Year: 1868

In 1858, Lieut.. Brooke obtained mud
from the bottom of the North Atlant-
ie, between Newfoundland and the
Azores at a depth of more than 10, 600
feet, or two miles, by the help of this
sounding apparatus. The specimens
were sent for examination to Ehren-
berg of Berlin, and TO Bailey of West
Point, and those able mieroseOpists
found that this deep sea mud was al
most entirely composed of the skele-
tons of living Organism-the greater
proportions of these being just like
the GlObigerine already known to oe-
cur in the chalk.


Thus far the work had been carried
on simply in the interests of science,
but Lieut.. BrOOkeis method of sound
ing acquired high commercial value
when the enterprise of laying down
the telegraphic cable between this
country and the United States was un-
dertaken. For it became a matter of
immense importance to know, not
only the depth of the sea over the
whole line along which the cable was
to be laid, but the exact nature of the
bottom, so as to guard against chances
of cutting or fraying the strands of
ALeAN NO1AAN AOtlCs AAC dlAN COll-
sequently ordered Captain Dayman
an old friend and shipmate of mine, to
ascertain the depth of the whole line
OF the cable, and to bring back speci-
mems of the bottom. In former days
such command as this might have
sounded very much like one of the i'm
| possible things which the young
prince in the Fairy Tales is ordered to
do before he can obtain the hand OF
the princess. However, in the months
of June and July, 1851, my friend per-
formed the task assigned to him with
great precision, without, so far as
know, having met with any reward
of that kind. The specimens of At
lantie mud which lie procured were
sent to me to be examined and report
ed upon.


The result of all these operations is
that we know the contours and ma. are
of the surface-soil covered by the North
Atlantic for q distance of LOO miles
from east to west, as we'll as we know
that of any part of the dry land.


1t is prodigious plain, one of the
widest and most even plains in the
world. If the sea were drained of
you might drive wagon all the way
from Valentia, on the west coast OF
ireland, to Trinity Bay, in Newfound-
land. And, except upon one sharp
incline, about two hundred miles from
Valentia. l am not quite sure that it
would be necessary to put the skid on,
so gentle are the aseents and descents
upon that long route. From Nalentia
the road would lie down hill for about
200 miles to the point at which the
bottom is now covered by ], 200 faith
Oms OF sea-water. Then would come
the central plain, more than l,OOO
miles wide, the inequalities of the
surface of which would be hardly per-
eeptible, though the depth of the
water upon it varies from 10000 to To-
600 feet; and there are places in which
Mont Blanc might be sunk without
showing its peak above water. Be
yOnd this, the ascent on the American
side commences, and gradually leads,
for about 500 miles, to the Newfound-
land shore. .----..


Almost the whole of the bottom of
this central plain (which extends for
many hundred miles IN a north and
south dfrectiOn) is covered by fine
mud, which, when brought to the
surface, dries into grayish-white fri
able substance. You can write with it
OF blackboard, ifyOu are so inclined,
and to the eye it is quite like very soft,
grayish chalk. Examined chemically,
itprOyed to be composed almost wholly
of carbonate of lime and if you make
a section of it in the same way as that
of n piece of chalk was made, and
view it with the microscope, it pre-
sents innumerable GlO5igerin6 i'm
bedded in the granular matrix.


Thus this deep sea mud is substan-
TALLY chalk. 1 say substantially, be-
cause there are a good many minor
differences /; but as these have no bear
ing upon the question immediately
before us-which is the nature of the
GtobigeriIl0e of the ehalk-it is unnee=
essaTy TO speak of them.