However, by dint of a natural phenomenon, identical
with that produced on the moon when she is in her
octants, the contour of the terrestrial globe could
be traced. Its entire disc appeared slightly visible
through an effect of pale light, less appreciable
than that of the moon. The reason of this lessened
intensity is easy to understand. When this reflection
is produced on the moon it is caused by the solar rays
which the earth reflects upon her satellite.
Here it was caused by the solar rays reflected from
the moon upon the earth. Now terrestrial light
is thirteen times more intense than lunar light on
account of the difference of volume in the two bodies.
Hence it follows that in the phenomenon of the pale
light the dark part of the earth’s disc is less
clearly outlined than that of the moon’s disc,
because the intensity of the phenomenon is in proportion
to the lighting power of the two stars. It must
be added that the terrestrial crescent seems to form
a more elongated curve than that of the disc—a
pure effect of irradiation.
Whilst the travellers were trying to pierce the profound
darkness of space, a brilliant shower of falling stars
shone before their eyes. Hundreds of meteors,
inflamed by contact with the atmosphere, streaked
the darkness with luminous trails, and lined the cloudy
part of the disc with their fire. At that epoch
the earth was in her perihelion, and the month of
December is so propitious to these shooting stars that
astronomers have counted as many as 24,000 an hour.
But Michel Ardan, disdaining scientific reasoning,
preferred to believe that the earth was saluting with
her finest fireworks the departure of her three children.
This was all they saw of the globe lost in the darkness,
an inferior star of the solar world, which for the
grand planets rises or sets as a simple morning or
evening star! Imperceptible point in space, it
was now only a fugitive crescent, this globe where
they had left all their affections.
For a long time the three friends, not speaking, yet
united in heart, watched while the projectile went
on with uniformly decreasing velocity. Then irresistible
sleep took possession of them. Was it fatigue
of body and mind? Doubtless, for after the excitement
of the last hours passed upon earth, reaction must
inevitably set in.
“Well,” said Michel, “as we must
sleep, let us go to sleep.”
Stretched upon their beds, all three were soon buried
in profound slumber.
But they had not been unconscious for more than a
quarter of an hour when Barbicane suddenly rose, and,
waking his companions, in a loud voice cried—
“I’ve found it!”
“What have you found?” asked Michel Ardan,
jumping out of bed.
“The reason we did not hear the detonation of
the Columbiad!”
“Well?” said Nicholl.
“It was because our projectile went quicker
than sound.”
