C A L E N D A R O F A B S T R A C T S 1 9 2 6 9 2 7 503. From Georg Bayer Fürth, 17 June 1926 Would like to correspond with AE. Has in his possession Einstein 1917a, and believes he has made a discovery regarding the puzzle of the rotation of a cube inside a cube. ALS. [43 216]. 504. To Georges Oprescu [Berlin,] 18 June 1926 Has transmitted Oprescu’s communication to Arthur Korn (see Abs. 499), who thanks him and agrees with the proposed path of action (see Abs. 501). As of 12 July, he can be reached at Mileva’s address, Huttenstr. 62 in Zurich. TTrL. [82 813]. 505. To Chaim Weizmann [Berlin,] 18 June 1926 Recommends Israel (Arthur J.) Kraus, who despite great difficulties of a political nature, has obtained his Ph.D. in Germany and requests an introduction to English academia. ALSX. [37 741]. 506. From Hendrik A. Lorentz Haarlem, 18 June 1926 Following up on Ehrenfest’s letter (Doc. 302), he too is inviting AE to Leyden for a few days this month. Oskar Klein, who has developed interesting considerations with regard to Schrödinger’s theory and is working with Bohr, is now in Leyden as well for the month, supported by the Lorentz Fund. Klein makes a very good impression he is very modest. ALSX. [16 605]. 507. From Georges Oprescu Geneva, 18 June 1926 In its session of 9 June 1926, the council of the League of Nations approved the report of the French representative containing the following resolutions: the nomination of J. Casares to replace Torres Quevedo as member of the commission on the office terms of members H. A. Lorentz’s letter of 26 March 1926 to the council. TLS. [84 634]. 508. From Erich Bobsin Berlin, 19 June 1926 Because of Prof. Max Jakob’s trip, he is only now able to send the enclosed certificate. ALS. [43 303]. 509. From Hermann Friedmann Berlin, 19 June 1926 He is unable to prove that the definition of time is incompatible with spe- cial relativity. Requests a recapitulation of the train of thought. Will be in Helsingfors. ALS. [11 125]. 510. From Max Hirsch Berlin, 20 June 1926 Proposes that the electron is not homogeneous, but that it is constituted of a point of mass that moves on the outside of the electron on an elliptical path with an inner positive electron rotating in the opposite direction. The electric field would thus be nothing but a centrifugal field, and the magnetic field would be a remaining state of the field. This could be investigated with general relativity. ALS. [43 903]. 511. From Hayari Miyake Fukuoka, 20 June 1926 After a sixteen-day trip, returned to Japan on 6 June and thanks AE for the warm wel- come in Berlin. The trip through dark Russia was exhausting. Some young English trav- elers who took photographs of the trip through Siberia were arrested, as had happened to two Japanese in the past. One is not allowed to take photographs. ALS. [44 460]. 512. From Georges Oprescu Geneva, 21 June 1926 Will prepare AE’s letter and Korn’s proposal for submission to the ICIC meeting (see Abs. 504). TLS. [44 188]. tB tAt′A =