“Wow.” Colin didn’t need a calculator to do the math. “So this eruption was a heck of a lot bigger than either one of those.” By himself or with his colleagues, he was as foulmouthed as any other policeman. He didn’t like to swear in front of women, though. It wasn’t the only reason he often felt like a dinosaur these days.

“Right,” Kelly said. “But this one went off 1.3 million years ago, too. Only sixty-seven cubic miles that time.”

“Only,” Colin echoed. The word seemed to hang in the cold, moist, sulfurous air.

“Only,” she repeated. “ ’Cause it went off 2.1 million years ago, too, and that was the big one. Something like six hundred cubic miles of junk-enough to bury California twenty feet deep. For real, the ash reached from the Pacific to Iowa and from Canada to Texas.”

There was a thought alongside which even a hangover didn’t seem such a big deal. Colin did some more math in his head. “Um, 2.1 million years ago, 1.3 million years ago, 640,000 years ago… Seems like it’s about due. Is it?”

“Nobody knows,” Kelly answered. “And even if it is about due, that might mean it’s ten thousand years away instead of a hundred thousand. Or it might not. But people here and people back in Berkeley don’t like the way the Coffee Pot Springs dome is bulging all of a sudden.”

“What would it be like,” Colin said slowly, “if it did go off for real? I mean, the way it did the biggest time?”

He wondered if she’d say it would be indescribable. But she didn’t: “Take Rhode Island. Blow out lava and ash all around the edges. Then drop it half a mile-maybe a mile-straight down onto molten rock.” She cocked her head to one side, waiting to see what he’d say to that.

What he said was, “Best thing that could happen to the lousy place.”

“Huh?” Whatever she’d expected, that wasn’t it.