The following is a list of people who worked for Thomas Edison.Edward Goodrich Acheson – chemist, worked at Menlo Park 1880–1884 William Symes Andrews – started at the Menlo Park machine shop 1879 Charles Batchelor – "chief experimental assistant" John I. Beggs – manager of Edison Illuminating Company in New York, 1886 William Kennedy Dickson – joined Menlo Park in 1883, worked on the motion picture camera Justus B. Entz – joined Edison Machine Works in 1887 Reginald Fessenden – worked at the Edison Machine Works in 1886 Henry Ford – engineer Edison Illuminating Company Detroit, Michigan, 1891–1899 William Joseph Hammer – started as laboratory assistant Menlo Park in 1879 Miller Reese Hutchison – inventor of hearing aid Edward Hibberd Johnson – started in 1909, chief engineer at West Orange laboratory 1912–1918 Samuel Insull – started in 1881, rose to become VP of General Electric (1892) then President of Chicago Edison Kunihiko Iwadare – joined Edison Machine Works in 1887 Francis Jehl – laboratory assistant Menlo Park 1879–1882 Arthur E. Kennelly – engineer, experimentalist at West Orange laboratory 1887–1894 John Kruesi – started 1872, was head machinist, at Newark, Menlo Park, Edison Machine Works Lewis Howard Latimer – hired 1884 as a draftsman, continued working for General Electric John W. Lieb – worked at the Edison Machine Works in 1881 Thomas Commerford Martin – electrical engineer, worked at Menlo Park 1877–1879 George F. Morrison – started at Edison Lamp Works 1882 Edwin Stanton Porter – joined the Edison Manufacturing Company 1899 Frank J. Sprague – joined Menlo Park 1883, became known as the "Father of Electric Traction". Nikola Tesla – electrical engineer and inventor, worked at the Edison Machine Works in 1884 Francis Robbins Upton – mathematician/physicist, joined Menlo Park 1878 Theo Wangemann – personal assistant to Edison John Birkinbine - mining technician that developed re-refining technique in 1889 Alfred O'Tate Norman Raff Frank Gammon Andrew and Edwin Holland, brothers