f gas, and all the expansive force of
the powder will be employed in the propulsion."

"Hurrah! hurrah!" said Maston, "we have our cannon."

"Not yet," answered Barbicane, calming his impatient friend with his
hand.

"Why not?"

"Because we have not discussed its form. Shall it be a cannon, howitzer,
or a mortar?"

"A cannon," replied Morgan.

"A howitzer," said the major.

"A mortar," exclaimed J.T. Maston.

A fresh discussion was pending, each taking the part of his favourite
weapon, when the president stopped it short.

"My friends," said he, "I will soon make you agree. Our Columbiad will
be a mixture of all three. It will be a cannon, because the
powder-magazine will have the same diameter as the chamber. It will be a
howitzer, because it will hurl an obus. Lastly, it will be a mortar,
because it will be pointed at an angle of 90 deg., and that without any
chance of recoil; unalterably fixed to the ground, it will communicate
to the projectile all the power of impulsion accumulated in its body."

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

"One question," said Elphinstone, "and will this _canobusomortar_ be
rifled?"

"No," answered Barbicane. "No, we must have an enormous initial speed,
and you know very well that a shot leaves a rifle less rapidly than a
smooth-bore."

"True," answered the major.

"Well, we have it this time," repeated J.T. Maston.

"Not quite yet," replied the president.

"Why not?"

"Because we do not yet know of what metal it will be made."

"Let us decide that without delay."

"I was going to propose it to you."

The four members of the committee each swallowed a dozen sandwiches,
followed by a cup of tea, and the debate recommenced.

"Our cannon," said Barbicane, "must be possessed of great tenacity,
great hardness; it must be infusible by heat, indissoluble, and
inoxydable by the corrosive action of acids."

"There is no doubt about that," answered the major, "and as we shall
have to employ a considerable quantity of metal we shall not have much
choice."

"Well, then," said Morgan, "I propose for the fabrication of the
Columbiad the best alloy hitherto known--that is to say, 100 parts of
copper, 12 of tin, and 6 of brass."

"My friends," answered the president, "I agree that this composition has
given excellent results; but in bulk it would be too dear and very hard
to work. I therefore think we must adopt an excellent material, but
cheap, su