Apparently an illustration of a Tachyscope in use.
name: label: Collection Creator
content: Hendricks, Gordon
setName: label: See more items in
content: Gordon Hendricks Motion Picture History Papers
label: See more items in
content: Gordon Hendricks Motion Picture History Papers / Series 1: Lantern Slides
container: label: Container
content: Box 1, Folder 33
dataSource: label: Archival Repository
content: Archives Center, National Museum of American History
objectType: label: Type
content: Archival materials