p won't take you more than three
weeks, including stopovers."

"I see," said Turnbull. "I haven't made up my mind yet. I'll let you
know."

"Very well, sir. The _Stellar Queen_ leaves on Wednesdays and the
_Oriona_ on Saturdays. We'll need three days' notice."

Turnbull thanked the clerk and headed toward the big doors that led out
of Long Island Terminal, threading his way through the little clumps of
people that milled around inside the big waiting room.

He hadn't learned a hell of a lot, he thought. He'd known that Duckworth
had gone to Mendez, and he already had the Hotel Byron address. There
was, however, some negative information there. The last address they had
was on Mendez, and yet Scholar Duckworth couldn't be found on Mendez.
Obviously, he had not filed a change of address there; just as
obviously, he had managed to leave the planet without a trace. There was
always the possibility that he'd been killed, of course. On a thinly
populated world like Mendez, murder could still be committed with little
chance of being caught. Even here on Earth, a murderer with the right
combination of skill and luck could remain unsuspected.

But who would want to kill Scholar Duckworth?

And why?

Turnbull pushed the thought out of his mind. It was possible that
Duckworth was dead, but it was highly unlikely. It was vastly more
probable that the old scholar had skipped off for reasons of his own and
that something had happened to prevent him from contacting Turnbull.

After all, almost the same thing had happened in reverse a year ago.

Outside the Terminal Building, Turnbull walked over to a hackstand and
pressed the signal button on the top of the control column. An empty cab
slid out of the traffic pattern and pulled up beside the barrier which
separated the vehicular traffic from the pedestrian walkway. The gate in
the barrier slid open at the same time the cab door did, and Turnbull
stepped inside and sat down. He dialed his own number, dropped in the
indicated number of coins, and then relaxed as the cab pulled out and
sped down the freeway towards Manhattan.

He'd been back on Earth now for three days, and the problem of Scholar
James Duckworth was still bothering him. He hadn't known anything about
it until he'd arrived at his apartment after a year's absence.

* * * * *

The apartment door sighed a little as Dave Turnbull broke the electronic
seal with the double key. Half