"All right," he said suddenly, "I'll bargain with you. You've done me a good turn and it deserves a payment. I'll help you get your metal." He grinned ruefully. "I guess I couldn't do anything else."
"It makes it easier this way," I said. I smiled to myself. I was telling him the truth, but not all of it. Nor did I trust him. There was fear and hatred in his lower centers, and a formless feeling in his upper levels that he could outsmart any damn lizard that ever lived. He didn't realize that I could read his surface thoughts.
"Just remember," I said, "I can control you completely, if necessary, and pick your brain for data whether you wish it or not. And forget those ideas of informing your authorities about us. Except with your mate you cannot communicate to anyone about us. There's a basic block in your brain that will result in irreversible mental damage if you try."
This last was not quite the truth. But I hoped that by establishing fear I would prevent talk. "Now find us samples of the metal I want." I withdrew and went back to scanning.
"What was going on there?" Edith said. "You were talking to empty air. And why did you cut yourself?"
"It was one of our reptilian friends," Don said. "Like I thought, they're right with us—every way. He's a weird sort. Wants to trade health and knowledge for tin."
"Tin?"
"Yeah. At least I think it's tin. His description of the metal fits. They use it instead of rocket juice."
"But that knife—your arm?"
"Look. No cut—no blood. That's one of the things they did to us. We've got puncture-proof skin."