A system of signalling, for Single lines, which is a system where the control of trains entering a section in advance is controlled by the accepting and carrying of the 'STAFF' or token, for the section.
This staff or token is of wood or metal inscribed with the name of the section to which it belongs
The object of the system is to prevent more than one train being in the section at one time, each signal box is equipped with a device for transmitting and receiving train working signals, as well as indicators to show direction of travel.
In use the following occurs, When a train is ready to be despatched into the section in advance, the signal man would hand the driver the 'STAFF' or hand him,after showing him the staff, a ticket.
The train driver once in possession of the 'staff' or the ticket for the section, now has the authority to proceed through the section, on arrival at the signal box in advance the 'staff' or the ticket is surrendered and placed in the receptacle provided, the driver is issued a staff or a ticket for the next section in advance and so continues.
It will be noted that this system is an absolute system and only allows ONE train at one time to enter the section.
the use of the ticket is to allow for instances where more trains will proceed in one direction than the other (i.e. 5 trains heading West, with one train to head East, the first four would carry tickets and the fifth would carry the staff.
