detectors

point lock

iock bar

stretcher bar

in the middle of the track a little in front of the toes of the tongue rail

near and parallel to inner side of one of the rails

at right angle to the rail

near and parallel to inner side of both the rails

to ensure that each switch is correctly set

to ensure that the point may not be operated while the train is on it

to detect any obstruction between and tongue rail

none of the above

triangle

turntable

traverser

scotch block

changing the direction of engine

transferring wagons to and from parallel tracks without shunting

separating all the sidings and shunting lines from main lines

preventing the vehicles from running off the track