nd all the rest of the mess."

"We might--show him--the big Ray," ventured Atterbury. "The thing--can
be pointed up--and I can--keep the turbine running. You can start--the
fire--as soon as you--hear his motors--and I'll shut down--as soon as I
see your fire."

"Good idea!" agreed Bennie. "Only don't run continuously. Show the Ray
for a minute every quarter of an hour, and on no account start up after
you see the fire. If he thought the vertical beam was a searchlight and
flew through it----" Bennie shuddered at the thought of Burke driving
his aeroplane through the Ray that had shattered the Atlas Mountains.

So it was arranged. Half an hour after sunset Atterbury shut himself up
in the Ring, and while Bennie climbed the trail leading to his post on
the plateau, he heard the creaking of the great inductor as it slowly
turned on its trunions.

It was pitch dark by the time he reached the pitifully small pile of
brush which they had collected, and he poured some of the oil over it
and sat down, drawing a blanket around his shoulders. He felt very much
alone. Suppose the inductor failed to work? Suppose Atterbury turned the
Ray on him? Suppose.... But his musings were shattered by a noise from
the valley, a sound like that of escaping steam, and a moment later the
Lavender Ray shot up toward the zenith. Bennie lay on his back and
watched it, mindful of the night before the last when he had watched the
Ray from the tower descending upon the cliff. He wondered if he should
see any meteorites kindle in its path, but nothing appeared and the Ray
died down, leaving everything in darkness again. Fifteen minutes passed
and again the ghostly beam shot up into the night sky. Bennie looked at
his watch. It was nearly half-past eight. The cold made him sleepy. He
drew the blanket about him....

Two hours later through his half-dreams he caught the faint sound for
which he had been listening. At first he was not sure. It might be the
turbine alternator of the Ring running by its own inertia for some time
after the discharge had ceased. But no, it was growing louder
momentarily, and appeared to come from high up in the air. Now it died
away to nothingness, and now it swelled in volume, and again died away.
But at each subsequent recurrence it was louder than before. There was
no longer any doubt. Burke was coming! It was time to start the brush
pile. He lit match after match, only for the wind to blow them out. Yet
all the time t