Complex sentence: In 1892, Rathgen passed his habilitation at the Friderich Wilhelms University of Berlin and the following years was appointed extra-ordinary, in 1895 ordinary Professor of the University of Marburg and from 1900 to 1903 was temporarily in charge of Max Webers Chair at University of Heidelberg.
Split into simpler sentences: In 1892, Rathgen passed his habilitation at the Friedrich Wilhelms University of Berlin and the following years was appointed extra-ordinary, in 1895 ordinary Professor of the University of Marburg. From 1900 to 1903, he was temporarily in charge of Max Webers Chair at University of Heidelberg.