particular facts; Barbicane and Nicholl always serious, Michel
Ardan always enthusiastic. The projectile, its situation,
its direction, incidents which might happen, the precautions
necessitated by their fall on to the moon, were inexhaustible
matters of conjecture.
As they were breakfasting, a question of Michel’s, relating to
the projectile, provoked rather a curious answer from Barbicane,
which is worth repeating. Michel, supposing it to be roughly
stopped, while still under its formidable initial speed, wished
to know what the consequences of the stoppage would have been.
“But,” said Barbicane, “I do not see how it could have been stopped.”
“But let us suppose so,” said Michel.
“It is an impossible supposition,” said the practical Barbicane;
“unless that impulsive force had failed; but even then its speed
would diminish by degrees, and it would not have stopped suddenly.”
“Admit that it had struck a body in space.”
“What body?”
“Why that enormous meteor which we met.”
“Then,” said Nicholl, “the projectile would have been broken
into a thousand pieces, and we with it.”
“More than that,” replied Barbicane; “we should have been burned
to death.”
“Burned?” exclaimed Michel, “by Jove! I am sorry it did not
happen, `just to see.'”
“And you would have seen,” replied Barbicane. “It is known now
that heat is only a modification of motion. When water is
warmed– that is to say, when heat is added to it–its particles
are set in motion.”
“Well,” said michel, “that is an ingenious theory!”
“And a true one, my worthy friend; for it explains every
phenomenon of caloric. Heat is but the motion of atoms, a
simple oscillation of the particles of a body. When they apply
the brake to a train, the train comes to a stop; but what
becomes of the motion which it had previously possessed? It is
transformed into heat, and the brake becomes hot. Why do they
grease the axles of the wheels? To prevent their heating,
because this heat would be generated by the motion which is thus
lost by transformation.”
“Yes, I understand,” replied Michel, “perfectly. For example,
when I have run a long time, when I am swimming, when I am
perspiring in large drops, why am I obliged to stop?
Simply because my motion is changed into heat.”
Barbicane could not help smiling at Michel’s reply; then,
returning to his theory, said:
“Thus, in case of a shock, it would have been with our
projectile as with a ball which falls in a burning state after
having struck the metal plate; it is its motion which is turned
into heat. Consequently I affirm that, if our projectile had
struck the meteor, its speed thus suddenly checked would have
raised a heat great enough to turn it into vapor instantaneously.”
“Then,” asked Nicholl, “what would happen if the earth’s motion
were to stop suddenly?”
“Her temperature would be raised to such a pitch,” said
Barbicane, “that she would be at once reduced to vapor.”
“Well,” said Michel, “that is a way of ending the earth which
will greatly simplify things.”
“And if the earth fell upon the sun?” asked Nicholl.
“According to calculation,” replied Barbicane, “the fall would
develop a heat equal to that produced by 16,000 globes of coal,
each equal in bulk to our terrestrial globe.”
“Good additional heat for the sun,” replied Michel Ardan, “of
which the inhabitants of Uranus or Neptune would doubtless not
complain; they must be perished with cold on their planets.”
“Thus, my friends,” said Barbicane, “all motion suddenly stopped
produces heat. And this theory allows us to infer that the heat
of the solar disc is fed by a hail of meteors falling
incessantly on its surface. They have even calculated—-”
“Oh, dear!” murmured Michel, “the figures are coming.”
“They have even calculated,” continued the imperturbable Barbicane,
“that the shock of each meteor on the sun ought to produce a heat
equal to that of 4,000 masses of coal of an equal bulk.”
“And what is the solar heat?” asked Michel.
“It is equal to that produced by the combustion of a stratum of
coal surrounding the sun to a depth of forty-seven miles.”
“And that heat—-”
“Would be able to boil two billions nine hundred millions of