1 and 1809, an Englishman Humphrey David invented the arc lamp.
2. 1854, Henry Gaubert, a German watchmaker who immigrated to the United States, invented the carbonized bamboo filament lamp, and kept it on for 400 hours in a vacuum glass bottle, but did not apply for a patent.
3. 1878, joseph swan, an Englishman, also completed a similar carbon filament lamp and applied for a patent.
4. 1874, two Canadian electricians applied for a patent for electric lamp: nitrogen was filled under the glass bulb to make the electrified carbon rod glow.
5. In1875, Edison bought this patent, and in 1880, he made a carbonized bamboo filament lamp that could be used continuously for 1200 hours.