I think that Doaker's work on the railroads represents a couple of elements. The first is that it shows consistency and a sense of constancy in a world of mutability and change. Doaker does not live by anything other than the steadiness of work, something in which he is almost the heartbeat of the family. In contrast to his brother, Wining Boy who sought to make it rich in the music industry only to not materialize and wander, Doaker "stays on track" in providing for his family and operating in a manner by which he is the structure for the others in his family. The fact that Doaker works on the railroads is significant for being able to articulate the path that must be followed. Doaker is the character who gives the most amount of insight on the piano, its connection to the family, and its overall relevance. While Berniece is incredibly conflicted with the piano and does not really formulate a heart felt belief until the end, and Boy Willie is about generating profit from it, Doaker understands its significance and he provides the lane that needs to be followed in acknowledging its importance. In this, Doaker follows the path that he lays down and is the force by which others can do the same. In this, his work on the railroad helps to heighten this.