D O C . 3 3 9 M A R C H 1 9 2 0 2 8 5 very familiar to me.[4] Unfortunately I have not been able to keep track of your work since the Outline of a Generalized Theory of Relativity and of a Theory of Gravitation (1913).[5] The war drew me in an entirely different direction. With ev- ery effort, I managed to keep the institute and lecturing running. In 1917/18 I was needlessly dean, 1918/19 vice-dean, member of the senate and, as such, heavily burdened with university politics. In the university’s heroic battle for its very exist- ence, science was necessarily pushed into the background for me. Then came the collapse.[6] Today it seems almost a miracle to me that I could withstand this period with its terrible demands without losing my mental equanimity. Since receipt of your letter I had another severe blow to endure, having lost my father.[7] And thus I beg your pardon for acknowledging only today your letter and shipments. The Ehrenhaft affair is now nearing its resolution. From time to time I hear iso- lated details about the current state. But it is surely of little use if I pass on to you my fragmentary information. If E. should ultimately prevail, which I do not con- sider impossible, he will have your recommendation to thank for it in more than a small degree.[8] I am forwarding to you at the same time two short essays, one on Mach, another on scientific tales.[9] I would be pleased if they caught your interest. With cordial greetings, yours, A. Lampa. 339. From [----] Blau[1] Berlin O. 17, 11–14 Ehrenberg St., 5 March 1920 Esteemed Professor, The A.E.G., as owner of German Reich Patent 269498 (the so-called [wire-] drawing patent),[2] has been pursuing a number of patent infringement cases for years. The situation is very much complicated by the fact that a large number of com- panies with limited liability are involved thus are very hard to pin down because one of them always sells what the other or a third party had manufactured. We have nevertheless managed to pin down one company, Sannig & Co. Ltd.[3] Even though the Reich court has already decided on the validity of the patent, Sannig & Co. has recently filed a nullity suit, which was rejected by the Patent Of- fice and has now likewise reached the Reich court. As you will know, the patent in question is one of the foundations upon which the consortium between the incandescent-lamp factories of the Auer Company in liquidation, Siemens & Halske, A.E.G, and the new limited partnership Osram Co., Ltd., is based. Privy Councillor Koppel is one of the main interested parties of this concern.[4]