Lawrence Sperry staved a hole in it. In 1979, Sperry was inducted into the International Air & Space Hall of Fame at the San Diego Air & Space Museum. Sperry was inducted into the Naval Aviation Hall of Honor at the National Naval Aviation Museum in Pensacola, Florida, in 1992. Lawrence Sperry Lawrence Burst Sperry (21 December 1892, Chicago, Illinois, United States – December 13, 1923, English Channel) was an aviation pioneer. He was the third son of the gyrocompass co-inventor, Elmer Ambrose Sperry and his wife Zula. Sperry invented the first autopilot, which he demonstrated with startling success in France in
Invention of the telephone 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. Thomas Alva Edison took the next step in improving the telephone with his invention in 1878 of the carbon grain "transmitter" (microphone) that provided a strong voice signal on the transmitting circuit that made long-distance calls practical. Edison discovered that carbon grains, squeezed between two metal plates, had a variable electrical resistance that was related