iously.

"I know. I drove her back to the station. That was when--when we
quarreled."

"But why? About Einstein? That's silly."

"She wanted me to give it up here, and go in with her father in his
Wall Street brokerage business. The old gent is willing to take me,
and make a business man of me."

"Why, I couldn't run the business without you, Charlie!"

"We talked about that, Hammond. I don't really do much of the work.
Just play around with the mathematics, and leave the models and
blueprints to you."

"Oh, Charlie, that's not quite--"

"It's the truth, right enough," he said, bitterly. "You design
aircraft, and I play with Einstein. And as you say, a fellow can't eat
equations."

"I'd hate to see you go."

"And I'd hate to give up you, and our business, and the math. Really
no need of it. My tastes are simple enough. And old 'Iron-clad'
Randall has made all one family needs. Virginia's not exactly a
pauper, herself. Two or three millions, I think."

"And where did Virginia go?"

"She took the _Valhalla_ yesterday at San Francisco. Going to join her
father at Panama. He cruises about the world in his steam yacht, you
know, and runs Wall Street by radio. I was to telegraph her if I'd
changed my mind. I decided to stick to you, Hammond. I telegraphed a
corsage of orchids, and sent her the message, 'Einstein forever!'"

"If I know Virginia, those were not very politic words."

"Well, a man--"

* * * * *

His words were cut short by a very unusual incident.

A thin, high scream came suddenly from above our neat stuccoed hangars
at the edge of the white field. I looked up quickly, to catch a
glimpse of a bright object hurtling through the air above our heads.
The bellowing scream ended abruptly in a thunderous crash. I felt a
tremor of the ground underfoot.

"What--" I ejaculated.

"Look!" cried Charlie.

He pointed. I looked over the gleaming metal wing of the _Golden
Gull_, to see a huge cloud of white sand rising like a fountain at the
farther side of the level field. Deliberately the column of debris
rose, spread, rained down, leaving a gaping crater in the earth.

"Something fell?"

"It sounded like a shell from a big gun, except that it didn't
explode. Let's get over and see!"

We ran to where the thing had struck, three hundred yards across the
field. We found a great funnel-shaped pit torn in the naked earth. It
was a dozen yards across, fifteen feet deep