Mile 15.6: BX Tower
The Canada Southern Railway constructed a route from Buffalo to Detroit, through St. Thomas, in 1872. By that time, the L&PS had been operating in the area for over 15 years, so it was up to the CS to protect the diamond where they crossed the L&PS tracks. For this they built a mechanically interlocked system of signals and switches which were controlled from the BX Tower located a few hundred feet east of the L&PS tracks. Levers in the tower allowed the operator to remotely operate switches and signals via a system of control rods that snaked along the ground near the tower. It is interesting that although it is now called BX Tower, there is no reference to this designation in CS or MCR records.
By 1920, when these photos were taken, the CS line had been leased to the Michigan Central who continued to operate BX tower until the NYC merger in the 30's. The tower exists today, cared for by the Elgin County Railroad Museum.
Looking South from Talbot. One of the key features is the mechanical interlocking plant controlled from the nearby BX Tower. The signals were normally lined against the L&PS. Southbound L&PS trains were required to stop clear of Talbot Street and use their whistles to signal the BX tower of their intended destination through the interlocking plant. One whistle for a southbound train on the southbound track and two whistles for a southbound train on the northbound track. Once the tower operator set up the switches, he would provide a clear indication on the semaphore signals to allow the train to proceed. See the tutorial at http://msts.steam4me.net/tutorials/clever_hazard.html where I explain how I made these signals.
(PovRay)
Looking north. Sutherland Press and St. Thomas station in the distance. The diamond is just out of sight to the west.
The L&PS serves the MCR Station on a spur that curves around just behind the BX tower in this view.
(MSTS)
After a recent snowfall. Looking east along the Michigan Central main running past BX Tower. Both L&PS and the MCR operated double track mains through the diamond.
(MSTS)