Three short lines, and a whole scene fits inside them. It is November, the day is fading, and a few boys with nothing to do have set fire to a table to keep warm. The speaker simply watches and reports, without saying how they feel about it.
That plainness is what gives the poem its mood. The fading light and the cold suggest a bleak, shrinking world, and the burning table is a small, slightly reckless answer to it. "Idle" makes the boys sound bored, maybe aimless, yet their fire is also practical: they want heat, and they take whatever is at hand. Furniture meant for ordinary use becomes fuel.
The speaker seems quietly absorbed rather than shocked or scolding. The poem holds two feelings together: the sadness of dusk and winter closing in, and a sort of scrappy, human warmth in people making do. It leaves us standing at the edge of the scene, watching the flames against the dark.