Bell Labs' Holmdel Computing Center training videos

What was intended as a training video for new employees to Bell Labs' iconic Holmdel Computing Center (which after all was where the likes of C and Unix originated) in 1973 is now a fascinating insight to high-end computing back in the pre-PC age and a nostalgia fest of old iron. This reminds me of my minicomputer days at university, writing programmes in a Volker-Craig terminal and then going to the library to collect my print outs on big fan fold paper...