Contains among other things: Trials of the Telefunkengesellschaft against the company Huth because of patent infringements, 1913 range attempts of the Telefunken-Gesellschaft from Nauen to Togo and Sayville (near New York), Nov. 1913 equipment of ships with radio stations, Dec. 1913 radio station of the Deutsche-Südseegesellschaft für drahtlose Telegraphie in Jap (Karolinen) and Nauru (Marshall Islands) in operation, Dec. 1913 radiotelegraphic length determinations between the stations Eiffelturm and Arlington, Dec. 1913. 1913 Wireless telegraphy in and with the German colonies (newspaper clipping of the "Hamburger Nachrichten"), 1914 patent situation in the field of wireless telegraphy, Jan. 1914 Safety of passenger transport by sea (memorandum of the German government), 1912 - 1914 Opening of the Danish radio station Blaavandshuk, 1914 International treaty for the protection of human life at sea, 1914 Range tests of Nauen with the "Cap Trafalgar" in the Atlantic Ocean, with maps, March - Apr. 1914 Minutes of the meeting of the committee for joint work in the field of radiotelegraphy, 14th Feb. 1914

Contains: Esau, Abraham (Dr.Dr.med. h.c. Dr. phil. born 7.6.1884 in Tiegenhg./Danziggest. 12.5.1955 in DüsseldorfGuest Professor (since 1.3.1949) Shortwave Technology Vapl.Prof. since 1.3.19491949/50 - 1955Study: Physics at the University of Berlin and TH GdanskAfter studying in Gdansk Assistant -1908 with Max Vienna.Doctorate: 1908 in Gdansk (then military time)1912 - 1919 in Togo as head of the receiver laboratory of the company Telefunken1919 - 1925 head of all Telefunken laboratories1925 - 1939 appointment to the University of Jena as head of the institute Technical Physics1935 first as Rector removed by political movement, 1937 however again 1937 on urge of the professors and the student body into his office as Rector appointed; at the same time he became foundation commissioner of the Carl - Zeiss - donation Jena1939 - 1949 he settled as president of the Physikalisch-Technische Reichsanstalt to Berlin over. Since 1949 belonged Professor Esau as a guest professor of the RWTH Aachen, at the same time he was director of the inst. f. For more details see file no. 160a Obituaries.member of the Akademie für Naturforscher und Ärzte in Halle;honorary citizen of the TH Gdansk; honorary senator of the University of Erlangen;honorary doctor of the Med. fac. of the University of Freiburg;member of the aeronautical research of the Forschungsgemeinschaft des Landes NRW.

Contains among other things: Cameroon, considerations and proposals of the company Jantzen and Thormälen. Hamburg, ca. 1892

Drainage of the lagoon 1 km north of Lome. - Request for an expert from the company David Grove GmbH to investigate the water conditions, 1911 [fol. 2] Re-erection of the beacon on the bridgehead, 15 September 1912 [fol. 6] Road construction at the Schweinfurth waterfall at Misa-Höhe. - Recourse claims against Baurat Meier, Buea, due to omissions in the construction of a culvert for the waterfall, 1912 [fol. 9 - 20]

Explanation: The company was run under this name as its own business since 1888 by Johann Karl Vietor, but was able to make use of the branches in Ghana, Togo, Dahomey, Cameroon, Liberia and Guinea, which had been founded by other members of the Vietor family since 1857. After the severe setback in the First World War, the company was rebuilt in Liberia, Ghana and Togo, but this was destroyed by the world economic crisis, so that the company died out in 1932. It was partly in close contact with other companies co-founded by J. K. Vietor. Content: Business papers before the First World War, in particular land purchases, inventories, insurance of factories in Togo (Anedlo, Palime, Lomé), in Ghana (Keta) and in Dahomey (Porto Novo) - Complete company registration after the First World War, in particular Reich compensation for war and colonial damage, correspondence with other companies and own branches - Liquidation

'Erkundungsmarsch in das Gebiet des Benue vom 21.10.1902 -7.1.1903. - Bericht von Oberleutnant Dominik