"I can't let you go off into such danger, without me!" she cried, almost hysterical. "I can't!"
The Prince swung a heavy torpedo higher on his shoulders, and strode off over bare gravel toward the low rocky slope of the mountain that lay to northward, faintly revealed in the light of the stars. The other four followed silently. The slender sunship, with the old scientist and his sobbing daughter outside the air-lock, quickly vanished behind them.
With only an occasional cautious flicker of the flashlights the five men picked their way over bare hard ground, among scattered clumps of mesquite. Presently they crossed a barren lava bed, clambering over huge blocks of twisted black volcanic rock. Up the slope of the mountain they struggled, sweating under heavy burdens, blundering into spiky cactus, stumbling over boulders and sagebrush.
When the silver and rose of dawn came in the purple eastern sky, the five lay on bare rock at the top of the low ridge, overlooking the flat, mesquite-covered valley beyond. The valley floor was a brownish green in the light of morning, the hills that rose far across it a hazy blue-gray, faintly tinged with green on age-worn slopes.
Like a string of emeralds dropped down the valley lay an endless wandering line of cottonwoods, of a light and vivid green that stood out from the somber plain. These trees traced the winding course of a stream, the Rio Casas Grandes.
Lying against the cottonwoods, and rising above their tops, were two great spheres of blue, gleaming like twin globes of lapis lazuli in the morning light. They were not far apart, and between them rose a curious domed structure of white, silvery metal.
Each of the five men lifted his heavy metal tube, leveled it across a boulder before him. The Prince, alert and smiling despite the dust and stain of the march through the desert, spoke to the others.
"This little tube along the top of the torpedo is a telescope sight. You will peer through, get the cross hairs squarely upon your target, and hold them there. Then press this nickeled lever. That starts the projectile inside the case to spinning so that inertia will hold it true. Then, being certain that the aim is correct, press the red button. The torpedo is thrown from the case by compressed air, and a positive ray mechanism drives it true to the target. When it strikes, about fifty pounds of Dr. Trainor's new explosive, trainite, will be set off.
"Walker, you and Windsor take the right globe. Smith and Brand, the left. I'll have a shot at that peculiar edifice between them."
Bill balanced his torpedo, peered through the telescope, and pressed the lever. The hum of a motor came from the heavy tube.