122
DOCS.
110, 111
AUGUST
1915
will
cost
you
a
bit
more
than
400
M,
which
you
must
pay immediately
in Deventer.
The
war
makes
the
matter
much dearer.
The
bill
will
be issued to
me as well,
and
I
am
going
to
check
whether
everything
is
in order. The
mover
is
Franzkowiak,
83
Uhland
St.[4]
No
furniture
vans were
used,
but
everything
was
packed
in
crates
instead,
because
a van
would have
incurred
great
expense owing
to
the
war.
I
have
just paid
the
taxes for
you
(19.95 M);
I
am enclosing
the
receipt.
The
booksellers’
bill
you
mentioned has also
arrived,
but
has not
yet
been
paid
by
me.
I
am
curious
about the
experiments.[5]
Describe them
to
me
please
in
a
letter,
also
mentioning
the detours
and difficulties.
I
am
feeling quite
fine;
at
Rügen
I recuperated
well,[6]
particularly
after
making
the
tough
decision
to
give up
smoking
entirely.
At
the
end of
June-beginning
of
July
I held
six
detailed lectures
at Göttingen
on
general
relativity
theory.
To
my
great
delight
I
succeeded in
convincing
Hilbert
and Klein
completely.[7]
I
have not found
out
anything
new
of
consequence
re-
cently;
I
have
even
put
aside
the
attempt
to
verify
our
effect
in
a new
way
because of
the substantial
optical
hurdles.[8]
At
the
end of
the month
I
am
going
to
Switzerland to
see
my
children
& friends,
no
small
undertaking
in these times.
With
best wishes for
your
new
position
in
life,
and
affectionate
greetings,
yours,
A.
Einstein.
D[ear]
de Haas.
I
am
very glad
for
you
that
you
have
preferred
a
settled
teacher’s
career over
a
restless existence in
industry
and
city
life.
It
is
more
pleasant
for
you
all
and healthier
for
your
children.
111. To Paul Hertz
[Berlin,]
22 August
[1915][1]
Dear Mr.
Hertz,
He
who has
wandered
aimlessly
for
so
long
in
the
chaos of
possibilities
under-
stands
your
trials
very
well.
You do
not
have
the
faintest idea
what
I
had to
go
through as
a
mathematical
ignoramus
before
coming
into this
harbor.
Inciden-
tally, your
idea
is
very
natural
and would
by
all
means
be worth
following up,
if
it could be carried
through
at
all,
which,
based
upon my experiences
gathered
during
my wayward wanderings,
I
doubt
very
much.
Given
an
arbitrary
manifold
of 4
dimensions
(given guv(xo)).
How
can one
distinguish
a
coordinate
system
or
a
group
of
such?[2]
This
appears
not
to
be
possible
in
any way simpler
than the
one
chosen
by me.[3]
I
have
groped
around