On this day in 1877, the American businessman Thomas Edison announced the invention of the phonograph, a revolutionary device that could record and play back sounds.
Edison first thought about the phonograph while he was trying to invent the telephone and the telegraph.
He began experimenting with a stylus, tinfoil cylinder and 2 needles – one needle for recording the sound, and the other for playing it back. The first needle would indent the sound vibrations into the cylinder covered with tin foil, while the other one would copy the exact indentations to produce the same sound again.
