tes and returned with an old, fragile,
almost impossibly delicate-looking book. Alan took it and scanned the
opening page. There were the words he had read so many times: "The
present system of interstellar travel is so grossly inefficient as to be
virtually inoperable on an absolute level."

"Yes, that's the book. I'll take it."

His first stop on his round-the-globe jaunt was London, where Cavour had
been born and educated more than thirteen centuries before. The
stratoliner made the trip across the Atlantic in a little less than
three hours; it took half an hour more by Overshoot from the airport to
the heart of London.

Somehow, from Cavour's few autobiographical notes, Alan had pictured
London as a musty old town, picturesque, reeking of medieval history. He
couldn't have been more wrong. Sleek towers of plastic and concrete
greeted him. Overshoots roared by the tops of the buildings. A busy
network of bridges connected them.

He went in search of Cavour's old home in Bayswater, with the nebulous
idea of finding some important document wedged in the woodwork. But a
local security officer shook his head as Alan asked for directions.

"Sorry, lad. I've never heard of that street. Why don't you try the
information robot up there?"

The information robot was a blocky green-skinned synthetic planted in a
kiosk in the middle of a broad well-paved street. Alan approached and
gave the robot Cavour's thirteen-century-old address.

"There is no record of any such address in the current files," the
steely voice informed him.

"No. It's an old address. It dates back to at least 2570. A man named
Cavour lived there."

The robot digested the new data; relays hummed softly within it as it
scanned its memory banks. Finally it grunted, "Data on the address you
seek has been reached."

"Fine! Where's the house?"

"The entire district was demolished during the general rebuilding of
London in 2982-2997. Nothing remains."

"Oh," Alan said.

The London trail trickled out right then and there. He pursued it a
little further, managed to find Cavour's name inscribed on the honor
role of the impressive London Technological Institute for the year 2529,
and discovered a copy of Cavour's book in the Institute Library. There
was nothing else to be found. After a month in London, Alan moved on
eastward across Europe.

Most of it was little like the descriptions he had read in the
_Valhalla's_ library. The trouble was that the