Stellwagen's
Cup (Sounding Device)
The
following information is excerpted from Reports of the Superintendent
of the Coast Survey
Report
of the Superintendent for 1860
For obtaining specimens of the bottom. - The only satisfactory
test of having reached the bottom of the sea at considerable
depths being the bringing up of a specimen, this has been a
subject of constant study with us. The different instruments
invented by Lieutenant Stellwagen, Commander Sands, Lieutenant
Craven, Lieutenant Berryman, Lieutenant Brooke, and other officers
of our navy, are all in use for different kinds of bottom, and
according to preference given by different hydrographic chiefs.
The
one most commonly used in these explorations has been Lieutenant
Stellwagen's invention - a cup placed below the sounding lead,
covered by a valve of leather, which slides up the stem of the
cup and opens when the lead is descending, closing when it is
raised. The weight of the lead, and the turning of the cord
generally, suffice to sink the cup into the bottom, filling
it; and when the valve is made to close tightly by a piece of
flexible leather below the stiff disk, the specimen is not washed
out as the lead is drawn up.
In
Commander Sands's sounding apparatus a spring keeps an outer
cylinder over an opening in an inner hollow one, until it reaches
the bottom, when the outer cylinder is forced upwards, and the
opening at the side of the inner one, which, having a conical
termination, penetrates the bottom, permitting a specimen of
the bottom to pass in. On raising the lead the spring forces
the outer cylinder over the opening, preventing the specimen
from being washed out. The only very deep soundings being, as
a general rule, in soft bottom, Sands's specimen cylinder is
admirably adapted to that class of work.
Appendix No. 17. Lecture on the Gulf Stream, prepared at
the request of the American Association for the Advancement
of Science. By A.D. Bache, Supt. U.S. Coast Survey. pp. 167-168.
Report
of the Superintendent for 1854
"Among
the instruments of every-day use in our work , to which much
ingenuity has been applied, is that for bringing up specimens
of the bottom of the sea. The use of Stellwagen's lead is common
in all our parties, and the apparatus meets with general approval.
Lieut. Comg. Craven has invented a box for bringing up deep-sea
specimens while running lines, which is convenient and efficacious....
To the same officer we owe an adaptation of the Massey's lead
to very deep soundings, which is in the highest degree important,
and the use of which has served to bring out in bold relief
the imperfection of the ordinary sounding-line when thus applied.
Lieut. Comg. Craven has also made an instrument for measuring
the set and drift of submarine currents, which he is engaged
in perfecting by experiment. In this connection, I should mention
, also, the ingenious syphon tide-gauge of Lieut. Comg. Stellwagen,
a model of which he has successfully tried, and which he is
now authorized to put up on the full scale for a regular working
trial...." pg. 13.
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