Url https://edisondigital.rutgers.edu/document/N019097 Resource class dctype:Text Title [N019097], Technical Note, William Joseph Hammer, June 21st, 1880 Creator Hammer, William Joseph Publisher Thomas A. Edison Papers, School of Arts and Sciences, Rutgers University Date 1880-06-21 Type Technical Note Identifier N019097 Source 30:937 Rights Thomas Edison National Historical Park Date Created 1880-06-21 Has Version https://archive.org/details/edisonmicrofilm30/page/n946/mode/1up Archive.org Viewer, Microfilm Series Reel 30 Is Part Of N019-F Uri https://edisondigital.rutgers.edu/document/N019097 https://edisondigital.rutgers.edu/document/N019097 --