Then and then only he spoke to Robur for the first time. "The desert. Recall you, Rob, the morn of the first motur in Himyra, when we drove into it from Himyra's walls, and Lakkon's gnuppas bolted, and I touched the hand of Naia of Aphur first?"
"Aye." Robur turned. Himyra was receding as the blimp followed her new course. "By—Zitu—we are aiming for it again."
Croft nodded. "It is in my mind to try first the liquid fire upon its scanty vegetation, where it can do small harm."
And after that he waited until they flew above a comparatively level tract of country, covered by a low-growing shrub, that throve on scanty moisture, before he stationed himself at the spraying device and opened the valve of the flask.
Far below, the scrub blossomed suddenly into tiny points of color like swiftly opening flowers—that grew, expanded, ran together in patches and lines of quivering light, until the whole mass of vegetation vanished, blotted out beneath a leaping sea of flame. A moment before it had lain there unchanged, as it and the desert had lain practically unchanged for years, and now it was a seething, smoking, blazing thing, sinking down in a red destruction unloosed upon it from the skies.
Croft closed the tank. "Back to Himyra," he cried and turned a set face to Robur, to find his features pale and rigid, his eyes narrowed as though the vegetation beneath him, writhing in a swift dissolution, were to his imagination the bodies of men and women caught beneath a rain of death inside a city's walls.
"It is finished, Rob," he said, speaking in a voice that quivered tensely. "As soon as the fliers are trained we go north."
Croft nodded. The strange intoxication of success was upon him.
"Ere night," he said, "we test the others." And then sinking his voice for no ears save Robur's. "And tonight I shall look into Naia of Aphur's eyes and tell her we are well-nigh prepared."