Which preposition to use with gule

on Occurrences 3%

"Full on this casement shone the wintry moon, And threw warm gules on Madeline's fair breast, As down she knelt for Heaven's grace and boon; Rose-bloom fell on her hands, together prest, And on her silver cross soft amethyst, And on her hair a glory, like a Saint: She seem'd a splendid angel, newly drest, Save wings, for heaven:Porphyro grew faint: She knelt, so pure a thing, so free from mortal taint.

Which preposition to use with  gule