David Misell (or Meisel)

David Misell invented the modern hand-held flashlight as well as a wooden-cased signal light, an electric bicycle light, and a head-mounted electric light. He and a Russian immigrant to the United States named Akiba Horowitz formed the American Electrical Novelty & Manufacturing Company which later became the battery company, "The American Ever Ready Company". David and Akiba marketed their first flashlights to police officers in New York. Positive reviews of the flashlight lead to a profitable business, but unfortunately David does not appear to have shared in the rewards.

The flashlight was so named because its original design was so temperamental that the light flashed and flickered on and off. It was not until 1916 that the technology was fully vetted and Eveready could advertise that their flashlight was "the light that does not flicker in a draught, extinguish in the wind, and is controlled instantly by finger pressure. It's the light everyone needs."

See also: http://www.ideafinder.com/history/inventions/flashlight.htm