Answer
Hindemith wrote "Der Schwanendreher" for the viola, which is a string instrument in the violin family. The viola is smaller than the violin but larger than the cello. It has a rich, mellow sound that is often used in classical music. "Der Schwanendreher" is a piece of music that is often played by viola players. It is a beautiful piece of music that is both challenging and rewarding to play.