"The night of our skyfall," Samshow said.

"Right. We place the time at about eight-twenty P.M. Right?"

"That's our time, within ten minutes," Sand acknowledged.

"Okay. Not an earthquake per se. Not a fault slide. More like a nuclear detonation—and yet, not. We get a PcP—reflection off the outer core—in Beijing and reflections from the P260P and P400P in Colorado, then we get P-prime-P-prime waves at the LASA in Montana. Not only that, but we get persistence in the high-frequency P-waves. No Love or Rayleigh surface waves, just body waves. No immediate shear waves. Just compression waves and lots of really unusual microseisms, like something burrowing. Right in the Ramapo Deep. What could that be?"

Sand grinned like a small boy, mischievous. "Something that weighs perhaps a hundred million tons."

"Right," Kemp said, mirroring his grin. "So let's talk crazy. Anything that masses in at ten to the eighth metric tons, strikes the ocean like a mountain. But all you get is a minor squall. So it didn't transfer much of its energy. Very small profile. Just shot right through, lost a tiny, tiny percentage of its velocity to the water, maybe some heat as well. Something less than a meter wide."

"That's ridiculous," Samshow said.

"Not at all. A plug of superdense matter, probably a black hole. Hitting the ocean nearby, falling to the bottom of the Ramapo Deep, voilà! Burrowing."

"Incredible," Sand said, shaking his head, still grinning.

"All right. We both have anomalies. My people have a nuclear event profile that isn't, and you have a jag." Kemp lifted his drink. "Here's to shared mysteries."

Sand had his electronic notebook out and was busy entering figures. "A black hole that size would be a strong source of gamma rays, right?"

"I don't know," Kemp said.

Sand shrugged his shoulders. "But it's so dense and so small it falls directly to the center of the Earth. Actually, it bypasses the center because of Coriolis, and bounds up the other side. There's very little effective drag. It's just like passing through thin air."

Kemp nodded.

"When it reaches the core, it's traveling about ten kilometers per second. Can you imagine the shock wave coming off that thing? The whole Earth would ring like a bell—your microseisms. The heat released would be incredible. I don't know how to calculate that . . . We need somebody conversant in fluid dynamics. Its period— the time it takes to 'orbit' in its closed loop around the center of the Earth—would be about eighty, ninety minutes."

"Wouldn't whatever sound it makes get lost in background noise?" Samshow asked, feeling years out of date.

"Oh, we're hearing it, all right," Kemp said. "Chattering like an imp. Can I borrow your notebook?"