Caption: A large transformer on a wide gauge dolly is rotated on a turntable to allow the dolly to be moved to the mounting location of the transformers. The transformer will be rolled off the dolly into position via the rails on top of the dolly and rails at the mounting location. Note that there are four rails on the left side of the turntable and two on the right. The main generator building would be just to the left of the photo. It would appear that the wide gauge rails ran into that building as well. The rails to the right arced around the transformer and breaker areas and connected to the CNR line between Ottawa and Arnprior. My Grandfather worked on several large infrastructure projects in the 1930's and took photos of several locations. Not much in the way of safety gear or appliances in those days other than a hat to keep the sun off your head.