Charles Olson

I had an online inquiry about an author I did not know - Charles Olson.

The question related to Olson's poem "The Kingfishers" and his reference to Stonehenge (?) - is Stonehenge anywhere specifically mentioned - and
the lines

"But the E
cut so rudely on that oldest stone
sounded otherwise,
was differently heard"

I know nothing of this and would be interested in any information anyone can provide about that part of the poem.

Thank you.