Sentence:  Leisurely we moved forward--reached the head of the train--then Andrews, Brown our engineer, and Knight, who also could run an engine, leaped on the locomotive; Alfred Wilson took the top of the cars as <WSD>brakesman</WSD>, and the remainder of us clambered into the foremost baggage car, which, with two others, had been previously uncoupled from the hinder part of the train. 
Meaning of the word marked with <WSD> tags:  A brakeman; a railroad employee responsible for a train's brakes, couplings etc.