Mists of Dawn (89 page)

“A
little
magic
of
my
own,”
he
explained
to
Tlaxcan, who
did
not
laugh
at
him.
He
had
seen
the
results of
Mark’s
magic
before.

With
the
pointed
end
of
a
rock,
Mark
carefully sketched
a
jet
aircraft
in
red
dye.
He
took
his
time, and
made
it
accurate
enough
so
that
its
identity
was unmistakable.
Underneath
that,
he
slowly
lettered
a famous
equation:
E
=
MC
²
.
This
was
the
formula worked
out
by
Albert
Einstein,
to
the
effect
that
energy equaled
mass
multiplied
by
the
square
of
the
speed of
light,
an
idea
that
was
instrumental
in
the
development
of
atomic
energy.

When
he
had
finished,
Mark
took
the
rock
and
very carefully
placed
it
behind
a
large
boulder
high
on a
ledge
in
an
out-of-the-way
corner
of
the
cave.
He smiled
to
himself
when
he
had
finished,
knowing
that he
now
had
proof
of
a
sort,
in
case
he
should
ever need
any,
that
he
had
actually
been
back
in
space-time
to
the
land
of
the
Danequa.
He
started
on
toward the
entrance
of
the
cave
with
Tlaxcan.
He
could
tell them
about
that
stone,
and
he
could
take
them
to
it, and
there
it
would
be,
fifty-two
thousand
years
old with
a
drawing
of
a
jet
plane
and
one
of
Einstein’s equations
on
it.
Of
course,
everyone
would
claim
that it
was
a
fake—but
then
you
never
could
prove
anything
to
people
who
had
decided
in
advance
not
to believe
your
evidence.

What
would
happen,
he
wondered,
if
some
anthropologist
or
archaeologist
dug
up
that
stone
before
he got
back
to
it?
He
knew
for
certain
that
it
hadn’t
been discovered
before
he
left
in
the
space-time
machine in
1953,
but
what
about
after
that
if
he
never
got
back? He
could
well
imagine
the
absolute
dumfounded
confusion
of
the
man
who
found
that
stone
associated
with Cro-Magnon
culture!
Even
with
his
layman’s
knowledge
of
the
profession,
Mark
strongly
suspected
that the
hypothetical
anthropologist
would
promptly
bury the
stone
again
and
forget
about
it,
rather
than
attempt to
prove
that
his
find
was
a
genuine
one
and
that someone
had
evidently
known
about
Einstein
and
jet airplanes
during
the
Ice
Age.

As
they
walked
back
out
of
the
limestone
caverns into
the
open
air
and
saw
the
preparations
for
the war
party
all
around
them,
Mark
was
strongly
tempted to
try
to
tell
Tlaxcan
something
about
himself
and where
he
had
come
from.
He
gave
up
the
idea,
however,
after
a
moment’s
reflection.
There
were
no
words in
the
Danequa
language,
nor
concepts
in
the
Danequa mind,
by
which
he
could
explain
the
space-time
machine
and
the
world
of
the
future
to
Tlaxcan.
The cultures
and
customs
and
beliefs
they
had
each
known since
childhood,
stood
between
them—and
yet
Tlaxcan was
one
of
the
best
friends
that
he
had
ever
had,
and