a time when steam had not yet been applied
to locomotive purposes, and while railways
were still unknown. Even at the present
day, and with the knowledge of the great
rapidity which locomotion has attained,
many persons are alarmed at the idea of
having to spend half-an-hour, or an hour,
underground: which would be the time
required to cross the Channel in a tunnel at
its narrowest point. But think of what would
have been the length of the subterranean
journey proposed by Mathieu in eighteen
hundred and two, when the only means of
transport known, were carriages drawn by
horses! At that rate, the notion was to
construct, beneath the bed of the sea, a
paved road, like the old ordinary French pavés,
which should be worked by diligences and
lighted by lamps: the distance (some twenty
miles or more) which would now be traversed
in half-an-hour, would then have taken four
or five hours to accomplish! During that
long space of time, what would have been the
condition of the lady and gentlemen passengers
who complain of the difficulty of breathing
in long railway-tunnels like that of Rollebrise,
or that of La Nerthe, on the railway
between Marseilles and Avignon?

To ventilate his tunnel, Matthieu proposed
the establishment of a series of chimneys in
the open sea. By machinery similar to that
which serves for the unlading of cannon
from a ship of the line, he proposed to sink
hollow columns, composed of very heavy
cast-iron rings, bringing and depositing them
section by section, so as to form these chimneys,
which should be firmly maintained in
their place by their own proper weight, and
which were to have their base consolidated
by rock-work sunk around their foot. These
columns were to serve as points of attack in
the excavation of the tunnel, as well as for
the supply of atmospheric air. Constructions
like these, in the midst of a large expanse of
water, might be possible where the depth
was shallow, as in a lake where no current
existed; but they would become impracticable
with great depth of soundings or with an
exposure to strong tides and violent tempests.

During the last few months, the project of
a submarine tunnel from France to England
has been again brought before the public by
Monsieur Thomé de Gamond; and what is
more, the present Emperor, to whom it has
been submitted, regards it both as desirable
and practicable. By his order, it has been
examined by a commission of civil engineers
attached to the government, all men of
eminence. This commission, after mature
consideration, is of opinion that the plan is
practicable, and deserves to be seriously
entertained. The members have
recommended the government to lay out five
hundred thousand francs, or twenty thousand
pounds, in making new investigations of the
subject, and have also suggested that the
English government be applied to, to know
whether it feels disposed to associate itself
with this further investigation.

The line adopted by Monsieur Thomé
leaves the continent from below Cape Grinez
(where stands the lighthouse visible from
the English coast) between Boulogne and
Calais; it passes beneath a shoal called the
bank of Varne, and reaches England at Eastware,
between Folkestone and Dover. These
two points are attained—in France by a
subterranean road nine kilometres long (four
kilometres make a French league, or two and
a half miles English), starting from Marquise,
and taking earth at the neighbouring village
Bazinghen, and sloping down towards Cape
Grinez, where it reaches the submarine
tunnel under a tower open to the sky at top;
and, in England, by a tunnel five kilometres
and a-half long, starting from Dover, and
likewise joining the tunnel in the midst of an
open tower, at Eastware. On the French
side, the Marquise tunnel would be connected
with the Northern Railway by two branch
lines to Calais and Boulogne. The line of
the tunnel itself describes a concave subterranean
curve whose inclines (which never
have a slope of five in a thousand) are much
more gentle than those of many railways.
The total length of the underground road
will be forty-seven kilometres, thirty-four of
which are beneath the sea. Many travellers
who would calmly traverse a tunnel on land,
or even the Thames Tunnel, might feel
alarmed for their own safety in a
submarine tunnel. It is doubtful even, whether
the opening train would be very numerously
filled, however splendid a déjeûner might be
offered by the directors to their guests. But
the mishaps which attended the piercing of
the Thames Tunnel are much less to be
apprehended in the Channel undertaking.
Brunel went within four feet of the bed of
the Thames; one fine day, the thin stratum
gave way and completely flooded him. He
was obliged to make an artificial river's-bed
by throwing in bags of clay over the leaky
spot, to enable him to pump out the water.
But, the Channel tunnel will be separated
from the sea by a solid roof whose thickness
varies from twenty-two to eighty
metres (which are considerably longer than
yards), and will be protected by a natural
shield of rock. Monsieur Thomé has the
greater claim to be heard, because he has
made a careful geological study of his ground.

The excavation of such a tunnel may be
considered as the direction of the gallery of a
mine through the bed of the ocean; the
inventor of the scheme arrives, consequently,
at the obvious method of assimilating his
points of attack out at sea to points of attack
situated on dry land. For this purpose, he
proposes to found in the Channel a series of
little rocky islets, which shall rise above
high water mark, and on which he will
establish buildings and machinery to sink
the shafts of the mine into the solid earth.