ooke obtained mud from the bottom of the North Atlantic,
between Newfoundland and the Azores, at a depth of more than 10,000
feet or two miles, by the help of this sounding apparatus. The
specimens were sent for examination to Ehrenberg of Berlin and to
Bailey of West Point; and those able microscopists found that this
deep-sea mud was almost entirely composed of the skeletons of living
organisms--the greater proportion of these being just like the
Globigerinae already known to occur in the chalk.

Thus far the work had been carried on simply in the interests of
science; but Lieutenant Brooke's method of sounding acquired a high
commercial value when the enterprise of laying down the telegraph
cable between this country and the United States was undertaken. 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 that costly rope. The Admiralty
consequently ordered Captain Dayman, an old friend and shipmate of
mine, to ascertain the depth over the whole line of the cable and to
bring back specimens of the bottom. In former days, such a command as
this might have sounded very much like one of the impossible 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, 1857, my friend performed the task assigned to him with
great expedition and precision, without, so far as I know, having met
with any reward of that kind. The specimens of Atlantic mud which he
procured were sent to me to be examined and reported upon.

The results of all these operations is, that we know the contours and
the nature of the surface soil covered by the North Atlantic for a
distance of I,700 miles from east to west, as well as we know that of
any part of the dry land. It is a prodigious plain--one of the widest
and most even plains in the world. If the sea were drained off, you
might drive a wagon all the way from Valentia on the west coast of
Ireland, to Trinity Bay in Newfoundland; and except upon one sharp
incline about 200 miles from Valentia, I am not quite sure that it
would even be necessary to put the skid on, so gentle are the ascents
and descents upon that long route. From Valentia the road would lie
downhill for about 200 miles, to the point at which the b