"This drumlike device is a carbon-button microphone, patented by Emile Berliner in 1877. It was one of the first ever created and by far the most usable.
Berliner is credited with inventing the carbon-button microphone in 1876. Though there were other microphone technologies in existence, Berliner’s design was more robust than the rest (including a liquid-based mic invented by Alexander Graham Bell). Bell himself was so impressed with the carbon-button that he bought the rights from Berliner for $50,000 (1.1 million dollars in today's money), so he could use it in his telephone prototypes.
Berliner called his microphone a “loose-contact transmitter” because it was composed of two electrical contacts separated by a thin layer of carbon. The “loose” contact was attached to a diaphragm that vibrated when struck by a sound wave. The other was connected to the output.
Unfortunately for Berliner, his patent didn’t survive a legal challenge, which resulted in an 1892 ruling by the U.S. Supreme Court ruling that gave the credit to Thomas Edison. In fact, neither Berliner nor Edison could rightfully claim full credit for the carbon-button mic. The idea for it had been around for years before they began their experiments, though it had never been perfected." Read More
