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1916 and the fall of 1917, added to the difficulty of arranging for the permanent
care of the boys, but once her health improved in early 1918, Mileva made it clear
that she would not agree to Einstein’s proposal that Hans Albert be taken out of her
care (Docs. 8, 461a, 475a, 482a, and 482b).
Einstein canceled an intended visit to Zurich and a walking tour with the chil-
dren in the Alps in the summer of 1918. In his first letter to be published in this se-
ries, from June 1918, which accompanied a letter from Hans Albert, the almost
eight-year-old Eduard expressed his disappointment that Einstein canceled his
planned vacation with them. In subsequent correspondence, he reported on his
readings, hobbies, and playmates, and his regret at having to miss a performance in
a school play because of poor health (Docs. 8, 557c and 659c, and Doc. 9, 183a).
Within a period of four months, Eduard had been afflicted twice with Spanish in-
fluenza (Docs. 8, 557a, 588a, and 646a). Hans Albert, too, wrote of his disappoint-
ment, and one month later explained that it was impossible for him to visit Einstein
in Germany, as he was indispensable in the daily care of the family (Docs. 8, 557b
and 588b).
By the end of June 1918, Einstein, Elsa, and her daughters left for a two-month
stay at the seaside resort of Ahrenshoop on the Baltic Sea. During that period,
Einstein discussed with Swiss colleagues a joint appointment with Zurich. Al-
though Einstein declined, he accepted the invitation to give guest lectures of 5–6
weeks each, twice a year. During that summer, the administrative steps leading to
a final divorce from Mileva took place in Zurich. An agreement was signed in June.
At the end of August, Einstein sent a formal letter, admitting to an adulterous rela-
tionship, to their mutual friend Emil Zürcher Jr., who acted as Mileva’s attorney.
After the end of World War I, in late December 1918, Einstein gave a deposition in
Berlin for the Zurich divorce court, and then traveled in early 1919 to Switzerland,
where he delivered the first series of guest lectures and finalized his divorce on 14
February.
Four weeks after his marriage to Elsa Einstein on 2 June 1919, only a few days
after the solar eclipse whose observation would confirm his general theory of rela-
tivity, Einstein embarked on a seven-week trip away from Berlin. He traveled to
Switzerland to be with his terminally ill mother, spend time with his sons, and lec-
ture on relativity in Zurich. In a series of twenty-three postcards to Elsa, Einstein
recounts his weekly commute between Zurich and the sanatorium in Lucerne
where Pauline Einstein was hospitalized, and his distress at “the thoughts of my
mother’s torments.” But he derived “indescribable joy” from the company of Hans
Albert, with whom he was engaged in the construction of an airplane model. Elsa,
however, was displeased that Einstein had chosen to stay temporarily in “the