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  CHAPTER VII.

  THE HYMN OF THE CANNON-BALL.

  The Cambridge Observatory had, in its memorable letter of October 7th,treated the question from an astronomical point of view--the mechanicalpoint had still to be treated. It was then that the practicaldifficulties would have seemed insurmountable to any other country butAmerica; but there they were looked upon as play.

  President Barbicane had, without losing any time, nominated a workingcommittee in the heart of the Gun Club. This committee was in threesittings to elucidate the three great questions of the cannon, theprojectile, and the powder. It was composed of four members very learnedupon these matters. Barbicane had the casting vote, and with him wereassociated General Morgan, Major Elphinstone, and, lastly, theinevitable J.T. Maston, to whom were confided the functions ofsecretary.

  On the 8th of October the committee met at President Barbicane's house,No. 3, Republican-street; as it was important that the stomach shouldnot trouble so important a debate, the four members of the Gun Club tooktheir seats at a table covered with sandwiches and teapots. J.T. Mastonimmediately screwed his pen on to his steel hook and the business began.

  Barbicane opened the meeting as follows:--

  "Dear colleagues," said he, "we have to solve one of the more importantproblems in ballistics--that greatest of sciences which treats of themovement of projectiles--that is to say, of bodies hurled into space bysome power of impulsion and then left to themselves."

  "Oh, ballistics, ballistics!" cried J.T. Maston in a voice of emotion.

  "Perhaps," continued Barbicane, "the most logical thing would be toconsecrate this first meeting to discussing the engine."

  "Certainly," answered General Morgan.

  "Nevertheless," continued Barbicane, "after mature deliberation, itseems to me that the question of the projectile ought to precede that ofthe cannon, and that the dimensions of the latter ought to depend uponthe dimensions of the former."

  J.T. Maston here interrupted the president, and was heard with theattention which his magnificent past career deserved.

  "My dear friends," said he in an inspired tone, "our president is rightto give the question of the projectile the precedence of every other;the cannon-ball we mean to hurl at the moon will be our messenger, ourambassador, and I ask your permission to regard it from an entirelymoral point of view."

  This new way of looking at a projectile excited the curiosity of themembers of the committee; they therefore listened attentively to thewords of J.T. Maston.

  "My dear colleagues," he continued, "I will be brief. I will lay asidethe material projectile--the projectile that kills--in order to take upthe mathematical projectile--the moral projectile. A cannon-ball is tome the most brilliant manifestation of human power, and by creating itman has approached nearest to the Creator!"

  "Hear, hear!" said Major Elphinstone.

  "In fact," cried the orator, "if God has made the stars and the planets,man has made the cannon-ball--that criterion of terrestrial speed--thatreduction of bodies wandering in space which are really nothing butprojectiles. Let Providence claim the speed of electricity, light, thestars, comets, planets, satellites, sound, and wind! But ours is thespeed of the cannon-ball--a hundred times greater than that of trainsand the fastest horses!"

  J.T. Maston was inspired; his accents became quite lyrical as he chantedthe hymn consecrated to the projectile.

  "Would you like figures?" continued he; "here are eloquent ones. Takethe simple 24 pounder; though it moves 80,000 times slower thanelectricity, 64,000 times slower than light, 76 times slower than theearth in her movement of translation round the sun, yet when it leavesthe cannon it goes quicker than sound; it goes at the rate of 14 miles aminute, 840 miles an hour, 20,100 miles a day--that is to say, at thespeed of the points of the equator in the globe's movement of rotation,7,336,500 miles a year. It would therefore take 11 days to get to themoon, 12 years to get to the sun, 360 years to reach Neptune, at thelimits of the solar world. That is what this modest cannon-ball, thework of our hands, can do! What will it be, therefore, when, with twentytimes that speed, we shall hurl it with a rapidity of seven miles asecond? Ah! splendid shot! superb projectile! I like to think you willbe received up there with the honours due to a terrestrial ambassador!"

  Cheers greeted this brilliant peroration, and J.T. Maston, overcome withemotion, sat down amidst the felicitations of his colleagues.

  "And now," said Barbicane, "that we have given some time to poetry, letus proceed to facts."

  "We are ready," answered the members of the committee as they eachdemolished half-a-dozen sandwiches.

  "You know what problem it is we have to solve," continued the president;"it is that of endowing a projectile with a speed of 12,000 yards persecond. I have every reason to believe that we shall succeed, but atpresent let us see what speeds we have already obtained; General Morgancan edify us upon that subject."

  "So much the more easily," answered the general, "because during the warI was a member of the Experiment Commission. The 100-pound cannon ofDahlgren, with a range of 5,000 yards, gave their projectiles an initialspeed of 500 yards a second."

  "Yes; and the Rodman Columbiad?" (the Americans gave the name of"Columbiad" to their enormous engines of destruction) asked thepresident.

  "The Rodman Columbiad, tried at Fort Hamilton, near New York, hurled aprojectile, weighing half a ton, a distance of six miles, with a speedof 800 yards a second, a result which neither Armstrong nor Palliser hasobtained in England."

  "Englishmen are nowhere!" said J.T. Maston, pointing his formidablesteel hook eastward.

  "Then," resumed Barbicane, "a speed of 800 yards is the maximum obtainedat present."

  "Yes," answered Morgan.

  "I might add, however," replied J.T. Maston, "that if my mortar had notbeen blown up--"

  "Yes, but it was blown up," replied Barbicane with a benevolent gesture."We must take the speed of 800 yards for a starting point. We must keeptill another meeting the discussion of the means used to produce thisspeed; allow me to call your attention to the dimensions which ourprojectile must have. Of course it must be something very different toone of half a ton weight."

  "Why?" asked the major.

  "Because," quickly answered J.T. Maston, "it must be large enough toattract the attention of the inhabitants of the moon, supposing thereare any."

  "Yes," answered Barbicane, "and for another reason still moreimportant."

  "What do you mean, Barbicane?" asked the major.

  "I mean that it is not enough to send up a projectile and then to thinkno more about it; we must follow it in its transit."

  "What?" said the general, slightly surprised at the proposition.

  "Certainly," replied Barbicane, like a man who knew what he was saying,"or our experiment will be without result."

  "But then," replied the major, "you will have to give the projectileenormous dimensions."

  "No. Please grant me your attention. You know that optical instrumentshave acquired great perfection; certain telescopes increase objects sixthousand, and bring the moon to within a distance of forty miles. Now atthat distance objects sixty feet square are perfectly visible. The powerof penetration of the telescope has not been increased, because thatpower is only exercised to the detriment of their clearness, and themoon, which is only a reflecting mirror, does not send a light intenseenough for the telescopes to increase objects beyond that limit."

  "Very well, then, what do you mean to do?" asked the general. "Do youintend giving a diameter of sixty feet to your projectile?"

  "No."

  "You are not going to take upon yourself the task of making the moonmore luminous?"

  "I am, though."

  "That's rather strong!" exclaimed Maston.

  "Yes, but simple," answered Barbicane. "If I succeed in lessening thedensity of the atmosphere which the moon's light traverses, shall I notrender that light more intense?"

  "Evidently."

  "In order to obtain tha
t result I shall only have to establish mytelescope upon some high mountain. We can do that."

  "I give in," answered the major; "you have such a way of simplifyingthings! What enlargement do you hope to obtain thus?"

  "One of 48,000 times, which will bring the moon within five miles only,and objects will only need a diameter of nine feet."

  "Perfect!" exclaimed J.T. Maston; "then our projectile will have adiameter of nine feet?"

  "Precisely."

  "Allow me to inform you, however," returned Major Elphinstone, "that itsweight will still be--"

  "Oh, major!" answered Barbicane, "before discussing its weight allow meto tell you that our forefathers did marvels in that way. Far be it fromme to pretend that ballistics have not progressed, but it is well toknow that in the Middle Ages surprising results were obtained, I dareaffirm, even more surprising than ours."

  "Justify your statement," exclaimed J.T. Maston.

  "Nothing is easier," answered Barbicane; "I can give you some examples.At the siege of Constantinople by Mahomet II., in 1453, they hurledstone bullets that weighed 1,900 lbs.; at Malta, in the time of itsknights, a certain cannon of Fort Saint Elme hurled projectiles weighing2,500 lbs. According to a French historian, under Louis XI. a mortarhurled a bomb of 500 lbs. only; but that bomb, fired at the Bastille, aplace where mad men imprisoned wise ones, fell at Charenton, where wisemen imprison mad ones."

  "Very well," said J.T. Maston.

  "Since, what have we seen, after all? The Armstrong cannons hurlprojectiles of 500 lbs., and the Rodman Columbiads projectiles of half aton! It seems, then, that if projectiles have increased in range theyhave lost in weight. Now, if we turn our efforts in that direction, wemust succeed with the progress of the science in doubling the weight ofthe projectiles of Mahomet II. and the Knights of Malta."

  "That is evident," answered the major; "but what metal do you intend toemploy for your own projectile?"

  "Simply cast-iron," said General Morgan.

  "Cast-iron!" exclaimed J.T. Maston disdainfully, "that's very common fora bullet destined to go to the moon."

  "Do not let us exaggerate, my honourable friend," answered Morgan;"cast-iron will be sufficient."

  "Then," replied Major Elphinstone, "as the weight of the projectile isin proportion to its volume, a cast-iron bullet, measuring nine feet indiameter, will still be frightfully heavy."

  "Yes, if it be solid, but not if it be hollow," said Barbicane.

  "Hollow!--then it will be an obus?"

  "In which we can put despatches," replied J.T. Maston, "and specimens ofour terrestrial productions."

  "Yes, an obus," answered Barbicane; "that is what it must be; a solidbullet of 108 inches would weigh more than 200,000 lbs., a weightevidently too great; however, as it is necessary to give the projectilea certain stability, I propose to give it a weight of 20,000 lbs."

  "What will be the thickness of the metal?" asked the major.

  "If we follow the usual proportions," replied Morgan, "a diameter of 800inches demands sides two feet thick at least."

  "That would be much too thick," answered Barbicane; "we do not want aprojectile to pierce armour-plate; it only needs sides strong enough toresist the pressure of the powder-gas. This, therefore, is theproblem:--What thickness ought an iron obus to have in order to weighonly 20,000 lbs.? Our clever calculator, Mr. Maston, will tell us atonce."

  "Nothing is easier," replied the honourable secretary.

  So saying, he traced some algebraical signs on the paper, amongst whichn^2 and x^2 frequently appeared. He even seemed to extract from them acertain cubic root, and said--

  "The sides must be hardly two inches thick."

  "Will that be sufficient?" asked the major doubtfully.

  "No," answered the president, "certainly not."

  "Then what must be done?" resumed Elphinstone, looking puzzled.

  "We must use another metal instead of cast-iron."

  "Brass?" suggested Morgan.

  "No; that is too heavy too, and I have something better than that topropose."

  "What?" asked the major.

  "Aluminium," answered Barbicane.

  "Aluminium!" cried all the three colleagues of the president.

  "Certainly, my friends. You know that an illustrious French chemist,Henry St. Claire Deville, succeeded in 1854 in obtaining aluminium in acompact mass. This precious metal possesses the whiteness of silver, theindestructibility of gold, the tenacity of iron, the fusibility ofcopper, the lightness of glass; it is easily wrought, and is very widelydistributed in nature, as aluminium forms the basis of most rocks; it isthree times lighter than iron, and seems to have been created expresslyto furnish us with the material for our projectile!"

  "Hurrah for aluminium!" cried the secretary, always very noisy in hismoments of enthusiasm.

  "But, my dear president," said the major, "is not aluminium quotedexceedingly high?"

  "It was so," answered Barbicane; "when first discovered a pound ofaluminium cost 260 to 280 dollars; then it fell to twenty-seven dollars,and now it is worth nine dollars."

  "But nine dollars a pound," replied the major, who did not easily givein; "that is still an enormous price."

  "Doubtless, my dear major; but not out of reach."

  "What will the projectile weigh, then?" asked Morgan.

  "Here is the result of my calculations," answered Barbicane. "Aprojectile of 108 inches in diameter and 12 inches thick would weigh, ifit were made of cast-iron, 67,440 lbs.; cast in aluminium it would bereduced to 19,250 lbs."

  "Perfect!" cried Maston; "that suits our programme capitally."

  "Yes," replied the major; "but do you not know that at nine dollars apound the projectile would cost--"

  "One hundred seventy-three thousand and fifty dollars. Yes, I know that;but fear nothing, my friends; money for our enterprise will not bewanting, I answer for that."

  "It will be showered upon us," replied J.T. Maston.

  "Well, what do you say to aluminium?" asked the president.

  "Adopted," answered the three members of the committee.

  "As to the form of the projectile," resumed Barbicane, "it is of littleconsequence, since, once the atmosphere cleared, it will find itself inempty space; I therefore propose a round ball, which will turn onitself, if it so pleases."

  Thus ended the first committee meeting. The question of the projectilewas definitely resolved upon, and J.T. Maston was delighted with theidea of sending an aluminium bullet to the Selenites, "as it will givethem no end of an idea of the inhabitants of the earth!"