A small group of old soldiers sits on the street, passing around bottles of raw wine and singing while the wind blows and the cold sets in. That's the whole scene, and the poem leaves it almost bare, with no explanation of who these men are or why they are there.
The speaker mostly watches. There is no complaint or lecture, just a quiet, steady attention. Still, the details do some work. "Raw" wine is rough and unrefined, and the street and weather suggest hardship. Yet the men sing, and the title, "Singing bottles," oddly gives the voice to the bottles themselves, as if the wine and the men have blended into one sound.
The mood is a mix of sadness and stubborn warmth. We can sense age, loss, and perhaps memories the men carry, but we also see companionship and defiance. The last line, "through wind and cold," lingers on their endurance. The cold is real, but the singing keeps going.