Classroom of men, eight of whom are working at the blackboard on mathematical equations, including two labeled "Velocity of flow of air" and "Flow of gases."  5" x 8".
name: label: Collection Collector
content: Cooney, Debbie
setName: label: See more items in
content: Trade School Photographs
container: label: Container
content: Box 1 (Shared Box)
dataSource: label: Archival Repository
content: Archives Center, National Museum of American History
objectType: label: Type
content: Archival materials
label: Type
content: Photographs