The central shaft was dug to provide two additional headings to help speed up tunnel construction and later ventilation. When it was completed it was 1028 feet deep. This included a ten foot sump hole that was used to collect the incredible amounts of water that flowed in at a constant rate. It had sixty-four floors with an opening in the middle to accommodate the elevator used for the moving of men and rock.
On October 17, 1867 there was an explosion and fire that destroyed the central shaft workings. Thirteen men at the bottom of the then 583-foot pit were killed in the accident. It took a year of work to recover all of the bodies.
Central and West Shaft buildings.
This is a view of the building on top of the vent shaft today.
View of the exhaust ports at central shaft.
This is a 150-foot scale model of the bottom of the tunnel at central shaft. The shaft now ends 25 feet above the top of the tunnel. This was done to provide protection from falling rock from hitting a train below. The side vent tubes are offset in the tunnel by about 35 feet off of the centerline of the shaft. One tube bends down towards the tunnel to the east and the other to the opposite side of the tunnel to the west.
To build a HO scale model of the tunnel you would have to devote 288.28 feet of space in a straight line. Central Shaft would have to be 11.81 feet high!