The Forest Republican. [volume] (Tionesta, Pa.) 1869-1952, 1880-06-23
The Deep Sea.

Some interesting results OF recent
deep sea explorations were concisely
stated in late lecture at the royal in
stitution, London. FOur-seventh, or
nearly three fourths of the surface of
the earth, are covered by sea. The
average depth of the ocean is, accord
ing to the latest calculations of Otto
Krummell, about l,677 fathoms, or
somewhat over two miles. The great
est depth known to exist was discovered
by the United States ship Tuscarora,
near The Kurile islands, in Northeast
Pacific. 1t is 1855 fathoms, or about
five and one-quarter miles. The hig h.
est mountain existing is of about the
same height as the deepest sea is deep.
Mount Everest is 1883 fathoms in
height. So Insignificant, however, is
the total volume of land raised above
sea level in proportion to the vast cav
ity occupied by the sea, that were this
cavity emptied of its water, the whole
of the land now above sea level could
be shoveled into it twenty-five and
half times over before it would be hlled
I'D to the present sea level.
Nevertheless, the depth Of the oceans,
great as it is, is as nothing in compari-
son with the vastness of their extent OF
surface. AS MIR. Croll has said, the
oceans in relation to their superficial
area are as shallow rs a sheet of water
100 yards in diameter and only an inch
in depth. The sides of the ocean basins
are not Mt all steep. They are mostly
so little inclined that an ordinary loco
motive engine could run up them In
straight line with ease. Their lncllna-
tion is usually not more than three or
four degrees or less. Around some
oceanic islands the slope is greater. The
steepest slope known is at Bermuda,
where there is an inclination of nearly
| twenty degrees from the edge of the reef
to 1000 fathoms. There are no such
| things as mountains and valleys on the
deep sea bottom. Animals cannot slip
! down against their will into the depths,
but must move deliberately into them,
and travel long Journey toreach them.
The pressure eXerted by the superin-
cumbent water at great depths is so
great as to be almost beyond concep-
ton. 1t amounts roughly to ton on
square inch for every 1000 fathoms OF
depth. about l66 times as much as the
pressure TO which people are subjected
on land. At the greatest depths the
pressure is about four tons aDd a man.
Vast though this pressure is, 1t is, now
ever, only about one-elghth OF thaI
! which Professor Abel ana captain
Noble have measured, as produced IN
their experiments on guppowder. The
deep sea animals, being completely per-
meated by fluids, are probably no more
conscious of pressure acting upon them
than we, and, so long as they move
slowly from one depth to another, are
most likely unaffected by the consequent
changes of pressure.
With regard TO the temperature OF
the deep sea waters, the conditions
which would affect animals are COM
paratively simple. Nearly all over the
ocean the temperature at 500 tathoms IS
as low as forty degrees 1. :, and this is
the case even Immediately under thf
equator in the Atlantic and Pacih'
oceans. Below 1000 iathoms the tenn
perature is never more than n few de
grees above freezing point, excepting
in the peculiar easeslof land-lockeo
seas, such as the Sulu sea.