“Dan had begun working his way around the room starting at the food wall. "Here's a little wheel to twist" he said, and an instant later, "Genna, it has water in it. Good sweet water. And when you twist the wheel, it stops and starts." And a moment later, "A little room with a privy! But" echoing noises. "Oh," he said, sounding elated, "when you press a handle, water wahses the inside of the privy. You should see this!”