High Quality Content by WIKIPEDIA articles! Adelbert Theodor Edward Wangemann (February 13, 1855 – June 1906), known as Theo, was a German who emigrated to the United States. In 1888, he began working for Thomas Edison as an assistant at his laboratory in West Orange, New Jersey. In 1889, Edison sent Wangemann to keep the phonograph at the 1889 Paris Expo in good working condition. The trip was extended and Wangemann made numerous early sound recordings on wax cylinders, some of which were lost for more than 100 years. Found in 1957, but not revealed until 2012, they include the only known recording of Otto von Bismarck.