“That black stuff could be dust, thrown up by the quake. The rock shears, the water vaporizes… You get a build-up of electricity…” She glanced around the campus. “These buildings — they conform to the California building code. Right?”

“This isn’t California.” Cecilia looked confused. “How would I know?”

“Well, they look like tilt-up construction to me.”

“Is that bad?”

The thunder was replaced by a low rumbling noise overlaid by a crackle, a series of short bangs that sounded like gravel on a tin roof.

Joely listened intently to the low-frequency rumble, fascinated. She knew what that was. She was hearing the shortest-wavelength seismic waves, listening to the vibration of the Earth itself. The longest waves, with a period of an hour or so, corresponded to the whole Earth’s resonant frequency, and were much too low-frequency to hear.

The planet was ringing like a bell.

Now, above the storm, there was a strange cloud formation. Something like a smoke ring, Joely thought, a loose band of fluffy white. Maybe that was the acoustic pressure wave, rising up towards the stratosphere. The satellites would detect it later, a displacement of the atmosphere’s layers by a mile or more.

Now Cecilia was starting to sound nervous. “What’s going on? Are we safe here?”

“I don’t know. That storm front must be hundreds of miles long.”

“But we’re safe, right?”

Of course not. “…Yes. I guess so.”

Cecilia was silent.

On impulse, Joely reached out and took Cecilia’s hand.

Joely thought of the cat. Animals knew how to brace themselves like that, standing with their legs apart, cross-ways to the shock.

That cat is smarter than I am, she thought.

Now there was movement.

A couple of the pine trees at the edge of the campus tipped up, locking their branches together like clasping hands. When they sprang apart, their trunks cracked, and burst into showers of matchwood.

Another line of trees, closer, popped out of the ground, roots and all, like wooden rockets.

Incoming, Joely thought.

“Holy shit,” said Cecilia.

…And then it hit.

It came in a second, without warning. The floor just disappeared from beneath her, and she was thrown into the air — like a kid in her father’s arms — her nose was inches from the ceiling… Then she fell, landing heavily on her back.

An instant of stillness. Something falling to the floor with a soft explosion, maybe Cecilia’s pc monitor. Glass, she thought, and she closed her eyes.

She’d had Cecilia’s hand wrenched out of her grasp in that first moment. She opened her mouth to call her.

Slam, under her back.

Again she was thrown into the air.

She landed with a grunt, on her front this time, mercifully clear of furniture.