New national era. [volume] (Washington, D.C.) 1870-1874, 1871-04-06
The Gulf Stream-IfsO Origin.

The Gulf Stream is nothing more nor less
than great thermal spring in the ocean, and
Is IN every respect similar TO one on land TO
produce this great oceanic phenomenon we
have only TO substitute the arctic basin for an
elevated mountain and, instead of under
ground temperature derived from few square
rods of the interior, take that afforded by AS
100000 of square miles 90 600 feet nearer the
interior, and the thermal spring in the ocean
is formed. The difference is only quantitative.
These currents, which rest on the bottom of
the sea, are colder and denser than ice, and
could not be lifted to the surface were il not
for the. forces from the interior. Abstracting
that heat from the crust which underles the
sea; it will naturally be suggested that this
process must chill this crust to a greater depth
than the atmosphere does terra irma, and thus
render the effective force of the interior as
feeble on the bottom of the sea as on the sur
face of the land hemispheres. Fourier, from
observations made on terra firma, finds that
the loss of heat which the globe daily sustains
is too feeble to play any important part If he
be correct, the temperature of the oceanic
waters could never have been obtained from
the amount of heat which passes through the
land hemiSpheres. Yet there is this actual
presence of heat-which we have shown cannot
have accumulated from the solar rsy-and the
only way open is to associate il with some law
TO which it either now is or has been related
1t will be admitted that when these waters
were OF such high temperature as to produce
a tropical climate around the shores Of Green
land, they did not receive that heat from the
sun, but from the interior. Seeing that at one
time there was law which produced so high
Il temperature through this crust, why should
we aiscredit its present existence, when the
temperature has only sunk 30 degrees since
Heat always preserves the coeficient of ex-
panslon, and when matter is in fluid state this
coefficent may exist. Whatever inequalities
may take place in the relation of these con-
densed atoms on the crust, the form of the
fluid interior remains unchanged inasmuch as
the expansion continues. AS the heat became
lost from the interior of the earth, and its
fluid diameter diminished, these water hemis-
pheres, still retaining their reciprocal relation
to the centre, went down to a corresponding
depth. The crust which underlies the sea was,
therefore, always distance equaling the
oceans depth nearer the fluid part. How, we
would ask, could $4,000, 900 of square miles
of water, $4,000 feet deep, be kept at tenn
perature OF 10 degrees unless an igneOus fluid
world, as large as the planet Mars, existed
directly under them? This is by no means
speculation, when we have considered the
amount of heat contained in single cubic foot
Of water at this temperature. The cause which
produced tue SINKING OF the water hemlsph
in the first instance has always continued. AS
the solid crust of the globe condenses and
contracts its folds, the crust which underlies
the sea being the lower fold, is forced into
much closer relation with the fluid part, The
calculations made by Fourier are, therefore, of
no value, for they were formed, according to DR..
Mayer, from observations made on terra frma
under clear Misrepresentation of the mode by
which the interior heat was transmitted. Tyn-
dali makes an excellent illustration of the
principle for which we have contended, but for
far different purpose. He fills two kettles
with water, and around one of them wraps
moist blanket. lie finds that the water in the
kettle thus surrounded cools much more rapidly
than the other, demonstrating that it has the
better radiation Of the two. Applying this
demonstration to earth, let us consider our
globe kettle of larger proportions--not filled
with warm water, but with incandescent fluid
matter, around three-fourths of which is placed
mot blanket merely an aqueous envelope of
icy GOODNESS at the bottom, with wonderful
powers of radiation at the surface, and we will
then have no difficulty in determining how the
waters OF the ocean have always received their
temperature, and how the interior loses its
heat.-From g The Gulf Stream and the Trade
wind" by William L. Walker, in Harper's
Magazine for April.