Black and white photograph showing ten unidentified male students standing around a lecture theatre table watching the unidentified male instructor as he points to one of four anaesthesia apparatus, carbon dioxide absorbers.•Black paper label glued on top of photograph with caption written in all caps in white ink: Demonstration of apparatus (Carbon Dioxide absorbers, in section). •Handwritten in black ink on reverse: Frame 14. •Handwritten in grey pencil on reverse: 16. 14 has been crossed out.students, anaesthetic equipment, carbon dioxide absorbers