rains; but let an inland rise never so little above
the water, and the precipitation upon it becomes
copious. Islands in the South Sea are everlastingly
cloud-capped. The western slopes of
the Patagonian Andes squeeze an immense fall
of rain out of the vapours that are blown upon
them. The latent heat of vapour in the air is a
powerful modifier of climate. It is the latent
heat that is liberated during these rains which
gives to Eastern Patagonia its mild climate.
The aqueous vapour which the air carries along
with it is, to the winds, precisely what coals are
to the steam-ship at sea—the source of motive
power. The condensation of vapour is for one
what the consummation of fuel is with the other;
only, with the winds, the same heat may be used
over and over again, and for many purposes. By
simply sending moist air to the top of snow-
capped mountains, condensing its moisture, and
bringing it down to the surface again, it is made
hot. Though by going up the air be cooled, it
is expanded, and receives as sensible heat the
latent heat of its vapour; being brought down
to the surface again, and compressed by the whole
weight of the barometric column, it is hotter than
it was before by the amount of heat received
from its vapour. We need hardly wonder at the
low range of the barometer or the mildness of
the temperature in all rainy latitudes.

To give some idea of the softened climate
which might arise from this source, let us
imagine the air when it strikes the Antarctic
continent to be charged with vapour at the
temperature of forty degrees. In order to arrive at the
polar calms, suppose it to cross a mountain-range
whose summits reach the region of perpetual
snow. As this air, with its moisture, rises, it
expands, cools, and liberates the latent heat of
its vapour, which the air receives in the sensible
form, sufficiently, say, to raise its temperature
twenty degrees. This air, coming from the sea at
the temperature of forty degrees, loses vapour,
but gains heat. Descending into the valleys
beyond, it is again compressed by the weight of the
barometric column, and its temperature now,
instead of being forty degrees, will be sixty degrees.
There may therefore exist, within the Antarctic
continent, a climate perfectly compatible with
abundant animal and vegetable life. The
topographical feature of the Antarctic regions lend
themselves to such a climate so brought about.

Labrador and the Falkland Islands are in
corresponding latitudes north and south. They are
both on the windward side of the Atlantic; they
occupy relatively the same position with regard
to the wind. Labrador is almost uninhabitable,
on account of the severity of its climate; but
in the Falkland Islands and their neighbouring
shores the cattle find pasturage throughout the
winter. The thermometrical difference of climate
between these two places, north and south, may
be taken as a sort of index to the relative
difference between the Arctic and Antarctic climates
of our planet. Captain Smyley, an American
sealer, planted a self-registering thermometer on
the South Shetlands, south latitude sixty-three
degrees, and left it for several winters, during
which time it went no lower than five degrees
Fahrenheit. Compare this with  the twenty-nine
degrees felt last January, at St Petersburg, in
north latitude sixty degrees.  At Moscow, the
mercury froze in the thermometers.

These facts powerfully plead the cause of
Antarctic exploration. Within the periphery of
that circle is included an area equal in extent
to the one-sixth part of the entire land surface
of our planet. Most of this immense area is
as unknown to the inhabitants of the earth as
is the interior of one of Jupiter's satellites.
What if it should contain a warm, verdant,
habitable oasis, well stocked with animals, birds,
and fish! With steam to aid us and science to
guide us, it would be a reproach to the world
to allow so large a portion of its surface to
remain any longer unexplored. America will do her
part, if she can; for navies are not all for war,
least of all for civil war. And no navy can boast
of brighter chaplets than those which have been
gathered in the fields of geographical research.

To jump at one bound from pole to pole: an
attentive examination of the laws which govern
the movements of the waters in their channels
of circulation in the ocean, leads irresistibly to
the conclusion that, always, in summer and
winter, there must be, somewhere within the
Arctic circle, a large body of open water, which
must impress a curious feature upon the physical
aspects of these regions. The whales had
taught us to suspect the existence of open water
in the Arctic basin, and in their mute way told
of a passage there, at least sometimes. It is
the custom among whalers to have their
harpoons marked with date and the name of the
ship; and Dr. Scoresby mentions several
instances of whales that have been taken near the
Behring's Strait side with harpoons in them
bearing the stamp of ships that were known to
cruise on the Baffin's Bay side of the American
continent. And as, in one or two instances, a
very short time had elapsed between the date of
capture in the Pacific, and the date when the
fish must have been struck on the Atlantic side,
it was argued, therefore, that there was a north-
west passage by which the whales passed from
one side to the other, since the stricken animal
could not have had the harpoon in him long
enough to admit of a passage—even if that were
possible, with his heat-hating constitution—
around either Cape Horn, or the Cape of Good
Hope. We have therefore incontrovertible
circumstantial evidence that there is, at times
at least, open water communication through the
Arctic Sea from one side of the American
continent to the other. But this does not prove
the existence of an open sea there; it only
establishes the existence—occasional if you please—
of a channel through which whales had passed.
Captain Maury offers other evidence to induce
the reader to believe with him in the existence
of an open sea in the Arctic Ocean.

There is an under-current setting in, from the
Atlantic through Davis's Straits, to the Arctic
Ocean; and there is a surface-current setting
out. Now this under-current comes from the