The Union and journal., 1869-12-10
The Bottom of the Ocean.

In 1858 Lieutenant Brooke obtained
mud from the bottom of tho North Alan
tic, between Newfoundland and the
Azores, mt u depth of more than 10000
feet or two miles. by the help ofhis sound
ing apparatus. The specimens were sent
for examination to Ehrenberg, OF Berlin,
and to Bailey, of West Point and those
able microscopists found that his deep
sea-mud was almost entirely composed OF
tho skeletons of living Organism-the
greater proportions of these beingjust like
the Globigerinm already known to occur
In tho chalk.
Thus far work had been carried on sim
ply In the interests of science, but Lieut..
Brooke's method of sounding acquired q
high commercial value when the enter
prise of laying down tho telegrnphic cable
between England and the United States
was undertaken. For 1t became matter OF
immense Importance to know, not only
the depth of the ocean over tho whole limo
along which the cable WIS to be laid, but
the exact nature of the bottom, 50 rs to
guard against chances of cutting or fiay-
ing strands of that costly rope. Capt.
Dayman, therefore, was told to ascertain
the depth of the whole line of the cable,
and to bring back the specimens of the
bottom. In former days such command
Ms this might have sounded very much
like one Of the impossible things which
the young prince Is ordered to do before
he can obtain the hand Of the young prin-
cess. However, In the months OF juno
and-July, 1867, tho Capt. performed the
task assigned to him with great precision,
without, so FAR rs we know. having met
with any reward Of that kind.
The result of NIL these operations Is, thnt
we know the contours and nature Of the
s,irfacc-soil covered by tho North Attain
tic for distance of LOO miles from cast
TO west, rs well rs We know that Of any
part of the dry land.
1t Is prodigious plain, one OF the Wild
est and longest plains In the world. II the
sea were drained of, you might drive q
wagon all tho way from Valcntia, on the
west coast Of Ireland, to Trinity Bay, In
Newfoundland. And, except on one
sharp incline, about two hundred miles
from Valencia, we arc not quite sure that
II would even be necessary TO put tho skid
on, so gentle ardsasccnts and descents on
that long routc. From Valentia tho road
would lie down hill for about two hundred
miles to the point nc which the bottom Is
now covered by LOO flthonis Of sea wa
ter. Then would come the central plain,
more than one thousand miles wide, the
inequalities of the surface Of which would
hardly bc perceptible, Though tho depth OF
the water upon It varies from 10000 to|
1900 feet; and there are PLACES In which
Mount Blanc might be sunk without show
ing It's peak above water. Beyond this,
the ascent on tho American side conf
mences. and gradually leads. for about
800 miles, To the Newfoundland shore.
Almost the whole Of the bottOm OF this
central plain (Which extends for many
hundred miles In n north and south direc-
tion) Is covered by u fine mud, which.
when brought 10 the surface, dries into q
grayish.white friablc substance. You can
write with this on u blackboard. II you
arc 50 inclined. and to the eye It Is quite
like very son srayish chalk. Examined
IL proves TO be composed nl- |
most wholly Of carbonate of lime, and IL
YOU make section Of II In the same way |
rs that of % piece of chalk Is made, and
view II with the microscope, II presents
innumcrablc Globigerinn embedded In
the granular niatrix.
Thus this deep sea mud Is substantially
chalk. We say substantially, because
there are good many minor differences;
hut ss these have no bearing upon the
question Immediately before us-wh!ch is
the nature Of the GlObigerinn Of the chalk
1t Is unnecessary to speak Of them.