Read these lines from "It Sifts from Leaden Sieves.” It sifts from Leaden Sieves —
It powders all the Wood.
It fills with Alabaster Wool
The Wrinkles of the Road —

How do these lines develop the theme that nature has power over human efforts?

They suggest either snow or rain, but the deeper meaning of decay over time is clear, too.

They depict a lot of rain from a leaden (gray) sky that smooths the wrinkles in an old dirt road.

They compare snow to a natural substance (wool) and illustrate it covering the road, a symbol of human progress.

They suggest the madness that eventually overtook the author of the poem.