C A L E N D A R O F A B S T R A C T S 1 9 2 4 8 6 9 337. From Otto Halpern Vienna, 4 April 1924 Replies to Doc. 216. Cannot agree with AE’s point (2c) because in classical theory the friction force increases with increasing temperature T, whereas in quantum theory this force remains finite if one takes the coefficients A independent of T. This is in conflict with the correspondence principle. The only way out is a temperature dependence of the A’s and B’s. Also disagrees with AE’s point (2a) on the basis of experimental data, which seem to indicate a temperature dependence of the absorptive power of atoms. ALS. [12 123]. 338. From Leo Kohn London, 7 April 1924 Thanks for AE’s assistance in regard to the Günzburg library. Sends another letter to sign and return (Doc. 232). Updates on the progress of construction on Mount Scopus. Ignaz Goldziher’s library has also been acquired. TLS. [36 873]. 339. From the Office of Max Warburg Hamburg, 8 April 1924 Has received Abs. 341. Will give the letter to Max Warburg after his return at the end of the week. TLS. [36 874]. 340. To the International Education Board [Berlin, before 9 April 1924] Acknowledges the receipt of a check in the amount of $250 (1,047 M) from Heinrich Poll. TDS. [80 983]. 341. To Max Warburg [Berlin, before 9 April 1924] Expresses support for a project to establish a Jewish university in Poland for the young people of Eastern Europe asks Warburg to serve on the international committee, which is being set up to oversee the project, as one of its six members from Germany and the U.S. He was visited the previous day by the industrialist Henryk Doktorowicz from War- saw, the prime mover behind the project. PTrL, fragment and abstract (Sotheby Auction Catalog, 21 May 1987, lot 236). [72 170]. 342. From Roberto Marcolongo [Naples,] 10 April 1924 Thanks for AE’s kind reply and warm comments on Marcolongo 1923. They impatiently await his lecture, set for 7 May. Inquires whether AE will speak in Italian, as in Bologna, and requests his arrival date and the title of his lecture. ALS. [44 515]. 343. From Hugh J. Gramatzki Berlin, 13 April 1924 When two condensed systems in a medium propagate with the same velocity in the same direction, there must be gravitational attraction between them that after a while brings these two waves in phase. Can the coherence of a light beam of several meters in diam- eter be explained by the gravitation between the masses in it, equivalent to the energy of radiation? A terrestrial experiment is proposed with light beams of 2–5 m cross section. Asks how light behaves when entering a double refracting medium. It must follow the path of only one of the refracted components. ALS. [11 386]. 344. From Max Warburg Hamburg, 17 April 1924 Upon his return responds to Abs. 341. Asks not to include him and his brother, Felix Warburg, on the committee. TLS. [36 875]. 345. From Rabbi Kaelter Danzig, 21 April 1924 Asks AE to lend his name in support of the Jewish university in Danzig to thwart the adverse consequences of the premature reports by the Jewish Telegraph Agency on the discussions of its foundation initiated by Henryk Doktorowicz with the ICIC of the League of Nations. As the representative of Danzig Jewry, requests AE to accept the