Invention of the telephone useful and widespread apparatus it is now. The telephone exchange was an idea of the Hungarian engineer Tivadar Puskás (1844–1893) in 1876, while he was working for Thomas Edison on a telegraph exchange. Puskás was working on his idea for an electrical telegraph exchange when Alexander Graham Bell received the first patent for the telephone. This caused Puskás to take a fresh look at his own work and he refocused on perfecting a design for a telephone exchange. He then got in touch with the U.S. inventor Thomas Edison who liked the design. According to Edison, "Tivadar Puskas was the
Invention of the telephone Company, and the results were covered up by STC's chairman Sir Frank Gill to maintain Bell's reputation. An early voice communicating device was invented around 1854 by Antonio Meucci, who called it a "telettrofono". In 1871 Meucci filed a caveat at the US Patent Office. His caveat describes his invention, but does not mention a diaphragm, electromagnet, conversion of sound into electrical waves, conversion of electrical waves into sound, or other essential features of an electromagnetic telephone. The first American demonstration of Meucci's invention took place in Staten Island, New York in 1854. In 1861, a description of it was