I've also been searching for a poem I read by Nerdua when I was in high school. The most vivid image was the hooves of horses pounding on the plain like a drumbeat or a heartbeat. I'd really appreciate any tips for what poem this may be, and especially from someone so well read on his work!
There are two you could be referring to; I know one poem that briefly uses horses running through out the beach as a simile, I can’t recall the exact name of the poem but I’ll keep a look out. The poem you’re probably referring to though is “Wind on the Island”. I’m not completely certain but hopefully that helps!
