Dan, Excellent photo journal of the day!!
It reminds me of when I was still a telecom technician for North Pittsburgh Telephone Company and responded to a trouble call for the the former PRR then Conrail signalling just south of Freeport. This was about 20 years ago. The phone company had analog circuits with an interface device and test point in the signal control box/hut that transmitted the signal commands to wherever... I had to wait on Verizon in King of Prussia to test with me, so I spent some time looking at the rails and seeing where connections were made. I saw jumpers just like what you showed in still photograph number 2. I also was interested in the relays in the signal box/hut since I had worked long ago for power companies on relays. No trains came by that day, however they did the day I worked on a circuit at the wye at the mouth of the Kiski River.
