THE PROJECTILE-VEHICLE.
On the completion of the Columbiad the public interest centred in the
projectile itself, the vehicle which was destined to carry the three
hardy adventurers into space.
The new plans had been sent to Breadwill and Co., of Albany, with the
request for their speedy execution. The projectile was consequently cast
on the 2d November, and immediately forwarded by the Eastern Railway to
Stones Hill, which it reached without accident on the 10th of that month,
where Michel Ardan, Barbicane, and Nicholl were waiting impatiently for
it.
The projectile had now to be filled to the depth of three feet with a
bed of water, intended to support a watertight wooden disc, which worked
easily within the walls of the projectile. It was upon this kind of
raft that the travellers were to take their place. This body of water
was divided by horizontal partitions, which the shock of the departure
would have to break in succession. Then each sheet of the water, from
the lowest to the highest, running off into escape tubes toward the top
of the projectile, constituted a kind of spring; and the wooden disc,
supplied with extremely powerful plugs, could not strike the lowest plate
except after breaking successively the different partitions. Undoubtedly
the travellers would still have to encounter a violent _recoil_ after
the complete escapement of the water; but the first shock would be almost
entirely destroyed by this powerful spring. The upper part of the walls
were lined with a thick padding of leather, fastened upon springs of the
best steel, behind which the escape tubes were completely concealed; thus
all imaginable precautions had been taken for averting the first shock;
and if they _did_ get crushed, they must, as Michel Ardan said, be made
of very bad materials.
Illustration: THE ARRIVAL OF THE PROJECTILE AT STONE'S HILL.
The entrance into this metallic tower was by a narrow aperture contrived
in the wall of the cone. This was hermetically closed by a plate of
aluminium, fastened internally by powerful screw-pressure. The travellers
could therefore quit their prison at pleasure, as soon as they should
reach the moon.
Light and view were given by means of four thick lenticular glass
scuttles, two pierced in the circular wall itself, the third in the
bottom, the fourth in the top. These scuttles then were protected against
the shock of departure by plates let into solid grooves, which could
easily be opened outwards by unscrewing them from the inside. Reservoirs
firmly fixed contained water and the necessary provisions; and fire and
light were procurable by means of gas, contained in a special reservoir
under a pressure of several atmospheres. They had only to turn a tap,
and for six hours the gas would light and warm this comfortable vehicle.
There now remained only the question of air; for allowing for the
consumption of air by Barbicane, his two companions, and two dogs which
he proposed taking with him, it was necessary to renew the air of the
projectile. Now air consists principally of twenty-one parts of oxygen
and seventy-nine of nitrogen. The lungs absorb the oxygen, which is
indispensable for the support of life, and reject the nitrogen. The air
expired loses nearly five per cent. of the former and contains nearly an
equal volume of carbonic acid, produced by the combustion of the elements
of the blood. In an air-tight enclosure, then, after a certain time, all
the oxygen of the air will be replaced by the carbonic acid—a gas fatal
to life. There were two things to be done then—first, to replace the
absorbed oxygen; secondly, to destroy the expired carbonic acid; both
easy enough to do, by means of chlorate of potassium and caustic potash.
The former is a salt which appears under the form of white crystals;
when raised to a temperature of 400° it is transformed into chlorate
of potass, and the oxygen which it contains is entirely liberated. Now
twenty-eight pounds of chlorate of potassium produce seven pounds of
oxygen, or 2400 _litres_—the quantity necessary for the travellers
during twenty-four hours.
Caustic potash has a great affinity for carbonic acid; and it is
sufficient to shake it in order for it to seize upon the acid and form
bi-carbonate of potass. By these two means they would be enabled to
restore to the vitiated air its life-supporting properties.
It is necessary, however, to add that the experiments had hitherto been
made _in anima vili_. Whatever its scientific accuracy was, they were at
present ignorant how it would answer with human beings. The honour of
putting it to the proof was energetically claimed by J. T. Maston.
"Since I am not to go," said the brave artillerist, "I may at least live
for a week in the projectile."
It would have been hard to refuse him; so they consented to his wish.
A sufficient quantity of chlorate of potassium and of caustic potash
was placed at his disposal, together with provisions for eight days.
And having shaken hands with his friends, on the 12th November, at six
o'clock a.m., after strictly informing them not to open his prison before
the 20th, at six o'clock p.m., he slid down the projectile, the plate
of which was at once hermetically sealed. What did he do with himself
during that week? They could get no information. The thickness of the
walls of the projectile prevented any sound reaching from the inside
to the outside. On the 20th of November, at six p.m. exactly, the plate
was opened. The friends of J. T. Maston had been all along in a state of
much anxiety; but they were promptly reassured on hearing a jolly voice
shouting a boisterous hurrah.
Presently afterwards the secretary of the Gun Club appeared at the top
of the cone in a triumphant attitude. He had grown fat!
Illustration: J. T. MASTON HAD GROWN FAT.