The Democratic banner. (Mt. Vernon, Ohio) 1898-192?, 1913-11-11
UNDER THE OCEAN
Changes In the Sea Floor From
Shore to Shore.
The BIG MlD-ATLANTlC RIDGE.

u starts at Iceland ana blseots tne
Ocean Down Almost to Cape Horn.
! In Places II Rises Above the Surface,
Forming Groups Of islands.
A sketch of the landscape" of the
ocean bed is given by DIR. A. E. Ship
ley in an article in the Edinburgh Re
view:
THE passengers and the crew of a
liner racing over the surface of the
Atlantic are apt to imagine that under
them Is q vast layer of water of vary
ing depth sparsely inhabited by few
fish. As matter of fact, the whole of
this great ocean is teeming with life.
If instead of taking ship we could take
to the water and walk across the bed
of the Atlantic to America, starting
from the shores of western Europe, we
should in effect be travelling through
succession of new countries. Not only
would the surrounding physical condi-
tions vary as we advanced, but the
animal aud plant life would vary in
correlation with the altering physical
conditions.
"Walking farther and farther toward
the depths of the Atlantic, we should
soon lose all sight of the algae, and the
shallow water fish-the plaice and sole,
whiting, skates, dogfish and others and
cod-would give way to the megrim
and the hake. The sea floor would
gradually change from rock or gravel
or stones to sands and ultimately to
mud or oozes of various tints. their
original colors often modified by the
, action of the decomposition of organic
particles in them and on them. All
these finer deposits are derived from
the neighborlng land and are blown
seaward by olfshore winds or washed
down by rains and streams and carried
out to the sea by rivers.
"'rhe distance to which fine matter in
suspension may be carried is very
great The Kongo is said to carry its
characteristic mud as far out to sea as
coo miles. and the Ganges and the
Indus as far as 1000 miles.
Except in the neighbOrhood of such
great rivers subaqueous traveller
would soon pass beyond what Sir John
Murray has called the mud line,'
line that limits the terrigenous deposits
everywhere surrounding dry land.
Having reached this limit, we must
proceed warily. for at the mud line.
at an average depth of a hundred
fathoms, we shall find ourselves at the
edge of the continental shelf, that rim
which extends seaward to n varying
distance from all land areas. the rim
on which Great Britain rests. Beyond
Hes the continental slope. preclpice
more or less abrupt and more or less
high. descending by steep declines or
terraced cliffs until depths of 1000
fathoms are reached
The Atlantic, compared with the
other great oceans, has an unusually
large area OF comparatively shallow
water. OF its total area 275 per cent
IS covered by water less than 1000
fathoms deep: IS per cent lies between
1000 and 1000 fathoms and Al per cent
between 1000 and 5000 fathoms; the
remaining rs per cent is still deeper.
'At the foot Of the continental slope
lies an illimltable plain of a uniform
dull. grayish buff Color Hat and fea.
turcless as the desert ana only dlversi
fed by nn occasional as yet uncovered
rock or wreck or the straight line of d
recently laid cable. This plain con
tlnues with scarcely change in seen
cry or In level until we approach the
great mld-Atlantic ridge. AS Bruce
has shown. this ridge. which roughly
bisects the Atlantic. extends from Ice
land as far south as ifty-three degrees
Of south latitude, with n slight and
quite inexplicable break just under the
equntor. The ridge runs almost parable
with the eastern contour OF North anC
South America, which. IN turn. as tho
ordinary map will show roughly cor
responds with the western contour OF
Europe and Africa. From time to tim,
the ridge rises above the surface of tn,
water, as In the Azores group. st
Pauls rocks. Ascension. Tristan da
Cunha and Cough island.
Having ascended the eastern and
descended the western slope OF this
mid-Atlantlc ridge we should agair
traverse plains of grayish ooze fal
more extensive than any level land
tract known to geographers, and as We
approached the American coast we
should gradually pass through. In re
verse order. the zones of life traverset
when leaving Europe On the eastern
coast OF America the slope Is much
more gradual than on the western
coast of southern Europe and Africa"