y
from lookout to lookout while he searched the heavens.

"It's damned lucky for us that you made a slight error," Chet was
telling the other.

"Error?" Kreiss challenged. "Impossible!"

"Then you and I are dead right this minute," Chet told him. "We are
crossing the orbit of the Dark Moon--crossing at twenty thousand miles
per hour relative to Earth, slightly in excess of that figure relative
to the Dark Moon. If it had been here--!" He had been watching
Harkness anxiously; he bit off his words as the binoculars were thrust
into his hand.

"There she comes," Harkness told him quietly; "it's up to you!"

But Chet did not need the glasses. With his unaided eyes he could see
a faint circle of violet light. It lay ahead and slightly above, and
it grew visibly larger as he watched. A ring of nothingness, whose
outline was the faintest shimmering halo; more of the distant stars
winked out swiftly behind that ghostly circle; it was the Dark
Moon!--and it was rushing upon them!

* * * * *

Chet swung an instrument upon it. He picked out a jet of violet light
that could be distinguished, and he followed it with the cross-hairs
while he twirled a micrometer screw; then he swiftly copied the
reading that the instrument had inscribed. The invisible disk with its
ghostly edge of violet was perceptibly larger as he slammed over the
control-ball to up-end them in air.

Under the control-room's nitron illuminator the cheeks of Herr Doktor
Kreiss were pale and bloodless as if his heart had ceased to function.
Harkness had moved quietly back to the side of Diane Delacouer and was
holding her two hands firmly in his.

The very air seemed charged with the quick tenseness of emotions.
Schwartzmann must have sensed it even before he saw the onrushing
death. Then he leaped to a lookout, and, an instant later, sprang at
Chet calmly fingering the control.

"Fool!" he screamed, "you would kill us all? Turn away from it! Away
from it!"

He threw himself in a frenzy upon the pilot. The detonite pistol was
still in his hand. "Quick!" he shouted. "Turn us!"

Harkness moved swiftly, but the scientist, Kreiss, was nearer; it was
he who smashed the gun-hand down with a quick blow and snatched at the
weapon.

Schwartzmann was beside himself with rage. "You, too?" he demanded.
"Giff it me--traitor!"

* * * * *

But the tall man stood uncompromisingly erect. "Never," he sa