The Use and Operation of the Overhead Projector / L'Opération du rétroprojecteur

I0006-09-0087: The Concordia University Audio-Visual Department demonstrates the use and operation of an overhead projector from 1976. The second half of this video is presented in French.
More info: concordia.accesstomemory.org/...

[@valerieodom8442]

I cant get in my overhead projector to change bulb