Alexander Graham Bell patented the telephone in 1876.
Bell placed the first telephone call between New York City and Chicago in 1892. His early phone design consisted of a transmitter to turn vibrations from his voice into an electric current and a receiver.
#10 An old choir director of mine lived next door to one of the guys who developed the earliest patents for home microwave ovens. They were approved and being marketed by the 70s, but he wouldn't have one in his house until the 90s because they still leaked too much radiation of some sort.