Card with blue ribbons labeled "Trans-Continental Telephone--Diamond Disc: Edison Day celebration Panama Pacific Exposition, Edison Laboratory, October 21, 1915" (three plastic cards)
name: label: Collection Creator
content: Hammer, William J. (William Joseph), 1858-1934 (electrical engineer)
setName: label: See more items in
content: William J. Hammer Collection
label: See more items in
content: William J. Hammer Collection / Series 2: Edisonia / 2.7: Speeches, Testimonials, Invitations / Social Occasions
container: label: Container
content: Box 29, Folder 3
dataSource: label: Archival Repository
content: Archives Center, National Museum of American History
objectType: label: Type
content: Archival materials