were unlike the Arctic in respect to their
rigour. Within the Antarctic Circle, the winds
bring air which has swept over water for
hundreds of leagues in all directions. Now, the
aqueous vapour which the air carries with it, is
one of the most powerful modifiers of climate
known. 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. Although, by going up,
the air be cooled, it is at the same time
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 have only to suppose that air, charged
with vapour, has to cross, before arriving at
the place of Polar calms, an Antarctic mountain
range, whose summits are pushed up high into
the regions of perpetual snows—and we can
easily conceive the modifications of climate that
would thence ensue. The Antarctic climate
must be comparatively mild. Therefore, pleads
Maury enthusiastically, Antarctic exploration
merits favourable consideration among all
nations.

An expedition is being prepared which
will not be content, it says, with the
shortcomings of Parry, Franklin, and the rest, but
which sets out with the determination of reaching
the Pole itself, and of not being satisfied
until it gets there. It will start, under the
patronage of the Paris Geographical Society, as
soon as the necessary funds have been subscribed
—towards which the Emperor of the French
has already contributed the handsome sum of
two thousand pounds.

The author of the project, M. Gustave
Lambert, a French hydrographer trained in
the Polytechnic School, expects to solve the
problem by taking the route of Behring's
Strait (the sea-channel which separates Asia
from America), instead of proceeding, like most
other Arctic explorers, by Davis's Strait and
Baffin's Bay. For this he gives his reasons in
a lucid pamphlet, "La Question du Pôle Nord."
Moreover, M. Lambert's conviction of the
possibility of reaching the North Pole is based
neither on a caprice of imagination, which has
made the wish the father to the thought, nor on
a scheme worked out in his study, but by a
laborious examination on the spot, of the routes
by which the Pole may be arrived at.

He regards the matter in hand under two
distinct aspects: first, there is the scientific
question; secondly, the practical question.

At the outset, it is impossible to neglect
certain considerations touching the temperature
of the Polar regions, although they may be
called pure theory. An Italian geometer—the
late Signer Pland—made calculations which are
looked up to as authority. M. Lambert, not
being able to consult them, investigated the
matter for himself, with what he considers
complete success. He has determined, he says, the
simple laws which govern "insolation," or the
quantity of heat thrown by the sun upon different
spots of the globe in different latitudes at
different hours of the day and in different seasons.
Without entering into technical details, a few
of the most striking conclusions may be
mentioned.

The "power or degree of insolation" at any
spot, at a given moment, depends on the angle
formed by a vertical line at that spot with a
line drawn from it to the sun. This angle is
called the zenithal distance. The "power of
insolation," however, must not be confounded
with the thermometrical effect which is its
consequence, but whose intensity depends on a
number of other causes—on the nature, for
instance, of the atmospheric stratum which
envelops the earth like a mantle of down.

The integral calculus enabled M. Lambert to
find the mean power of insolation for every day.
After long wanderings in an algebraic labyrinth,
he discovered simple rules, giving him sets of
figures, a glance at which shows that they
explain themselves, rendering all commentary
needless. A few of the facts the figures tell
us are these;

Towards the 22nd of June—the time of the
summer solstice—the power of insolation is
greater and greater as we proceed from the
Arctic Circle up to the Pole, where it is noon
all day long. The importance of this fact will
become apparent when we remember that, at
that time of the year, the sun throws as much
heat on the North Pole as on places situated in
the latitudes of 59 degrees north and 25 degrees
south: that is to say, as much as on Stockholm
and Christiania in the northern hemisphere, and
on the Canary Islands in the southern, at the
same time of year. That calculation, however,
does not imply that the midsummer temperature
of the North Pole is the same as the temperature
at 59 degrees north and 25 degrees south at the
same date; because in the latter cases a great
amount of heat has been already stored.
Travellers will tell you something about the summer
temperature of Stockholm and the winter climate
of Teneriffe. It is not supposed that the Polar
climate at any season resembles them. But the
figures are unquestionably curious and significant.

About the 22nd of May and the 22nd of July
the degrees of insolation, equal to that of the
Pole, are found at 66 degrees north and 33
degrees south: say in an Iceland summer and a
Cape of Good Hope winter. About the 22nd
of April and the 22nd of August they are 78
degrees north and 57 degrees south, corresponding
to a Spitzbergen summer and a Cape Horn
winter. Finally, at the equinoxes, about the
22nd of March and the 22nd of September, the
North Pole receives no heat. On the contrary,
it loses by radiation that which it had absorbed
during the summer months. These figures,
however, are held to prove that the Polar Sea is not
constantly covered with a coating of perennial
ice, but that, during the sunshiny season, it is
possible for ships to navigate it.

In 1827, Captain Parry and Lieutenant Ross,