in his headlong rush, he
pushed the bewildered girl through the open port, out into the
overwhelming, intangible blackness. Nona's smothered cry of fear came
to him as the next instant he stepped forward and left the solid
footing to float in sudden weightlessness in a vast sea of
nothingness.

The girl reached out and caught his arm convulsively. Even through the
fabric of their suits he could feel her trembling. Pemberton had taken
good care to retain a hold on the edge of the open air-lock. The two
swung unsteadily.

"What is the reason for this?" Grant sensed, rather, than heard, the
tremor in her voice. She was making a desperate effort to control
herself. "We'll be lost--out here in space."

"Don't worry," he said soothingly. "I'll explain in due course. In the
meantime you'll have to trust me. Did you see where that invisible ray
held when it illumined the last Ganymedan?"

"Ganymedan?" she echoed in surprise. "What makes you think--"

"Never mind that. Did you?" he insisted.

"Yes," she admitted, "it was about over there." She indicated the spot
with an outthrust arm. "About a hundred yards, I should judge."

"Exactly," he agreed. "Well, young lady, our lives, and far more,
depend upon our reaching that exact line in space immediately."

"I don't know what you are talking about, but even so, how can we
make it? I'm not a rocket."

"It's difficult, I admit, but we must. Now hold on tight to my arm,
and press your feet firmly against the wall of the ship." She obeyed.

"Now when I count three, shove off violently, and pray that we're
going straight. Are you game?"

She stiffened; then, very slowly, "All right; start counting."

"Good girl," Grant said approvingly. "One--two--th-r-ee-ee!"

They flexed their legs in perfect unison. And shoved off.

* * * * *

Out into the blackness of space they shot, lost to all sense of
motion: yet the hull of the space-flier, dimly gleaming in the thin
light of the far off sun, retreated from them with terrifying
swiftness.

They were alone in space! It was an uncanny, a horribly helpless
sensation. All about them was infinity, a vast void out of which
peered at them the cold, unwinking stars. They were like swimmers in
mid-ocean, without even the buoyant feel of the salt water to comfort
them.

Nona's grip on Grant's arm was agonizing in its intensity.

"Scared?" Grant queried.

"A--a little," she admitted; "but don't bothe