Octobass
The octobass is an extremely large and rare bowed string instrument, a larger three-stringed version of the double bass, first built around 1850 in Paris by the French luthier Jean-Baptiste Vuillaume (1798–1875). The specimen in the collection of the Musée de la Musique in Paris measures 3.48 metres (11 ft 5 in) in length, whereas a full-size double bass is generally approximately 2 m (6 ft 7 in) in length.