t of the sun, the terrestrial globe might
make a curve towards the wandering star, and the earth would become its
satellite, and would be dragged away to such a distance that the rays of
the sun would have no action on its surface."

"That might happen certainly," answered Barbicane, "but the consequences
would not be so redoubtable as you would suppose."

"How so?"

"Because heat and cold would still be pretty well balanced upon our
globe. It has been calculated that if the earth had been carried away by
the comet of 1861, it would only have felt, when at its greatest
distance from the sun, a heat sixteen times greater than that sent to us
by the moon--a heat which, when focussed by the strongest lens, produces
no appreciable effect."

"Well?" said Michel.

"Wait a little," answered Barbicane. "It has been calculated that at its
perihelion, when nearest to the sun, the earth would have borne a heat
equal to 28,000 times that of summer. But this heat, capable of
vitrifying terrestrial matters, and of evaporating water, would have
formed a thick circle of clouds which would have lessened the excessive
heat, hence there would be compensation between the cold of the aphelion
and the heat of the perihelion, and an average probably supportable."

"At what number of degrees do they estimate the temperature of the
planetary space?"

"Formerly," answered Barbicane, "it was believed that this temperature
was exceedingly low. By calculating its thermometric diminution it was
fixed at millions of degrees below zero. It was Fourier, one of Michel's
countrymen, an illustrious _savant_ of the _Academie des Sciences_, who
reduced these numbers to a juster estimation. According to him, the
temperature of space does not get lower than 60 deg. Centigrade."

Michel whistled.

"It is about the temperature of the polar regions," answered Barbicane,
"at Melville Island or Fort Reliance--about 56 deg. Centigrade below zero."

"It remains to be proved," said Nicholl, "that Fourier was not mistaken
in his calculations. If I am not mistaken, another Frenchman, M.
Pouillet, estimates the temperature of space at 160 deg. below zero. We
shall be able to verify that."

"Not now," answered Barbicane, "for the solar rays striking directly
upon our thermometer would give us, on the contrary, a very elevated
temperature. But when we get upon the moon, during the nights, a
fortnight long, which each of its faces endures alternately, we shall