646
DOCS.
620,
621
SEPTEMBER
1918
applies
with
regard
to
the
Lorentz
contraction
as
well.
You
unfortunately stopped
just
before
the
doubly
underlined
question
in
§23:
Which
of
the
two rods must
be
made shorter?[9]
This
question
was
my
starting
point
for all
the
considerations.
It and the contradiction
regarding
the standard
clocks,
which
on
the
one
hand
define
the unit
of
time,
on
the other
allow
the
ascertainment
of
the
lapsing
of
a
differing
number of
units
of
time,
must
continually
reawaken
doubts
in
any
impartial
person.
But
I do
not want
to
pester
you anymore
right
now; once
it
is
in
print,
it
will
obviously
be
more
comfortable to read and
one or
two
details
will
have been
improved.
As
concerns
the
manuscript,
please,
if it does
not
cause
you
too much
effort,
it
to
me
in
the
same
form
that
I
had
sent
it
out.
Otherwise,
I
ask
you simply
to
keep
it
but
not
to show
it
to
anyone. Nobody
was
ever encouraged by
me
to ask
you
for
information,
and
I
am
sorry
if
you
were
inconvenienced.
I
am sending you a
transcription
of
your
last
derivation
shortly,[10]
so
that this letter
does
not
exceed
the
wartime
standard.
In
principle,
this derivation
is,
of
course,
identical with
that
in Laue’s
book, p.
38,
except
that
one
ray
takes
the
place
of the
entire
wave.[11]
I would have
had
a
great
deal
more
to
say,
but
for
today space
only
remains
to
thank
you
very
much
once again
for
your
effort. Cordial
regards, yours,
F.
Adler.
621. To
Paul and Maja Winteler-Einstein, and
Pauline Einstein
[Berlin,
23 September
1918]
My Dears,
Your
telegram
of
yesterday
awakes
me
from
my
indolent
slumber and reminds
me
that
you
all don’t know
yet
that
I’m not
coming
to Switzerland at
all,
right
now.[1]
The
reasons,
the
flu
notwithstanding,[2]
are
the
following.
As
you know,
I received
a
very
attractive
call to Zurich and at first
didn’t
know
what
I should do.
Well,
although
I
declined
the
appointment, I
offered to
the
Zurichers to
lecture
there
twice
a
year
for
a
month each
time,
in order thus
to show
my appreciation.[3]
It’s still
not
certain
whether
something
will
come
of
it,
but it
is
very probable.
Prof.
Meyer
in Zurich
thought
I
should start
lecturing
there
in
February.[4]
So
it
is
understandable
if
I
don’t travel to Switzerland
now,
because
it
could otherwise become
too
much
of
a
good thing.
I
would be
very
pleased
if
something
came
of it.