Innocenzo Manzetti was an Italian inventor who lived from 1826 to 1877. One of his most well-known inventions was a flute playing automaton. The automaton was in the shape of a man. It was filled with pulleys and pumps that moved the flute and blew air across it to the pattern of a preprogramed disc. It operated the same as a player piano.
In 1843, he raised the idea of a speaking telegraph. The idea was to give his automaton the power of speech. He did not get his speaking telegraph working until 1864 or 1865.
Bourseul was an inventor who French inventor who lived from 1829 to 1912. He worked for a telegraph company and began his life of inventing by improving the telegraph system. He was able to invent an electric microphone, but the receiver for his telephone could not make clear sounds. It could not convert the electric signals back into understandable human sounds. In 1854, he wrote a treatise on the use of electric current to transmit voice but was unable to get it working himself.
Meucci was an Italian inventor who lived from 1808 to 1889. He developed some kind of apparatus for communicating voice, but it is not necessarily known what that invention was. He managed to invent some kind of link for communicating his voice from the second floor of his house to his laboratory.
Reis was a German inventor who invented what could be considered the first telephone in 1861. He invented a device into which a person spoke. The sound was converted into electrical signals that were transmitted by wires to a receiver. The receiver translated these pulses back into sounds that were similar to the original source. He called his device a telephone. His telephone was mostly musical though and did not transmit articulate speech very well. However. Thomas Edison considered Reis the inventor of the telephone.
Many people consider Alexander Graham Bell to be the inventor of the telephone. No matter who it was, the invention definitely revolutionized the business world.