These letters to Francis Jehl, written in 1923 and 1924, describes Bergmann's work with Edison as a machinist in his Newark workshop on Ward Street during the early 1870s and as a New York City-based manufacturer of Edison phonograph, telephone, and electric lighting equipment from 1876 until 1900. Other Edison associates mentioned include Charles Batchelor, John Kruesi, John F. Ott, and Francis R. Upton, as well the mechanic Sigmund Schuckert.

Courtesy of the Henry Ford Museum and Greenfield Village Research Center.