One of Edison's most famous inventions (as well as his personal favourite) is one of his early ones, the
phonograph. In August
of 1877, Edison was working on a telegraph invention and noticed that when he ran the machine very fast it made a musical sound. Intrigued by this, he set out to find out why it made the music and by the end of the day he had figured it out. Also that day, Edison came up with the idea for the
phonograph, 'a machine that will record the human voice and reproduce it again whenever I want it to, just as this machine records and reproduces telegraph messages!' Edison exclaimed. He was so excited by his new idea that he stopped work on the telegraph machine he had been working on and concentrated all his energy into his new invention. A few days later he gave one of his assistants, John Kruesi, a sketch of the machine he had thought up and told him to make it. When the model was finished it consisted of two small horns, one being the
mouthpiece containing a diaphragm to which was attached a tiny stylus that rested on the tin cylinder. Recording was done by cranking the cylinder and talking into the mouthpiece simultaneously, causing the stylus to vibrate and trace a bumpy path on the tinfoil. To play back the recording, the mouthpiece was swung out of the way and replaced by a much lighter diaphragm and stylus that followed the groves in the tinfoil as the crank was turned and reproduced the voice. All this was built on a budget of $18.
When Edison first tried out his 'talking machine' in his laboratory, all his assistants were amazed and wanted to try it. Edison himself confessed, 'I was never so taken aback in my life. I was always afraid of things that worked the first time'. Edison's phonograph was later advertised in
Scientific American, and
Harper's Weekly gave it a full page spread with illustrations, including a list compiled by Edison of ten major applications his sound recording device could be used for. They are as follows:
Letter writing and dictation
Talking books for the blind
The teaching of elocution
Music recording
Recording of family voices
Music boxes and toys, such as dolls with voices
Talking clocks
Recording the speeches of great men
Educational records
An auxiliary to the telephone
Edison's phonograph was demonstrated at the White House and also at the French Academy of Sciences by DuMoncel, a physicist. While he was demonstrating the phonograph at the Academy, an attending physician, 82-year-old Jean Bouilland, grabbed DuMoncel by the throat and accused him of ventriloquism!
Edison's early invention later led to the more modern record turntable and the technology that later led to the creation of the compact disc. If it had not been for Edison's phonograph, much of the world's music would be lost to us today.