Wind instr. octave deeper than bassoon and notated octave higher than it sounds, though Wagner and Debussy sometimes wrote for it at pitch. Some baroque examples were made but standard modern design is Heckel's (1876). Conical bore tube is 18' long, with 5 parallel sections connected by 4 U‐bends. Crook fits into metal tube. Brahms scored for it in his 1st Sym. In Strauss's Salome there is a long solo for the instr. when Jokanaan descends into his cell.