It is a prevalent idea amongst those inhabiting
the shores of the north polar sea, and of others
who have studied the accounts of navigators at
various periods, that there is a gradual elevation
going on in the vicinity of the north pole, tending
to increase the quantity of ice, dimmish the
moisture and temperature of the winds, and thus
gradually lower and deteriorate the climate of
the north temperate zone. Large quantities of
drift wood, at levels which the sea now never
reaches, and sea channels marked in old maps,
where now no channel exists, are amongst the
grounds for this opinion, but the tidal and other
currents are so irregular, and often so considerable
in these waters, that it is not safe to assume
this cause without further evidence.

The barrier of ice that prevents research, and
even in some cases by locking up ships
endeavouring to enter the northern channels, and
carrying them south with the current, induces a
retrograde motion of hundreds of miles, is a far
more variable and serious impediment in arctic
than antarctic water. In both, however, the ice
exists in all its various forms, sometimes as huge
bergs or mountains broken off from glaciers,
sometimes as floes and pack-ice and belts of ice
originally joining on to the land, but broken off
from time to time and drifting with the currents
into the Atlantic, and sometimes as recently-
formed ice in open water. The natural drifts
to the south is greatly but singularly assisted
by the northerly winds which prevail in Baffin's
Bay and Davis's Straits in the summer months of
the year. Those hard westerly gales, accompanied
by abundant cold rain and even hail,
occasionally blowing in the waters round our
own islands and across England, indicated by a
great depression of the mercury both in the
barometer and thermometer, are derived from
the unfavourable state of the season within the
arctic circle, and offer poor promise of fine
weather in our climate when prevailing in the
early part of the year near the vernal equinox.

The extreme cold of the polar regions of the
earth is a subject which has long attracted
general attention, and is certainly very remarkable
during the long cloudless night of winter, when
the radiation into space continues without
interruption. But there is scarcely any part of
the land within the arctic circle where the heat
of the summer sun is not sufficient to admit not
only of a melting of the snow down to the
earth's surface, but also to promote a vegetation
more or less abundant. Everywhere in arctic
America and Siberia the trees freeze to their
centres in winter, and are not thawed till the
end of March or beginning of April, but a few
weeks suffices to develop the various plants for
flowering as well as to cause the leaves to show
themselves on the thawed trees. The winter
frost, however, penetrates far deeper than the
summer thaw, for we are told of places in Siberia
where the frozen soil is penetrated nearly
four hundred feet before water is obtained in a
fluid state, while the ice is obtained under the
summer coating of vegetation at a depth of
three or four feet at the most. Within the
antarctic circle the conditions are so much more
severe than in the arctic, that no vegetation
whatever seems able to exist, not even lichens
growing on the cliffs, even when the snow cannot
lie on them owing to their steepness. Birds,
however, there are, and therefore no doubt there
are also plenty of fish, while the most minute
forms of life such as abound in the deep water
of the Atlantic have been found living in the ice
itself in latitude 78° S, although the temperature
there never rises much above the freezing
point of water, and constantly descends very far
indeed below the zero of .Fahrenheit's thermometer,
remaining there a long time without change.

The arctic quadrupeds form a noble group,
strangely contrasting in number, magnitude, and
variety, with the total absence of quadrupeds in
the lands far south. The useful rein-deer, the
gigantic musk-ox, the great white bear, and the
argali of the Rocky Mountains, are all really
important quadrupeds and belong to the arctic
circle, frequenting the most northerly lands that
man has yet reached. The rein-deer retires
during the extreme cold of winter to the nearest
woods, which again they leave in May for the sea.
They belong to the whole range of extreme
northern land, and are much more widely spread
than the musk oxen. Like the rein-deer, these
latter animals must be regarded as having lived
through a long geological period, and they serve
to connect the period when the elephant and
rhinoceros inhabited the northernmost European
and Asiatic lands with the present time, although
these latter tribes have now receded almost to
the tropics. Seals, walruses, and whales are
common in most of the shores of arctic land, and,
like the white bear, wander far out on the ice.
In case of need they are independent, and can
all remain and find food for a long time without
approaching land. Incredible multitudes of
birds are found in almost every rocky island
throughout the polar regions, both north and
south, and most of them migrate to lands somewhat
warmer for breeding purposes. There are,
indeed, in the north, some land birds, such as the
ptarmigan, the raven, and the snowy owl, but
they are not so abundant, and are not at all
represented at the opposite pole. Pish are incredibly
plentiful; herrings, the white fish, and
a kind of salmon haunting the sea, and trout of
various kinds the fresh waters. The sturgeon
also is well known.

No part of the natural history of the polar
regions is more curious or interesting than that
which relates to their geological structure, and
the kind of fossils or organic remains found in
the rocks. It requires, indeed, no slight effort
to shake off the impression that polar land must
at all times and under all conditions have
partaken of that barren and unfriendly character
which we fancy it now exhibiting; it is so difficult
to realise the possibility of conditions under
which a reasonably high temperature and a
tolerably equable climate should have
characterised these districts, that when geology points
to such conditions as having obtained in former
times, we are naturally cautious in admitting