hair stretched with use. He also designed a round-edged frog mounted to the butt by means of a recessed track, which he encouraged his bowmakers to use; other details of craft, however, make it possible to identify the actual maker of many Vuillaume bows. The bows are stamped, often rather faintly, either "vuillaume à paris" or "j.b. vuillaume". Other innovations include the insertion of Stanhopes in the eye of the frogs of his bows, a kind of mute (the ) and several machines, including one for manufacturing gut strings of perfectly equal thickness. Many of the great bow makers of the 19th century collaborated with his workshop. Jean Pierre Marie Persois, Jean Adam, Dominique Peccatte, Nicolas Rémy Maire, François Peccatte, Nicolas Maline, Joseph Henry, Pierre Simon, François Nicolas Voirin, Charles Peccatte, Charles Claude Husson, Joseph Fonclause, Jean Joseph Martin, and Prosper Colas are among the most celebrated. Vuillaume was an innovative violin maker and restorer, and a tradesman who traveled all of Europe in search of instruments. Due to this fact, most instruments by the great Italian violin makers passed through his workshop. Vuillaume then made accurate measurements of their dimensions and made copies of them. He drew his inspiration from two violin makers and their instruments: Antonio Stradivari and his "Le Messie" (Messiah), and Giuseppe Guarneri del Gesù and his "Il Cannone" which belonged to Niccolò Paganini; others such as Maggini, Da Salò and Nicola Amati were also imitated, but to a lesser extent. Vuillaume made numerous copies of his favorite violin "Le Messie", the more noteworthy among them being: Vuillaume was able to craft such a perfect replica of "Il Cannone", that upon viewing them side by side, Paganini was unable to tell which was the original. He was able to recognize the master instrument only upon hearing subtle differences in tone during playing. The copy violin was eventually passed on to Paganini's only student, Camillo Sivori. Sivori owned great violins by Nicolò Amati, Stradivari, and Bergonzi, but the Vuillaume was his favourite. This violin is owned by the Musei Di Genova and displayed in their Palazzo Tursi. When making these copies, Vuillaume always remained faithful to the essential qualities of the instruments he imitated – their thickness, the choice of the woods, and the shape of the arching. The only differences, always the result of a personal decision, were the colour of the varnish, the height of