2 2 8 D O C U M E N T 2 1 8 M A R C H 1 9 2 6 Your note in Nature has interested me very much. For it yields a mathematical interpretation of the tensor , whose introduction into the general theory of rel. is suggested by the cosmological problem. I have developed this in a paper that will appear in the Riemann Festschrift.[4] Kind regards, your A. Einstein 217. Discussion at the Meeting of the Kuratorium of the Physikalisch-Technische Reichsanstalt [Berlin,] Meeting on 11 March 1926 [Not selected for translation.] 218. To Hendrik A. Lorentz [Berlin,] 13 March 1926 Dear Mr. Lorentz, Unfortunately I am not going to be able to be present either at the directors com- mittee meeting on March 25th[1] or at the committee meeting on the meteorology business on the 29th [2] that is, I could only come to Paris in a case of great urgency. I do not know whether it is permissible for me to let myself be represented at both these meetings by our colleague Langevin,[3] who would surely be ready to assume this representation on the 25th and, in all probability, also on the 29th. I have al- ready written to Mr. Painlevé[4] about the meeting on the 25th. Please kindly in- form me about whether a representation by Langevin on the 29th would be possible. The meteorologists from Paris and Brussels were so kind as to write to me about the meeting on the 29th, and I am quite unhappy not to be able to thank them by letter because—their signatures are indecipherable. Your kind notice about the grim loss we have suffered by the death of Kamerlingh-Onnes[5] has deeply affected me. It is wonderful when a person can devote his entire life to performing one great task and can complete this task so per- fectly. What is even more wonderful, though, is the harmonious spirit and intimate sense of community that unites scholars over there in Holland. That is something unique in the world. Rik 1 4 -- - gikR –