I moved into the darkness, not using my black light pencil, but keeping my sensitized glasses on so I could see Herb's if I got close enough.
I reached the spot where we had done the digging. I hesitated, then kept on, toward the spot where Herb and Dotty had been so engrossed that afternoon. In my mind's eye I knew exactly where it was.
My hands explored ahead of me, searching out each stone marker along my path, clinging to it as I passed it, and slipping off as I went on to the next. They were my only contact with reality in this total blackness.
I was thinking, too. I was thinking of what Herb had said about this being a parking area for airsleds back before the earliest known records of man on Earth when this city was alive. He was probably right about it at that. Analysis had shown the presence of copper and aluminum in the top surface of some of the markers that could only be accounted for by some metallic object setting atop each one long ago, and remaining so that molecular and atomic creep could set in, carrying such atoms deep into the surface crystals of the stone.
And I was wondering what it was he hoped to dig up. If it were some sort of weapon it probably wouldn't work after all this time. It couldn't! Or could it? A few things had been pieced together about the ancient Martian civilization. Not much, but enough to be sure that they knew a few things we had never discovered. They had been masters at creating machines with no moving parts. The electronic devices we had found had proven they knew far more about V.H.F. than we did.
I could see what C.I. was aiming at now. We might not even recognize what Herb was searching for. It would be better to let him find it, and get it from him before he could use it. If it was a weapon.
And it probably was a weapon. I was pretty sure his main objective was hidden in the wall in the dome, and that this thing in the cemetery was something that would help him get to that objective.
My thoughts came back to my surroundings. I was less than a dozen feet from where Herb and Dotty should be. I stopped. There was no trace of black light. I held my breath and listened. And I heard the faint scraping of the knife against stone.
I wished fervently that I had a standard C.I. infrascope so that I could see. Steve probably knew more of what was going on than I did. I had counted on watching Herb by his own black light pencil, and he was working in darkness.