2 2 8 D O C U M E N T 9 9 A U G U S T 1 9 2 0
effort.[1]
Now, though, I am doubly pleased, first, because everything is finished, in
principle,[2]
so you won’t have to exert yourselves anymore; and second, and par-
ticularly so, because now I have the welcome excuse for coming to Leyden more
often. If all the formalities are settled by the end of October, I shall come at that
time to deliver the inaugural
lecture.[3]
If it should take longer, however, it is all the
same; I shall then simply come correspondingly later. The trip to Christiania was
really nice; the hours I spent with Bohr in Copenhagen were the
finest.[4]
He is a
highly talented and exceptional person. It is a good sign for physics that prominent
physicists are mostly superb people as well. It is also encouraging that, despite the
bad economic situation, interest in science has not diminished here in the least. Col-
loquium and physical society are always eagerly attended. The papers by Aston and
Rutherford were reviewed by Rubens and received with
enthusiasm.[5]
It is good to
see that there are still a few things that have not fallen victim to the political
insanity.
To you and your wife cordial regards from your
Einstein.
P.S. I have now seen the photograms of the cyanogen spectrum by Grebe and
Bachem; they will soon appear in the Zeitschrift für
Physik.[6]
One sees from them
very clearly that nonphotometric spectra must not be used for analysis of line
spectra. Although this paper does not conclusively prove the existence of the red-
shift, it does make it probable.
I am very curious what comments you have about Eddington’s
book.[7]
I actually
have objections only to his position on the boundary conditions (cosmolog. prob-
lem) but know that you will not concur with me in that.
99. From Paul Ehrenfest
[Leyden,] 6 August 1920
Dear Einstein,
Many thanks for your postcard.—It relieves me of a great worry, since I could
not see how I could send the case and bow back to
you.[1]
But please do buy
yourself a really good case and a good bow—just allow me to wait with the pay-
ment until you are here, because at the moment I am hopelessly stranded on the
rocks, without any means of obtaining money for myself directly.
Now to your question about the second
violin.[2]
Provided you can pass it on
without loss, it would probably be the right thing to do, because I really cannot see
how I can get by in the near future without enlarging my debts, and do not want to
owe you more money either.—But no matter what—you must not take any losses.