ctics he was by no means a second-rate
scientist. Which was why he had gained his position at Southwestern
Tech in the first place. He refused to work directly for the government
(no sense of humor, just initials, he said) but this way he could at
least be called upon for consultation at the nearby Air Force
Development Center, just at the foot of the mountains to the west.

Now the AFDC, as it was called, didn't advertise what sort of thing it
was developing--but everybody knew that Lyman Dane was an expert on
reactive propulsion of rocket motors. He could tell you--and frequently
would without being asked--exactly what mass ratio, nozzle diameter and
propulsive velocity would be needed for the first trip to the Moon. He
knew how many hours a round trip would take, both for landing there or
merely circling the body of the satellite.

He had the courses to Mars and Venus thoroughly charted--but considered
a trip to Jupiter somewhat impractical. So, what with Dane's presence
and the mysterious white streaks that so often shot up into the sky like
fuzzy yarn from the AFDC base, it wasn't hard to guess what was going
on.

Nevertheless Professor Dane was surprised and somewhat offended when the
young man from the Federal Bureau of Investigation came to call on him
one afternoon. And the worst part of it was that the young man didn't
have much sense of humor.

"As you know, sir," the young man said, "we've been sighting and
tracking these unidentified objects in the sky. You must have read about
those they chased near Atlanta yesterday."

"Ah," said Professor Dane. "Martian through Georgia, no doubt."

The young man stared at him blankly. He seemed to Professor Dane one of
the most nondescript young men his eyes had ever beheld. He had a
clean-shaven, pleasant face without exactly being handsome and his eyes
were sincere and mild. He wore a neat gray tropical worsted suit and an
unobtrusive tie. He was about thirty. Professor Dane supposed that all
this was an advantage in his profession.

The young man went on--earnestly. "Without forming any theories about
these things we've been asked to take certain precautions. I don't know
whether they suspect a hostile power, or what. That's not my job. At any
rate I've been given the responsibility of instituting certain security
techniques. You do after all, sir, have access to and knowledge of
considerable classified information."

This lad reminded him somewhat of his old