sentences:  He taught in the town of Düsseldorf, where he also founded his own boys' school in 1850.In between 1852 and 1854 Wilhelm became the private teacher of Stephanie of Hohenzollern (the daughter of Prince Karl Anton of Hohenzollern-Sigmaringen), the future queen of Portugal; he also taught the kids of Robert and Clara Schumann, while their parents were touring in Europe.From 1868 onwards, Wilhelm Herchenbach focused on writing, and by the time of his death in 1889, his works comprised over 300 books.