A percussion instrument consisting of a steel rod bent into the form of a triangle, with one angle left open (for illustration, See Percussion instruments). It is normally suspended and struck with a steel beater (or a drumstick), producing a high, silvery sound of indeterminate pitch. Dating from ancient times, it was used in the Middle Ages and Renaissance for religious purposes as well as in secular music. It was used in the orchestra by the end of the 18th century (Mozart, Haydn and Beethoven all wrote for it), in military and janissary-related music, but in the 19th century its varied uses included the tremolo (e.g. Wagner's Die Meistersinger) and even the solo (Liszt's E♭ Piano Concerto).