It was a huge, vault-like cavern, with glowing roof high over our heads, and we were about twenty feet above its lower level, with a narrow, steep ramp leading down from near us. I saw that it was a weird, dim grotto, lurid with swaying, prismatic glows of colored radiance, and throbbing, humming with a myriad mechanical voices. Distant railed terraces held frameworks of metal, where opalescent tubes were glowing. Beams of light-radiance seemed to carry the power from one strange mechanism to the next, like wires connecting them in series. No Lei, no ordinary Radak, and certainly least of all us Earthmen, could by any chance have understood the scientific details of what we were seeing.
I recall there was a convergence of beams, high up in mid-air at the center of the cavern, where a shower of tiny electrolyte sparks glittered like a fountain of pyrotechnics. And out of it a narrow concentrated beam of violet-purple glow shot upward to a grid in the ceiling—the gravitational force, doubtless, which from there was conducted to some point above where it was hurled into Space.
How long I stared, awed, I have no idea. Then I was aware of Taro beside me, whispering, "It is the Great Mind who is down there. He has just come into sight—down by that yellow glow."
The floor of the cavern held a dozen or more of the huge mechanisms, and in the center of them there was a throbbing space that seemed to hold the controls of all these intricate machines. Down there in the weird glow we could now see the lone figure of the ancient Radak leader—shriveled and bent, he moved around, occasionally reaching to shift some lever or make some adjustment.
"He must not see us coming!" Taro whispered. His voice was tense. And on his face now as the multi-colored glow bathed it, there was unmistakable terror. This young Lei, like all his people, born and bred to fear the dominance of the Great Mind—to attack that little figure, to Taro was almost unthinkable. Taro had planned this; dreamed of it. But faced with it now, there was only terror sweeping him, so that had he been here alone, easily he could have turned and fled.
Shorty and I had no such inhibitions.
"What in the devil," Shorty murmured. "He's got a Radak-gun—sure, I've no doubt of it. We've got to duck that. But once I get close to him—" Shorty's gesture with his knife was significant.
For minutes more we tensely waited. Then we got down the ramp without being seen, and on the lower floor we crouched between two of the giant whining machines.
"Easy now!" I whispered. "You two—keep behind me—"
I held the Radak-gun in my hand. We waited another moment; then ducked forward and crouched again, behind a great glowing mechanism through which two beams of colored light were passing. We were only some twenty feet from the leader now. Close enough for my shot, or for us to rush him. He was bending down over a glowing dial. Green light from it streamed upward, bathed his weird mummy-like countenance so that suddenly he seemed like some horrible ghoul intent upon a task diabolic, gruesome.