fully twenty feet, and as it
reached its place once more after closing behind us, great cylinders of
steel had dropped from the ceiling behind it and fitted their lower
ends into apertures countersunk in the floor.

A second and third door receded before me and slipped to one side as
the first, before I reached a large inner chamber where I found food
and drink set out upon a great stone table. A voice directed me to
satisfy my hunger and to feed my calot, and while I was thus engaged my
invisible host put me through a severe and searching cross-examination.

"Your statements are most remarkable," said the voice, on concluding
its questioning, "but you are evidently speaking the truth, and it is
equally evident that you are not of Barsoom. I can tell that by the
conformation of your brain and the strange location of your internal
organs and the shape and size of your heart."

"Can you see through me?" I exclaimed.

"Yes, I can see all but your thoughts, and were you a Barsoomian I
could read those."

Then a door opened at the far side of the chamber and a strange, dried
up, little mummy of a man came toward me. He wore but a single article
of clothing or adornment, a small collar of gold from which depended
upon his chest a great ornament as large as a dinner plate set solid
with huge diamonds, except for the exact center which was occupied by a
strange stone, an inch in diameter, that scintillated nine different
and distinct rays; the seven colors of our earthly prism and two
beautiful rays which, to me, were new and nameless. I cannot describe
them any more than you could describe red to a blind man. I only know
that they were beautiful in the extreme.

The old man sat and talked with me for hours, and the strangest part of
our intercourse was that I could read his every thought while he could
not fathom an iota from my mind unless I spoke.

[Illustration: The old man sat and talked with me for hours.]

I did not apprise him of my ability to sense his mental operations, and
thus I learned a great deal which proved of immense value to me later
and which I would never have known had he suspected my strange power,
for the Martians have such perfect control of their mental machinery
that they are able to direct their thoughts with absolute precision.

The building in which I found myself contained the machinery which
produces that artificial atmosphere which sustains life on Mars. The
secret of the entire