Telecommunication
The conventional telephone was invented independently by Alexander Bell and Elisha Gray in 1876. Antonio Meucci invented the first device that allowed the electrical transmission of voice over a line in 1849. However Meucci's device was of little practical value because it relied upon the electrophonic effect and thus required users to place the receiver in their mouth to "hear" what was being said. The first commercial telephone services were set-up in 1878 and 1879 on both sides of the Atlantic in the cities of New Haven and London.
Invention of the telephone
In the 1880s Meucci was credited with the early invention of inductive loading of telephone wires to increase long-distance signals. Unfortunately, serious burns from an accident, a lack of English, and poor business abilities resulted in Meucci's failing to develop his inventions commercially in America. Meucci demonstrated some sort of instrument in 1849 in Havana, Cuba, however, this may have been a variant of a string telephone that used wire. Meucci has been further credited with the invention of an anti-sidetone circuit. However, examination showed that his solution to sidetone was to maintain two separate telephone circuits and thus use twice as many transmission wires. The anti-sidetone circuit later introduced by Bell Telephone instead canceled sidetone through a feedback process.