I run hot and cold on Ted Hughes; he was Sylvia Plath's husband, and I generally find him a bit opaque and modern. But he wrote quite a bit about horses. This one is probably my favorite.
I climbed through woods in the hour-before-dawn dark.
Evil air, a frost-making stillness,
Not a leaf, not a bird -
A world cast in frost. I came out above the wood
Where my breath left tortuous statues in the iron light.
But the valleys were draining the darkness
Till the moorline - blackening dregs of the brightening grey -
Halved the sky ahead. And I saw the horses:
Huge in the dense grey - ten together -
Megalith-still. They breathed, making no move,
with draped manes and tilted hind-hooves,
Making no sound.
I passed: not one snorted or jerked its head.
Grey silent fragments
Of a grey silent world.
I listened in emptiness on the moor-ridge.
The curlew's tear turned its edge on the silence.
Slowly detail leafed from the darkness. Then the sun
Orange, red, red erupted
Silently, and splitting to its core tore and flung cloud,
Shook the gulf open, showed blue,
And the big planets hanging -
Stumbling in the fever of a dream, down towards
The dark woods, from the kindling tops,
And came to the horses.
There, still they stood,
But now steaming and glistening under the flow of light,
Their draped stone manes, their tilted hind-hooves
Stirring under a thaw while all around them
The frost showed its fires. But still they made no sound.
Not one snorted or stamped,
Their hung heads patient as the horizons,
High over valleys in the red levelling rays -
In din of crowded streets, going among the years, the faces,
May I still meet my memory in so lonely a place
Between the streams and the red clouds, hearing the curlews,
Hearing the horizons endure.