Bartram acts as a foil for Brand in the story, meaning that his character—when juxtaposed with Brand’s—reveals important information about Brand, and about the intentions of the story as a whole. The following passage highlights the difference between how the two men approach the job of tending to the lime kiln:
It is a lonesome, and, when the character is inclined to thought, may be an intensely thoughtful occupation; as it proved in the case of Ethan Brand, who had mused to such strange purpose, in days gone by, while the fire in this very kiln was burning.
The man, who now watched the fire, was of a different order, and troubled himself with no thoughts save the very few that were requisite to his business.
As this passage makes clear, Bartram is, in many ways, the opposite of Brand—he is a down-to-earth and practical man, more interested in doing his job well and spending time with his son than thinking about anything in particular. As the narrator puts it, he “troubled himself with no thoughts” except ones that helped him better perform his job.
Brand, on the other hand, approached lime-burning in an “intensely thoughtful way,” and ultimately lost himself in existential ruminations about the nature of knowledge and sin. In this way, Bartram represents the kind of simple and happy man that Brand could have been had the isolation of the job not warped his sense of reality. More than that, Bartram seems to represent to Hawthorne the ideal man—someone who prioritizes work and family over pride and greed.