n-wheel revolutions. Whole
cities were ruined, fertile valleys covered and human life was almost
annihilated."

I knew what my informant meant by "one and one-half wagon-wheel
revolutions." This would be a period of about forty days and nights of
earthly time. Do you wonder that my mind flew back to the forty days and
nights of rain that destroyed, at one time, on our Earth, the whole
human family, except the few who were saved in the ark?

"What are the evidences of this horrible world-ending?" I asked.

"They are on every hand. Have you not yet seen the vast craters, the
mountains of barren cinder, the stumps of immense pillars, partly
excavated? All this, and very much more, silently unfolds a tale of
horror that can be faintly pictured only by the imagination. Think of a
holocaust so terrible that one hundred million human creatures are
thereby swept into death in the narrow compass of forty days! The
records that have been brought down to us by the few survivors indicate
the continual wails of horror rending the sky while the volcanic
disturbances continued. Thousands and millions ran from place to place
to find shelter from the storm of fire. At one place the surface would
open and at another the lava would run. Fate, with a merciless hand,
was dragging each one into one or another of the inevitable pits."

"How many were saved?" I asked with deepening interest.

"Parts of only eight families aggregating nineteen human beings."

"And how many people are on the Moon now?"

"Almost forty million."

"How do you account for this slow growth?" I asked after I had explained
that on our globe a much larger number of inhabitants sprang from a
smaller number than nineteen in a shorter period of time.

This allusion cost me much explanation, and, after I had selfishly
brushed his rising questions aside, I learned that large companies of
the Moonites had been swept into death by frequent volcanic outbursts
all along the line of the centuries.

No one can estimate my interest as I continued the conversation. But
finally I decided to stroll through certain parts of the city and,
thinking it advisable to give no notice of my departure, I suddenly
vanished from his sight. However, before leaving the room, I observed
that my bewildered auditor conjectured for a long time and reached his
former conclusion that he had been in touch with an apparition.

Again I resumed my visible form and walked along one of the principa