Through his relationship with Freundlich, Mendelsohn had the opportunity to design and build the "Einsteinturm" ("Einstein Tower"). This relationship and also the family friendship with the Luckenwalde hat manufacturers Salomon and Gustav Herrmann helped Mendelsohn to an early success. From then until 1918, what is known of Mendelsohn is, above all, a multiplicity of sketches of factories and other large buildings, often in small format or in letters from the front to his wife, Louise Mendelsohn (née Maas; 1895–1980). The 2011 documentary film by Duki Dror titled "Incessant Visions" is about Erich Mendelsohn and his wife, in which Dror animates the memoirs of Louise and the letters.