Electric light be made with a screw-thread base, two metal pins, two metal caps or a bayonet cap. The three main categories of electric lights are incandescent lamps, which produce light by a filament heated white-hot by electric current, gas-discharge lamps, which produce light by means of an electric arc through a gas, and LED lamps, which produce light by a flow of electrons across a band gap in a semiconductor. Before electric lighting became common in the early 20th century, people used candles, gas lights, oil lamps, and fires. Cornish chemist Humphry Davy developed the first incandescent light in 1802, followed
Sydney Electric Train Society Sydney Electric Train Society The Sydney Electric Train Society is a railway preservation society in Sydney, Australia. It specialises in NSW electric traction and particulary NSW electric locomotives. The Sydney Electric Train Society (SETS) was established in 1991. In January 1992, it operated its first tour with single deck stock across the CityRail suburban network, the last of which were about to be withdrawn. On 20th April 1998 SETS purchased 46 class electric locomotive 4615. Later in 1998, it purchased four Tulloch power cars from the State Rail Authority along with some U set stock. It has since expanded its