Edison closed the 1870s with a further world-changing achievement. The mission to replace gas lighting systems with a safer, easier electric version suited Edison's unique ability to combine existing fragmentary knowledge into a practical, operating whole. The construction of the electric power and lighting system, begun in 1878, was a huge undertaking in every way: concept, imagination, manpower, financial funding, research, manufacture, and marketing. These, together with painstaking research, required the production of every element in the process from the electricity generators through the entire distribution system to the final light bulb and switch. The resulting system went live at the Pearl Street plant in New York City on September 4, 1882.
In 1880, while experimenting with light bulb filaments, Edison's team discovered and patented the "etheric (or Edison) effect" in which electricity was detected passing through the vacuum from the heated filament to a metal plate. While not recognizing the importance of this phenomenon at the time, Edison was later able to direct the patented rights to Guglielmo Marconi for use in his wireless telegraphy discoveries.