Vintage 1950s green enamel light shade original not reproduction probably by Benjamin lights 32 cm round 
Benjamin lights
Some age related wear
1805 Philips and Lee's Cotton Mill, Manchester was the first industrial factory to be fully lit by gas. 1809 Humphry Davy publicly demonstrates first electric lamp over 10,000 lumens, at the Royal Society. 1813 National Heat and Light Company formed by Frederick Albert Winsor.
The history of Benjamin lights is marked by the company's founder, Reuben Berkley Benjamin, who was a prolific inventor in the field of electric lighting:
Founding
In 1898, Benjamin founded the Benjamin Electric Manufacturing Company in Chicago, Illinois.
Patents
The company filed its first patent for an electric lamp socket in 1898.
Expansion
The company grew rapidly in popularity and expanded throughout the United States and Canada, and eventually to England.
R.L.M. enamel shade
Benjamin's R.L.M. enamel shade was a highly influential design that is now considered the classic industrial enamel.
Non-contact fire alarm horns
The company introduced a series of non-contact fire alarm horns in the early 1920s.
Industrial lighting
Benjamin Electric Ltd. described itself as a "pioneer of scientific industrial lighting".
Equipment for ships and aircraft
Benjamin equipment was used in the cockpits, landing lights, and identification and signaling lamps of most types of fighters and bombers