themselves, too, it must be remembered, were
in the first instance built by little members
of the vast and industrious community
which swarms within the crystal palace of
the sea.

An argument to the stomach is at all times
so satisfactory, that one has only to remind
the rich of callipash and callipee as sea-begotten:
to allude to turbot, one has only to
suggest to humbler appetites,

"The periwinkle, prawn, the cockle and the
shrimp."

One has only to say to the collective hunger
of the nation "Oyster! lobster!" and at once
the sea is acknowledged to be, not a desert, but
appears green and refreshing in all eyes, and
will bear description as a highly valuable
tract of pasture-ground. We were in the
neighbourhood of Australia just now. As we
are on the way, perhaps you will not object to
step down to the South Pole for a minute,
or at least to the vicinity of the great Southern
Continent, visited lately by our Phantom Ship.
Cold water is to be found in perfection near
that great refrigerator, and from thence it
flows in a vast ocean river towards the Equator.
Now, starting from the icy shores of South
Victoria, let us, like good, quiet beings, travel
with the stream.

What causes the stream, though? That is
soon told. Water at the Poles is cold enough
to ice champagne, and at the Equator it is
nearly warm enough for shaving. Water
expands when warmed; our pots boil over; and
although the ocean certainly is nowhere hot
enough to boil a leg of mutton, the great
mass of water rises under influence of tropic
heat above the common level, and runs over
towards the Poles, leaving its place empty for
cold water to rush in and occupy. Precisely
in the same way, air, which is another ocean,
swells at the Equator, and pours out its deluge
north and south over the colder current which
runs in to take advantage of the vacancy, and
warm itself. When warm, it also will get up.
That is one fact: another modifies it. The
earth rolls on its axis. If you stick a knitting-
needle through the centre of an orange, and
rotate the orange on the needle, then you see
a model of the earth rotating on its axis. The
needle comes out of the north pole above, and
out of the south pole below; and, if you
scratch a line all round the orange, half-way
between pole and pole, that is the imagined
line called the equator. Now, take two little
pins; stick one of them on the equator, and
another in the neighbourhood of either pole;
set the orange now revolving like the globe
itself, from west to east, and make precisely
one revolution. In the same space of time
one pin has travelled through a great space,
you perceive; all round the orange, as it were:
while the pin near the pole has had a very
tiny journey to perform, and on the pole itself
would absolutely not revolve at all. So, then,
upon this world of ours, everything on or
near the Equator, spins round in the twenty-
four hours far more rapidly than anything
placed near the Poles. But everything
partakes in the movement; as you share in your
body the movement of a railway train, let
the train stop suddenly, your body travels on
and throws you violently forward. So air
and water, flowing from the Equator in great
currents, because they cannot at once
accommodate themselves to the slower movement of
the earth as they approach the Poles, retain
their go-ahead propensity, and shoot on
eastward still, as well as north and south. The
slow trains coming up from the Poles are
outstripped by the rapid movement of the earth
below, and, being unable to accommodate
themselves to it readily, they lag behind and
fall into a westward course. By this
movement of the earth, therefore, a transverse
direction is communicated to the great
equatorial and polar currents, whether of air or
of water. Furthermore, local peculiarities,
arrangements of islands and continents, plain
and mountain, land and water, cause local
variations of temperature, and every such
variation modifies or makes a current. In
the air, we all know how many shiftings of
the wind will be peculiar to a mountain
hamlet, where a lake, a valley, and a mountain
cause a constant oscillation, and a sudden
burst of sunshine is enough to raise the wind.
Mechanical obstructions, such as mountain
peaks in the bed of the great ocean of air,
modify its streams, of course; and the great
currents in the world of water are, of course,
split, deflected, and directed on their way, by
all the continents and islands about and
around which they flow.

Great currents pour like mighty rivers
through the plain of ocean, and fixed by the
laws of nature, though their banks be banks
of water, they are almost as sharply defined
as if they were of granite masonry. These
are constant; there are others periodical,
occasioned by periodical winds, tides, &c.;
and there are also variable currents caused
by melting ice, and other accidents, irregular
in their occurrence.

Now let us follow the great stream of cold
water flowing from the South Pole, called the
Antarctic drift current. From the great
barrier of ice and the Antarctic volcano,
Mount Erebus, it pours up the Pacific, first
in a north-north-easterly direction, then north-
east, then more decidedly towards the east,
partly, perhaps, deflected into this course by
the land of South Victoria; eastward, at any
rate, it flows in a salt-water river of enormous
breadth, and strikes the Pacific coast of South
America, wearing its side into that hollow
shape which you may notice on the map.
The obstruction of the South American
continent splits this great current into two parts,
one of which turns southward, washing round
Cape Horn; the Cape Horn current, which
escapes into the Atlantic Ocean;—the other,
the Peruvian, or Humboldt's current, is