showed them how to manipulate the radio device, and explained
that in the metal tube was a tiny chamber from which gas could not
escape, and a receiving-detonating cap. "If you can introduce the tube
into the underground galleries where you suspect the enemy's
headquarters to be, allow the contents to escape for ten minutes, and a
mile distant you can blow the mine and all in it to destruction. And
you needn't be afraid of anything escaping alive," he had added grimly.

Talbot thought of his words as the dark and silent world slid by. He
glanced at the luminous dial of his wrist-watch. Eleven-fifteen. The
moon rose at eleven-twenty-four. He studied the map. High over Mount
Lemmon the craft soared. He touched the army pilot's arm. "All right,"
he said, "throttle her down." Their speed decreased. "Lower."

Swiftly they sank, until the dark bulk of hills and trees lay blackly
beneath; so near as to seem within the touch of a hand. Though he
strained his ears, no alien sound came wafting upward. "Keep circling
here," he directed the pilot. "The moon'll be up in a minute and then
we can be sure of where we are." The pilot nodded. He was a phlegmatic
young man. Not once during the trip had he uttered a word.

The east glowed as if with red fire. Many a time before had Talbot
watched the moon rise, but never under stranger circumstances. Now the
night was illuminated with mellow glory. "Hit the nail on the head," he
whispered. "Do you see that spot over there? To the left, yes. Can you
land us there?"

Without a word the pilot swung for the clearance. It was a close thing,
requiring delicate maneuvering, and only an auto-gyroscope could have
made it without crashing. Hurriedly Manuel and Talbot unloaded their
gear.

"All right," said Talbot to the pilot. "No need to wait for us. If we
are successful, we'll send out the wireless signal agreed on, and if we
aren't...." He shrugged his shoulders. "But tell the General to be sure
and allow us the time stipulated on before undertaking another attack."

Standing there on the bleak hillside, watching the auto-gyroscope run
ahead for a few yards and then take the air, Talbot experienced a
feeling of desolation. Now he and Manuel were alone, cut off from their
own kind by barriers of impregnable jungle. And yet on that lonely
hillside there were no signs of an enemy. For a moment he wondered if
he weren't asleep, dreaming; if he wouldn't soon awake to find that all
this was n