On this Day Factola
September 7, 1877
Draft sketches of Phonograph - Documents 1039 and 1040
The following are from The Thomas A. Edison Papers Document No. 1039 and "Technical Note: Phonograph," also from September 7, 1877 which are sketches that appear to be rough designs that Edison drew in more detail in Document 1040. Courtesy of The Thomas A. Edison Papers, Volume 3, Johns Hopkins University Press
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