It was in Stettin on 24 June 1905 when Dr. Hermann Fottinger was granted Patent No. 2214 22 of the German Reich for a "hydrodynamic transmission with one or several driving and one or several driven turbine wlieels for power transmission between adjacent stiafts". Originally intended for marine drives, this hydrodynamic power transmission principle was at first celebrated as an "epoch-making" invention, only to be driven out of its field of application within a few years by mechanical units with improved gear technology. The German shipbuilding industry subsequently put the Fottinger principle "ad acta". A quarter of a century went past, before the "Maschinenbauanstalt Johann Matthaus Voith" in Heidenheim, south Germany, signed a licensing agreement with the inventor on 17 April 1929, enabling Voith to utilize his idea. What were the reasons behind this? Peter Edelmann, Member of the Board of Voith AG and Chairman of the As early as 1906, Voith engineers from the turbine department had support­ Board of Voith Turbo. ed Fottinger with their experiences. Through this contact, they became acquaint­ ed with the function and the possibilities of the Fottinger principle. Twenty years later, when Voith received an order for the pumps and the turbines of the "Herdecke" pumped storage plant, Voith resorted to the specific advantages of a hydrodynamic coupling to enable the transmission of 36 000 HP.