8 8 6 C A L E N D A R O F A B S T R A C T S F E B R U A R Y 1 9 2 9 891. From Hans Hönlinger Müglitz, 10 February 1929 Requests help in convincing conservative foresters to accept his theory, according to which the most profitable clearing of forests is not after sixty but after one hundred years. ALS. [46 719]. 892. From Max Wertheimer Frankfurt a. M., 10 February 1929 On financial problems with I. Benrubi’s invitation to deliver lectures in Berlin (see Abs. 608). ALS. [23 380]. 893. From Raschko Zaycoff Sofia, 10 February 1929 Gives plan of further research. Intends to generalize AE’s new theory, to find new spe- cial cases and a connection between AE’s and Dirac-Whittaker’s theories. ALS. [24 214]. 894. From Annie Oswald Garmisch, 11 February 1929 Her mother, an acquaintance of AE’s parents, remembers the five-year-old AE. Invites AE for a visit, together with family. ALS. [30 373]. 895. From Melania Serbu Braşov, 11 February 1929 Happy with receiving the book promised in Abs. 819. Following AE’s advice, she will keep track of her progress in understanding a world that was so unfamiliar to her not long ago. Will express her thanks by making AE proud of his “little sister.” ALS. [39 106]. 896. From Giuseppe Vitali Padova, 11 February 1929 Requests a copy of Einstein 1929n (Doc. 365) after having been informed by Tullio Levi-Civita about it and having heard about it in political newspapers. Mentions his own works (Vitali 1925 and probably Vitali 1924, both in Einstein’s offprint collection), as well as a paper by Weitzenböck from 1923, and a recent paper of Enea Bortolotti on the same topic (Bortolotti, Enea 1927). TLS. [23 181]. 897. To Ernst Klug [Berlin,] 13 February 1929 Comments on the nature of the gravitational field generated by moving coordinate sys- tems. All bodies in such a frame have to have the same velocity vector. TLSX. [25 126]. 898. To George M. Nelson Berlin, 15 February 1929 Post office sends return receipt. PDS. [78 776]. 899. To Helene Nostitz-Hindenburg Berlin, 16 February 1929 Following her request, AE is willing to join the select committee of the Deutscher Kulturbund. PALf. [123 461]. 900. To Hans Stürmer [Berlin,] 16 February 1929 In response to Abs. 889, congratulates the author on his book Stürmer 1929 and its ped- agogical excellence in explaining the concepts of psychoanalysis. Will forward the book to Eduard Einstein. Appreciates Stürmer’s independence from scientific and social tra- dition. TLC. [48 540]. 901. From Richard Heilner Bietigheim, 16 February 1929 Attaches his lecture on the German economy and a European union. The abolition of customs would result in an upturn in the economy. Asks for opinion. TLS. [46 608].