D O C U M E N T S 1 6 2 , 1 6 3 N O V E M B E R 1 9 2 3 2 5 9 162. From Robert A. Millikan[1] [Pasadena,] November 27, 1923 Dear Dr. Einstein: It was certainly very thoughtful of you and Drs. Lorentz, Kamerligh Onnes, and Ehrenfest to take the trouble to send me your congratulations by cable half way around the earth upon the Nobel award.[2] I suspect that I owe this award in no small degree to some kind words which you may have been guilty of saying in my behalf to the committee. In any case, I wish you to know that there are no congrat- ulations which I appreciate more than those which come from the man who has contributed in such an extraordinary way to practically all of the developments of modern physics. My little contributions have consisted mainly in adducing new ex- perimental evidence for the correctness of his ideas. With kindest regards to both Mrs. Einstein and yourself, I am Very cordially yours, R. A. Millikan TLS. [17 290]. Written on letterhead “California Institute of Technology, Pasadena, Norman Bridge Laboratory of Physics” and addressed “Professor Albert Einstein, University of Berlin, Berlin, Ger- many.” [1]Millikan (1868–1953) was chairman of the executive council of the California Institute of Tech- nology (Caltech). [2]The Nobel Prize in Physics for 1923 was awarded to Millikan “for his work on the elementary charge of electricity and the photoelectric effect” (see Nobelstiftelsen 1989, p. 58). 163. From Théophile de Donder[1] 5 Rue de l’Aurore, Bruxelles, 30-11-1923. Monsieur et très honoré Collègue, Je me suis vivement intéressé à vos nouvelles recherches tendant à faire dispa- raitre l’introduction a priori de la densité électrique, et à ramener toute l’étude du champ gravifique accompagnant le champ électromagnétique pur, aux dix fonc- tions et aux six fonctions . Il me serait agréable d’obtenir quelques éclaircissements sur le point suivant vous obtenez[2] or, dans les ancien exposés,[3] on avait gαβ fμν –fμν 1§ β© -- - ∂xν ∂iμ ∂xμ¹ ∂iν – ¨ ¸ · =