"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 a
compact mass. This precious metal possesses the whiteness of silver, the
indestructibility of gold, the tenacity of iron, the fusibility of
copper, the lightness of glass; it is easily wrought, and is very widely
distributed in nature, as aluminium forms the basis of most rocks; it is
three times lighter than iron, and seems to have been created expressly
to furnish us with the material for our projectile!"

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

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

"It was so," answered Barbicane; "when first discovered a pound of
aluminium 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 give
in; "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. "A
projectile of 108 inches in diameter and 12 inches thick would weigh, if