“Well, yeah.” Colin hated being predictable. Sometimes he was-sometimes everybody was-but he still hated it.

“Don’t worry. People do that. It’s what the thing is there for, you know?” Kelly said. That made him feel worse, not better. Then she asked, “After you looked at all the stuff there, what did you do?”

“I had lunch.” He’d testified in court too often to be anything but literal-minded.

This time, she stuck out her tongue at him, which made her look about twelve. “You sound like a cop, all right. Let’s try it again. What did you do after lunch? Did you drive up to the Black Sand Basin?”

“Yes, Honor,” Colin answered, deadpan.

“Okay,” Kelly said in now-we’re-getting-somewhere tones. “You can see the caldera wall-the edge of what fell in the last time the supervolcano erupted-really well from there. I think they’ve got a sign about it, too. Do you remember that?”

“Uh-huh. As a matter of fact…” Colin took the camera out of his jacket pocket, powered it up, and thumbed back till he found the pictures he wanted. One was of the sign she’d mentioned. The other was of the caldera wall itself: an almost vertical cliff of solidified lava, several hundred feet high, with lodgepole pines growing up out of it here and there.

Kelly leaned forward to look at the photos in the viewfinder. She nodded. “That’s it, all right. That’s what’s left from the last time it went off, I mean, maybe 640,000 years ago. It shot out about two hundred and forty cubic miles of ash and lava and rock-say, a thousand times as much as Mount St. Helens.”

“How about compared to Krakatoa?” Colin asked. “Or the earlier one in the 1800s-I forget its name, but the one that made the Year without a Summer?”

“Mount Tambora.” She beamed at him. People did that when you surprised them by knowing more than they’d expected about what they were interested in. “That was about thirty-five cubic miles. Krakatoa was only a squib next to it: six or seven cubic miles.”