Edison bulbBy October 1879, Edison's team began to see the first results. On the 22nd, a thin carbon filament burned for 13 hours of the experiment. The longer time was achieved by creating a better vacuum inside the lamp (less oxygen inside the lamp slowed down the burning process). Charcoal organic materials were tested and Japanese bamboo was found to be the best. By the end of 1880, charred bamboo fibers burned for almost 600 hours. Filaments have proven to be the best form to increase the electrical resistance of materials.

Charred bamboo had a high resistance and fit well into the scheme of building an entire electrical system. In 1882, the Edison Electrical Light Company was founded, which had its stations located on Pearl Street, providing New York with light. In 1883 Macy's shop was the first to install new incandescent light bulbs.