Telt handed him the magnifier and tape. "Look at that—recording tape from my scintillation counter. Red verticals are five-minute intervals, the wiggly black horizontal line is the radioactivity level. All this where the line goes up and down, that's when we were driving out to the attack. Varying hot level of the rock and ground."
"What's the big peak in the middle?"
"That coincides exactly with our visit to the house of horrors! When we went through the hole in the bottom of the tower!" He couldn't keep the excitement out of his voice.
"Does it mean that...."
"I don't know. I'm not sure. I have to compare it with the other tapes back at base. It could be the stone of the tower—some of these heavy rocks have got a high natural count. There maybe could be a box of instruments there with fluorescent dials. Or it might be one of those tactical atom bombs they threw at us already. Some arms runner sold them a few."
"Or it could be the cobalt bombs?"
"It could be," Telt said, packing his instruments swiftly. "A badly shielded bomb, or an old one with a crack in the skin, could give a trace like that. Just a little radon leaking out would do it."
"Why don't you call Hys on the radio and let him know?"
"I don't want Granddaddy Krafft's listening posts to hear about it. This is our job—if I'm right. And I have to check my old tapes to make sure. But it's gonna be worth a raid, I can feel that in my bones. Let's unload your corpse." He helped Brion with the clumsy, wrapped bundle, then slipped into the driver's seat.
"Hold it," Brion said. "Do you have anything in the med box I can use for Lea? She seems to have cracked. Not hysterical, but withdrawn. Won't listen to reason, won't do anything but lie there and ask to go home."