EINSTEIN, ALBERT. Four autograph letters signed ("Papa") to Hans Albert Einstein, Berlin and n.p. [probably Berlin], 25 January 1915 - 23 December 1915 and n.d. Together 11 pages, 4to and 8vo, one letter with portion of lower blank margin excised.
"I HAVE JUST COMPLETED THE MOST SPLENDID WORK OF MY LIFE"
A fine series of letters, to the eleven-year-old son who later became a scientist, spanning a momentous year in which Einstein accomplished some of his most important scientific acheivements, including the completion of the General Theory of Relativity. 25 January 1915: Einstein has heard from Hans Wohlwend and an aunt in Lucern that Hans Albert and Eduard are both well and that they had a nice excursion to the Zurichberg. He hopes that Hans Albert has found his old friends [in Zurich, on his return from Berlin] and remarks that "There is no place that is so pleasant and healthy for children as Zurich. There, boys are not overloaded with chores and are not burdened with obligations...Don't forget to practice the piano! Making beautiful music can be a joy to oneself and to others. For example, this evening I am playing in a little concert which will benefit two poor artists. In the last weeks Mr. de Haas and carried out a wonderful and important experiment with magnets. Sometime when we are together again I will tell you about it." He has been giving math lessons to Fritz Haber's son, who has been too ill to go to school. He has no news about Hans Albert's old friends in Berlin. "I have a very tiny apartment where I am accustomed to work all day long. Sometimes I even cook my own lunch." Undated: Einstein has received two of Hans Albert's letters, which please him, and he asks if Hans Albert wrote them by himself. He excuses himself from an Easter visit, but promises to come in the summer. "I will tell you many pretty and interesting things about science and other subjects. I am glad you like geometry. It was my favorite subject when I was a little older than you, perhaps about twelve, but I had no one to show me anything, so I had to learn it from books. I would take great pleasure in instructing you, but that isn't possible. If you would write me occasionally what you have learned, then I would give you a nice problem to solve." He cautions Hans Albert Albert to brush his teeth every day and go to the dentist whenever necessary. "I do this, and I am glad to say that I have kept my teeth well enough. This is very important. You yourself will see this later." He is sending Hans Albert and Eduard toys for Easter and urges Hans Albert not to neglect the piano: "You won't believe how much pleasure one can give himself and others by playing well." 4 November [1915?]: Einstein was glad to get Hans Albert's letter, because he had thought that perhaps he hadn't wished to write him anymore. When he was in Zurich, Hans Albert had said that it was not comfortable to have him there, so he proposes they meet somewhere else. He will insist that they have a month together every year, so that Albert will see that he has a father who is attached to him and loves him. "You can also learn many good and beautiful things from me, which you would not get so easily from anyone else. What I have accomplished through strenuous work should not be only for strangers, but especially for my own sons. I have just completed the most splendid work of my life..." [probably his calculation of the precession of the perihelion of Mercury, which proved the General Theory of Relativity]. He is glad that Hans Albert likes the piano and adds that "music and carpentry were my favorite occupations when I was your age, even more than schoolwork." 23 December 1915: Einstein will not be able to visit this Christmas because he needs to rest after the hard work of recent months [by 25 November 1915, he had completed the outline of the logical structure of the Theory of General Relativity], and because crossing the border will be difficult. As Hans Albert requested, he has sent his Christmas present in the form of money. He asks for a photograph of Hans Albert and Eduard and inquires about Hans Albert's schoolwork. Chlorcalcium (for which he gives the chemical formula), is important, he has heard, for the development of teeth and bones, and he describes how and when it should be taken by both boys. (4)