lead with a lump of
grease, to which more or less of the sand or mud, or broken shells, as
the case might be, adhered, and was brought to the surface. But, however
well adapted such an apparatus might be for rough nautical purposes,
scientific accuracy could not be expected from the armed lead, and to
remedy its defects (especially when applied to sounding in great depths)
Lieut. Brooke,[61] of the American Navy, some years ago invented a most
ingenious machine, by which a considerable portion of the superficial
layer of the sea-bottom can be scooped out and brought up from any depth
to which the lead descends.
In 1853, Lieut. Brooke obtained mud from the bottom of the North
Atlantic, between Newfoundland and the Azores, at a depth of more than
ten thousand feet, or two miles, by the help of this sounding apparatus.
The specimens were sent for examination to Ehrenberg [62] of Berlin,
and to Bailey of West Point,[63] 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 Lieut. Brooke's method of sounding acquired a high
commercial value, when the enterprise of laying down the telegraph-cable
[64] 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.*
* See Appendix to Captain Dayman's "Deep-sea Soundings in
the North A
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