1877: Phonograph invented by Thomas Alva Edison.On this day American inventor Thomas Alva Edison made perhaps his most original discovery, the phonograph. Because the telephone was considered a variation of acoustic telegraphy, Edison during the summer of 1877 was attempting to devise for it, as he had for the automatic telegraph, a machine that would transcribe signals as they were received, in this instance in the form of the human voice, so that they could then be delivered as telegraph messages. Edison employed a stylus-tipped carbon transmitter to make impressions on a strip of paraffined paper. To his astonishment, the scarcely visible indentations generated a vague reproduction of sound when the paper was pulled back beneath the stylus. He unveiled the tinfoil phonograph, which replaced the strip of paper with a cylinder wrapped in tinfoil, in December 1877. More events on this day
|
Artical Related:
This Day In HistoryAugust 14
This Day In HistoryAugust 13
This Day In HistoryAugust 11
This Day In HistoryAugust 10
This Day In HistoryAugust 09




