Invention of the telephone
The carbon microphone was independently developed around 1878 by David Edward Hughes in England and Emile Berliner and Thomas Edison in the US. Although Edison was awarded the first patent in mid-1877, Hughes had demonstrated his working device in front of many witnesses some years earlier, and most historians credit him with its invention.
Voicemail
The first public records describing voice recording were reported in a New York newspaper and the Scientific American in November 1877. Thomas A. Edison had announced the invention of his "phonograph" saying "the object was to record telephone messages and transmit them again by telephone." Edison applied for a U.S. patent in December 1877 and shortly thereafter demonstrated the machine to publishers, the U.S. congress and President Hayes, recording and playing "Mary had a little lamb... " and "there was a little girl who had a little curl... " and other ditties popular at the time. In an article outlining his own ideas of the future usefulness of his machine Edison's list began with "Letter writing, and all kinds of dictation without the aid of a stenographer." In other words, "voice messages" or "Voice-mail". By 1914, Edison's phonograph business included a dictating machine (the Ediphone) and the "Telescribe", a machine combining the phonograph and the telephone, which recorded both sides of telephone conversations.