A MOONLESS sky hung above them as they swung over the dark and jungle-engulfed deserted city of Tucson, a sky blazing with the clarity of desert stars, and to the south and west shot through with the beams of great searchlights. Flying at a lofty altitude to avoid contact with drifting globes or betrayal of their coming with no lights showing aboard their craft save those carefully screened and focused on the instrument board, it was hard to realize that the fate of America, perhaps of the world, hung on the efforts of two puny individuals.
Everything seemed unreal, ghost-like, and suddenly the strangeness of it all came over Talbot and he felt afraid. The noiseless engine made scarcely a sound; the distant rumble of gunfire sounded like low and muttering thunder. They had come by way of Tucson so as to pick up a ten-gallon tube of concentrated explosive gas at the military camp in the Tucson mountains.
"This gas," the general had assured them, "has been secretly developed by the chemical branch of the War Department and is more powerful than TNT or nitro-glycerin. It is odorless, harmless to breathe and exploded by a wireless-radio device."
He had 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 nothing but a nightmare.