r
increased in size in the telescope, and he was now invisible. The only
way I could tell would be to wait until after many days had elapsed, and
if Mars did not finally come into view, I should know something was
wrong. But it would be too late then; there would be no winds or tides,
no weight or buoyancy, nothing to move us out of that dreadful calm
where even gravity does not exist. That must be avoided at every cost!
But might we not be very near it now? Weight had been practically
nothing for a month, within an hour it might be positively nothing,
and----

The doctor's mutterings interrupted these thoughts. "The power with
which to travel was so simple and so vast! It all lay hidden in that
elementary law of magnetism, like poles repel and unlike poles attract.
But the road to travel and the problems by the way, those were the hard
things!"

He was putting them all in the past tense, as if he had already solved
them! But what was that law of magnetism he mentioned? Perhaps he would
reveal his secrets to me in his ravings! I must mark every word he said;
for it was clear I must solve the problem, he would not be well in time.
I must brush the cobwebs from my meagre science and struggle with his
invention.

"Unlike poles attract," he had said. Then Earth and matter must normally
have unlike poles, and to make Earth repel matter it would only be
necessary to change the polarization of the matter. Yes, he had told me
it was all accomplished by polarizing the steel and iron of the
projectile! When they were made the same pole as the Earth, then she
repelled them. But if the whole thing were so simple, why had it never
been discovered before? Ah, that is the strong shield behind which
incredulity always takes refuge!

I ventured near the gravity apparatus and examined it carefully. There
was a small thing which looked like the switchboard of a telegraph
office. The perforations in it were all in a row, and the ten holes were
now filled with little brass pegs, which were suspended from above on
small spiral springs. These were evidently the points of communication
of the negative current to the framework of the projectile. It certainly
would do no harm to pull out one of these pegs, as that would only
slightly diminish the current. At least I would risk it. My fingers had
scarcely closed upon the brass, when I was given such a violent shock as
to be thrown powerfully across the compartment; and had my body weighed
a