"And so he was quiet": Tom's submission to what Bloom calls the speaker's "prophetic and menacing sublimity" (Bloom, p. 6) is almost complete. But the "illogic"--Bloom's word again--of the sweeper's counsel of resignation returns with psychic force in Tom's dream. Hearthsides are the proverbial site of intimate conversation, of comfortable disclosure, where the weariness and chill of London's 18th-century street life could go up in smoke.
For Tom, though, a mere child who, by accident of birth or misfortune, finds himself exiled from the fireside, the irrationality of his situation cloaks itself in a dream, reported, not by himself, but by the poem's speaker: "thousands of sweepers ... / Were all of them lock'd up in coffins of black[.]" To the sweepers the hearth is a cinder-floored maw that opens, quite literally for most, into death; the chimneys are coffins of black. And a child, continually blackened with carcinogenic soot, might also be said to occupy a corporeal coffin of black.
The overdetermined dream makes no distinction: in its literalness, and platitudinous religiosity, it restates the irrationality of Tom's innocent perception of his lot in life, while beneath it--beneath it all--the "rationalism" of the era's political economy buoys up a system that finds symptomatic expression in the quasi-religious consolations of the dream.