The crew member whose job it is to keep the fire and steam up in a steam locomotive, and who is responsible for the operating condition of power units on diesel and electric engines
An unlicensed member of the engine, room staff whose duties consist in standing watch in the boiler room and insuring the oil burning equipment is working properly
His job is to ensure that there is sufficient steam for the driver to operate the locomotive, at the same time achieving due economy in the consumption of both coal and water, and anticipating the requirement for steam in the light of the gradients and other features ahead