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.
Economic history of the United States
After invention of the telephone in 1876 additional development work was required to make it commercially viable. The first telephones were for local calls. Long distance calling came into being in the 1890s, but the technology to make transcontinental calls took until 1915 to be operational.