lies six miles and
409 feet below the surface Of the
sea.
Like Scratch on Billiard Ball
THE greatest range vertically OF
the earth's surface is between the
bottom Of Philippine Deep and the
top Of Mt Everest, a distance Of ap-
proXimately 11.6 miles. This
seems tremendous distance un-
til it is compared With the diameter
Of the earth which. near the latl-
! tudes Of these great physical fea-
lures. is approximately 5000 miles
! On a globe with diameter Of eight
i inches instead of 5000 miles. this
maximum range Of depressions and
! heights would be represented by a
scratch little more than a hun
j dredth Of an inch deep. The small
est division on household ruler
| is one sixteenth Of an inch. The
scratch would be less than a fifth
of such division in depth On a
billiard ball one could hardly
scratch lightly enough with a pin
! to represent the great Philippine
Deep. and few grains of talcum
powder would stand for Mt. Ever
est. The smoothest orange that
grows has much greater irreSu-
larities on its skin in proportion to
! its size than those given to the
earth by all its peaks and valleys.
Cone who studies the earth
comes to realize that in a sense the
continents arc subordinate to the
t great ocean basins. The total
volume Of these depressions below
sea-leyel is many times greater
than the volume Of the land that
rises above the sea. If the entire
! land surface were leveled down an
ocean nearly two miles deep would
sweep over every square foot of tho
surface Of the globe. The condi-
ton of the continents might at first
glance be considered precarious,
but dry land has formed u consid-
cradle part of the surface of the
earth for millions of years and VIII
probably remain for long time
to come. 1t has been estimated that
! less than four cubic miles Of solid
material is carried into the sea by
water annually. At this rate, leav-
ing out of consideration upheavals
and subSidcnces due to earthquakes
and other causes. it would require
more than 6.000.000 years for all
the present land to be washed into
/ the sea"
Control OF MoIcS.
Clemson College. April Is
Molcs generally pass through their