D O C U M E N T 1 7 3 J A N U A R Y 1 9 2 6 1 9 1 What does the final clause mean: “New calculations seem to yield that these equations (the gravitational equations) deliver the motions of electrons”? In what sense of “yield”? Why is was this doubtful? Why is it doubtful “whether quanta find a place in there”? Should the first sentence be understood in the sense that an electron at rest (and therefore also a moving one) can be built up, perhaps excluding its absolute value, “but” quanta cannot? According to dimensional considerations, isn’t an electron’s absolute value (and only this value) related to the action quantum? I haven’t caught sight of the Heisenberg-Born-Jordan theory yet. Where did it appear? A young chemist who recently took his doctorate showed me amazing con- nections between material constants of compounds and components, from which it appears that very much, relatively speaking, can be gathered about polymerization conditions. The formulas used are quite incomprehensible to me ¢that is² I can only partly see how the assumptions can be expressed in words. May I send you the short paper, even though it is still quite informal? Does your academy also have a sealed depository, by chance, as in Paris, to safeguard a priority claim? If so, maybe after you have read it sometime, it could be deposited there for the time being while other material is being compiled. When you come here, you must see this young man there is something of the inventive ponderer about him. Must you instill peace in Zion? That is a saint’s calling, isn’t it? — And that see you next year in Jerusalem was just the usual pious wish! Warm wishes to you and yours! Michele 172. From Judah L. Magnes Jerusalem, 20 January 1926 [See documentary edition for English text.] 173. To Paul Painlevé [Berlin,] 21 [January 1926] Dear, esteemed Mr. Painlevé, Forgive me for writing in German, I do so ¢for the sake of clarity² in order to be able to express myself clearly.