Principles of the layout of signals. Principles of interlocking. Mechanical and electrical interlocking. Single line control. Principles of power point control and detection. Signaling relays. Signal control circuits. Typical selection circuit. Track circuits. Mechanical signalling equipment

CHALLIS W.; SUCH W.; DOSWELL P.; HADAWAY H.; TYLER J.; LOOSEMORE J.; CHAMPION D. / 1952 / A577886