Or each other. We watch the fire blazing, And feel the roots of the house move, but sit on, Seeing the window tremble to come in, Hearing the stones cry out under the horizons.
After more enjambment, the poem ends the way it began: demonstrating the sheer force of the wind with striking imagery and metaphors.
The people in the house uneasily watch the fire as they feel the house shake in the wind. It might not literally have roots, but it does have foundations, and the wind is shaking them. In addition, it's making the glass in the window tremble, like it'll break.
Can the family actually "hear stones cry under the horizons"? Probably not. But the personified stones are crying out to show that the wind is powerful. It's bringing them to life and inflicting pain on them, even though they're inanimate objects. The wind is like a mystical force that can make non-living things come alive, if only to make them suffer. (It sounds like something a pro-wrestler would do—like the wind is Dwayne "The Rock" Johnson or something.)
And with that image, just like a wind suddenly dying down, our poem is done.