History
In 1896, the first dry cell battery was invented. Unlike previous batteries, it used a paste electrolyte instead of a liquid. This was the first battery suitable for portable electrical devices, as it did not spill or break easily and worked in any orientation.
On January 10, 1899, American Electrical Novelty and Manufacturing Company obtained U.S. Patent No. 617,592 (filed 12 March 1898) from David Misell, its English inventor.This "electric device" designed by Misell was powered by "D" batteries laid front to back in a paper tube with the light bulb and a rough brass reflector at the end. The company donated some of these devices to the New York City police, who responded favorably to them.
These early flashlights ran on zinc–carbon batteries, which could not provide a steady electric current and required periodic 'rest' to continue functioning. Because these early flashlights also used energy-inefficient carbon-filament bulbs, "resting" occurred at short intervals. Consequently, they could be used only in brief flashes, hence the popular name flashlight.
Carbon-filament bulbs and fairly crude dry cells made early flashlights an expensive novelty with low sales and low manufacturer interest. Development of the tungsten-filament lamp around 1906, with three times the efficacy of carbon filament types, and improved batteries, made flashlights more useful and popular. By 1922 several types were available; the tubular hand-held variety, a lantern style that could be set down for extended use, pocket size lamps for close work, and large reflector searchlight-type lamps for lighting distant objects. In 1922 there were an estimated 10 million flashlight users in the United States, with annual sales of renewal batteries andflashlights at $20 million, comparable to sales of many line-operated electrical appliances. Miniature lamps developed for flashlight and automotive uses became an important sector of the incandescent lamp manufacturing business.
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