The ordinary truck is fitted with stakes and bands to protect the load. It is about 4 ft. wide and 12 ft. long, and will carry from 1 to 6 tons, according to the commodity. A train dispatcher in the central station controls all train movements. He has over 300 telephone connections with the tunnels, and keeps a regular sheet of train locations and movements. The tunnels are lighted at all connecting points and elsewhere when other than train lights are needed.
Signals protect the trainmen when delivering or switching trucks.
There has never been a major accident in the tunnels. Signs are placed showing the names of the streets above any part of the tunnels. Nothing in the way of safety appliances is wanting. Some idea of the volume of traffic created by trade and manufacture in Chicago may be gained from the fact , that over 70,000 horse vans, motor lorries, and delivery cars are engaged in carrying it, and a considerable part of the conveyance performed by these vehicles is to and from railway terminals. Freight is of many kinds, but is divided into two main classes, freight in bulk and package freight, or small lots.