Who invented the light bulb?
The first electric light was made in 1800 by Humphry Davy, an English scientist. In 1806 Humphrey Davy, demonstrated a powerful electric lamp to the Royal Society. Davy's lamp produced its illumination by creating a blinding electric spark between two charcoal rods.
Much later, in 1860, the English physicist Sir Joseph Wilson Swan (1828-1914) was determined to devise a practical, long-lasting electric light. He found that a carbon paper filament worked well, but burned up quickly. In 1878, he demonstrated his new electric lamps in Newcastle, England.
In 1874, Canadian inventors Henry Woodward and Matthew Evans filed a patent for an electric lamp with different-sized carbon rods held between electrodes in a glass cylinder filled with nitrogen.
The pair tried, unsuccessfully, to commercialize their lamps but eventually sold their patent to Thomas Alva Edison in 1879.
The inventor Edison experimented with thousands of different filaments to find just the right materials to glow well and be long-lasting.
In 1879, Edison discovered that a carbon filament in an oxygen-free bulb glowed but did not burn up for 40 hours. Edison eventually produced a bulb that could glow for over 1500 hours.
He had an idea of how to solve the problems of the electric incandescent light, but had not yet perfected it. His idea was to enclose a platinum burner in a vacuum.
When other inventors had done this the platinum melted, but Edison thought he had solved that problem by building a temperature-sensitive switch into the bulb that would cut off the current when the temperature got too high.
Edison and his team discovered that a carbonized bamboo filament could burn for more than 1,200 hours. Bamboo was used for the filaments in Edison's bulbs until it began to be replaced by longer-lasting materials in the 1880s and early 1900s.