re readily understand how large numbers of
human beings could be destroyed by such fabulous quantities of boiling
lava as were capable of being thrown from this pit. There is no doubt
that the lava and ashes hurled from this crater alone would send a
withering blast of death-dealing for many hundreds of miles around.

If you have never been privileged to look upon this ponderous chasm face
to face, improve your first opportunity to get a glimpse of it through
as powerful a telescope as possible.

CHAPTER III.

A Visit to Mars.

I need not describe the manner of my flight. It is enough to say that,
to my delight, I reached our neighbor planet called Mars, and at once
proceeded to study its physical features and its human life.

Everything was vastly different from what I had been long accustomed to
see and to imagine, and I felt quite assured that I was living in a
dream. But I knew of no way to convince myself as to my bearings, so I
concluded to make the best use of my time and opportunities, and leave
questionings to the future.

As a physical world Mars bears a most striking resemblance to our Earth.
The length of its year is six hundred and eighty-seven of our days, and
the length of its day is twenty-four hours and thirty-seven minutes. Its
diameter is about one-half that of the Earth and its distance from the
Sun is 142,000,000 miles. Even from our own world we can discern
through a good telescope the changing colors of the planet, due to the
recurring seasons, each one of which is almost twice the length of ours.

There is relatively much less water on Mars than is found on our Earth,
and gravity on its surface is only thirty-eight per cent. of terrestrial
gravity. Imagine, then, how light everything must be. This may account
somewhat for the physical proportions of its inhabitants, for they are
over twice our size, and in appearance resemble us but little. They have
four arms, two extra ones extending from a point just above the knees.
The two lower arms act as servants to the two higher. Thus are the four
used at one time in harmony.

Mars is an older world than ours, and although it receives only one-half
as much heat from the sun yet it is almost of the same temperature,
owing to a peculiar condition of the atmosphere which we would call
"heat retentivity."

Some scientists and philosophers will at once say that such atmospheric
conditions are contrary to reason and natural law, but they mus