The morning times., 1897-01-25
THE OCEANS DEPTH.
At $500 Fathoms the Pressure Is
Very Great

The temperature at the bottom OF the
ocean is nearly down 20 freezing point, and
sometimes actually below it. There is
total absence OF light, as far as sunlight is
concerned, and there is an enormous press
ure, reckoned at about one ton u the square
in every 1000 fathoms. which is 160 times
greater than that of the atmosphere we
live in. At $500 fathOms the pressure is
thirty times more powerful than the steam
pressure of a locomotive when drawing a
train As late as 1880 leading zOOIOgist
explained the existence OF deep-sea ami
mass az sIch depths by assuming that their
bodies were composed OF solids and liquids
of great density and contaiRednO air. This,
however, is not the case with deep-sea fish,
which are provided with air-inflated swim
ming bladdeTs. If one Of these fish, in fun
chase after its prey, happens TO ascend
beyond certain level its bladder becomes
distended with the decreased pressure, aud
carries it, in spite of all it's efforts, still
higher in its course. In fact, members Of
this unfortunate class are liable to be
come victims to the unusual accident Of
falling upward and no doubt meet with
a violent death soon after leaving their ac-
customsd level and long before their bodies
reach the surface in a distorted and IN
natural state. Even ground sharks, brought
up from depth of no MORE than 500 faith
oms, expire before they gain the surface
The fauna OF the deep sea-with a few
exceptions hitherto only known as fossils
are new and specially modified forms
of families and genera inhabiting shall
low waters in modern times and have
been driven down to the depths OF the
ocean Oy their mere powerful rivals in
the battle OF life. much as The ancient
BritOns were compelled TO withdraw 70
the barren and inaccessible fastnesSes of
Wales. Some Of their organs have under
gone considerable notifications in CoTre-
SpOndence to the changed conditions Of
their new habitats- Thus down TO 800
fathOmS their eyes have generally become
enlarged to make the best 81 the faint
light which may possibly penetrate there.
After l 600 fatnOms these organs are
either Still further enlarged, OF So greatly
reduced that in some species they Gisap-
pear altogether and are replaced by enCr-
ElOusly long REFERS. The only light 90
great depths which would enable large
eyes to be- Of any service is the phOsph0-
reScence given cut by detp-sea animals.
We know that a tne surface this light
is often very powerful, and Sir WyviHe
Thomson has recorded one occasion on
which the sea at night was a perfect
blaze OF phCsphOTeseence. so strong that
lights and shadows were thrown on the
sails. and it was easy TO read the smallest
print" 1t is thought possible by several
HatuTaiiSts that certain portions Of the
sea bottom may be as brilliantly Hum
ined by this sort OF light as the streets Of
a European city after sunset Some deep
sea fish have two parallel rows Of small
circular phosphorescenJ organs running
along the whoIe length OF their bodies.
ana as they glide through the dark wa
ters Of the profound abysSes they must
look like model mailships with rows Of
shining orthcles.-Nineteenth Century,