The instruction pamphlets (booklets) issued by the air brake companies were written to fill the needs of several different users. As named in the K-triple pamphlet I noted above:
Enginemen, Firemen, Conductors, Brakemen, and Train Crews Generally in Actual Charge of Trains on the Road
Air Brake Foreman, Repairmen and Test Rack Operators
Air Brake Instructors, Inspectrs, Road Foremen of Engines, Train Masters and Officials in Charge of Air Brake Operation and Instruction Generally.
These users were directed to specific sections of the pamphlets.
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