"But then," replied the major, "you will have to give the projectile enormous dimensions."
"No. Please grant me your attention. You know that optical instruments have acquired great perfection; certain telescopes increase objects six thousand, and bring the moon to within a distance of forty miles. Now at that distance objects sixty feet square are perfectly visible. The power of penetration of the telescope has not been increased, because that power is only exercised to the detriment of their clearness, and the moon, which is only a reflecting mirror, does not send a light intense enough for the telescopes to increase objects beyond that limit."
"Very well, then, what do you mean to do?" asked the general. "Do you intend giving a diameter of sixty feet to your projectile?"
"You are not going to take upon yourself the task of making the moon more luminous?"
"That's rather strong!" exclaimed Maston.
"Yes, but simple," answered Barbicane. "If I succeed in lessening the density of the atmosphere which the moon's light traverses, shall I not render that light more intense?"
"In order to obtain that result I shall only have to establish my telescope upon some high mountain. We can do that."
"I give in," answered the major; "you have such a way of simplifying things! 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 a diameter of nine feet?"
"Allow me to inform you, however," returned Major Elphinstone, "that its weight will still be--"
"Oh, major!" answered Barbicane, "before discussing its weight allow me to tell you that our forefathers did marvels in that way. Far be it from me to pretend that ballistics have not progressed, but it is well to know that in the Middle Ages surprising results were obtained, I dare affirm, 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 hurled stone bullets that weighed 1,900 lbs.; at Malta, in the time of its knights, a certain cannon of Fort Saint Elme hurled projectiles weighing 2,500 lbs. According to a French historian, under Louis XI. a mortar hurled a bomb of 500 lbs. only; but that bomb, fired at the Bastille, a place where mad men imprisoned wise ones, fell at Charenton, where wise men imprison mad ones."