D O C U M E N T 2 6 6 O C T O B E R 1 9 2 1 1 6 9
the simplest solution in the technical issue. If progress can be made through an
improvement of the iron, all the better. If the iron is not available on the market,
Count Arco would surely give us
some.[4]
As concerns the magnetic experiment, I do consider the static measurement
solution for the preferable and believe that with a short-circuited coil the eddy
currents won’t disturb anymore. The main disadvantage of the induction method
for the measurement of weak fields is the Earth’s magnetic field. In any case, it
would be nice if the gentlemen would write me about their project before they carry
it out so that as much effort is spared as
possible.[5]
On the 15th I am traveling with my boy to Bologna in order to demonstrate my
sauerkraut-Italian
there.[6]
The grandsons of Dante will have something to be sur-
prised about! Then I have to go to Holland for a few more weeks, so the experimen-
tal and theoretical collaborations here will have to stay idle for over a month
again.[7]
But there are interesting things in Leyden,
too.[8]
Cordial regards also to your wife, yours,
A. Einstein.
264. From Erich Wende[1]
Ministry of Culture, 4 Unter den Linden, Berlin W 8, 11 October 1921
[Not selected for translation.]
265. To Friedrich Vieweg
Berlin, 12 October 1921
[Not selected for translation.]
266. From Hans Reichenbach
Stuttgart, 5 Knosp St., 12 October 1921
Dear Mr. Einstein,
I continued to think about the problem of how one can define points mutually at
rest by light
signals[1]
and would like to inform you about my results. My Defini-
tion 4 is not
unique;[2]
a calculation error had slipped in. But an addendum can
make it clear and that is what I would like to write you about.