Hump master in a Chicago and Northwestern i.e. North Western railroad yard operating a signal switch system which extends the length of the hump track. He is thus able to control movements of locomotives pushing the train over the hump from his post at the hump office; Chicago, Ill

Proviso Yards.
Title from FSA or OWI agency caption.
12002-1.
Transfer from U.S. Office of War Information, 1944.
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