DOCS. 241-243 DECEMBER 1910-JANUARY
1911 171
my
theoretical
or
Perrin's
empirical
result
must
be
wrong.[7]
I
am
curious
how
the
thing
will be
resolved.
The riddle of radiation
will not
yield.[8]
On
the other
hand,
several additional
things
can
be
derived
indirectly
from
Planck's
formula.[9]
Meyer
is
again doing very
interesting
experiments
on
Fy
rays.[10]
But,
in the
main,
the secret
remains
unsolved.
I
wish
you
a
happy
New
Year,
and
may you
free
yourself
of Lenard
very soon.[11]
With
best
regards,
your
A.
Einstein
242.
To Heike
Kamerlingh
Onnes
Zurich, 31
December
1910
Highly
esteemed
Colleague:[1]
You
made
me
very
happy by sending me
the
extremely
important publications
of
your
laboratory. I
thank
you
for
that
with all
my
heart.
As
soon as
I
have
some
time,
I
will
carefully study your
investigation on opalescence.[2]
It
seems
already
to
contain the
material
for
a
quantitative test
of the formula that
I
put
forward in
accordance
with
Smoluchowski's
theory.[3]
Simultaneously
with this
letter
I
am
sending
you
reprints
of
my
papers.
In
about
a
month's
time
I
will have the
extraordinary pleasure
of
getting
acquainted
with
you
and
your highly
esteemed
friend,
Prof.
Lorentz;[4]
for
at
that
time
I
will deliver
a
lecture
to
the Leiden
Student
Association.[5]
Thanking
you
once
again,
I
remain
yours very truly,
A.
Einstein
243.
To
Ludwig
Darmstädter
Zurich,
2
January 1911
Highly
esteemed
Colleague:[1]
I have
not sent
you
for such
a long
time what
you
requested
because
I
did
not
know
what
I
am
really
supposed
to send. Is the
purpose
of the
collection
to
offer
material
for
comparative
studies of
handwriting?[2]
Is it
of
any
interest
what
is
written
on
the
paper?
Be
that
as
it
may,
if
you
can
use
the enclosed
paper[3]
for
your
purposes,
then
please
take
it.
But if
something
else
is desired,
then
please
send
me more specific
instructions.
Respectfully
yours,
A.
Einstein