Lest Darkness Fall

            TANCHEDI TOOK HIS HANDS off
the wheel again and waved them. "— so I envy you, Dr. Padway. Here in Rome
we have still some work to do. But
pah!
It is all filling in little
gaps. Nothing big, nothing new. And restoration work. Building contractor's
work. Again,
pah!
"

            "Professor
Tancredi," said Martin Padway patiently, "as I said, I am not a
doctor. I hope to be one soon, if I can get a thesis out of this Lebanon
dig." Being himself the most cautious of drivers, his knuckles were white
from gripping the side of the little Fiat, and his right foot ached from trying
to shove it through the floor boards.

            Tancredi snatched the wheel
in time to avoid a lordly Isotta by the thickness of a razor blade. The Isotta
went its way thinking dark thoughts. "Oh, what is the difference? Here
everybody is a doc-tor, whether he is or not, if you understand me. And such a
smart young man as you — What was I talking about?"

            "That depends."
Padway closed his eyes as a pedestrian just escaped destruction. "You were
talking about Etruscan inscriptions, and then about the nature of time, and
then about Roman archaeol —"

            "Ah, yes, the nature of
time. This is just a silly idea of mine, you understand. I was saying all these
people who just disappear, they have slipped back down the suitcase."

            "The what?"

            "The trunk, I mean. The
trunk of the tree of time. When they stop slipping, they are back in some
former time. But as soon as they do anything, they change all subsequent
history."

            "Sounds like a
paradox," said Padway.

            "No-o. The trunk
continues to exist. But a new branch starts out where they come to rest. It has
to, otherwise we would all disappear, because history would have changed and
our parents might not have met."

            "That's a
thought," said Padway. "It's bad enough knowing the sun might become
a nova, but if we're also likely to vanish because somebody has gone back to
the twelfth century and stirred things up —"

            "No. That has never
happened. We have never vanished, that is. You see, doc-tor? We continue to
exist, but another history has been started. Perhaps there are many such, all
existing somewhere. Maybe, they aren't much different from ours. Maybe the man
comes to rest in the middle of the ocean. So what? The fish eat him, and things
go on as before. Or they think he is mad, and shut him up or kill him. Again,
not much difference. But suppose he becomes a king or a duce? What then?

            "
Presto
, we have
a new history! History is a four-dimensional web. It is a tough web. But it has
weak points. The junction places — the focal points, one might say — are weak.
The back-slipping, if it happens, would happen at these places."

            "What do you mean by
focal points?" asked Padway. It sounded to him like polysyllabic nonsense.

            "Oh, places like Rome,
where the world-lines of many famous events intersect. Or Istanbul. Or Babylon.
You remember that archaeologist, Skrzetuski, who disappeared at Babylon in
1936?"

            "I thought he was
killed by some Arab holdup men."

            "Ah. They never found
his body! Now, Rome may soon again be the intersection point of great events.
That means the web is weakening again here."

            "I hope they don't bomb
the Forum," said Padway.

            "Oh, nothing like that.
Our
Duce
is much too clever to get us into a real war. But let us not
talk politics. The web, as I say, is tough. If a man did slip back, it would
take a terrible lot of work to distort it. Like a fly in a spider web that
fills a room."

            "Pleasant
thought," said Padway.

            "Is it not,
though?" Tancredi turned to grin at him, then trod frantically on the
brake. The Italian leaned out and showered a pedestrian with curses.

            He turned back to Padway.
"Are you coming to my house for dinner tomorrow?"

            "Wh-what? Why yes, I'll
be glad to. I'm sailing next —"

            "Si, si. I will show
you the equations I have worked out. Energy must be conserved, even in changing
one's time. But nothing of this to my colleagues, please. You understand."
The sallow little man took his hands off the wheel to wag both forefingers at
Padway. "It is a harmless eccentricity. But one's professional reputation
must not suffer."

            "
Eek!
" said
Padway.

            Tancredi jammed on the brake
and skidded to a stop behind a truck halted at the intersection of the Via del
Mare and the Piazza Aracoeli. "What was I talking about?" he asked.

            "Harmless
eccentricities," said Padway. He felt like adding that Professor
Tancredi's driving ranked among his less harmless ones. But the man had been
very kind to him.

            "Ah, yes. Things get
out, and people talk. Archaeologists talk even worse than most people. Are you
married?"

            "What?" Padway
felt he should have gotten used to this sort of thing by now. He hadn't.
"Why — yes."

            "Good. Bring your wife
along." It was a surprising invitation for an Italian to issue.

            "She's back in
Chicago." Padway didn't feel like explaining that he and his wife had been
separated for over a year.

            He could see, now, that it
hadn't been entirely Betty's fault. To a person of her background and tastes he
must have seemed pretty impossible: a man who danced badly, refused to play
bridge, and whose idea of fun was to get a few similar creatures in for an
evening of heavy talk on the future of capitalism and the love life of the
bullfrog. At first she had been thrilled by the idea of traveling in far
places, but one taste of living in a tent and watching her husband mutter over
the inscriptions on potsherds had cured that.

            And he wasn't much to look
at — rather small, with outsize nose and ears and a diffident manner. At
college they had called him Mouse Padway. Oh, well, a man in exploratory work
was a fool to marry, anyway. Just look at the divorce rate among them — anthropologists,
paleontologists, and such —

            "Could you drop me at
the Pantheon?" he asked. "I've never examined it closely, and it's
just a couple of blocks to my hotel."

            "Yes, doc-tor, though I
am afraid you will get wet. It looks like rain, does it not?"

            "That's all right. This
coat will shed water."

            Tancredi shrugged. They
bucketed down the Corso Vittorio Emanuele and screeched around the corner into
the Via Cestari. Padway got out at the Piazza del Pantheon, and Tancredi departed,
waving both arms and shouting: "Tomorrow at eight, then? Si, fine."

-

            Padway looked at the
building for a few minutes. He had always thought it a very ugly one, with the
Corinthian front stuck on the brick rotunda. Of course that great concrete dome
had taken some engineering, considering when it had been erected. Then he had
to jump to avoid being spattered as a man in a Fascist uniform tore by on a
motorcycle.

            Padway walked over to the
portico, round which clustered men engaged in the national sport of loitering.
One of the things that he liked about Italy was that here he was, by
comparison, a fairly tall man. Thunder rumbled behind him, and a raindrop
struck his hand. He began to take long steps. Even if his trench coat would
shed water, he didn't want his new fifty-lire Borsalino soaked. He liked that
hat.

            His reflections were cut off
in their prime by the grand-daddy of all lightning flashes, which struck the
Piazza to his right. The pavement dropped out from under him like a trapdoor.

            His feet seemed to be
dangling over nothing. He could not see anything for the reddish-purple
after-images in his retinas. The thunder rolled on and on.

            It was a most disconcerting
feeling, hanging in the midst of nothing. There was no uprush of air as in
falling down a shaft. He felt somewhat as Alice must have felt on her leisurely
fall down the rabbit-hole, except that his senses gave him no clear information
as to what was happening. He could not even guess how fast it was happening.

            Then something hard smacked
his soles. He almost fell. The impact was about as strong as that resulting
from a two-foot fall. As he staggered by he hit his shin on something. He said
"Ouch!"

            His retinas cleared. He was
standing in the d epression caused by the drop of a roughly circular piece of
pavement.

            The rain was coming down
hard, now. He climbed out of the pit and ran under the portico of the Pantheon.
It was so dark that the lights in the building ought to have been switched on.
They were not.

            Padway saw something
curious: the red brick of the rotunda was covered by slabs of marble facing.
That, he thought, was one of the restoration jobs that Tancredi had been
complaining about.

            Padway's eyes glided
indifferently over the nearest of the loafers. They switched back again
sharply. The man, instead of coat and pants, was wearing a dirty white woolen
tunic.