Url https://edisondigital.rutgers.edu/document/NV15136 Resource class dctype:Text Title [NV15136], Technical Note, Thomas Alva Edison, July 28th, 1876 Creator Edison, Thomas Alva Subject Multiple telegraphy (duplex, quadruplex) Acoustic telegraphy Publisher Thomas A. Edison Papers, School of Arts and Sciences, Rutgers University Date 1876-07-28 Type Technical Note Identifier NV15136 Source 4:443 Rights Thomas Edison National Historical Park Date Created 1876-07-28 Has Version https://archive.org/details/edisonmicrofilm4/page/n451/mode/1up Archive.org Viewer, Microfilm Series Reel 4 Is Part Of NV15-F Uri https://edisondigital.rutgers.edu/document/NV15136 https://edisondigital.rutgers.edu/document/NV15136 --