en erected in its
neighborhood, and their safety would be imperilled by the flying
fragments. The fact happened to come to my knowledge.

"Here is an opportunity," I said to Mr. Edison, "to try the powers of
your machine on a large scale."

"Capital," he instantly replied. "I shall go at once."

For the work now in hand it was necessary to employ a battery of
disintegrators, since the field of destruction covered by each was
comparatively limited. All of the impending portions of the wall must be
destroyed at once and together, for otherwise the danger would rather be
accentuated rather than annihilated. The disintegrators were placed upon
the roof of a neighboring building, so adjusted that their fields of
destruction overlapped one another upon the wall. Their indexes were all
set to correspond with the vibration period of the peculiar kind of
brick of which the wall consisted. Then the energy was turned on, and a
shout of wonder arose from the multitudes which had assembled at a safe
distance to witness the experiment.

The wall did not fall; it did not break asunder; no fragments shot this
way and that and high in the air; there was no explosion; no shock or
noise disturbed the still atmosphere--only a soft whirr, that seemed to
pervade everything and to tingle in the nerves of the spectators;
and--what had been was not! The wall was gone! But high above and all
around the place where it had hung over the street with its threat of
death there appeared, swiftly billowing outward in every direction, a
faint bluish cloud. It was the scattered atoms of the destroyed wall.

And now the cry "On to Mars!" was heard on all sides. But for such an
enterprise funds were needed--millions upon millions. Yet some of the
fairest and richest portions of the earth had been impoverished by the
frightful ravages of those enemies who had dropped down upon them from
the skies. Still, the money must be had. The salvation of the planet, as
everyone was now convinced, depended upon the successful negotiation of
a gigantic war fund, in comparison with which all the expenditures in
all of the wars that had been waged by the nations for 2,000 years would
be insignificant. The electrical ships and the vibration engines must be
constructed by scores and thousands. Only Mr. Edison's immense resources
and unrivaled equipment had enabled him to make the models whose powers
had been so satisfactorily shown. But to multiply these upon a war scal