Diagram showing Manager's Photometer, designed and built by Hammer
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 / 2.9: Edison Storage Battery Data; Edison Electric Illuminating Company / Boston Electric Illuminating Company:
unitdate: label: Date
content: June 16, 1887
container: label: Container
content: Box 31, Folder 4
dataSource: label: Archival Repository
content: Archives Center, National Museum of American History
objectType: label: Type
content: Archival materials