In 1802, Humphry Davy invented the first electric light. He experimented with electricity and invented an electric battery. When he connected wires to his battery and a piece of carbon, the carbon glowed, producing light. His invention was known as the Electric Arc lamp. And while it produced light, it didn’t produce it for long and was much too bright for practical use.

Over the next seven decades, other inventors also created “light bulbs” but no designs emerged for commerical application. More notably, in 1840, British scientist Warren de la Rue enclosed a coiled platinum filament in a vacuum tube and passed an electric current through it. The design was based on the concept that the high melting point of platinum would allow it to operate at high temperatures and that the evacuated chamber would contain fewer gas molecules to react with the platinum, improving its longevity. Although an efficient design, the cost of the platinum made it impractical for commercial production.

In 1850 an English physicist named Joseph Wilson Swan created a “light bulb” by enclosing carbonized paper filaments in an evacuated glass bulb. And by 1860 he had a working prototype, but the lack of a good vacuum and an adequate supply of electricity resulted in a bulb whose lifetime was much too short to be considered an effective prodcer of light. However, in the 1870’s better vacuum pumps became available and Swan continued experiments on light bulbs. In 1878, Swan developed a longer lasting light bulb using a treated cotton thread that also removed the problem of early bulb blackening.

On July 24, 1874 a Canadian patent was filed by a Toronto medical electrician named Henry Woodward and a colleague Mathew Evans. They built their lamps with different sizes and shapes of carbon rods held between electrodes in glass cylinders filled with nitrogen. Woodward and Evans attempted to commercialize their lamp, but were unsuccessful. They eventually sold their patent to Edison in 1879.
Extract dates and their relevance to development of the light bulb.
system
1802 main, hamphri davy ne pehali electric lite kaa avishkaar kiya.unhone bijli ke saath prayog kiya or ek electric bydaree kaa avishkaar kiya.jab vah taron ko apni bydaree or carbon ke ek tukade se jodta he, to carbon chamakate hue, prakaash kaa utpaadan karata he.unke avishkaar ko electric arq lamp ke rup main janaa jaataa tha.or jab yah prakaash kaa utpaadan karata tha, to yah lambey samay tak iskaa utpaadan nahin karata tha or vyaavhaarik upyog ke liye bahut ujjwal tha.

agle saat dashakon main, anya avishkaarakon ne "lite balb" bhi banaaya, lekin commersical aplication ke liye koi dizine nahin ubhara.adhik vishesh rup se, 1840 main, british vaigyanik warren de laa rue ne ek vaikum tub main ek kundalit platinum philament ko sanlagn kiya or iske madhyam se ek vidyut pravaah paarit kiya.dizin is avadharana par aadhaarit tha ki platinum kaa ucch pighalane bindu ise ucch taapmaana par sanchalit karne kii anumati degaa or khaali kiye gaye kaksh main platinum ke saath pratikriya karne ke liye kam gas anu honge, jo isaki dderghaayu main sudhaar karegaa.haalanki ek kushal dizin, platinum kii laagat ne ise vanijyik utpaadan ke liye avyavhaarik bana diya.

1850 main joseph wilson swaan ke naam se ek angreji bhautik vigyaani ne ek khaali kaanch ke balb main carbonated paper philaments ko gherkar ek "lite balb" banaaya.or 1860 tak unke paas ek kaamkaaji prototip tha, lekin ek achche vaikum kii kami or bijli kii paryaapt aapurti ke parinamswaroop ek balb tha, jiskaa jeevankaal bahut kam tha, jise prakaash kaa ek prabhavi thes mana jaataa tha.haalanki, 1870 main behatar vaikum pump uplabdh ho gaye or swaan ne prakaash balbon par prayog jari rakhaa.1878 main, swaan ne ek upachaarit sooti dhaage kaa upyog karke ek lanbaa sthaayee prakaash balb viksit kiya, jisane shuruaati balb bluekaning kii samasya ko bhi hataa diya.

24 july, 1874 ko ek canadai patent henry woodward or ek sahyogi mathew ivance naamak ek toronto medical electrician dwaara daayar kiya gaya tha.unhone nitrogen se bhare kaanch ke silendar main electrode ke bich yojit carbon chad ke vibhinn aakaaron or aakaar ke saath apane lamp kaa nirmaan kiya.woodward or ivance ne apane deepak kaa vyavsaayeekaran karne kaa prayaas kiya, lekin asafal rahe.unhone antat 1879 main edison ko apana patent bech diya.
prakaash balb ke vikaas ke liye tareekhen or unki praasangikta nikaalen.
user
1802: hamphri davy ne electric arq lamp ke rup main janaa jane vaala pehla electric lite kaa avishkaar kiya, lekin yah bahut ujjwal tha or vyaavhaarik upyog ke liye lambey samay tak nahin chalaa.
1840: warren de laa rue ek platinum philament lite balb banaata he.haalanki yah kushal he, platinum kii laagat ne ise vyavsaayik rup se avyavhaarik bana diya.
1850: joseph wilson swaan ne ek carbonated paper philament lite balb banaaya, lekin ek achche vaikum or paryaapt bijli kii kami ke parinamswaroop bahut kam jeevankaal ke saath ek balb hua.
1870 ke dashak main: behatar vaikum pump uplabdh ho gaye, jisase swaan ko prakaash balbon ke saath prayog jari rakhane kii anumati mili.
1878: swaan ne ek upachaarit sooti dhaage kaa upyog karke ek lambey samay tak chalane vaala prakaash balb viksit kiya or saath hi saath shuruaati balb bluekaning kii samasya ko hal kiya.
24 july, 1874: henry woodward or mathew ivance ne carbon chad or nitrogen se bhare glass silendar ke saath apane deepak ke liye ek canadai patent daayar kiya.ve iskaa vyavsaayeekaran karne main asafal rahe or antat 1879 main edison ko apana patent bech diya.
assistant
<|system|>
</s>
<|user|>
1802 main, hamphri davy ne pehali electric lite kaa avishkaar kiya.unhone bijli ke saath prayog kiya or ek electric bydaree kaa avishkaar kiya.jab vah taron ko apni bydaree or carbon ke ek tukade se jodta he, to carbon chamakate hue, prakaash kaa utpaadan karata he.unke avishkaar ko electric arq lamp ke rup main janaa jaataa tha.or jab yah prakaash kaa utpaadan karata tha, to yah lambey samay tak iskaa utpaadan nahin karata tha or vyaavhaarik upyog ke liye bahut ujjwal tha.

agle saat dashakon main, anya avishkaarakon ne "lite balb" bhi banaaya, lekin commersical aplication ke liye koi dizine nahin ubhara.adhik vishesh rup se, 1840 main, british vaigyanik warren de laa rue ne ek vaikum tub main ek kundalit platinum philament ko sanlagn kiya or iske madhyam se ek vidyut pravaah paarit kiya.dizin is avadharana par aadhaarit tha ki platinum kaa ucch pighalane bindu ise ucch taapmaana par sanchalit karne kii anumati degaa or khaali kiye gaye kaksh main platinum ke saath pratikriya karne ke liye kam gas anu honge, jo isaki dderghaayu main sudhaar karegaa.haalanki ek kushal dizin, platinum kii laagat ne ise vanijyik utpaadan ke liye avyavhaarik bana diya.

1850 main joseph wilson swaan ke naam se ek angreji bhautik vigyaani ne ek khaali kaanch ke balb main carbonated paper philaments ko gherkar ek "lite balb" banaaya.or 1860 tak unke paas ek kaamkaaji prototip tha, lekin ek achche vaikum kii kami or bijli kii paryaapt aapurti ke parinamswaroop ek balb tha, jiskaa jeevankaal bahut kam tha, jise prakaash kaa ek prabhavi thes mana jaataa tha.haalanki, 1870 main behatar vaikum pump uplabdh ho gaye or swaan ne prakaash balbon par prayog jari rakhaa.1878 main, swaan ne ek upachaarit sooti dhaage kaa upyog karke ek lanbaa sthaayee prakaash balb viksit kiya, jisane shuruaati balb bluekaning kii samasya ko bhi hataa diya.

24 july, 1874 ko ek canadai patent henry woodward or ek sahyogi mathew ivance naamak ek toronto medical electrician dwaara daayar kiya gaya tha.unhone nitrogen se bhare kaanch ke silendar main electrode ke bich yojit carbon chad ke vibhinn aakaaron or aakaar ke saath apane lamp kaa nirmaan kiya.woodward or ivance ne apane deepak kaa vyavsaayeekaran karne kaa prayaas kiya, lekin asafal rahe.unhone antat 1879 main edison ko apana patent bech diya.
prakaash balb ke vikaas ke liye tareekhen or unki praasangikta nikaalen.</s>
<|assistant|>
1802: hamphri davy ne electric arq lamp ke rup main janaa jane vaala pehla electric lite kaa avishkaar kiya, lekin yah bahut ujjwal tha or vyaavhaarik upyog ke liye lambey samay tak nahin chalaa.
1840: warren de laa rue ek platinum philament lite balb banaata he.haalanki yah kushal he, platinum kii laagat ne ise vyavsaayik rup se avyavhaarik bana diya.
1850: joseph wilson swaan ne ek carbonated paper philament lite balb banaaya, lekin ek achche vaikum or paryaapt bijli kii kami ke parinamswaroop bahut kam jeevankaal ke saath ek balb hua.
1870 ke dashak main: behatar vaikum pump uplabdh ho gaye, jisase swaan ko prakaash balbon ke saath prayog jari rakhane kii anumati mili.
1878: swaan ne ek upachaarit sooti dhaage kaa upyog karke ek lambey samay tak chalane vaala prakaash balb viksit kiya or saath hi saath shuruaati balb bluekaning kii samasya ko hal kiya.
24 july, 1874: henry woodward or mathew ivance ne carbon chad or nitrogen se bhare glass silendar ke saath apane deepak ke liye ek canadai patent daayar kiya.ve iskaa vyavsaayeekaran karne main asafal rahe or antat 1879 main edison ko apana patent bech diya.</s>
