nstead how long was needed to bridge the sharp gap of a radio-power
transmitter; how much time was needed for anode and cathode each to
recognize the other. Something of this was passing in confusion through
his mind while his more conscious faculties were tensing his body for
the fatal impact he knew must come.

Without thinking the thought in words he knew that the luminous walls
had receded. They were more distant now; their glow came to him from far
above, and, as his falling body turned again and again in air, he saw
that below him was nothing but a vast emptiness filled with luminous
vapors that swirled and writhed.

Then the last gleam of lighted walls faded; he was falling at terrific
speed through a black tempest whose winds tore and screamed about him.

* * * * *

It was his own falling speed that made these winds; there remained with
him enough of reasoning power to realize this. And he waited, and
marveled that he could fall so tremendous a distance. First had been
the great shaft down which he had plunged; then, as it widened, had come
this greater void. The crater of Hercules must have opened, into a vast
shell or a cavern of incredible depth. The winged things of the Moon
knew of it; they had cast him to his death--him and the girl.

Her slowly turning body was not far away; it was as if they two hung
suspended in air, while frightful blasts of whatever gas filled this
space whipped and shrieked past and wrapped them round with a terrific
pressure. And then the tempest ceased. Slowly the blasts diminished; the
pressure relaxed; gradually the sense of falling passed away, and with
this there came a glimpse of light.

Again the walls glowed as they had before, but far off in the distance.
Chet saw them grow luminous while he seemed hung motionless in space.
Then once more they drew away from him; once more he knew he was falling
away from that light--plunging again into the depths he had traversed.

And now, despite the oxygen that came to him uninterruptedly, he found
his head swimming. The limit of human endurance had been reached.

Desperately he tried to bring his reason to bear upon this miracle that
had happened. He had not struck; instead of falling to his death he had
cushioned against something; he was falling again where, not far away,
another metal-clad figure hung limply in air and fell as he fell. And
with that knowledge the whirling turmoil within his brai