people a
hundred years ago than this new scheme appears now."

Thus they sat and talked, or studied maps and star-charts, or the stars
themselves, while the hours quickly passed and they shot through space.
They had now a straight stretch of over three hundred million miles,
and had to cross the orbits of innumerable asteroids on the way. The
apparent size of the sun had by this time considerably decreased, and
the interior of the Callisto was no longer uncomfortably warm. They
divided the day into twenty-four hours from force of habit, and drew
the shades tightly during what they considered night, while Bearwarden
distinguished himself as a cook.

CHAPTER III.

HEAVENLY BODIES.

The following day, while in their observatory, they saw something not
many miles ahead. They watched it for hours, and in fact all day, but
notwithstanding their tremendous speed they came but little nearer.

"They say a stern chase is a long one," said Bearwarden; "but that
beats anything I have ever seen."

After a while, however, they found they WERE nearer, the time taken
having been in part due to the deceptive distance, which was greater
than they supposed.

"A comet!" exclaimed Cortlandt excitedly. "We shall really be able to
examine it near."

"It's going in our direction," said Ayrault, "and at almost exactly our
speed."

While the sun shone full upon it they brought their camera into play,
and again succeeded in photographing a heavenly body at close range.
The nucleus or head was of course turned towards the sun; while the
tail, which they could see faintly, preceded it, as the comet was
receding towards the cold and dark depths of space. The head was only
a few miles in diameter, for it was a small comet, and was composed of
grains and masses of stone and meteoric iron. Many of the grains were
no larger than peas or mustard-seeds; no mass was more than four feet
in diameter, and all of them had very irregular shapes. The space
between the particles was never less than one hundred times their
masses.

"We can move about within it," said Ayrault, as the Callisto entered
the aggregation of particles, and moved slowly forward among them.

The windows in the dome, being made of toughened glass, set somewhat
slantingly so as to deflect anything touching them, and having,
moreover, the pressure of the inside air to sustain them, were fairly
safe, while the windows