A picture is worth a thousand words… or so the saying goes. That’s especially true when trying to train someone. Concepts and procedures are much easier to grasp if the pupil can see the object. Since the 1960s, the electronic display of training materials became increasing common: first, via low-cost videotape, to today, where the simplest laptop or tablet can show videos from YouTube and the like.
But what happened before there was video available? Companies with large training budgets could utilize 16mm movies, but for less ambitious needs, there was the “lantern slide” projected onto a training room screen.
General Electric, manufacturer of the motor and controller for BC Electric’s Brill trolleycoaches issued training materials reproduced on transparent film. Unlike the 35mm transparencies we may still see today, these slides were mounted inside two small pieces of glass, about 8cm square. They were extremely fragile, and so were provided in protective boxes to prevent damage. The boxes also contained partitions to avoid the problem of slides getting out of sequence.
While going through some of our donated materials, we came across a box of thirty-five slides to be used in training personnel in electrical repairs. The physical slides have been archived, but we felt that members may be interested in the content depicted. Their large size (compared to 35mm slides) prevented using our slide scanner to digitize them. But an online search offered a ‘quick-and-dirty’ solution: a white screen was displayed on a cellphone to provide illumination. (A scanner does not provide the illumination necessary for the scanner to recognize the image. The white screen however lights the slide from behind.) The slide was placed on top of the phone screen, and a photo taken with a second cellphone.
The resultant images are not as sharp as direct scanning and appear to have slightly higher contrast than the original image. In addition, because it is almost impossible to keep the cell phone taking the photo perfectly parallel, there are some parallax issues evident. But despite these imperfections, we get to see what those electricians many years ago would have seen as they received instruction on how to maintain the new vehicles.
This is an Agfa slide projector, broadly like the type used to show the slides (Wikipedia)
