82
DOCS. 113-115 JULY-AUGUST
1908
the
smallness
of the
forces).
In
my opinion, no objections can
be
raised
against
it from
a
theoretical
standpoint.
I
don't
like
doing
the
calculations for
the
ponderomotive
forces. I
cannot
make
up
my
mind
to
do
them. An intrinsic
cause
of the
difficulty
in
constructing
a
general
formulation
of
the
principle
of
the
equality
of
action and
reaction
for
moving
bodies
consists in
the
fact
that,
in
general,
the
temporal
changes
of
e
and
fi
are
not
rooted
in
explainable
processes
to which
changes
of
energy
and momentum
must
correspond.[11]
All
things
considered,
all of
this
horrible
calculating
will not make
one
any
wiser.
I
haven't
yet
been
able to
think of
a
clear
way
to solve
the
problem.
I have
now
found
a
capable
mechanic here
who
is presently putting together
the
electrostatic
Maschinchen
according
to
my
specifications.[12]
It
should be
ready
in the next
few
days.
I
shall
see
for
myself
what
it
can
do and how
true
the
rumors are
about the
trickiness
of the
contact.
Best
regards
from
your
A.
Einstein
and
let
me
hear
again
from
you
quite
soon.
114.
To
Lucien and
Jeanne Chavan-Perrin[1]
[Miirren,
13
August 1908]
Cordial
greetings
from
our
vacation
from
the
Einstein
family
115.
To Maurice
Solovine
[Mürren, 15 August 1908]
Dear
Solo,
Heartfelt
congratulations
on your
position.[1]
You
wouldn't
believe how
happy
I
am
that
you
are doing
well.
Greetings
from
my
vacation.
Your
Einstein
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