300 THE LATER JOURNEY
Germany and added, 'Without this help it would hardly be possible for me to stay
here; nor do I know if things can continue the way they are' [E3]. As a Swiss
citizen, he was entitled to and did receive food parcels from Switzerland [E4], but
that was evidently not enough to compensate for the food shortages in Berlin
caused by the war. He did not follow the advice of his doctor, who had urged him
to recuperate in Switzerland [E5].
At that stage Elsa Einstein Lowenthal took matters in hand. Elsa, born in 1876
in Hechingen in Hohenzollern, was both a first and a second cousin of Albert's.
Rudolf, her father, was a first cousin of Hermann, Albert's father. Fanny, her
mother, was a sister of Pauline, Albert's mother. Elsa and Albert had known each
other since childhood, when Elsa would visit the relatives in Munich and Albert
would come to Hechingen. They had grown fond of each other. In her early twen-
ties, Elsa married a merchant named Lowenthal, by whom she had two daughters,
Use (b. 1897) and Margot (b. 1899). This brief marriage ended in divorce. When
Einstein arrived in Berlin, Elsa and her daughters were living in an upper-floor
apartment on Haberlandstrasse No. 5. Her parents lived on lower floors in the
same building. Elsa's presence in Berlin had been one of the factors drawing Ein-
stein to that city.
It was principally Elsa who took care of her cousin during his illness. In the
summer of 1917, Einstein moved from the Wittelsbacherstrasse to an apartment
next to Elsa's. In September he invited Besso to visit him in his spacious and
comfortable new quarters [E6]. In December, he wrote to Zangger that he felt
much better. 'I have gained four pounds since last summer, thanks to Elsa's good
care. She herself cooks everything for me, since this has turned out to be necessary'
[E7]. However, he still had to maintain a strict diet and was never sure that severe
pains might not return [E8].
Toward the end of the year, his health worsened. It turned out that he was
suffering from a stomach ulcer [E9, E10]. For the next several months, he had to
stay in bed [E10]. His feelings were at a low ebb: 'The spirit turns lame, the
strength diminishes' [Ell]. While bedridden, he derived the quadrupole formula
for gravitational radiation. In April 1918 he was permitted to go out, but still had
to be careful. 'Recently I had a nasty attack, which was obviously caused only
because I played the violin for an hour' [E10]. In May he was in bed again, this
time with jaundice [El2], but completed a fundamental paper on the pseudotensor
of energy-momentum. His dream (in August [E13]) that he had cut his throat
with a shaving knife may or may not have been a reaction to his state of health.
In November he published an article on the twin paradox. In December he wrote
to Ehrenfest that he would never quite regain his full health [El4].
By that time, Albert and Elsa had decided to get married, and therefore Einstein
had to institute procedures to obtain a divorce from Mileva [E15]. The divorce
decree was issued on February 14, 1919. It stipulated that Mileva would receive,
in due course, Einstein's Nobel prize money.*
*See further Chapter 30.