ume of a sphere!"

"A moment's breathing time, please."

"Breathing time, indeed! A mathematician should not want breathing
time! Come, multiply the surface by the third of the radius. Don't you
recollect?"

Captain Servadac applied himself to his task while the by-standers
waited, with some difficulty suppressing their inclination to laugh.
There was a short silence, at the end of which Servadac announced that
the volume of the comet was 47,880,000 cubic miles.

"Just about 5,000 times less than the earth," observed the lieutenant.

"Nice little comet! pretty little comet!" said Ben Zoof.

The professor scowled at him, and was manifestly annoyed at having the
insignificant dimensions of his comet pointed out in so disparaging
a manner. Lieutenant Procope further remarked that from the earth
he supposed it to be about as conspicuous as a star of the seventh
magnitude, and would require a good telescope to see it.

"Ha, ha!" laughed the orderly, aloud; "charming little comet! so pretty;
and so modest!"

"You rascal!" roared the professor, and clenched his hand in passion, as
if about to strike him. Ben Zoof laughed the more, and was on the point
of repeating his satirical comments, when a stern order from the captain
made him hold his tongue. The truth was that the professor was just as
sensitive about his comet as the orderly was about Montmartre, and if
the contention between the two had been allowed to go on unchecked, it
is impossible to say what serious quarrel might not have arisen.

When Professor Rosette's equanimity had been restored, he said, "Thus,
then, gentlemen, the diameter, the surface, the volume of my comet are
settled; but there is more to be done. I shall not be satisfied until,
by actual measurement, I have determined its mass, its density, and the
force of gravity at its surface."

"A laborious problem," remarked Count Timascheff.

"Laborious or not, it has to be accomplished. I am resolved to find out
what my comet weighs."

"Would it not be of some assistance, if we knew of what substance it is
composed?" asked the lieutenant.

"That is of no moment at all," replied the professor; "the problem is
independent of it."

"Then we await your orders," was the captain's reply.

"You must understand, however," said Rosette, "that there are various
preliminary calculations to be made; you will have to wait till they are
finished."

"As long as you please," said the count.

"No hurry a