"We sell memory drugs," she said. "Vasopressins, carbolines, endorphins. Stimulants, tranquilizers. Laughers, screamers, shouters, you name it. If there’s a market for it, the Nephrine black chemists can make it. If we can’t synthesize it, we’ll filter it from tissue. Anything you want. Anything you can think of." She lowered her voice. "We’re friends with Them, you know. The ones beyond the Wall. They think the world of us."