"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 the 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."