The lowest note does not carry far, leading Montagu to hypothesize that only the middle note was used in a rhythmic signalling code.
2.
Historically, push pull trains with steam power provided the driver with basic controls at the cab end along with a bell or other signalling code system to communicate with the fireman located in the engine itself in order to pass commands to adjust controls not available in the cab.
3.
W / C Russell explained the operation of the school in an interview with the Toronto Daily Star . " During this period the men will receive lectures in mathematics, radio theory, hygiene, first aid, law and administration, armament, anti-gas work, signalling code and procedure, visual signalling with lamps and flags.
मोबाइल