History
The earliest bicycle and motor-car Carbide lamps were powered by acetylene gas, produced by combining calcium carbide with water. The light given was very bright, although the lamps required regular maintenance; the arrival of battery-powered lamps in the 1890s was well received.
Early battery lamps generally used a lead-acid battery, but these were replaced by self-contained dry cells; lamps became smaller and more reliable. At the same time dynamos were developed which generated energy from the bicycle's own movement. These were more practical, as storage density in batteries was at this time very low.
Not all jurisdictions required use of lights after dark. In the UK the law requiring use of rear lights was resisted by cyclists' groups on the grounds that it downplayed motorists' obligation to be able to stop well within the distance they can see to be clear.
Replaceable-cell battery lights had a renaissance on the invention of the alkaline battery, with a much higher storage density. Moulding techniques for plastics also improved, allowing lens optics to be refined at low cost thus making more efficient use of the light output. During the 1980s the lighting market became more globalised: in Europe, the French "Wonder Lights" and Ever Ready brands gradually disappeared in favour of American, Japanese and German products.
In recent times there have been many advances: exceptionally efficient dynamos; cheap high-output sealed-unit halogen lamps originally developed for decorative lighting; improved storage density in rechargeable batteries driven by the computer industry; high-output light emitting diodes (LEDs); white LEDs; and high intensity discharge (HID) lights crossing over from the automotive sector.
Read more about this topic: Bicycle Lighting
Famous quotes containing the word history:
“[Men say:] “Don’t you know that we are your natural protectors?” But what is a woman afraid of on a lonely road after dark? The bears and wolves are all gone; there is nothing to be afraid of now but our natural protectors.”
—Frances A. Griffin, U.S. suffragist. As quoted in History of Woman Suffrage, vol. 4, ch. 19, by Susan B. Anthony and Ida Husted Harper (1902)
“It takes a great deal of history to produce a little literature.”
—Henry James (1843–1916)
“There is one great fact, characteristic of this our nineteenth century, a fact which no party dares deny. On the one hand, there have started into life industrial and scientific forces which no epoch of former human history had ever suspected. On the other hand, there exist symptoms of decay, far surpassing the horrors recorded of the latter times of the Roman empire. In our days everything seems pregnant with its contrary.”
—Karl Marx (1818–1883)