CHAPTER XXIII
THE PROJECTILE-VEHICLE
On the completion of the Columbiad the public interest centeredin the projectile itself, the vehicle which was destined tocarry 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 wasconsequently cast on the 2nd of November, and immediatelyforwarded by the Eastern Railway to Stones Hill, which itreached without accident on the 10th of that month, where MichelArdan, Barbicane, and Nicholl were waiting impatiently for it.
The projectile had now to be filled to the depth of three feetwith a bed of water, intended to support a water-tight woodendisc, which worked easily within the walls of the projectile.It was upon this kind of raft that the travelers were to taketheir place. This body of water was divided by horizontalpartitions, which the shock of the departure would have to breakin succession. Then each sheet of the water, from the lowestto the highest, running off into escape tubes toward the top ofthe projectile, constituted a kind of spring; and the woodendisc, supplied with extremely powerful plugs, could not strikethe lowest plate except after breaking successively thedifferent partitions. Undoubtedly the travelers would stillhave to encounter a violent recoil after the complete escapementof the water; but the first shock would be almost entirelydestroyed by this powerful spring. The upper parts of the wallswere lined with a thick padding of leather, fastened upon springsof the best steel, behind which the escape tubes were completelyconcealed; thus all imaginable precautions had been taken foraverting the first shock; and if they did get crushed, theymust, as Michel Ardan said, be made of very bad materials.
The entrance into this metallic tower was by a narrow aperturecontrived in the wall of the cone. This was hermetically closedby a plate of aluminum, fastened internally by powerfulscrew-pressure. The travelers could therefore quit their prisonat pleasure, as soon as they should reach the moon.
Light and view were given by means of four thick lenticularglass scuttles, two pierced in the circular wall itself, thethird in the bottom, the fourth in the top. These scuttles thenwere protected against the shock of departure by plates let intosolid grooves, which could easily be opened outward byunscrewing them from the inside. Reservoirs firmly fixedcontained water and the necessary provisions; and fireand light were procurable by means of gas, contained in aspecial reservoir under a pressure of several atmospheres.They had only to turn a tap, and for six hours the gas wouldlight and warm this comfortable vehicle.
There now remained only the question of air; for allowing forthe consumption of air by Barbicane, his two companions, and twodogs which he proposed taking with him, it was necessary torenew the air of the projectile. Now air consists principallyof twenty-one parts of oxygen and seventy-nine of nitrogen.The lungs absorb the oxygen, which is indispensable for the supportof life, and reject the nitrogen. The air expired loses nearlyfive per cent. of the former and contains nearly an equal volumeof carbonic acid, produced by the combustion of the elements ofthe blood. In an air-tight enclosure, then, after a certaintime, all the oxygen of the air will be replaced by the carbonicacid-- a gas fatal to life. There were two things to be donethen-- first, to replace the absorbed oxygen; secondly, todestroy the expired carbonic acid; both easy enough to do, bymeans of chlorate of potassium and caustic potash. The formeris a salt which appears under the form of white crystals; whenraised to a temperature of 400 degrees it is transformed intochlorure of potassium, and the oxygen which it contains isentirely liberated. Now twenty-eight pounds of chlorate ofpotassium produces seven pounds of oxygen, or 2,400 litres-- thequantity necessary for the travelers during twenty-four hours.
Caustic potash has a great affinity for carbonic acid; and it issufficient to shake it in order for it to seize upon the acidand form bicarbonate of potassium. By these two means theywould be enabled to restore to the vitiated air its life-supporting properties.
It is necessary, however, to add that the experiments hadhitherto been made _in anima vili_. Whatever its scientificaccuracy was, they were at present ignorant how it would answerwith human beings. The honor of putting it to the proof wasenergetically claimed by J. T. Maston.
"Since I am not to go," said the brave artillerist, "I may atleast live for a week in the projectile."
It would have been hard to refuse him; so they consented tohis wish. A sufficient quantity of chlorate of potassium andof caustic potash was placed at his disposal, together withprovisions for eight days. And having shaken hands with hisfriends, on the 12th of November, at six o'clock A.M., afterstrictly informing them not to open his prison before the 20th,at six o'clock P.M., he slid down the projectile, the plate ofwhich was at once hermetically sealed. What did he do withhimself during that week? They could get no information.The thickness of the walls of the projectile prevented anysound reaching from the inside to the outside. On the 20thof November, at six P.M. exactly, the plate was opened.The friends of J. T. Maston had been all along in a state ofmuch anxiety; but they were promptly reassured on hearing ajolly voice shouting a boisterous hurrah.
Presently afterward the secretary of the Gun Club appeared atthe top of the cone in a triumphant attitude. He had grown fat!