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CHAPTER IX.
THE QUESTION OF THE POWDERS
There remained for consideration merely the question of powders. The public awaited with interest its final decision. The size of the projectile, the length of the cannon being settled, what would be the quantity of powder necessary to produce impulsion?
It is generally asserted that gunpowder was invented in the fourteenth century by the monk Schwartz, who paid for his grand discovery with his life. It is, however, pretty well proved that this story ought to be ranked amongst the legends of the middle ages. Gunpowder was not invented by any one; it was the lineal successor of the Greek fire, which, like itself, was composed of sulphur and saltpetre. Few persons are acquainted with the mechanical power of gunpowder. Now this is precisely what is necessary to be understood in order to comprehend the importance of the question submitted to the committee.
A litre of gunpowder weighs about 2 lbs.; during combustion it produces 400 litres of gas. This gas, on being liberated and acted upon by a temperature raised to 2400 degrees, occupies a space of 4000 litres: consequently the volume of powder is to the volume of gas produced by its combustion as 1 to 4000. One may judge, therefore, of the tremendous pressure of this gas when compressed within a space 4000 times too confined. All this was, of course, well known to the members of the committee when they met on the following evening.
The first speaker on this occasion was Major Elphinstone, who had been the director of the gunpowder factories during the war.
"Gentlemen," said this distinguished chemist, "I begin with some figures which will serve as the basis of our calculation. The old 24-pounder shot required for its discharge 16 lbs. of powder."
"You are certain of the amount?" broke in Barbicane.
"Quite certain," replied the major. "The Armstrong cannon employs only 75 lbs. of powder for a projectile of 800 lbs., and the Rodman Columbiad uses only 160 lbs. of powder to send its half-ton shot a distance of six miles. These facts cannot be called in question, for I myself raised the point during the depositions taken before the Committee of Artillery."
"Quite true," said the general.
"Well," replied the major, "these figures go to prove that the quantity of powder is not increased with the weight of the shot; that is to say, if a 24-pounder shot requires 16 lbs. of powder; – in other words, if in ordinary guns we employ a quantity of powder equal to two-thirds of the weight of the projectile, this proportion is not constant. Calculate, and you will see that in place of 333 lbs. of powder, the quantity is reduced to no more than 160 lbs."
"What are you aiming at?" asked the president.
"If you push your theory to extremes, my dear major," said J. T. Maston, "you will get to this, that as soon as your shot becomes sufficiently heavy you will not require any powder at all."
"Our friend Maston is always at his jokes, even in serious matters," cried the major; "but let him make his mind easy, I am going presently to propose gunpowder enough to satisfy his artillerist's propensities. I only keep to statistical facts when I say that during the war, and for the very largest guns, the weight of powder was reduced, as the result of experience, to a tenth part of the weight of the shot."
"Perfectly correct," said Morgan; "but before deciding the quantity of powder necessary to give the impulse, I think it would be as well – "
"We shall have to employ a large-grained powder," continued the major, "its combustion is more rapid than that of the small."
"No doubt about that," replied Morgan, "but it is very destructive, and ends by enlarging the bore of the pieces."
"Granted; but that which is injurious to a gun destined to perform long service is not so to our Columbiad. We shall run no danger of an explosion; and it is necessary that our powder should take fire instantaneously in order that its mechanical effect may be complete."
"We must have," said Maston, "several touch-holes, so as to fire it at different points at the same time."
"Certainly," replied Elphinstone; "but that will render the working of the piece more difficult. I return then to my large-grained powder, which removes those difficulties. In his Columbiad charges Rodman employed a powder as large as chestnuts, made of willow charcoal, simply dried in cast-iron pans. This powder was hard and glittering, left no trace upon the hand, contained hydrogen and oxygen in large proportion, took fire instantaneously, and, though very destructive, did not sensibly injure the mouth-piece."
Up to this point Barbicane had kept aloof from the discussion; he left the others to speak while he himself listened; he had evidently got an idea. He now simply said, "Well, my friends, what quantity of powder do you propose?"
The three members look at one another.
"Two hundred thousand pounds," at last said Morgan.
"Five hundred thousand," added the major.
"Eight hundred thousand," screamed Maston.
A moment of silence followed this triple proposal; it was at last broken by the president.
"Gentlemen," he quietly said, "I start from this principle, that the resistance of a gun, constructed under the given conditions, is unlimited. I shall surprise our friend Maston, then, by stigmatizing his calculations as timid; and I propose to double his 800,000 lbs. of powder."
"Sixteen hundred thousand pounds?" shouted Maston, leaping from his seat.
"Just so."
"We shall have to come then to my ideal of a cannon half a mile long; for you see 1,600,000 lbs. will occupy a space of about 20,000 cubic feet; and since the contents of your cannon do not exceed 54,000 cubic feet, it would be half full; and the bore will not be more than long enough for the gas to communicate to the projectile sufficient impulse."
"Nevertheless," said the president, "I hold to that quantity of powder. Now, 1,600,000 lbs. of powder will create 6,000,000,000 of litres of gas. Six thousand millions! You quite understand?"
"What is to be done then?" said the general.
"The thing is very simple; we must reduce this enormous quantity of powder, while preserving to it its mechanical power."
"Good; but by what means?"
"I am going to tell you," replied Barbicane quietly. "Nothing is more easy than to reduce this mass to one quarter of its bulk. You know that curious cellular matter which constitutes the elementary tissues of vegetables? This substance is found quite pure in many bodies, especially in cotton, which is nothing more than the down of the seeds of the cotton plant. Now cotton, combined with cold nitric acid, becomes transformed into a substance eminently insoluble, combustible, and explosive. It was first discovered in 1832, by Braconnot, a French chemist, who called it xyloidine. In 1838 another Frenchman, Pelouze, investigated its different properties, and finally, in 1846, Schonbein, Professor of Chemistry at Bâle, proposed its employment for purposes of war. This powder, now called pyroxyle, or fulminating cotton, is prepared with great facility by simply plunging cotton for fifteen minutes in nitric acid, then washing it in water, then drying it, and it is ready for use."
"Nothing could be more simple," said Morgan.
"Moreover, pyroxyle is unaltered by moisture – a valuable property to us, inasmuch as it would take several days to charge the cannon. It ignites at 170 degrees in place of 240, and its combustion is so rapid that one may set light to it on the top of ordinary powder, without the latter having time to ignite."
"Perfect!" exclaimed the major.
"Only it is more expensive."
"What matter?" cried J. T. Maston.
"Finally, it imparts to projectiles a velocity four times superior to that of gunpowder. I will even add, that if we mix with it one-eighth of its own weight of nitrate of potass, its expansive force is again considerably augmented."
"Will that be necessary?" asked the major.
"I think not," replied Barbicane. "So, then, in place of 1,600,000 lbs. of powder, we shall have but 400,000 lbs. of fulminating cotton; and since we can, without danger, compress 500 lbs. of cotton into 27 cubic feet, the whole quantity will not occupy a height of more than 180 feet within the bore of the Columbiad. In this way the shot will have more than 700 feet of bore to traverse under a force of 6,000,000,000 litres of gas before taking its flight towards the moon."
At this junction J. T. Maston could not repress his emotion; he flung himself into the arms of his friend with the violence of a projectile, and Barbicane would have been stove in if he had not been bomb-proof.
This incident terminated the third meeting of the Committee.
Barbicane and his bold colleagues, to whom nothing seemed impossible, had succeeded in solving the complex problems of projectile, cannon, and powder. Their plan was drawn up, and it only remained to put it in execution.
"A mere matter of detail, a bagatelle," said J. T. Maston.
CHAPTER X.
ONE ENEMY v. TWENTY-FIVE MILLIONS OF FRIENDS
The American public took a lively interest in the smallest details of the enterprise of the Gun Club. It followed day by day the discussions of the committee. The most simple preparation for the great experiment, the questions of figures which it involved, the mechanical difficulties to be resolved – in one word, the entire plan of work – roused the popular excitement to the highest pitch.
The purely scientific attraction was suddenly intensified by the following incident: —
We have seen what legions of admirers and friends Barbicane's project had rallied round its author. There was, however, one single individual alone in all the States of the Union who protested against the attempt of the Gun Club. He attacked it furiously on every opportunity, and human nature is such that Barbicane felt more keenly the opposition of that one man than he did the applause of all the others. He was well aware of the motive of this antipathy, the origin of this solitary enmity, the cause of its personality and old standing, and in what rivalry of self-love it had its rise.
This persevering enemy the President of the Gun Club had never seen. Fortunate that it was so, for a meeting between the two men would certainly have been attended with serious consequences. This rival was a man of science, like Barbicane himself, of a fiery, daring, and violent disposition; a pure Yankee. His name was Captain Nicholl; he lived at Philadelphia.
Most people are aware of the curious struggle which arose during the Federal war between the guns and the armour of iron-plated ships. The result was the entire reconstruction of the navy of both the continents; as the one grew heavier, the other became thicker in proportion. The "Merrimac," the "Monitor," the "Tennessee," the "Weehawken" discharged enormous projectiles themselves, after having been armour-clad against the projectiles of others. In fact they did to others that which they would not they should do to them – that grand principle of immorality upon which rests the whole art of war.
Now if Barbicane was a great founder of shot, Nicholl was a great forger of plates; the one cast night and day at Baltimore, the other forged day and night at Philadelphia. As soon as ever Barbicane invented a new shot, Nicholl invented a new plate, each followed a current of ideas essentially opposed to the other. Happily for these citizens, so useful to their country, a distance of from fifty to sixty miles separated them from one another, and they had never yet met. Which of these two inventors had the advantage over the other it was difficult to decide from the results obtained. By last accounts, however, it would seem that the armour-plate would in the end have to give way to the shot; nevertheless, there were competent judges who had their doubts on the point.
At the last experiment the cylindro-conical projectiles of Barbicane stuck like so many pins in the Nicholl plates. On that day the Philadelphia iron-forger then believed himself victorious, and could not evince contempt enough for his rival; but when the other afterwards substituted for conical shot simple 600 lb. shells, at very moderate velocity, the captain was obliged to give in. In fact, these projectiles knocked his best metal plate to shivers.
Matters were at this stage, and victory seemed to rest with the shot, when the war came to an end on the very day when Nicholl had completed a new armour-plate of wrought steel. It was a masterpiece of its kind, and bid defiance to all the projectiles in the world. The captain had it conveyed to the Polygon at Washington, challenging the President of the Gun Club to break it. Barbicane, peace having been declared, declined to try the experiment.
Nicholl, now furious, offered to expose his plate to the shock of any shot, solid, hollow, round, or conical. Refused by the president, who did not choose to compromise his last success.
Nicholl, disgusted by this obstinacy, tried to tempt Barbicane by offering him every chance. He proposed to fix the plate within two hundred yards of the gun. Barbicane still obstinate in refusal. A hundred yards? Not even seventy-five!
"At fifty then!" roared the captain through the newspapers. "At twenty-five yards!! and I'll stand behind!!!"
Barbicane returned for answer that, even if Captain Nicholl would be so good as to stand in front, he would not fire any more.
Nicholl could not contain himself at this reply; threw out hints of cowardice; that a man who refused to fire a cannon-shot was pretty near being afraid of it; that artillerists who fight at six miles' distance are substituting mathematical formulas for individual courage.
To these insinuations Barbicane returned no answer; perhaps he never heard of them, so absorbed was he in the calculations for his great enterprise.
When his famous communication was made to the Gun Club, the captain's wrath passed all bounds; with his intense jealousy was mingled a feeling of absolute impotence. How was he to invent anything to beat this 900-feet Columbiad? What armour-plate could ever resist a projectile of 30,000 lbs. weight? Overwhelmed at first under this violent shock, he by and by recovered himself, and resolved to crush the proposal by the weight of his arguments.
He then violently attacked the labours of the Gun Club, published a number of letters in the newspapers, endeavoured to prove Barbicane ignorant of the first principles of gunnery. He maintained that it was absolutely impossible to impress upon any body whatever a velocity of 12,000 yards per second; that even with such a velocity a projectile of such a weight could not transcend the limits of the earth's atmosphere. Further still, even regarding the velocity to be acquired, and granting it to be sufficient, the shell could not resist the pressure of the gas developed by the ignition of 1,600,000 lbs. of powder; and supposing it to resist that pressure, it would be the less able to support that temperature; it would melt on quitting the Columbiad, and fall back in a red-hot shower upon the heads of the imprudent spectators.
Barbicane continued his work without regarding these attacks.
Nicholl then took up the question in its other aspects. Without touching upon its uselessness in all points of view, he regarded the experiment as fraught with extreme danger, both to the citizens, who might sanction by their presence so reprehensible a spectacle, and also to the towns in the neighbourhood of this deplorable cannon. He also observed that if the projectile did not succeed in reaching its destination (a result absolutely impossible), it must inevitably fall back upon the earth, and that the shock of such a mass, multiplied by the square of its velocity, would seriously endanger every point of the globe. Under the circumstances, therefore, and without interfering with the rights of free citizens, it was a case for the intervention of Government, which ought not to endanger the safety of all for the pleasure of one individual.
Spite of all his arguments, however, Captain Nicholl remained alone in his opinion. Nobody listened to him, and he did not succeed in alienating a single admirer from the President of the Gun Club. The latter did not even take the pains to refute the arguments of his rival.
Nicholl, driven into his last entrenchments, and not able to fight personally in the cause, resolved to fight with money. He published, therefore, in the Richmond Inquirer a series of wagers, conceived in these terms, and on an increasing scale: —
No. 1 (1000 dols.). – That the necessary funds for the experiment of the Gun Club will not be forthcoming.
No. 2 (2000 dols.). – That the operation of casting a cannon of 900 feet is impracticable, and cannot possibly succeed.
No. 3 (3000 dols.). – That it is impossible to load the Columbiad, and that the pyroxyle will take fire spontaneously under the pressure of the projectile.
No. 4 (4000 dols.). – That the Columbiad will burst at the first fire.
No. 5 (5000 dols.). – That the shot will not travel farther than six miles, and that it will fall back again a few seconds after its discharge.
It was an important sum, therefore, which the captain risked in his invincible obstinacy. He had no less than 15,000 dollars at stake.
Notwithstanding the importance of the challenge, on the 19th of May he received a sealed packet containing the following superbly laconic reply: —
"Baltimore, Oct. 19.
"Done.
"Barbicane."
CHAPTER XI.
FLORIDA AND TEXAS
One question yet remained to be decided: it was necessary to choose a favourable spot for the experiment. According to the advice of the Observatory of Cambridge, the gun must be fired perpendicularly to the plane of the horizon, that is to say, towards the zenith. Now the moon does not traverse the zenith, except in places situated between 0° and 28° of latitude. It became, then, necessary to determine exactly that spot on the globe where the immense Columbiad should be cast.
On the 20th of October, at a general meeting of the Gun Club, Barbicane produced a magnificent map of the United States. "Gentlemen," said he, in opening the discussion, "I presume that we are all agreed that this experiment cannot and ought not to be tried anywhere but within the limits of the soil of the Union. Now, by good fortune, certain frontiers of the United States extend downwards as far as the 28th parallel of the north latitude. If you will cast your eye over this map, you will see that we have at our disposal the whole of the southern portion of Texas and Florida."
It was finally agreed, then, that the Columbiad must be cast on the soil of either Texas or Florida. The result, however, of this decision was to create a rivalry entirely without precedent between the different towns of these two states.
The 28th parallel, on reaching the American coast, traverses the peninsula of Florida, dividing it into two nearly equal portions. Then, plunging into the Gulf of Mexico, it subtends the arc formed by the coast of Alabama, Mississippi, and Louisiana; then skirting Texas, off which it cuts an angle, it continues its course over Mexico, crosses the Sonora, Old California, and loses itself in the Pacific Ocean. It was, therefore, only those portions of Texas and Florida which were situated below this parallel which came within the prescribed conditions of latitude.
Florida, in its southern part, reckons no cities of importance; it is simply studded with forts raised against the roving Indians. One solitary town, Tampa Town, was able to put in a claim in favour of its situation.
In Texas, on the contrary, the towns are much more numerous and important. Corpus Christi, in the county of Nuaces, and all the cities situated on the Rio Bravo, Laredo, Comalites, San Ignacio on the Web, Rio Grande City on the Starr, Edinburgh in the Hidalgo, Santa Rita, Elpanda, Brownsville in the Cameron, formed an imposing league against the pretensions of Florida. So, scarcely was the decision known, when the Texan and Floridan deputies arrived at Baltimore in an incredibly short space of time. From that very moment President Barbicane and the influential members of the Gun Club were besieged day and night by formidable claims. If seven cities of Greece contended for the honour of having given birth to Homer, here were two entire states threatening to come to blows about the question of a cannon.
The rival parties promenaded the streets with arms in their hands; and at every occasion of their meeting a collision was to be apprehended which might have been attended with disastrous results. Happily the prudence and address of President Barbicane averted the danger. These personal demonstrations found a division in the newspapers of the different states. The New York Herald and the Tribune supported Texas, while the Times and the American Review espoused the cause of the Floridan Deputies. The members of the Gun Club could not decide to which to give the preference.
Texas produced its array of twenty-six counties; Florida replied that twelve counties were better than twenty-six in a country only one-sixth part of the size.
Texas plumed itself upon its 330,000 natives; Florida with a far smaller territory, boasted of being much more densely populated with 56,000.
The Texians, through the columns of the Herald, claimed that some regard should be had to a state which grew the best cotton in all America, produced the best green oak for the service of the navy, and contained the finest oil, besides iron mines, in which the yield was fifty per cent. of pure metal.
To this the American Review replied that the soil of Florida, although not equally rich, afforded the best conditions for the moulding and casting of the Columbiad, consisting as it did of sand and argillaceous earth.
"That may be all very well," replied the Texians; "but you must first get to this country. Now the communications with Florida are difficult, while the coast of Texas offers the bay of Galveston, which possesses a circumference of fourteen leagues, and is capable of containing the navies of the entire world!"
"A pretty notion truly," replied the papers in the interest of Florida, "that of Galveston Bay below the 29th parallel! Have we not got the bay of Espiritu Santo, opening precisely upon the 28th degree, and by which ships can reach Tampa Town by direct route?"
"A fine bay! half choked with sand!" "Choked yourselves!" returned the others.
Thus the war went on for several days, when Florida endeavoured to draw her adversary away on to fresh ground; and one morning the Times hinted that, the enterprise being essentially American, it ought not to be attempted upon other than purely American territory.
To these words Texas retorted, "American! are we not as much so as you? Were not Texas and Florida both incorporated into the Union in 1845?"
"Undoubtedly," replied the Times; "but we have belonged to the Americans ever since 1820."
"Yes!" returned the Tribune; "after having been Spaniards or English for 200 years, you were sold to the United States for five million dollars!"
"Well! and why need we blush for that? Was not Louisiana bought from Napoleon in 1803 at the price of sixteen million dollars?"
"Scandalous!" roared the Texan deputies. "A wretched little strip of country like Florida to dare to compare itself to Texas, who, in place of selling herself, asserted her own independence, drove out the Mexicans in March 2, 1836, and declared herself a federal republic after the victory gained by Samuel Houston, on the banks of the San Jacinto, over the troops of Santa Anna! – a country, in fine, which voluntarily annexed itself to the United States of America!"
"Yes; because it was afraid of the Mexicans!" replied Florida.
"Afraid!" From this moment the state of things became intolerable. A sanguinary encounter seemed daily imminent between the two parties in the streets of Baltimore. It became necessary to keep an eye upon the deputies.
President Barbicane knew not which way to look. Notes, documents, letters full of menaces showered down upon his house. Which side ought he to take? As regarded the appropriation of the soil, the facility of communication, the rapidity of transport, the claims of both states were evenly balanced. As for political prepossessions, they had nothing to do with the question.
This dead block had existed for some little time, when Barbicane resolved to get rid of it at once. He called a meeting of his colleagues, and laid before them a proposition which, it will be seen, was profoundly sagacious.
"On carefully considering," he said, "what is going on now between Florida and Texas, it is clear that the same difficulties will recur with all the towns of the favoured state. The rivalry will descend from state to city, and so on downwards. Now Texas possesses eleven towns within the prescribed conditions, which will further dispute the honour and create us new enemies, while Florida has only one. I go in, therefore, for Florida and Tampa Town."
This decision, on being made known, utterly crushed the Texan deputies. Seized with an indescribable fury, they addressed threatening letters to the different members of the Gun Club by name. The magistrates had but one course to take, and they took it. They chartered a special train, forced the Texians into it whether they would or no; and they quitted the city with a speed of thirty miles an hour.
Quickly, however, as they were despatched, they found time to hurl one last and bitter sarcasm at their adversaries.
Alluding to the extent of Florida, a mere peninsula confined between two seas, they pretended that it could never sustain the shock of the discharge, and that it would "bust up" at the very first shot.
"Very well, let it bust up!" replied the Floridans, with a brevity worthy of the days of ancient Sparta.
